Discussion

Food and AgricultureBefore completing your post, review the

Week 2: Food & Agriculture (Links to an external site.)Links to an external site.

interactive video, which is designed to assist you in understanding more about this week’s topic and to help you organize your initial post.
In the United States, we are fortunate to have an abundant supply of food. However, this abundance is largely due to advances in agricultural technologies, which have in turn created numerous concerns surrounding our food sources. Provide at least two recent (since the Green Revolution ended) examples of how the United States has increased its food production, and discuss how these changes have affected both the environment and food safety. Possible innovations you might cover include, but are not limited to: GM agriculture, polyculture farming, permaculture farming, vertical farms, small-scale organic farming, aquaponics, concentrated animal feeding operations, urban gardening (rooftop and vacant lot), not-till farming, precision farming, use of drones, and use of GPS technology. Your initial post should be at least 250 words in length. Utilize at least two scholarly or reputable resources and your textbook to support your claims. Cite your sources in APA format. Quoted text should constitute no more than ten percent of your post. Respond to at least two of your classmates’ posts by Day 7.

. Steve Mcsweeny/iStock/Thinkstock

Learning Objective

After studying this chapter, you should be able to:

• Discuss how a growing population combined with changing diets is putting increased pressure on world
food supplies.

• Describe how modern or conventional agricultural approaches lead to environmental impacts on soil
fertility, water quality, air quality, and wildlife habitat.

• Explain the basic principle behind genetic engineering of crops and discuss the environmental and
health debates surrounding the development and expanded use of biotechnology.

• Discuss the state of the world’s fisheries and describe how an indicator known as the seafood print can
be used to measure the impact of different nations on global fish stocks.

• Discuss the difference in environmental and social impact between foods grown locally and those
shipped over long distances.

Feeding the World

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IntroDuctIon

Pre-Test

1. the poorest people on the planet spend from _______ to ________ percent of their income
on food.

a. 10 to 2

b. 20 to

c. 30 to

d. 50 to

2. Which of the following is not an attribute that has an important impact on soil quality?

a. texture
b. Depth
c. color
d. Permeability

3. A situation in which weeds evolve so that chemical sprays are no longer effective in

controlling them is known as

a. pesticide resistance.
b. herbicide resistance.
c. nutrient management.
d. chemical resistance.

4. A measure developed by marine biologists to estimate the amount of primary

production required to make a pound of different kinds of fish is known as

a. the ecological footprint.
b. the seafood print.
c. the marine food web.
d. sustainable production.

5. Which of the following is a method that promotes nutrient recycling?
a. Having mega-sized livestock
b. Having a chicken farm
c. Having a mixed crop-livestock operation
d. Having a corn and grain farm

Introduction
Severe droughts in china and russia, floods in Australia, and a deep freeze in Mexico reduced
global crop yields in 2010 and caused food prices to increase across the world. Between July
2010 and January 2011, the global price of wheat increased by 66.8 percent, from $190 per
metric ton to $327 per metric ton (Index Mundi, 2011). the price of many other food com-
modities went up by similar amounts so that in January 2011, the Global Food Price Index
reached its highest level ever. While most of the wealthier people in the world could afford an
extra 25 or 50 cents for a loaf of bread, in developing countries, rising food prices pushed 44
million more people into extreme poverty during this time period.

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SEctIon 3.1 The Global Food Crisis—FeedinG nine billion

now that the human population has surpassed seven billion and continues to grow at the rate
of roughly 80 million every year, agricultural experts are asking whether the world can con-
tinue to produce enough food for everyone. Along with total growth, people in many devel-
oping countries such as china and India are becoming wealthier and are eating a richer diet,
including more meat, which requires more cropland to produce.

the problem is that conventional approaches to agriculture lead to a number of serious envi-
ronmental impacts. Attempts to feed a growing human population will, if we continue to use
the same techniques, only worsen those impacts. consider the following:

• Agriculture in the united States accounts for over 80 percent of all freshwater use
and as much as 90 percent in some western states (http://www.ers.usda.gov
/topics/farm-practices-management/irrigation-water-use.aspx#.uitvhJu_Yrk).

• runoff of pesticides and other chemicals from agricultural fields is a major source of
water pollution (http://www.fws.gov/contaminants/Issues/Pesticides.cfm).

• Agriculture accounts for roughly 17 percent of all energy use in the united States
and is therefore a major contributor to global climate change (http://epa.gov
/climatechange/ghgemissions/sources/agriculture.html).

• Large-scale meat production in what are known as concentrated animal feeding
operations (cAFos) requires large doses of antibiotics to control disease and has
been linked to the development of antibiotic-resistant bacteria (http://www.ncifap
.org/_images/212-2_Antbiorprt_FIn_web%206.7.10%202 ).

these are just a handful of some of the environmental impacts from agriculture that will be
covered in this chapter. they suggest that a business-as-usual approach to feeding the world
is not sustainable. Alternative approaches that increase yields while balancing environmen-
tal, human health, and wildlife concerns will be needed. As these readings will demonstrate,
the answers to how we can do this vary from group to group, and they are the source of much
political and scientific debate. We start with a review of the sheer challenge involved in feed-
ing a world of nine billion or more. the second section documents the environmental impacts
of conventional approaches to agriculture. Section 3.3 introduces what is perhaps one of the
most controversial subjects in environmental science today—the issue of biotechnology and
genetically modified (GM) crops. We’ll see that the GM debate is highly polarized with each
side accusing the other of practicing “junk science” and spreading lies to advance their argu-
ments. Section 3.4 takes a look at the state of the world’s fisheries and how population growth
and destructive fishing practices are threatening this resource. the chapter concludes on a
more hopeful note with a discussion of efforts to produce more food locally and sustainably.

3.1 The Global Food Crisis—Feeding Nine Billion
By the 1960s, rising populations and stagnant world grain production combined to create the
specter of massive famine. In response, scientists and development organizations launched what
came to be known as the green revolution. This revolution involved the development of new
varieties of wheat, rice, and other grains that doubled yields and allowed farmers in tropical
regions to grow two crops a year instead of just one. The results were staggering: famine was
largely avoided in certain regions of the world and green revolution grain varieties came to
dominate farming in many regions of the world.

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http://www.ers.usda.gov/topics/farm-practices-management/irrigation-water-use.aspx#.UiTvhJU_YRk

http://www.fws.gov/contaminants/Issues/Pesticides.cfm

http://epa.gov/climatechange/ghgemissions/sources/agriculture.html

http://www.ncifap.org/_images/212-2_AntbioRprt_FIN_web%206.7.10%202

SEctIon 3.1 The Global Food Crisis—FeedinG nine billion

However, in order to grow green revolution varieties, farmers were required to use much larger
quantities of irrigated water, fertilizers for plant growth, and pesticides and herbicides to con-
trol insect pests and weeds. These varieties also did better when they were planted in large
blocks of a single variety, known as monocultures. This, in turn, necessitated the use of even
more irrigated water, fertilizers, pesticides, and herbicides. Today, crop yields from green revo-
lution varieties have peaked and are no longer responding the way they once did to increased
applications of fertilizer and other inputs. Furthermore, over-pumping of groundwater for irri-
gation and over-use of synthetic fertilizers, pesticides, and herbicides are taking an increasing
environmental toll.

In the following article, Joel K. Bourne, Jr., of national Geographic Magazine reviews the history
of the first green revolution and explains why it might be time for another one. With crop yields
stagnant and the population still growing (though at a slower rate than 50 years ago)—and
increasing affluence in countries like China and India spurring increased food consumption—
Bourne argues that we could be on the verge of a global food crisis, especially for the world’s
poorest. The question is whether the next revolution in agriculture will focus on high-tech
approaches such as genetic engineering or on new ways of farming in a less environmentally
destructive manner sometimes referred to as agroecology or sustainable agriculture, or both.
This question will be the subject of further discussion in the sections to come.

By Joel K. Bourne, Jr.
It is the simplest, most natural of acts, akin to breathing and walking upright. We sit down at
the dinner table, pick up a fork, and take a juicy bite, oblivious to the double helping of global
ramifications on our plate. our beef comes from Iowa, fed by nebraska corn. our grapes come
from chile, our bananas from Honduras, our olive oil from Sicily, our apple juice—not from
Washington State but all the way from china. Modern society has relieved us of the burden
of growing, harvesting, even preparing our daily bread, in exchange for the burden of simply
paying for it. only when prices rise do we take notice. And the consequences of our inatten-
tion are profound.

Last year [2007] the skyrocketing cost of food was a wake-up call for the planet. Between
2005 and the summer of 2008, the price of wheat and corn tripled, and the price of rice
climbed fivefold, spurring food riots in nearly two dozen countries and pushing 75 million
more people into poverty. But unlike previous shocks driven by short-term food shortages,
this price spike came in a year when the world’s farmers reaped a record grain crop. this
time, the high prices were a symptom of a larger problem tugging at the strands of our world-
wide food web, one that’s not going away anytime soon. Simply put: For most of the past
decade, the world has been consuming more food than it has been producing. After years of
drawing down stockpiles, in 2007 the world saw global carryover stocks fall to 61 days of
global consumption, the second lowest on record.

“Agricultural productivity growth is only one to two percent a year,” warned Joachim von
Braun, director general of the International Food Policy research Institute in Washington,
D.c., at the height of the crisis. “this is too low to meet population growth and increased
demand.”

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SEctIon 3.1 The Global Food Crisis—FeedinG nine billion

High prices are the ultimate signal that demand is outstripping supply, that there is simply
not enough food to go around. Such agflation hits the poorest billion people on the planet
the hardest, since they typically spend 50 to 70 percent of their income on food. Even though
prices have fallen with the imploding world economy, they are still near record highs, and the
underlying problems of low stockpiles, rising population, and flattening yield growth remain.
climate change—with its hotter growing seasons and increasing water scarcity—is projected
to reduce future harvests in much of the world, raising the specter of what some scientists are
now calling a perpetual food crisis.

So What Is a Hot, Crowded, and Hungry World to Do?
that’s the question von Braun and his colleagues at the consultative Group on International
Agricultural research are wrestling with right now. this is the group of world-renowned agri-
cultural research centers that helped more than double the world’s average yields of corn,
rice, and wheat between the mid-1950s and the mid-1990s, an achievement so staggering
it was dubbed the green revolution. Yet with world population spiraling toward nine billion
by mid-century, these experts now say we need a repeat performance, doubling current food
production by 2030.

In other words, we need another green revolution. And we need it in half the time. [. . .]

The High Cost of Meat
It’s no coincidence that as countries like china and India prosper and their people move up
the food ladder, demand for grain has increased. For as tasty as that sweet-and-sour pork
may be, eating meat is an incredibly inefficient way to feed oneself. It takes up to five times
more grain to get the equivalent amount of calories from eating pork as from simply eating
grain itself—ten times if we’re talking about grain-fattened u.S. beef. As more grain has been
diverted to livestock and to the production of biofuels for cars, annual worldwide consump-
tion of grain has risen from 815 million metric tons in 1960 to 2.16 billion in 2008. Since

2005, the mad rush to biofuels alone has
pushed grain-consumption growth from
about 20 million tons annually to 50 mil-
lion tons, according to Lester Brown of
the Earth Policy Institute.

Even china, the second largest corn-
growing nation on the planet, can’t grow
enough grain to feed all its pigs. Most of
the shortfall is made up with imported
soybeans from the u.S. or Brazil, one of
the few countries with the potential to
expand its cropland—often by plowing

up rain forest. Increasing demand for food, feed, and biofuels has been a major driver of defor-
estation in the tropics. Between 1980 and 2000 more than half of new cropland acreage in
the tropics was carved out of intact rain forests; Brazil alone increased its soybean acreage in
Amazonia 10 percent a year from 1990 to 2005.

Consider This
using your understanding of trophic lev-
els from chapter 1, why does it take five to
ten times more grain to get the equivalent
amount of calories from pork or beef com-
pared to simply eating the grain itself ?

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SEctIon 3.1 The Global Food Crisis—FeedinG nine billion

Some of those Brazilian soybeans may
end up in the troughs of Guangzhou
Lizhi Farms, the largest cAFo [con-
centrated animal feeding operation]
in Guangdong Province. tucked into a
green valley just off a four-lane high-
way that’s still being built, some 60
white hog houses are scattered around
large ponds, part of the waste-treat-
ment system for 100,000 hogs. the
city of Guangzhou is also building a
brand-new meatpacking plant that will
slaughter 5,000 head a day. By the time
china has 1.5 billion people, sometime
in the next 20 years, some experts
predict they’ll need another 200 mil-
lion hogs just to keep up. And that’s
just china. World meat consumption
is expected to double by 2050. that
means we’re going to need a whole lot
more grain.

The First Green Revolution
this isn’t the first time the world has stood at the brink of a food crisis—it’s only the most
recent iteration. At 83, Gurcharan Singh Kalkat has lived long enough to remember one of
the worst famines of the 20th century. In 1943 as many as four million people died in the
“Malthusian correction” known as the Bengal Famine. For the following two decades, India
had to import millions of tons of grain to feed its people.

then came the green revolution. In the mid-1960s, as India was struggling to feed its people
during yet another crippling drought, an American plant breeder named norman Borlaug
was working with Indian researchers to bring his high-yielding wheat varieties to Punjab. the
new seeds were a godsend, says Kalkat, who was deputy director of agriculture for Punjab at
the time. By 1970, farmers had nearly tripled their production with the same amount of work.
“We had a big problem with what to do with the surplus,” says Kalkat. “We closed schools one
month early to store the wheat crop in the buildings.”

Borlaug was born in Iowa and saw his mission as spreading the high-yield farming methods
that had turned the American Midwest into the world’s breadbasket to impoverished places
throughout the world. His new dwarf wheat varieties, with their short, stocky stems support-
ing full, fat seed heads, were a startling breakthrough. they could produce grain like no other
wheat ever seen—as long as there was plenty of water and synthetic fertilizer and little com-
petition from weeds or insects. to that end, the Indian government subsidized canals, fertilizer,
and the drilling of tube wells for irrigation and gave farmers free electricity to pump the water.
the new wheat varieties quickly spread throughout Asia, changing the traditional farming
practices of millions of farmers, and were soon followed by new strains of “miracle” rice. the
new crops matured faster and enabled farmers to grow two crops a year instead of one. today
a double crop of wheat, rice, or cotton is the norm in Punjab, which, with neighboring Haryana,
recently supplied more than 90 percent of the wheat needed by grain-deficient states in India.

Imaginechina via AP Images

High demand for meat means a higher need for
grain to feed livestock. The soybeans used to feed
these Chinese-produced pigs is imported from
Brazil and the United States because China does not
produce enough grain to feed all its livestock.

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SEctIon 3.1 The Global Food Crisis—FeedinG nine billion

the green revolution Borlaug started
had nothing to do with the eco-friendly
green label in vogue today. With its use
of synthetic fertilizers and pesticides
to nurture vast fields of the same crop,
a practice known as monoculture, this
new method of industrial farming was
the antithesis of today’s organic trend.
rather, William S. Gaud, then admin-
istrator of the u.S. Agency for Interna-
tional Development, coined the phrase
in 1968 to describe an alternative to
russia’s red revolution, in which work-
ers, soldiers, and hungry peasants had
rebelled violently against the tsarist
government. the more pacifying green
revolution was such a staggering suc-
cess that Borlaug won the nobel Peace
Prize in 1970.

today, though, the miracle of the green
revolution is over in Punjab: Yield
growth has essentially flattened since

the mid-1990s. overirrigation has led to steep drops in the water table, now tapped by 1.3 mil-
lion tube wells, while thousands of hectares of productive land have been lost to salinization
[soils becoming salty] and waterlogged soils. Forty years of intensive irrigation, fertilization, and
pesticides have not been kind to the loamy gray fields of Punjab. nor, in some cases, to the people
themselves. [. . .]

“the green revolution has brought us only downfall,” says Jarnail Singh, a retired school-
teacher in Jajjal village. “It ruined our soil, our environment, our water table. used to be we
had fairs in villages where people would come together and have fun. now we gather in medi-
cal centers. the government has sacrificed the people of Punjab for grain.”

others, of course, see it differently. rattan Lal, a noted soil scientist at ohio State who gradu-
ated from Punjab Agricultural university in 1963, believes it was the abuse—not the use—of
green revolution technologies that caused most of the problems. that includes the overuse of
fertilizers, pesticides, and irrigation and
the removal of all crop residues from the
fields, essentially strip-mining soil nutri-
ents. “I realize the problems of water
quality and water withdrawal,” says Lal.
“But it saved hundreds of millions of
people. We paid a price in water, but the
choice was to let people die.”

In terms of production, the benefits of the
green revolution are hard to deny. India
hasn’t experienced famine since Borlaug
brought his seeds to town, while world
grain production has more than doubled.

Consider This
During the mid-1960s, rising global popu-
lations, stagnant grain production, and
specific crises such as the Bengal Famine
prompted agricultural science to launch
the green revolution. Describe the benefits
and drawbacks of the green revolution,
particularly as seen in India.

AP Photo

While it eased hunger, the green revolution also
created a number of other problems, including the
overuse of fertilizers, pesticides, and irrigation that
depleted nutrients from the soil. Here, an Indian
man stands in a “bumper crop” of wheat during the
green revolution.

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SEctIon 3.1 The Global Food Crisis—FeedinG nine billion

Some scientists credit increased rice yields alone with the existence of 700 million more peo-
ple on the planet.

The Next Green Revolution
Many crop scientists and farmers believe the solution to our current food crisis lies in a sec-
ond green revolution, based largely on our newfound knowledge of the gene. Plant breeders
now know the sequence of nearly all of the 50,000 or so genes in corn and soybean plants
and are using that knowledge in ways that were unimaginable only four or five years ago,
says robert Fraley, chief technology officer for the agricultural giant Monsanto. Fraley is con-
vinced that genetic modification, which allows breeders to bolster crops with beneficial traits
from other species, will lead to new varieties with higher yields, reduced fertilizer needs, and
drought tolerance—the holy grail for the past decade. He believes biotech will make it pos-
sible to double yields of Monsanto’s core crops of corn, cotton, and soybeans by 2030. “We’re
now poised to see probably the greatest period of fundamental scientific advance in the his-
tory of agriculture.” [. . .]

But is a reprise of the green revolution—with the traditional package of synthetic fertilizers,
pesticides, and irrigation, supercharged by genetically engineered seeds—really the answer
to the world’s food crisis? Last year a massive study called the “International Assessment
of Agricultural Knowledge, Science and technology for Development” concluded that the
immense production increases brought about by science and technology in the past 30 years
have failed to improve food access for many of the world’s poor. the six-year study, initiated
by the World Bank and the un’s Food and Agriculture organization and involving some 400
agricultural experts from around the globe, called for a paradigm shift in agriculture toward
more sustainable and ecologically friendly practices that would benefit the world’s 900 mil-
lion small farmers, not just agribusiness.

the green revolution’s legacy of tainted soil and depleted aquifers is one reason to look for
new strategies. So is what author and university of california, Berkeley, professor Michael
Pollan calls the Achilles heel of current green revolution methods: a dependence on fossil
fuels. natural gas, for example, is a raw material for nitrogen fertilizers. “the only way you
can have one farmer feed 140 Americans is with monocultures. And monocultures need lots
of fossil-fuel-based fertilizers and lots of fossil-fuel-based pesticides,” Pollan says. “that only
works in an era of cheap fossil fuels, and that era is coming to an end. Moving anyone to a
dependence on fossil fuels seems the height of irresponsibility.”

So far, genetic breakthroughs that would free green revolution crops from their heavy depen-
dence on irrigation and fertilizer have proved elusive. Engineering plants that can fix their
own nitrogen or are resistant to drought “has proven a lot harder than they thought,” says
Pollan. Monsanto’s Fraley predicts his company will have drought-tolerant corn in the
u.S. market by 2012. But the increased yields promised during drought years are only 6 to
10 percent above those of standard drought-hammered crops.[*]

* notE: Monsanto has, in fact, received clearance from the u.S. Department of Agriculture (uSDA) to market
its drought-tolerant corn in the united States. However, early trials of the crop were not very successful and it
remains to be seen whether it will be adopted to any significant degree by farmers (http://e360.yale.edu/digest
/drought-resistant_gm_corn_poses_limited_risk_-_or_benefit_us_says/2941/).

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http://e360.yale.edu/digest/drought-resistant_gm_corn_poses_limited_risk_-_or_benefit_us_says/2941/

SEctIon 3.1 The Global Food Crisis—FeedinG nine billion

A Change in Focus—Agroecology
And so a shift has already begun to small, underfunded projects scattered across Africa and
Asia. Some call it agroecology, others sustainable agriculture, but the underlying idea is revo-
lutionary: that we must stop focusing on simply maximizing grain yields at any cost and con-
sider the environmental and social impacts of food production. Vandana Shiva is a nuclear
physicist turned agroecologist who is India’s harshest critic of the green revolution. “I call it
monocultures of the mind,” she says. “they just look at yields of wheat and rice, but overall
the food basket is going down. there were 250 kinds of crops in Punjab before the green
revolution.” Shiva argues that small-scale, biologically diverse farms can produce more food
with fewer petroleum-based inputs. Her research has shown that using compost instead of
natural-gas-derived fertilizer increases organic matter in the soil, sequestering carbon and
holding moisture—two key advantages for farmers facing climate change. “If you are talking
about solving the food crisis, these are the methods you need,” adds Shiva.

In northern Malawi one project is getting many of the same results as the Millennium Villages
project, at a fraction of the cost. there are no hybrid corn seeds, free fertilizers, or new roads
here in the village of Ekwendeni. Instead the Soils, Food and Healthy communities (SFHc)
project distributes legume seeds, recipes, and technical advice for growing nutritious crops
like peanuts, pigeon peas, and soybeans, which enrich the soil by fixing nitrogen while also
enriching children’s diets. the program began in 2000 at Ekwendeni Hospital, where the staff
was seeing high rates of malnutrition. research suggested the culprit was the corn monocul-
ture that had left small farmers with poor yields due to depleted soils and the high price of
fertilizer. [. . .]

Which is why the project’s research coordinator, rachel Bezner Kerr, is alarmed that big-
money foundations are pushing for a new green revolution in Africa. “I find it deeply dis-
turbing,” she says. “It’s getting farmers to rely on expensive inputs produced from afar that
are making money for big companies rather than on agroecological methods for using local
resources and skills. I don’t think that’s the solution.”

The Challenge Ahead
regardless of which model prevails—agriculture as a diverse ecological art, as a high-tech
industry, or some combination of the two—the challenge of putting enough food in nine bil-
lion mouths by 2050 is daunting. two billion people already live in the driest parts of the
globe, and climate change is projected to slash yields in these regions even further. no mat-
ter how great their yield potential, plants still need water to grow. And in the not too distant
future, every year could be a drought year for much of the globe.

new climate studies show that extreme heat waves, such as the one that withered crops and
killed thousands in western Europe in 2003, are very likely to become common in the tropics
and subtropics by century’s end. Himalayan glaciers that now provide water for hundreds of
millions of people, livestock, and farmland in china and India are melting faster and could
vanish completely by 2035. In the worst-case scenario, yields for some grains could decline
by 10 to 15 percent in South Asia by 2030. Projections for southern Africa are even more
dire. In a region already racked by water scarcity and food insecurity, the all-important corn
harvest could drop by 30 percent—47 percent in the worst-case scenario. All the while the

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SEctIon 3.2 EnVIronMEntAL IMPActS oF conVEntIonAL AGrIcuLturE

population clock keeps ticking, with a net of 2.5 more mouths to feed born every second. that
amounts to 4,500 more mouths in the time it takes you to read this article. [. . .]

Adapted from Bourne, J. K., Jr. (2009). The Global Food Crisis: The End of Plenty. national Geographic Magazine.
Retrieved from http://ngm.nationalgeographic.com/print/2009/06/cheap-food/bourne-text. Joel K. Bourne/
National Geographic Creative. Used by permission.

Apply Your Knowledge
on average, Americans consume approximately 270 pounds of meat per person per year,
among the highest rates of consumption in the world and often 20 times as much as people in
some poorer countries. As made clear in this reading, a meat-based diet requires significant
grain production as well as massive inputs of energy and water. review the chart found on
this web page (http://www.npr.org/blogs/thesalt/2012/06/27/155527365/visualizing-a
-nation-of-meat-eaters) to get a sense of how much grain, water, land, and fossil fuel energy
is required to make one quarter-pound hamburger. next, estimate how many hamburgers
you eat per year (if you don’t eat meat or burgers, then do this calculation for someone you
know who does). Based on that estimate and the figures provided on the web page, calculate
how much grain, water, land, and energy is required to make this level of hamburger con-
sumption possible.

3.2 Environmental Impacts of Conventional Agriculture
Our modern or conventional agricultural system produces a staggering amount of food at rela-
tively low costs to consumers. Americans spend as little as 7 percent of their income on food,
over half of what we spent a generation ago and far less than what people in other countries
spend to feed themselves. Despite this success, there are concerns that conventional approaches
to agriculture—which emphasize heavy inputs of energy, water, and synthetic fertilizers and
pesticides—could impose environmental and health costs on society that are not reflected in
the prices we pay for food. This briefing by staff of the U.S. Department of Agriculture Economic
Research Service reviews some of the major environmental issues associated with conventional
agricultural production.

The following report highlights some of the key areas of concern when assessing the environ-
mental impacts of agriculture, which include soil erosion, water pollution, air pollution, and
habitat destruction. Modern agricultural techniques involve extensive plowing and manipula-
tion of soils, and this can result in soil erosion by wind and rain. Eroded soils can reduce farmland
fertility, pollute local waterways, and carry fertilizers and pesticides into surface waters. When
nitrogen and phosphorous from agricultural fertilizers or animal manure wash into rivers and
other bodies of water, they can promote the growth of algae, a process known as eutrophica-
tion. This can lead to decreased oxygen levels in the water and the death of many fish and other
aquatic organisms. Pesticide runoff, pesticides leaching into groundwater, and pesticide residues
on food crops and fruit can also pose health concerns. Agriculture also results in air pollution
from a number of sources, including particulate matter from wind erosion and smog formation
from agricultural chemicals and emissions of pollutants from farm equipment. Lastly, agricul-
ture often involves the conversion of natural habitats to human uses, and this can have negative
impacts on wildlife and biodiversity (as will be discussed in Chapter 4). Given the seriousness of

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http://ngm.nationalgeographic.com/print/2009/06/cheap-food/bourne-text

http://www.npr.org/blogs/thesalt/2012/06/27/155527365/visualizing-a-nation-of-meat-eaters

SEctIon 3.2 EnVIronMEntAL IMPActS oF conVEntIonAL AGrIcuLturE

these impacts it’s clear why the debate over biotechnology and genetic engineering (section 3.3)
takes on such importance. Advocates of this approach argue that it will help address many of
agriculture’s environmental impacts, but critics argue that it might, in fact, make things worse.

By Staff of the U.S. Department of Agriculture Economic Research Service
over 440 million acres (19.5 percent of land) is dedicated to growing crops in the u.S., and
another 587 million acres (26 percent) is in pasture and range, largely used for domestic live-
stock production. Agricultural activities on these lands produce a plentiful, diverse, and rela-
tively inexpensive supply of food and fiber for people here at home and abroad. However, agri-
cultural production practices can degrade the environment. transformation of undisturbed
land to crop production can diminish habitat for wildlife. Soil erosion, nutrient and pesticide
runoff, and irrigation can pollute the air and water, degrade soil quality, and diminish water
supplies. the extent and degree of the environmental problems associated with agriculture
vary widely across the country. concern over these problems has given rise to local, State, and
Federal conservation and environmental policies and programs to address them.

Soil Quality
Soil, as a plant-growing medium, is the key resource in crop production. Soil supports the
fundamental physical, chemical, and biological processes that must take place in order for
plants to grow [. . .]. Soil can also function as a “degrader” or “immobilizer” [the ability to
break down or hold in place pollutants so that they do not enter groundwater supplies] of
agricultural chemicals, wastes, or other potential pollutants, and can mitigate climate change
by sequestering [absorbing] carbon from the atmosphere [. . .]. How well soil performs these
functions depends on soil quality. How soil is managed has a major impact on soil quality, and
on the potential for various pollutants to leave the field and affect other resources.

Soil quality can be defined as the capacity of a specific kind of soil to function, within natu-
ral or managed ecosystem boundaries, to sustain plant and animal productivity, maintain or
enhance water and air quality, and support human health and habitation. Soil quality depends
on attributes such as the soil’s texture, depth, permeability, biological activity, capacity to
store water and nutrients, and organic matter content. Soil quality can be maintained or
enhanced through the use of appropriate crop production technologies and related resource
management systems. Poorly managed fields can lead to soil degradation through three pro-
cesses: physical degradation, such as via wind and water erosion and soil compaction; chemi-
cal degradation, such as toxification [conversion of chemicals into toxic forms], acidification,
and salinization; and biological degradation, such as loss of organic matter and decline in the
activity of soil fauna. Poor management can also increase runoff of nutrients and pesticides
to surface and groundwater systems. thus, soil degradation can have both direct and indirect
negative effects on agricultural productivity and the environment. Even on high-quality soils,
overuse of chemical inputs can result in soil toxicity and water pollution.

Water Quality
Agriculture is widely believed to have significant impacts on water quality. While no compre-
hensive national study of agriculture and water quality has been conducted, the magnitude of
the impacts can be inferred from several water quality assessments. A general assessment of
water quality is provided by EPA’s 2002 Water Quality Inventory. Based on State assessments
of 19 percent of river and stream miles, 37 percent of lake acres, and 35 percent of estuarine

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square miles, EPA concluded that agriculture is the leading source of pollution in 37 percent
of river miles, 30 percent of lake acres (excluding the Great Lakes), and 8 percent of estuarine
waters found to be water-quality impaired, in that they do not support designated uses. this
makes agriculture the leading source of impairment in the nation’s rivers and lakes, and a
minor source of impairment in estuaries. Agriculture’s contribution has remained relatively
unchanged over the past decade.

Major Agricultural Pollutants
Sediment [naturally occurring material that can wash off of fields] is the largest contami-
nant of surface water by weight and volume, and is identified by States as the leading pol-
lution problem in rivers and streams and the fourth leading problem in lakes. Sediment in
surface water is largely a result of soil erosion, which is influenced by soil properties and
the production practices farmers choose. Sediment buildup reduces the useful life of reser-
voirs. Sediment can clog roadside ditches and irrigation canals, block navigation channels,
and increase dredging costs. By raising streambeds and burying streamside wetlands, sedi-
ment increases the probability and severity of floods. Suspended sediment can increase the
cost of water treatment for municipal and industrial water uses. Sediment can also destroy
or degrade aquatic wildlife habitat, reducing diversity and damaging commercial and recre-
ational fisheries.

nitrogen and phosphorus [two critical plant nutrients] are important crop nutrients, and
farmers apply large amounts to cropland each year. they can enter water resources through
runoff and leaching [percolate through the ground]. the major concern for surface-water
quality is the promotion of algae growth (known as eutrophication), which can result in
decreased oxygen levels, fish kills, clogged pipelines, and reduced recreational opportunities.
the u.S. Geological Survey (uSGS) has found that high concentrations of nitrogen in agricul-
tural streams are correlated with nitrogen inputs from fertilizers and manure used on crops
and from livestock waste. EPA reported in its Water Quality Inventory that nutrient pollution
is the leading cause of water quality impairment in lakes, and a major cause of oxygen deple-
tion in estuaries. [. . .]

Eutrophication and hypoxia (low oxygen
levels) in the northern Gulf of Mexico
have been linked to nitrogen loadings
from the Mississippi river. Agricultural
sources (fertilizer, soil inorganic nitro-
gen, and manure) are estimated to con-
tribute about 71 percent of the nitrogen
loads entering the Gulf from the Mis-
sissippi Basin, and 80 percent of phos-
phorus loads. the Gulf of Mexico is not
the only coastal area affected by nutri-
ents. recent research by the national
oceanographic and Atmospheric Admin-
istrations has found that 65 percent of
assessed estuaries had moderate to high
overall eutrophic conditions, caused pri-
marily by nitrogen enrichment.

Consider This
nitrogen and phosphorous are fertilizers,
and when they enter water bodies like lakes
and streams, they promote the growth of
aquatic plants and algae. Why is this a prob-
lem? Design an experiment, using the basic
principles of the scientific method, to test
how additions of different amounts of nitro-
gen and phosphorous might affect water
quality and wildlife in a body of water.

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Farmers apply a wide variety of pesticides to control insects (insecticides), weeds (herbi-
cides), fungus (fungicides), and other problems. Well over 500 million pounds (active ingredi-
ent) of pesticides have been applied annually on farmland since the 1980s, and certain chemi-
cals can travel far from where they are applied. Pesticide residues reaching surface-water
systems may harm freshwater and marine organisms, damaging recreational and commercial
fisheries. Pesticides in drinking water supplies may also pose risks to human health. Pesticide
concentrations exceeded one or more human-health benchmarks in about 10 percent of agri-
cultural streams examined by uSGS as part of the national Water Quality Assessment Pro-
gram, and in about 1 percent of sampled wells used for drinking water in agricultural areas.

Some irrigation water applied to crop-
land may run off the field into ditches
and receiving waters. these irrigation
return flows often carry dissolved
salts as well as nutrients and pesti-
cides into surface or ground water.
Increased salinity levels in irrigation
water can reduce crop yields or dam-
age soils such that some crops can no
longer be grown. Increased concen-
trations of naturally occurring toxic
minerals—such as selenium, molyb-
denum, and boron—can harm aquatic
wildlife and impair water-based rec-
reation. Increased levels of dissolved
solids in public drinking water supplies
can increase water treatment costs,
force the development of alternative
water supplies, and reduce the lifes-
pans of water-using household appli-
ances. the possibility of pathogens
contaminating water supplies and rec-
reation waters is a continuing concern. Bacteria are the largest source of impairment in rivers
and streams, according to EPA’s water quality inventory. Potential sources include inadequately
treated human waste, wildlife, unconfined livestock, and animal operations. Diseases from
micro-organisms in livestock waste can be contracted through direct contact with contami-
nated water, consumption of contaminated drinking water, consumption of crops irrigated with
contaminated water, or consumption of contaminated shellfish. [. . .]

Air Quality
Ever since farmers began raising animals and cultivating crops, agricultural production prac-
tices have generated a variety of substances that enter the atmosphere with the potential of
creating health and environmental problems. the relationship between agriculture and air
quality became a national issue in the 1930s with the severe dust storms of the Dust Bowl.
Although dust storms of this magnitude no longer occur in the united States, soil particulates,
farm chemicals, and odor from livestock are still carried in the air we breathe. these emis-
sions can harm human health and pollute the environment. Air quality in most rural areas is
not a cause for concern, but there are some farming communities where ozone and particu-
lates have impaired air quality to the same extent as in urban areas.

Jan Sochor/age fotostock/SuperStock

A farmer wearing a full-body protective suit sprays
crops with pesticides. The level of protection is
warranted; many pesticides are known carcinogens,
teratogens, and endocrine disruptors for animals
and humans.

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SEctIon 3.2 EnVIronMEntAL IMPActS oF conVEntIonAL AGrIcuLturE

Ammonia is a gas and one of the most abundant nitrogen-containing compounds emitted to
the atmosphere. Animal farming systems contribute about 50 percent of the total anthropo-
genic [man-made] emissions of ammonia into the atmosphere in the u.S. Ammonia is a health
hazard to humans and animals in high concentrations. once in the atmosphere, ammonia is
rapidly converted to ammonium particles by reactions with acidic compounds such as nitric
acid and sulfuric acid found in ambient aerosols [small, airborne particles]. these ammonium
particles can be carried long distances in the atmosphere and contribute to fine particulate
pollution and haze. Ammonium is redeposited to the earth’s surface by both wet and dry
deposition [the process by which particles deposit to the ground; wet refers to rain and dry
usually to gravity] contributing to eutrophication of water resources.

nitrous oxide is another nitrogen compound of concern. It is a greenhouse gas and contrib-
utes to ozone depletion. nitrous oxide forms primarily in the soil during the microbial pro-
cesses of nitrification [conversion of ammonia to nitrite] and denitrification [conversion of
nitrate to nitrogen]. Agricultural sources include manure from livestock farming and com-
mercial fertilizer. Agriculture contributes about 72 percent of total anthropogenic emissions
of nitrous oxide in the u.S., mostly from the fertilization of cropland.

Methane is an important greenhouse gas. It is produced by microbial degradation of organic
matter under anaerobic conditions. the agricultural sector is the largest anthropogenic
source, with livestock production being the major component. Enteric fermentation (within
the stomachs of cattle, sheep, goats and other ruminants) and manure management contrib-
ute 27 percent of methane emissions in the united States.

carbon dioxide is the primary greenhouse gas emitted in the u.S., mostly from the combustion
of fossil fuels. carbon dioxide is also a primary input in plant growth. Agriculture can seques-
ter [store] carbon in soils and biomass, thus offsetting greenhouse gas emissions. carbon
entering the soil is stored primarily as soil organic matter. Agricultural soils sequestered an
estimated 12.4 million metric tons carbon equivalent in 2004, less than 1 percent of u.S. emis-
sions. Studies indicate that it may be technically possible to sequester an additional 89–318
million metric tons of carbon annually on u.S. croplands and grazing lands through various
management practices, such as conservation tillage, crop rotations, and fertilizer manage-
ment. Shifting cropland to grasslands or forest could increase sequestration even more.

Particulates from agriculture result from a variety of activities. Wind erosion can carry soil
particles directly into the atmosphere. Many areas west of the Mississippi river experience
low average rainfall, frequent drought, and relatively high wind velocities. these conditions,
when combined with fine soils, sparse vegetative cover, and agricultural activity, make some
western regions susceptible to wind erosion.

Wind erosion can produce short-term levels of particulate pollution in rural areas that exceed
urban levels. Particulates from wind erosion can impose costs on those living in affected
areas, including cleaning and maintenance of businesses and households, damage to nonfarm
machinery, and adverse effects on health. Another source of particulates is open-field burn-
ing. open-field burning is used as a means of removing crop residue after harvest and control-
ling disease, weeds, and pests. Diesel engines from farm equipment and irrigation pumps are
also a source of particulates.

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A source of fine particulates (particles smaller than 2.5 microns, also known as PM2.5) is gas-
eous emissions of ammonia and nitrogen oxides (nox, or nitric oxide, and nitrogen dioxide).
Ammonia and nox in the atmosphere react with other compounds to form fine particulates,
such as ammonium. Fine particulates pose a health risk because they can be inhaled deep into
lungs. Fine particulates are also a source of haze, which detracts from views in many popular
national parks.

the atmosphere is now recognized as a major pathway by which pesticides can be trans-
ported and deposited far from their point of use. Pesticides can enter the atmosphere directly
from the spray cloud during application, from evaporation after application, and attached
to windborne soil particles. As much as 80 percent of some pesticide applications evapo-
rate. And many of these pesticides across different chemical groups have been detected in the
atmosphere. the u.S. Geological Survey found that the most frequently detected pesticides in
the atmosphere are DDt, methidathion, diazinon, heptachlor, malathion, and dieldrin. Even
though some of these have been banned for years, they continue to be detected. [. . .]

Wildlife Habitat
Habitat is a combination of environmental factors that provides the food, water, cover, and
space that a living organism needs to survive and reproduce. Agricultural land use can benefit
some species, harm others, and sometimes do both. Potentially harmful effects of farming
include plowing up habitat, farming riparian [along the banks of a river or stream] buffers,
fragmenting habitat, diverting water for irrigation, and diffusing agricultural chemicals into
the environment. In addition, specialization in agriculture reduces landscape diversity by cre-
ating more of a monoculture [growing only one crop]. this reduces the presence of ecological
niches, which can limit wildlife populations and biodiversity on farms. Historically, the con-
version of native forests, prairies, and wetlands to cropland has diminished wildlife. Habitat
loss associated with agricultural practices on over 400 million acres of cropland has been
identified as a primary factor depressing wildlife populations in north America. Agriculture
is thought to affect the survival of 380 of the 663 species listed by the Federal Government as
threatened or endangered in the conterminous 48 States.

Agriculture’s negative effects on wildlife need not be permanent. u.S. agriculture is in a unique
position with respect to the nation’s wildlife resources. the management of land now con-
trolled by u.S. farms and ranches can play a major role in protecting and enhancing the nation’s
wildlife. In 2002, private farms accounted for 41 percent of all u.S. land, including 434 million
acres of cropland and 395 million acres of pasture and range. Farms also account for 76 mil-
lion acres of forest and woodland, and 17 million acres of nonfederal wetlands. Different types
of habitat can be restored or improved through conservation on agricultural lands.

Grassland Habitat
Grasslands constitute the largest land cover on America’s private lands. Privately owned grass-
lands and shrub lands (including tribal) cover more than 395 million acres in the united States.
these lands contribute significantly to the economies of many regions, provide biodiversity of

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SEctIon 3.2 EnVIronMEntAL IMPActS oF conVEntIonAL AGrIcuLturE

plant and animal populations, and play
a key role in environmental quality.
Grasslands directly support the live-
stock industry. they also provide habi-
tat for many wildlife species, reduce
the potential for flooding, control sedi-
ment loadings in streams and other
water bodies, and provide ecological
benefits such as nutrient cycling, stor-
age of atmospheric carbon, and water
conservation. Grasslands also improve
the aesthetic character of the land-
scape, provide scenic vistas and open
space, provide recreational opportu-
nities, and protect the soil from water
and wind erosion.

Large expanses of grassland acreage
are annually threatened by conversion
to other land uses such as cropland

and urban development. About half of all grasslands in the u.S. have been lost since settle-
ment, much due to conversion to agricultural uses.

Wetland Habitat
Wetlands are complex ecosystems that provide many ecological functions that are valued by
society. they take many forms, including prairie potholes, bottomland hardwood swamps,
coastal salt marshes, and playa wetlands. Wetlands are known to be the most biologically
productive landscapes in temperate regions. More than one-third of the united States’ threat-
ened and endangered species live only in wetlands, and nearly half use wetlands at some
point in their lives. Most freshwater fish depend on wetlands at some stage of their lives.
Many bird species are dependent on wetlands for either resting places during migration,
nesting or feeding grounds, or cover from predators. Wetlands are also critical habitat for
many amphibians and fur bearing mammals. Besides supporting wildlife, wetlands also con-
trol water pollution and flooding, protect
the water supply, and provide recreation.

When the country was first settled there
were 221–224 million acres of wetlands
in the continental u.S. Since then, about
half have been drained and converted to
other uses, nearly 85 percent for agricul-
tural uses. currently, there are about 111
million acres of wetlands on nonfederal
lands. About 15 percent are on agricul-
tural lands (cropland, pastureland, and
rangeland).

Consider This
Many people think of wetlands just as
swamps, and swamps as places of pesti-
lence and disease. Why does it matter then
that tens of millions of acres of wetlands
have been converted to agricultural uses in
the united States?

. Roger Calger/iStock/Thinkstock

Grasslands support the livestock industries of the
surrounding communities and contribute to the
overall environmental quality of a region.

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Apply Your Knowledge
It’s clear from this reading that conventional agricultural practices impose significant costs on
society in the form of decreased water quality, air quality, and wildlife habitat. For the most
part these costs are not counted or factored into the price of the food we buy, although they
are borne by society in other ways such as through higher taxes to pay for water treatment
and health care costs. Environmental scientists and economists refer to these kinds of costs as
external costs. Develop an inventory of the major environmental impacts of conventional agri-
culture and how they might impose external costs on society. next, ask yourself who might be
paying these external costs and how. Finally, ask yourself how our approach to agriculture might
change if major agricultural producers were forced to pay directly for these external costs.

Riparian Habitat
riparian areas are the zones along water bodies that serve as interfaces between terrestrial
and aquatic ecosystems. riparian ecosystems generally compose a minor proportion of the
landscape, but they are typically more structurally diverse and more productive from a wild-
life perspective than adjacent upland areas. this is especially true in the arid West. Studies
in the Southwest show that riparian areas support a higher breeding diversity of birds than
all other western habitats combined. In Arizona and new Mexico, at least 80 percent of all
animals use riparian areas at some stage of their lives. Western riparian habitats contain the
highest non-colonial avian breeding densities in north America.

riparian zones also support productive aquatic habitat. they stabilize streambanks, thus
reducing streambank erosion and sedimentation. Detritus [non-living organic material, such
as fallen leaves] from streamside vegetation provides energy to the stream ecosystem. Veg-
etation also provides shade, preventing extreme temperature swings that are detrimental to
healthy stream ecosystems. riparian areas also filter out sediment, nutrients, and pesticides
in runoff, thereby protecting water quality.

no comprehensive national inventory has been completed on the status and trends of ripar-
ian areas. However, nrcS estimates that the conterminous u.S. originally contained 75–100
million acres of riparian habitats and that between 25 and 35 million acres remain.

Implications for Policy
Agriculture has wide ranging impacts on environmental resources. Because of this, it also
has the capacity to provide a wide range of environmental services. understanding the links
between agriculture and environmental quality enhances our ability to design programs that
best meet the needs of producers and those who value the services the environment can
provide.

Adapted from USDA Economic Research Service. 2009 (updated). Environmental Interactions with Agricultural
Production: Background. Retrieved from http://www.ers.usda.gov/Briefing/AgAndEnvironment/background.htm

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SEctIon 3.3 The debaTe over GeneTiCally ModiFied (GM) Foods

3.3 The Debate Over Genetically Modified (GM) Foods
The opening article for this chapter asked what the next agricultural revolution would look
like—would it be one focused on new forms of genetic engineering or one based on the concept
of agroecology or sustainable agriculture. In the following article, Natasha Gilbert of the journal
nature reviews some of the issues swirling around the debate over genetically modified (GM)
crops. She concludes by stating that “stories, in favour of or against GM crops, will always miss
the bigger picture, which is nuanced, equivocal and undeniably messy.” Regardless of that cau-
tionary plea, the debate over GM crops remains one of the most contentious and emotional in
the field of environmental science.

Unlike the first green revolution, which was achieved mainly through traditional plant-breeding
approaches, genetic modification of crops represents a fundamentally new technology. Tradi-
tional plant breeding sought to cross-breed or combine traits from the same plant types to pro-
duce a new and better variety. For example, a rice plant that produced a lot of grain but blew
over easily in the wind could be cross-bred with another rice plant that produced less grain
but had a stronger stem and could withstand the wind. The resulting rice plant, after repeated
breeding, would feature both desirable traits—high grain production and stoutness—in a single
seed. In contrast, genetic modification works by removing genetic material from one organism
and inserting it into the DNA of another, often in “novel” ways or in combinations that would
never occur in nature (for example, inserting fish genes into a tomato plant).

As with traditional plant breeding, genetic engineering seeks to develop plants that feature cer-
tain desirable traits. These could include developing plants that feature “input” traits such as
resistance to pests or resistance to fungus and disease or plants that can withstand frost or
drought conditions. This could also include developing “output” traits such as plants that have
much higher nutritional content than traditional varieties.

The use of genetically engineered crops has grown rapidly in countries such as the United States,
especially for soybeans, corn, and cotton where GM crops make up between 70 and 90 percent of
total production (Figure 3.1). This rapid growth has raised concerns about the environmental,
health, and economic impacts of widespread use of genetically engineered crops. As you review
this reading consider the ways in which scientists might make use of the scientific method both
to develop new genetically modified crops as well as to test whether these crops might have
negative impacts on human health or the environment. Also be prepared to test your own beliefs
on this subject in an assignment at the end of this section.

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SEctIon 3.3 The debaTe over GeneTiCally ModiFied (GM) Foods

Figure 3.1: Genetically engineered crops

the adoption of genetically engineered crops, including herbicide-tolerant (Ht) crops and insect-
resistant crops engineered with Bacillus thuringiensis, has increased significantly since 1996.

Based on data from USDA. Retrieved from http://www.ers.usda.gov/media/185551/biotechcrops.html

By Natasha Gilbert
In the pitched debate over genetically modified (GM) foods and crops, it can be hard to see
where scientific evidence ends and dogma and speculation begin. In the nearly 20 years since
they were first commercialized, GM crop technologies have seen dramatic uptake. Advocates
say that they have increased agricultural production by more than uS$98 billion and saved an
estimated 473 million kilograms of pesticides from being sprayed. But critics question their
environmental, social and economic impacts.

researchers, farmers, activists and GM seed companies all stridently promote their views, but
the scientific data are often inconclusive or contradictory. complicated truths have long been
obscured by the fierce rhetoric. “I find it frustrating that the debate has not moved on,” says
Dominic Glover, an agricultural socioeconomist at Wageningen university and research cen-
tre in the netherlands. “the two sides speak different languages and have different opinions
on what evidence and issues matter,” he says.

Here, Nature takes a look at three pressing questions: are GM crops fuelling the rise of
herbicide-resistant ‘superweeds’? Are they driving farmers in India to suicide? And are the
foreign transgenes in GM crops spreading into other plants? these controversial case stud-
ies show how blame shifts, myths are spread and cultural insensitivities can inflame debate.

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Herbicide-tolerant Soybeans

Herbicide-tolerant Cotton

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Insect-resistant Cotton (Bacillus thuringiensis)

Insect-resistant Corn (Bacillus thuringiensis)

Year

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SEctIon 3.3 The debaTe over GeneTiCally ModiFied (GM) Foods

GM Crops Have Bred Superweeds: True
Jay Holder, a farming consultant in Ashburn, Georgia, first noticed Palmer amaranth (Amaran-
thus palmeri) in a client’s transgenic cotton fields about five years ago. Palmer amaranth is a
particular pain for farmers in the southeastern united States, where it outcompetes cotton for
moisture, light and soil nutrients and can quickly take over fields.

Since the late 1990s, uS farmers had widely adopted GM cotton engineered to tolerate the
herbicide glyphosate, which is marketed as roundup by Monsanto in St Louis, Missouri. the
herbicide–crop combination worked spectacularly well—until it didn’t. In 2004, herbicide-
resistant amaranth was found in one county in Georgia; by 2011, it had spread to 76. “It got
to the point where some farmers were losing half their cotton fields to the weed,” says Holder.

Some scientists and anti-GM groups warned that GM crops, by encouraging liberal use of
glyphosate, were spurring the evolution of herbicide resistance in many weeds. twenty-four
glyphosate-resistant weed species have been identified since roundup-tolerant crops were
introduced in 1996. But herbicide resistance is a problem for farmers regardless of whether
they plant GM crops. Some 64 weed species are resistant to the herbicide atrazine, for exam-
ple, and no crops have been genetically modified to withstand it.

Still, glyphosate-tolerant plants could be considered victims of their own success. Farm-
ers had historically used multiple herbicides, which slowed the development of resistance.
they also controlled weeds through ploughing and tilling—practices that deplete topsoil and
release carbon dioxide, but do not encourage resistance. the GM crops allowed growers to
rely almost entirely on glyphosate, which is less toxic than many other chemicals and kills a
broad range of weeds without ploughing. Farmers planted them year after year without rotat-
ing crop types or varying chemicals to deter resistance.

Glyphosate-resistant weeds have now been found in 18 countries worldwide, with signifi-
cant impacts in Brazil, Australia, Argentina and Paraguay, says Ian Heap, director of the Inter-
national Survey of Herbicide resistant Weeds, based in corvallis, oregon. And Monsanto has
changed its stance on glyphosate use, now recommending that farmers use a mix of chemical
products and ploughing. But the company stops short of acknowledging a role in creating
the problem.

on balance, herbicide-resistant GM crops are less damaging to the environment than con-
ventional crops grown at industrial scale. A study by PG Economics, a consulting firm in
Dorchester, uK, found that the introduction of herbicide-tolerant cotton saved 15.5 million
kilograms of herbicide between 1996 and 2011, a 6.1% reduction from what would have
been used on conventional cotton. And GM crop technology delivered an 8.9% improvement
to the environmental impact quotient—a measure that considers factors such as pesticide
toxicity to wildlife—says Graham Brookes, co-director of PG Economics and a co-author of the
industry-funded study, which many scientists consider to be among the field’s most extensive
and authoritative assessments of environmental impacts.

the question is how much longer those benefits will last. So far, farmers have dealt with the
proliferation of resistant weeds by using more glyphosate, supplementing it with other herbi-
cides and ploughing. A study by David Mortensen, a plant ecologist at Pennsylvania State uni-
versity in university Park, predicts that total herbicide use in the united States will rise from
around 1.5 kilograms per hectare in 2013 to more than 3.5 kilograms per hectare in 2025 as
a direct result of GM crop use.

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SEctIon 3.3 The debaTe over GeneTiCally ModiFied (GM) Foods

to offer farmers new weed-control strategies, Monsanto and other biotechnology compa-
nies, such as Dow AgroSciences, based in Indianapolis, Indiana, are developing new herbi-
cide-resistant crops that work with different chemicals, which they expect to commercialize
within a few years.

Mortensen says that the new technologies will lose their effectiveness as well. But abandon-
ing chemical herbicides completely is not a viable solution, says Jonathan Gressel, a weed
scientist at the Weizmann Institute of Science in rehovot, Israel. using chemicals to control
weeds is still more efficient than ploughing and tilling the soil, and is less environmentally
damaging. “When farmers start to use more sustainable farming practices together with mix-
tures of herbicides they will have fewer problems,” he says.

GM Cotton Has Driven Farmers to Suicide: False
During an interview in March, Vandana Shiva, an environmental and feminist activist from
India, repeated an alarming statistic: “270,000 Indian farmers have committed suicide since
Monsanto entered the Indian seed market,” she said. “It’s a genocide.”

the claim, based on an increase in total suicide rates across the country in the late 1990s,
has become an oft-repeated story of corporate exploitation since Monsanto began selling GM
seed in India in 2002.

Bt cotton, which contains a gene from the bacterium Bacillus thuringiensis to ward off cer-
tain insects, had a rough start. Seeds initially cost five times more than local hybrid varieties,
spurring local traders to sell packets containing a mix of Bt and conventional cotton at lower
prices. the sham seeds and misinformation about how to use the product resulted in crop
and financial losses. this no doubt added strain to rural farmers, who had long been under
the pressures of a tight credit system that forced them to borrow from local lenders.

But, says Glover, “it is nonsense to attribute farmer suicides solely to Bt cotton”. Although
financial hardship is a driving factor in suicide among Indian farmers, there has been essen-
tially no change in the suicide rate for farmers since the introduction of Bt cotton.

that was shown by researchers at the International Food Policy research Institute in Wash-
ington Dc, who scoured government data, academic articles and media reports about Bt cot-
ton and suicide in India. their findings, published in 2008 and updated in 2011, show that
the total number of suicides per year in the Indian population rose from just under 100,000
in 1997 to more than 120,000 in 2007. But the number of suicides among farmers hovered at
around 20,000 per year over the same period.

And since its rocky beginnings, Bt cotton has benefited farmers, says Matin Qaim, an agricul-
tural economist at Georg August university in Göttingen, Germany, who has been studying
the social and financial impacts of Bt cotton in India for the past 10 years. In a study of 533
cotton-farming households in central and southern India, Qaim found that yields grew by
24% per acre between 2002 and 2008, owing to reduced losses from pest attacks. Farmers’
profits rose by an average of 50% over the same period, owing mainly to yield gains. Given the
profits, Qaim says, it is not surprising that more than 90% of the cotton now grown in India
is transgenic.

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SEctIon 3.3 The debaTe over GeneTiCally ModiFied (GM) Foods

Glenn Stone, an environmental anthro-
pologist at Washington university in St
Louis, says that the empirical evidence
for yield increases with Bt cotton is lack-
ing. He has conducted original field stud-
ies and analysed the research literature
on Bt cotton yields in India, and says
that most peer-reviewed studies report-
ing yield increases with Bt cotton have
focused on short time periods, often in
the early years after the technology came
online. this, he says, introduced biases:
farmers who adopted the technology
first tended to be wealthier and more
educated, and their farms were already
producing higher-than-average yields of
conventional cotton. they achieved high

yields of Bt cotton partly because they lavished the expensive GM seeds with care and atten-
tion. the problem now is that there are hardly any conventional cotton farms left in India to
compare GM yields and profits against, says Stone. Qaim agrees that many studies showing
financial gains focus on short-term impacts, but his study, published in 2012, controlled for
these biases and still found continued benefits.

Bt cotton did not cause suicide rates to spike, says Glover, but neither is it the sole reason for
the yield improvements. “Blanket conclusions that the technology is a success or failure lack
the right level of nuance,” he says. “It’s an evolving story in India, and we have not yet reached
a definitive conclusion.”

Transgenes Spread to Wild Crops in Mexico: Unknown
In 2000, some rural farmers in the mountains of oaxaca, Mexico, wanted to gain organic certi-
fication for the maize (corn) they grew and sold in the hope of generating extra income. David
Quist, then a microbial ecologist at the university of california, Berkeley, agreed to help in
exchange for access to their lands for a research project. But Quist’s genetic analyses uncov-
ered a surprise: the locally produced maize contained a segment of the DnA used to spur
expression of transgenes in Monsanto’s glyphosate-tolerant and insect-resistant maize.

GM crops are not approved for commercial production in Mexico. So the transgenes probably
came from GM crops imported from the united States for consumption and planted by local
farmers who probably didn’t know that the seeds were transgenic. Quist speculated at the
time that the local maize probably cross-bred with these GM varieties, thereby picking up the
transgenic DnA.

When the discovery was published in Nature, a media and political circus descended on oax-
aca. Many vilified Monsanto for contaminating maize at its historic origin—a place where
the crop was considered sacred. And Quist’s study came under fire for technical deficiencies,
including problems with the methods used to detect the transgenes and the authors’ con-
clusion that transgenes can fragment and scatter throughout the genome. Nature eventually
withdrew support for the paper but stopped short of retracting it. “the evidence available is

Consider This
consumer and health advocates are con-
cerned that GM crops with truly novel
traits, such as sunflower plants containing
fish genes, pose a risk to society and that
their approval and development is occur-
ring too rapidly. Some argue that GM crops
should be banned altogether, while others
argue for longer trial and testing periods
to ensure safety. What do you think? Are
the potential risks worth it if GM crops can
increase agricultural productivity?

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SEctIon 3.3 The debaTe over GeneTiCally ModiFied (GM) Foods

not sufficient to justify the publication of the original paper,” read an editorial footnote to a
critique of the research published in 2002.

Since then, few rigorous studies of transgene flow into Mexican maize have been published,
owing mainly to a dearth of research funding, and they show mixed results. In 2003–04, Alli-
son Snow, a plant ecologist at ohio State university in columbus, sampled 870 plants taken
from 125 fields in oaxaca and found no transgenic sequences in maize seeds.

But in 2009, a study led by Elena Alvarez-Buylla, a molecular ecologist at the national Auton-
omous university of Mexico in Mexico city, and Alma Piñeyro-nelson, a plant molecular
geneticist now at the university of california, Berkeley, found the same transgenes as Quist
in three samples taken from 23 sites in oaxaca in 2001, and in two samples taken from those
sites in 2004. In another study, Alvarez-Buylla and her co-authors found evidence of trans-
genes in a small percentage of seeds from 1,765 households across Mexico. other studies
conducted within local communities have found transgenes more consistently, but few have
been published.

Snow and Alvarez-Buylla agree that differences in sampling methods can lead to discrepan-
cies in transgene detection. “We sampled different fields,” says Snow. “they found them but
we didn’t.”

the scientific community remains split on whether transgenes have infiltrated maize popula-
tions in Mexico, even as the country grapples with whether to approve commercialization of
Bt maize.

“It seems inevitable that there will be a movement of transgenes into local maize crops,” says
Snow. “there is some proof that it is happening, but it is very difficult to say how common it is
or what are the consequences.” Alvarez-
Buylla argues that the spread of trans-
genes will harm the health of Mexican
maize and change characteristics, such
as a variety’s look and taste, that are
important to rural farmers. once the
transgenes are present, it will be very
difficult, if not impossible, to get rid of
them, she says. critics speculate that GM
traits that accumulate in the genomes of
local maize populations over time could
eventually affect plant fitness by using
up energy and resources or by disrupt-
ing metabolic processes, for example.

Snow says that there is no evidence so
far for negative effects. And she expects
that if the transgenes now in use drift
to other plants, they will have neutral
or beneficial effects on plant growth.
In 2003, Snow and her colleagues
showed that when Bt sunflowers (Heli-
anthus annuus) were bred with their wild counterparts, transgenic offspring still required
the same kind of close care as its cultivated parent but were less vulnerable to insects and

AP Photo/Natacha Pisarenko

A Spanish protest sign posted on a fence where
Monsanto is building its largest seed production
plant in Latin America in Cordoba, Argentina reads
“Stop looting and contaminating! Monsanto out of
Cordoba and Argentina.”

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SEctIon 3.3 The debaTe over GeneTiCally ModiFied (GM) Foods

produced more seeds than non-transgenic plants. Few similar studies have been conducted,
says Snow, because the companies that own the rights to the technology are generally unwill-
ing to let academic researchers perform the experiments.

In Mexico, the story goes beyond potential environmental impacts. Kevin Pixley, a crop sci-
entist and the director of the genetic resources programme at the International Maize and
Wheat Improvement centre in El Batan, Mexico, says that scientists arguing on behalf of GM
technologies in the country have missed a crucial point. “Most of the scientific community
doesn’t understand the depth of the emotional and cultural affiliation maize has for the Mexi-
can population,” he says.

tidy stories, in favour of or against GM crops, will always miss the bigger picture, which is
nuanced, equivocal and undeniably messy. transgenic crops will not solve all the agricultural
challenges facing the developing or developed world, says Qaim: “It is not a silver bullet.” But
vilification is not appropriate either. the truth is somewhere in the middle.

Adapted from Gilbert, N. (2013, May 02). Case studies: A hard look at GM crops. nature, 497, 24–26. doi:10.1038
/497024a. Retrieved from http://www.nature.com/news/case-studies-a-hard-look-at-gm-crops-1.12907.
Reprinted by permission from Macmillan Publishers Ltd. Natasha Gilbert, “Case studies: A hard look at GM crops,”
Nature 497, 24–26. Copyright © 2013.

Apply Your Knowledge
the degree to which the scientific, ethical, and political debate over GM crops has become
heated can be seen in the language used by those involved. opponents of GM crops refer
to them as “Frankenfoods” and accuse giant biotechnology firms like Monsanto of driving
farmers to suicide in their pursuit of profit. Proponents of GM crops accuse opponents of
being anti-science extremists who are responsible for the starvation and death of children
in poor countries. As the previous article concluded, however, the truth is likely somewhere
in the middle.

In order to test your own knowledge and opinion on GM crops it’s important to first start with
some background material. the links below will help you better understand some of the basic
issues surrounding GM crops, such as

• health risks associated with GM crops including the development of new allergens and
toxins in foods;

• ecological risks and unintended side effects, including the spread of herbicide-resistant
weeds, the transfer of genes from GM crops to non-GM crops, and unexpected impacts
on wildlife.

these readings, like the debate itself, tend to come down more on one side or the other, but
they are relatively balanced and help introduce the major issues. review them to enhance your
knowledge of this subject.

• http://www.fas.org/biosecurity/education/dualuse-agriculture/2.-agricultural
-biotechnology/genetically-engineered-crops.html

• http://www.who.int/foodsafety/publications/biotech/en/20questions_en

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http://www.nature.com/news/case-studies-a-hard-look-at-gm-crops-1.12907

http://www.fas.org/biosecurity/education/dualuse-agriculture/2.-agricultural-biotechnology/genetically-engineered-crops.html

http://www.who.int/foodsafety/publications/biotech/en/20questions_en

SEctIon 3.4 GLoBAL FISHErIES

3.4 Global Fisheries
Seafood provides for roughly 15 percent of all animal protein consumed globally by humans,
and this percentage is much higher in some developing countries. Therefore, managing global
fisheries is equally as important as the way agriculture is sustained. In this article, Paul Green-
berg of national Geographic Magazine reviews trends in the global fish catch and introduces the
concept of the “seafood print” as a means of measuring the environmental impact of different
kinds of fish consumption.

Rather than look at just the volume of seafood harvested from a fishery, the seafood print
approach focuses on the type of fish caught. Fish that are at or near the top of the food chain,
and with essentially no predators of their own (such as Bluefin tuna), are known as apex or top
predators. Apex fish consume large amounts of smaller fish in order to survive and grow, and in
turn these smaller fish eat even larger amounts of fish that are lower on the food chain—this is
the same concept as trophic levels introduced in section 1.2. As a result, harvesting and eating
one ton of Bluefin tuna actually has a much larger seafood print than eating many more tons
of fish overall. This same concept of eating higher on the food chain applies to meat as well. In
order to produce one ton of meat, we need many more tons of grain. This is one of the reasons
for the concern over grain supplies reviewed in section 3.1.

To deal with these interrelated issues in food production, scientists focus on the concept of pri-
mary production (also reviewed in section 1.2) to develop a measure such as the seafood print.
In the ocean, most primary production is accomplished by algae known as phytoplankton, and
these serve as the base of the oceanic food web. Phytoplankton are eaten by small floating animals

Apply Your Knowledge

(continued)

• http://www.ucsusa.org/food_and_agriculture/our-failing-food-system/genetic

-engineering/risks-of-genetic-engineering.html
• http://www.fda.gov/Food/FoodScienceresearch/Biotechnology/ucm346030.htm
• http://www.isaaa.org/resources/publications/pocketk/1/

once you have reviewed this material, visit this site, which will allow you to vote on whether
we should grow GM crops or not (http://www.pbs.org/wgbh/harvest/exist/). Start by read-
ing the Introduction and then answering the yes/no question at the bottom of the page. Based
on your first and subsequent answers you will repeatedly be challenged in your beliefs. Work
through all of the questions. on the final page you’ll have a chance to review all 12 arguments
for and against GM crops (six in favor and six opposed). Have a look at these and then ask
yourself the following questions:

• What side did you tend to favor in the debate? How strong was your support for that side?
• What arguments did you find most compelling in forming your own opinion? Why did

you find these so important?
• Given the uncertainty and complexity involved in the debate over GM crops, how should

we, as a society, regulate their development and use?
• What was the most important lesson you learned from this exercise?

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http://www.ucsusa.org/food_and_agriculture/our-failing-food-system/genetic-engineering/risks-of-genetic-engineering.html

http://www.fda.gov/Food/FoodScienceResearch/Biotechnology/ucm346030.htm

http://www.isaaa.org/resources/publications/pocketk/1/

http://www.pbs.org/wgbh/harvest/exist/

SEctIon 3.4 GLoBAL FISHErIES

known as zooplankton, which, in turn,
are eaten by small fish such as sardines
and menhaden. These small fish then
become the food source for larger fish
and apex predators like the bluefin
tuna. In the same way, the impacts of
moving fish production to fish farms, or
aquaculture, will depend on the type
of fish being raised. For example, farm-
raised salmon are fed large amounts
of fish meal from wild-caught stocks of
small fish and so they have a significant
seafood print, Whereas farm-raised
tilapia eat mainly plant material and
so have a smaller seafood print. These
and other issues surrounding global
fisheries are discussed below.

By Paul Greenberg
Every year more than 170 billion pounds (77.9 million metric tons) of wild fish and shellfish
are caught in the oceans—roughly three times the weight of every man, woman, and child in
the united States. Fisheries managers call this overwhelming quantity of mass-hunted wild-
life the world catch, and many maintain that this harvest has been relatively stable over the
past decade. But an ongoing study conducted by Daniel Pauly, a fisheries scientist at the uni-
versity of British columbia, in conjunction with Enric Sala, a national Geographic fellow, sug-
gests that the world catch is neither stable nor fairly divided among the nations of the world.
In the study, called SeafoodPrint and supported by the Pew charitable trusts and national
Geographic, the researchers point the way to what they believe must be done to save the seas.

they hope the study will start by correcting a common misperception. the public imagines
a nation’s impact on the sea in terms of the raw tonnage of fish it catches. But that turns out
to give a skewed picture of its real impact, or seafood print, on marine life. “the problem is,
every fish is different,” says Pauly. “A pound of tuna represents roughly a hundred times the
footprint of a pound of sardines.”

the reason for this discrepancy is that tuna are apex predators, meaning that they feed
at the very top of the food chain. the largest tuna eat enormous amounts of fish, including
intermediate-level predators like mackerel, which in turn feed on fish like anchovies, which
prey on microscopic copepods [small crustaceans]. A large tuna must eat the equivalent of
its body weight every ten days to stay alive, so a single thousand-pound tuna might need to
eat as many as 15,000 smaller fish in a year. Such food chains are present throughout the
world’s ocean ecosystems, each with its own apex animal. Any large fish—a Pacific swordfish,
an Atlantic mako shark, an Alaska king salmon, a chilean sea bass—is likely to depend on
several levels of a food chain.

. Vik Thomas/iStock/Thinkstock

the impact of aquaculture depends on the fish stocks
raised on the farm. Salmon and tuna farms have a higher
seafood print than do farms producing smaller fish.

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SEctIon 3.4 GLoBAL FISHErIES

The SeafoodPrint
to gain an accurate picture of how different nations have been using the resources of the sea,
the SeafoodPrint researchers needed a way to compare all types of fish caught. they decided
to do this by measuring the amount of “primary production”—those microscopic organisms
at the bottom of the marine food web—required to make a pound of a given type of fish. they
found that a pound of bluefin tuna, for example, might require a thousand pounds or more of
primary production.

In assessing the true impact that nations have on the seas, the team needed to look not just
at what a given nation caught but also at what the citizens of that nation ate. “A country can
acquire primary production by fishing, or it can acquire it by trade,” Pauly says. “It is the sheer
power of wealthy nations to acquire primary production that is important.”

nations with money tend to buy a lot of fish, and a lot of the fish they buy are large apex preda-
tors like tuna. Japan catches less than five million metric tons of fish a year, a 29 percent drop
from 1996 to 2006. But Japan consumes nine million metric tons a year, about 582 million
metric tons in primary-production terms. though the average chinese consumer generally
eats smaller fish than the average Japanese consumer does, china’s massive population gives
it the world’s biggest seafood print, 694 million metric tons of primary production. the u.S.,
with both a large population and a tendency to eat apex fish, comes in third: 348.5 million
metric tons of primary production. And the size of each of these nations’ seafood prints is
growing. What the study points to, Pauly argues, is that these quantities are not just extremely
large but also fundamentally unsustainable.

Overfishing
Exactly how unsustainable can be seen in global analyses of seafood trade compiled by Wilf
Swartz, an economist working on SeafoodPrint. Humanity’s consumption of the ocean’s pri-
mary production changed dramatically from the 1950s to the early 2000s. In the 1950s much
less of the ocean was being fished to meet our needs. But as affluent nations increasingly
demanded apex predators, they exceeded the primary-production capacities of their exclu-
sive economic zones, which extend up to 200 nautical miles from their coasts. As a result,
more and more of the world’s oceans had to be fished to keep supplies constant or growing.

Areas outside of these zones are known in nautical parlance as the high seas. these vast ter-
ritories, the last global commons on Earth, are technically owned by nobody and everybody.
the catch from high-seas areas has risen to nearly ten times what it was in 1950, from 1.6
million metric tons to around 13 million metric tons. A large part of that catch is high-level,
high-value tuna, with its huge seafood print.

the wealthier nations that purchase most of the products of these fisheries are essentially
privatizing them. Poorer countries simply cannot afford to bid for high-value species. citizens
in these nations can also lose out if their governments enter into fishing or trade agreements
with wealthier nations. In these agreements local fish are sold abroad and denied to local
citizens—those who arguably have the greatest need to eat them and the greatest right to
claim them.

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SEctIon 3.4 GLoBAL FISHErIES

Although supermarkets in developed nations like the u.S. and Japan still abound with fish
flesh, SeafoodPrint suggests that this abundance is largely illusory because it depends on
these two troubling phenomena: broader and broader swaths of the high seas transformed
from fallow commons into heavily exploited, monopolized fishing grounds; and poor nations’
seafood wealth spirited away by the highest bidder.

Humanity’s demand for seafood has now
driven fishing fleets into every virgin fish-
ing ground in the world. there are no new
grounds left to exploit. But even this isn’t
enough. An unprecedented buildup of fish-
ing capacity threatens to outstrip seafood
supplies in all fishing grounds, old and
new. A report by the World Bank and the
Food and Agriculture organization (FAo)
of the united nations recently concluded
that the ocean doesn’t have nearly enough
fish left to support the current onslaught.
Indeed, the report suggests that even if we
had half as many boats, hooks, and nets as
we do now, we would still end up catching
too many fish.

Some scientists, looking at the same data, see a different picture than Daniel Pauly does. ray
Hilborn, a fisheries scientist at the university of Washington, doesn’t think the situation is so
dire. “Daniel is fond of showing a graph that suggests that 60 to 70 percent of the world’s fish
stocks are overexploited or collapsed,” he says. “the FAo’s analysis and independent work I
have done suggests that the number is more like 30 percent.” Increased pressure on seafood
shouldn’t come as a surprise, he adds, since the goal of the global fishing industry is to fully
exploit fish populations, though without damaging their long-term viability.

The SeafoodPrint in Action
Many nations, meanwhile, are trying to compensate for the world’s growing seafood deficit
by farming or ranching high-level predators such as salmon and tuna, which helps maintain
the illusion of abundance in the marketplace. But there’s a big problem with that approach:
nearly all farmed fish consume meal and oil derived from smaller fish. this is another way
that SeafoodPrint might prove useful. If researchers can tabulate the ecological value of wild
fish consumed on fish farms, they could eventually show the true impact of aquaculture
[fish farming].

Given such tools, policymakers might be in a better position to establish who is taking what
from the sea and whether that is just and sustainable. As a global study, SeafoodPrint makes
clear that rich nations have grossly underestimated their impacts. If that doesn’t change, the
abundance of fish in our markets could drop off quickly. Most likely the wealthy could still
enjoy salmon and tuna and swordfish. But middle-class fish-eaters might find their seafood
options considerably diminished, if not eliminated altogether.

Consider This
Both Daniel Pauly and ray Hilborn are
respected fisheries scientists. Yet one of
them estimates that 60–70 percent of
the world’s fish stocks are overexploited,
while the other suggests this number is
closer to 30 percent. Why might two scien-
tists come to such different conclusions?
What is it about understanding wild fish-
eries, in particular, that makes developing
such an estimate difficult?

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SEctIon 3.4 GLoBAL FISHErIES

What then is SeafoodPrint’s long-range potential? could some version of it guide a conserva-
tion agreement in which nations are given a global allowance of oceanic primary production
and fined or forced to mend their ways if they exceed it?

“that would be nice, wouldn’t it?” Pauly says. He points out that we already know several
ways to shrink our impact on the seas: reduce the world’s fishing fleets by 50 percent, estab-
lish large no-catch zones, limit the use of wild fish as feed in fish-farming. unfortunately, the
seafood industry has often blocked the road to reform.

SeafoodPrint could also give consumers a map around that roadblock—a way to plot the
course toward healthy, abundant oceans. today there are dozens of sustainable-seafood cam-
paigns, each of which offers suggestions for eating lower on the marine food chain. these
include buying farmed tilapia instead of farmed salmon, because tilapia are largely herbiv-
orous and eat less fish meal when farmed; choosing trap-caught black cod over long-lined
chilean sea bass, because fewer unwanted fish are killed in the process of the harvest; and
avoiding eating giant predators like Atlantic bluefin tuna altogether, because their numbers
are simply too low to allow any harvest at all.

Protecting the Seas
the problem, say conservationists, is that the oceans have reached a critical point. Simply
changing our diets is no longer sufficient if fish are to recover and multiply in the years
ahead. What Pauly and other conservation biologists now believe is that suggestions must be
transformed into obligations. If treaties can establish seafood-consumption targets for every
nation, they argue, citizens could hold their governments responsible for meeting those tar-
gets. comparable strategies have worked to great effect in terrestrial ecosystems, for trade
items such as furs or ivory. the ocean deserves a similar effort, they say.

“Barely one percent of the ocean is now protected, compared with 12 percent of the land,”
Enric Sala adds, “and only a fraction of that is fully protected.” that’s why national Geographic
is partnering with governments, businesses, conservation organizations, and citizens to pro-
mote marine reserves and help reduce the impact of fishing around the globe.

In the end, neither Pauly nor Sala nor the rest of the SeafoodPrint team wants to destroy the
fishing industry, eliminate aquaculture, or ban fish eating. What they do want to change is
business as usual. they want to let people know that today’s fishing and fish-farming prac-
tices are not sustainable and that the people who advocate maintaining the status quo are
failing to consider the ecological and economic ramifications. By accurately measuring the
impacts nations have on the sea, SeafoodPrint may lay the groundwork for effective change,
making possible the rebuilding of the ocean’s dwindling wealth. Such a course, Pauly believes,
could give the nations of the world the capability, in the not too distant future, to equita-
bly share a truly bountiful, resurrected ocean, rather than greedily fight over the scraps that
remain in the wake of a collapse.

Adapted from Greenberg, P. (2010). Time for a Sea Change. national Geographic Magazine. Retrieved from http://
ngm.nationalgeographic.com/print/2010/10/seafood-crisis/greenberg-text. Paul Greenberg/National Geo-
graphic Creative. Used by permission.

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http://ngm.nationalgeographic.com/print/2010/10/seafood-crisis/greenberg-text

SEctIon 3.5 Case hisTory—The rise oF The loCal Foods MoveMenT

3.5 Case History—The Rise of the Local Foods Movement
Our modern food system not only provides us with an abundance of food at relatively low prices,
it also allows us to eat different foods at almost any time of the year, even if they are out of
season. Earlier generations of Americans expected to have fresh strawberries only in June or
July and fresh apples in September and October. Today, however, fresh strawberries and apples,
as well as raspberries, grapes, peaches, beans, and mangoes, are available in supermarkets
throughout the year.

This trend, combined with increased consumption of processed foods and the concentration of
meat production has given rise to a concept known as “food miles.” Food miles are a measure
of how far our food travels on average from where it is produced to where it is consumed. Since
transport of food requires the use of fossil fuels, an increase in food miles is likely to increase the
overall environmental impact of that product. Recent studies have found that most supermarket
produce has traveled an average of 1,500 miles, and one study estimated that it requires 435
calories of fossil fuel energy to transport a 5-calorie strawberry from California to New York
(Cohen, 2008).

Awareness of the environmental impacts of food miles combined with growing concern over food
safety have led more and more Americans to grow their own food or seek out local producers. In
this article, Lester Brown of the Worldwatch Institute summarizes these trends and argues that
they could be the early signs of a more fundamental shift in the way food is grown, marketed,
and consumed in this country. Brown argues that a shift to purchasing more local foods can sig-
nificantly decrease food miles and reduce other environmental impacts of conventional agricul-
ture. For example, more localized livestock production can address some of the problems caused
by concentrated animal feeding operations (CAFOs) and encourage a return to integrated crop-
livestock operations that characterized almost all agricultural systems until very recently.

By L. Brown
In the united States, there has been a
surge of interest in eating fresh local
foods, corresponding with mounting
concerns about the climate effects of
consuming food from distant places
and about the obesity and other health
problems associated with junk food
diets. this is reflected in the rise in
urban gardening, school gardening,
and farmers’ markets.

With the fast-growing local foods move-
ment, diets are becoming more locally
shaped and more seasonal. In a typical
supermarket in an industrial country
today it is often difficult to tell what sea-
son it is because the store tries to make
everything available on a year-round

. Vasiliki Varvaki/iStock/Thinkstock

Many people find locally grown food to be fresher
than foods shipped thousands of miles, and enjoy
purchasing directly from farmers.

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SEctIon 3.5 Case hisTory—The rise oF The loCal Foods MoveMenT

basis. As oil prices rise, this will become less common. In essence, a reduction in the use of oil
to transport food over long distances—whether by plane, truck, or ship—will also localize the
food economy.

this trend toward localization is reflected in the recent rise in the number of farms in the
united States, which may be the reversal of a century-long trend of farm consolidation.
Between the agricultural census of 2002 and that of 2007, the number of farms in the united
States increased by 4 percent to roughly 2.2 million. the new farms were mostly small, many
of them operated by women, whose numbers in farming jumped from 238,000 in 2002 to
306,000 in 2007, a rise of nearly 30 percent.

Many of the new farms cater to local markets. Some produce fresh fruits and vegetables
exclusively for farmers’ markets or for their own roadside stands. others produce special-
ized products, such as the goat farms that produce milk, cheese, and meat or the farms
that grow flowers or wood for fireplaces. others specialize in organic food. the number of
organic farms in the united States jumped from 12,000 in 2002 to 18,200 in 2007, increas-
ing by half in five years.

Gardening
Gardening was given a big boost in the spring of 2009 when u.S. First Lady Michelle obama
worked with children from a local school to dig up a piece of lawn by the White House to start
a vegetable garden. there was a precedent. Eleanor roosevelt planted a White House victory
garden during World War II. Her initiative encouraged millions of victory gardens that even-
tually grew 40 percent of the nation’s fresh produce.

Although it was much easier to expand home gardening during World War II, when the united
States was largely a rural society, there is still a huge gardening potential—given that the
grass lawns surrounding u.S. residences collectively cover some 18 million acres. converting
even a small share of this to fresh vegetables and fruit trees could make an important contri-
bution to improving nutrition.

Many cities and small towns in the united States and England are creating community gar-
dens that can be used by those who would otherwise not have access to land for gardening.
Providing space for community gardens is seen by many local governments as an essential
service, like providing playgrounds for children or tennis courts and other sport facilities.

Local Markets
Many market outlets are opening up for local produce. Perhaps the best known of these are
the farmers’ markets where local farmers bring their produce for sale. In the united States,
the number of these markets increased from 1,755 in 1994 to more than 4,700 in mid-2009,
nearly tripling over 15 years. Farmers’ markets reestablish personal ties between produc-
ers and consumers that do not exist in the impersonal confines of the supermarket. Many
farmers’ markets also now take food stamps, giving low-income consumers access to fresh
produce that they might not otherwise be able to afford. With so many trends now boosting
interest in these markets, their numbers may grow even faster in the future.

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SEctIon 3.5 Case hisTory—The rise oF The loCal Foods MoveMenT

Schools
In school gardens, children learn how food is produced, a skill often lacking in urban settings,
and they may get their first taste of freshly picked peas or vine-ripened tomatoes. School gar-
dens also provide fresh produce for school lunches. california, a leader in this area, has 6,000
school gardens.

Many schools and universities are now
making a point of buying local food because
it is fresher, tastier, and more nutritious,
and it fits into new campus greening pro-
grams. Some universities compost kitchen
and cafeteria food waste and make the
compost available to the farmers who sup-
ply them with fresh produce.

Supermarkets are increasingly contract-
ing with local farmers during the season
when locally grown produce is available.
upscale restaurants emphasize locally

grown food on their menus. In some cases, year-round food markets are evolving that mar-
ket just locally produced foods, including not only fruit and vegetables but also meat, milk,
cheese, eggs, and other farm products.

The Benefits of Local
Food from more distant locations boosts carbon emissions while losing flavor and nutri-
tion. A survey of food consumed in Iowa showed conventional produce traveled on average
1,500 miles, not including food imported from other countries. In contrast, locally grown
produce traveled on average 56 miles—a huge difference in fuel investment. And a study in
ontario, canada, found that 58 imported foods traveled an average of 2,800 miles. Simply put,
consumers are worried about food security in a long-distance food economy. this trend has
led to a new term: locavore, complementing the better known terms herbivore, carnivore,
and omnivore. [. . .]

As agriculture localizes, livestock production will likely start to shift away from mega-sized
cattle, hog, and poultry feeding operations. the shift from factory farm production of milk,
meat, and eggs by returning to mixed crop-livestock operations facilitates nutrient recycling
as local farmers return livestock manure to the land. the combination of high prices of natu-
ral gas, which is used to make nitrogen fertilizer, and of phosphate, as reserves are depleted,
suggests a much greater future emphasis on nutrient recycling—an area where small farmers
producing for local markets have a distinct advantage over massive feeding operations.

In combination with moving down the food chain to eat fewer livestock products, reducing
the food miles in our diets can dramatically reduce energy use in the food economy. And as
world food insecurity mounts, more and more people will be looking to produce some of their
own food in backyards, in front yards, on rooftops, in community gardens, and elsewhere,
further contributing to the localization of agriculture.

Adapted from Chapter 9, “Feeding Eight Billion People Well,” in Lester R. Brown, Plan B 4.0: Mobilizing to Save
civilization. Copyright © Earth Institute 2009. Retrieved from http://www.earth-policy.org/index.php?/book
_bytes/2009/pb4ch09_ss5#”. Used by permission.

Consider This
Besides providing students with fresh pro-
duce, school gardens are also being touted as
an important environmental education tool.
What lessons and concepts from environ-
mental science can students gain through
the act of gardening?

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Summary & Resources

chapter Summary
In the last chapter, we learned that even though fertility rates are declining and population
growth is slowing, global population is expected to reach over nine billion later this century.
More people, combined with more widespread affluence and rising meat consumption, means
we will have to continue to increase food production in order to feed the world. How that food
is grown, processed, and distributed can have significant impacts on the environment, and
there is concern that conventional approaches cannot be sustained over the long term.

one approach to increasing food production that began roughly 50 years ago was the first
green revolution. this movement achieved remarkable success in raising global grain pro-
duction at a time when world population was growing rapidly. Green revolution agriculture
focused on monocultures of single crops and required significant inputs of energy, water,

Apply Your Knowledge
Whether it’s water, energy, or food, we seldom stop to think where these critical items come
from and how they get to us at the very moment we need them. How often do we stop and ask
where our food comes from, how it’s grown, processed, and shipped to where we buy it? And
yet our food consumption habits can have enormous impacts on the environment and our
personal health. For this exercise complete the following steps:

Step 1—Sit down and list the kinds of foods you usually eat and how much of them you
eat over the course of a typical week. It might help to break these down into fruits, veg-
etables, meats (including seafood), dairy products, etc. List the top ten foods that you eat
and try to estimate the quantity of your consumption over the course of the week. For
example, this could be as simple as saying “five apples a week,” or as complicated as “five
hamburgers a week, each weighing 1/3 pound, equaling 1.66 pounds of beef per week.”
List these ten types of foods along with estimated consumption.

Step 2—Pick three of these top ten foods and determine where they typically come from.
You’ll need to do a little sleuthing at the supermarket or on the Internet, but you should
be able to determine where your favorite foods typically are produced. For example, you
can visit a supermarket and look at boxes or signs to determine where most of the fruits
and vegetables on display originate. A search on the Internet can tell you a lot about
where most of the beef, pork, or chicken is produced in the united States.

Step 3—using knowledge you’ve gained from this chapter as well as some of the resources
provided at the end of this chapter, list some of the significant environmental and health
impacts associated with the growing, processing and distribution of these foods.

Step 4—use the Food carbon Emissions calculator found here (http://www.food
emissions.com/foodemissions/calculator.aspx) to examine some of the impacts of your
food consumption. Vary the food category, commodity, and assumptions about miles
traveled and percentage wasted to see how this changes your results. How comprehen-
sive is this calculator in terms of measuring the overall impact of your food consumption
choices? What factors might it not be measuring?

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fertilizers, pesticides, and herbicides. As with many issues in the study of the environment,
we are confronted here with tradeoffs. the high-input approach to agriculture has increased
food production dramatically, almost certainly averting famine in some regions and provid-
ing an abundance of relatively cheap food in countries like the united States. However, this
approach has also resulted in a number of environmental challenges, including the following:

• Heavy pumping of groundwater for irrigation has lowered water tables and resulted
in salinization—the buildup of mineral salts in the soil—in many regions.

• Mechanization and continuous plowing has worsened soil erosion and the loss of top-
soil, necessitating heavier use of synthetic fertilizers to make up for lost soil fertility.

• Fertilizer runoff from farms enters water bodies and can result in algal blooms,
known as eutrophication. When the algae decompose, oxygen levels in the water are
depleted, and this can result in the death of aquatic and marine life.

• Monocultures create ideal conditions for insect pests and weeds, necessitating heavy
applications of chemical pesticides and herbicides to reduce crop losses.

• conventional agriculture is highly energy-intensive. Much of this energy is consumed
in the production of synthetic fertilizers and pesticides, as well as in the processing
and shipment of foods over long distances.

• Large-scale meat production from concentrated animal feeding operations has
resulted in waste management problems and necessitated the greater use of antibi-
otics to control the spread of disease—a situation that some experts worry is leading
to the development of strains of antibiotic-resistant bacteria.

one solution being touted as a means of meeting this challenge is genetic engineering and
the genetic modification of crops. this approach aims to develop specific traits in crops that
would maintain productivity while reducing the need for inputs of water, fertilizer, and pesti-
cides. Another approach, known as agroecology or sustainable agriculture, focuses on manag-
ing a farm as an ecological system, paying attention to nutrient cycles, monitoring the inter-
actions between plants and other organisms, and balancing resource use with availability.
While these two approaches—genetic engineering and agroecology—need not be mutually
exclusive, they are usually presented and discussed as if they were. ultimately, in order to
continue feeding the world in the decades ahead, it may be that every possible option has to
remain on the table.

Indeed, meeting the food demands of a growing population in a way that does not undermine
the environment is one of the great challenges of our time. As we’ll see in the next chapter,
growing food demands are already driving the conversion of tropical rainforests to farmland
and the use of synthetic fertilizers at a rate that is actually beginning to change the global
nitrogen and phosphorous cycles.

Working Toward Solutions
the readings in this chapter might leave you feeling overwhelmed and pessimistic about the
prospects for feeding the world in a sustainable fashion. However, there are thousands of
examples from around the world of farmers, ranchers, fishers, and scientists working together
to reduce the environmental impact of food production and meet the needs of a growing popu-
lation. the discussion below highlights some of the approaches being used to improve

(continued)

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Working Toward Solutions (continued)
agricultural sustainability and the science, economics, and policy behind them. It also pro-
vides some hints for what individuals can do to reduce the environmental impact of their own
food consumption choices.

there are a whole range of approaches and practices that fall under the umbrella term of sus-
tainable agriculture. the u.S. Department of Agriculture (uSDA) published a comprehensive
survey of these in a 1999 report found here (http://www.nal.usda.gov/afsic/pubs/terms
/srb9902.shtml). the report starts with a definition of what we mean by sustainable, some-
thing we want to maintain or keep in existence over a long period of time. clearly, an approach
to agriculture that depletes and pollutes water supplies, destroys soil resources, relies heavily
on nonrenewable energy supplies, and poisons people and animals with pesticides and agri-
cultural chemicals is not sustainable.

Sustainable alternatives, therefore, have to preserve water supplies and protect water quality,
maintain soil health and productivity, rely primarily on renewable energy inputs and solar
energy, and limit or eliminate the use of pesticides and other potentially hazardous agricultural
chemicals. one approach to doing this is known as agroecology. Agroecology is an attempt to
design and develop agricultural systems that mimic or copy natural, ecological systems. For
example, consider that natural forest or grassland systems can be incredibly productive over
long periods of time while generating positive environmental benefits (such as clean air and
water) known as ecosystem services. these systems do not rely on external inputs of energy,
water, or fertilizers or other chemicals to maintain their productivity. Agroecology seeks to do
the same thing for agriculture.

Specific practices that are used in agroecology and sustainable agriculture might include the
following:

• crop rotation—rather than plant the same crop year after year, farmers rotate crops
over time. this approach disrupts pest reproduction cycles, reducing the need for pes-
ticides, and can also reduce the need for fertilizer since different plants often require
different nutrients.

• no-till and low-till farming—Growing crops without tilling or disturbing the soil
reduces soil erosion and runoff.

• Soil-building crops—Some plants, such as clover and legumes, are capable of absorbing
nitrogen from the atmosphere and depositing it in the soil, enhancing soil quality. these
plants can be inter-cropped or planted alongside other crops to maintain soil fertility.

• Integrated pest management (IPM)—crop rotation, inter-cropping, and increased crop
diversity generally lead to fewer pest problems than monocultures. IPM also seeks to
maintain balance in a field between destructive pests and beneficial insects (such as
ladybugs and praying mantises) that feed on them.

• organic agriculture—Minimizing or eliminating the use of synthetic fertilizers, pesticides,
and herbicides through careful management of soil fertility and insect populations.

Despite the apparent benefits of these approaches there are political, economic, and other bar-
riers to more widespread adoption of sustainable agricultural practices. For starters, govern-
ment subsidies to agriculture in countries like the united States are often based on the amount

(continued)

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Post-test

1. the poorest people on the planet spend from _______ to ________ percent of their
income on food.

a. 10 to 20
b. 20 to 30
c. 30 to 50
d. 50 to 70

2. Which of the following is not an attribute that has an important impact on soil
quality?

a. texture
b. Depth
c. color
d. Permeability

3. A situation in which weeds evolve so that chemical sprays are no longer effective in
controlling them is known as

a. pesticide resistance.
b. herbicide resistance.
c. nutrient management.
d. chemical resistance.

Working Toward Solutions (continued)
of acreage devoted to a specific crop. this encourages monocultures and discourages crop
rotation and inter-cropping since these would reduce the size of the subsidy payment. Second,
sustainable practices require a fair amount of knowledge, careful monitoring, and experimen-
tation. Many farmers, already operating with heavy debt burdens, are reluctant to change the
way they farm for fear of lower yields and profitability. Lastly, the societal costs of conven-
tional agricultural practices—such as air and water pollution—are typically not reflected in
the prices we pay for our food. this makes organic agriculture and food produced in a more
sustainable fashion appear more expensive than it actually is.

As individuals we can support a move toward more sustainable agriculture by paying more
attention to where our food comes from and how it is produced. Where possible, and when
affordable, organic products are likely to have less environmental impact than non-organic.
Supporting local farmers is another way to reduce the environmental impact of our food con-
sumption. one way to do this is by joining a community-supported agriculture (cSA) group in
your area. A cSA consists of a group of consumers who pay a local farmer a fixed price (or sub-
scription) for a share of that farmer’s produce over the course of the year. You can learn more
about sustainable agriculture and see if there are any cSAs in your area by going to these sites:

• http://www.nal.usda.gov/afsic/pubs/csa/csa.shtml
• http://newfarm.rodaleinstitute.org/embedfarmlocator/
• http://www.localharvest.org/csa/

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http://newfarm.rodaleinstitute.org/embedfarmlocator/

http://www.localharvest.org/csa/

SuMMArY & rESourcES

4. A measure developed by marine biologists to estimate the amount of primary pro-
duction required to make a pound of different kinds of fish is known as

a. the ecological footprint.
b. the seafood print.
c. the marine food web.
d. sustainable production.
5. Which of the following is a method that promotes nutrient recycling?
a. Having mega-sized livestock
b. Having a chicken farm
c. Having a mixed crop-livestock operation
d. Having a corn and grain farm

6. rising demand for pork in china has led to the rapid expansion of soybean produc-
tion and deforestation in

a. the united States.
b. canada.
c. Brazil.
d. South Africa.

7. the major source of nitrogen and phosphorous pollution in the Gulf of Mexico is
a. suburban sprawl.
b. oil refineries.
c. agriculture.
d. mining.

8. the controversy over genetically modified (GM) crops has been especially serious in
which of the following countries, where GM maize (corn) is believed to have mixed
with traditional varieties?

a. Germany
b. russia
c. china
d. Mexico

9. Which of the following is the BESt way to lower your individual seafood print?
a. Eat farmed tilapia
b. Eat farmed salmon
c. Eat Bluefin tuna
d. Eat chilean sea bass.

10. Which of these is the BESt explanation for the 4 percent growth in the number of
farms in the u.S. between 2002 and 2007?

a. Growth in large farms producing soybeans for export to china
b. Growth in small farms producing for local markets
c. Growth in small farms producing for export
d. Growth in large farms producing apples for export to France

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Answers
1. d. 50 to 70. the answer can be found in section 3.1.
2. c. color. the answer can be found in section 3.2.
3. b. herbicide resistance. the answer can be found in section 3.3.
4. b. the seafood print. the answer can be found in section 3.4.
5. c. Having a mixed crop-livestock operation. the answer can be found in section 3.5.
6. c. Brazil. the answer can be found in section 3.1.
7. c. agriculture. the answer can be found in section 3.2.
8. d. Mexico. the answer can be found in section 3.3.
9. a. Eat farmed tilapia. the answer can be found in section 3.4.
10. b. Growth in small farms producing for local markets. the answer can be found in section 3.5.

Key Ideas

• For the past 50 years, green revolution approaches to agriculture—combining new
crop varieties with expanded irrigation, fertilizers, and pesticides to control pests
and weeds—have greatly increased crop yields and helped avert famine in many
regions of the world. However, agricultural productivity has begun to stagnate while
rising populations, changing diets, and increased demand for biofuels from crops is
putting increased pressure on global food supplies.

• Higher levels of meat consumption require even greater increases in grain produc-
tion since it takes many more calories of grain fed to an animal to produce a single
calorie of meat. A shift to more of a meat-based diet therefore increases the land
area devoted to agriculture as well as the consumption of water, energy, and agricul-
tural chemicals.

• close to half of America’s land area is dedicated to growing crops or pasture for
animals. Agricultural activities on these lands can degrade soil quality, water quality,
and air quality.

• Agriculture is the leading cause of impairment or pollution of America’s rivers and
lakes. this includes sediment from soil erosion, runoff of nitrogen and phospho-
rous fertilizers, and runoff of pesticides and herbicides. nitrogen and phosphorous
runoff leads to algae blooms, eutrophication, and hypoxia, or low oxygen levels in
water bodies.

• Agriculture is also an important contributor to air pollution in the form of nitrous
oxides, methane, carbon dioxide, and particulates or dust.

• unlike traditional plant breeding, which combines traits from the same plant types
to produce better varieties, genetic engineering or biotechnology involves moving
genetic material from one organism to another, perhaps completely different, organ-
ism. the goal of genetic engineering is to select genes that possess desirable traits,
such as resistance to drought or insects, and insert them into another organism that
does not already benefit from the desirable trait.

• Globally, over 170 billion pounds of wild fish and shell fish are caught in the oceans
each year, and seafood accounts for roughly 15 percent of all animal protein con-
sumed by humans. By some estimates, 60 to 70 percent of the world’s wild fish
stocks are overexploited or already collapsed.

• Apex predator fish species such as Bluefin tuna and Pacific swordfish feed at the
very top of the food chain, eating as many as 15,000 smaller fish a year to survive.
For this reason, human consumption of apex predator fish species has a larger
impact, or seafood print, on global fisheries than does eating an equivalent amount
of fish lower down the food chain.

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• the concept of food miles can be used to measure how far our food travels from
where it is produced to where it is consumed. Higher food miles generally mean a
greater environmental impact since more fossil fuels are used in transportation. A
local foods movement focused on farmers’ markets and gardening in homes and
schools is growing rapidly in response to an awareness of food miles.

critical thinking and Discussion Questions

1. the two commodities of food and energy are both critical in our day-to-day lives.
We couldn’t survive without food, and it’s hard to imagine how we’d get by without
energy to move our cars, light and heat our homes, and power our economy. It turns
out that these two commodities are also very tightly linked. think about a recent
meal you consumed and then try to account for all of the ways in which energy was
used to get that meal in front of you, going as far back in the production process as
possible. What does this say about the environmental impact of agriculture and the
security of our food system in an age of unstable energy supplies?

2. Experts disagree over whether continued increases in population will lead to
more widespread famine in the future. Some argue that we have already exploited
the best lands for agriculture and that green revolution approaches are no lon-
ger increasing yields. others suggest that new approaches to agriculture, such as
genetic engineering, will increase production enough to avert disaster. Still oth-
ers argue that there is more than enough food in the world if people are willing to
adjust their diets and, for example, eat less meat. How compelling do you find each
of these arguments? What does it suggest to you about what needs to be done to
meet our food needs in the future?

3. Agriculture is a persistent and leading cause of water pollution in the united States.
In contrast, since the 1960s there has been great progress made in reducing water
pollution from large industrial and sewage treatment facilities. What is it about an
activity like agriculture that might make it more difficult to control runoff and pollu-
tion compared to large industrial facilities?

4. Whether you realize it or not, genetically modified corn, soybeans, and other crops
are already present in much of the food you eat. At least in the united States, con-
cerns over consumer safety from genetic engineering have not slowed the devel-
opment of these products. What kinds of safety research and testing do you think
should occur before genetically engineered crops are approved for mass production
and human consumption? How might the basic principles of the scientific method be
used to design and carry out that research?

5. How is genetic modification different from traditional cross-breeding techniques?
What are the ramifications of these differences? consider both intentional results
and unintended consequences.

6. Aquaculture, or fish farming, is frequently touted as a more sustainable alterna-
tive to seafood production than catching wild fish. Yet not all forms of aquaculture
are as sustainable as others. As section 3.4 points out, eating farmed tilapia is more
sustainable than eating farmed salmon. Why is this? What is it about the diets of dif-
ferent fish species—such as tilapia or salmon—that make the farming of one more
sustainable than the other? How might you use that knowledge to build a sustainable
aquaculture system?

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agflation An increase in the price of food
that occurs as a result of increased demand
from human consumption.

agroecology An ecological approach to
agriculture that views agricultural areas as
ecosystems and is concerned with the eco-
logical impact of agricultural practices.

apex the top or highest part of something.

apex predators Predators that feed at the
very top of the food chain.

aquaculture the growing and harvesting of
fish and shellfish for human use.

biofuels Gas or liquid fuels made from plant
material.

Dust Bowl the ecological and agricultural
damage in the American Plains created by
the severe dust storms of the 1930s; for
more information, visit http://www.pbs
.org/wgbh/americanexperience/films
/dustbowl.

food miles the measure of how far food
travels on average from where it is produced
to where it is consumed.

genetic engineering the deliberate modi-
fication of the characteristics of an organism
by manipulating its genetic material.

Global Food Price Index A measure of the
monthly change in international prices of a
basket of food commodities, specifically the
prices of cereal, oils/fats, sugar, dairy, and
meat.

green revolution term for the introduction
of scientifically bred or selected varieties of
grain that, with adequate inputs of fertilizer
and water, can greatly increase crop yields.

locavore one who primarily eats food that
is grown or produced within the local com-
munity or region.

Malthusian correction theory put forth
by the reverend thomas robert Malthus
(1766–1834) that population growth is
eventually curtailed by famine, disease, or
other factors.

monocultures cultivation of a single crop,
usually on a large area of land.

seafood print A measure of the amount of
primary production—microscopic organ-
isms at the bottom of the marine food web—
required to make a pound of a given type of
fish.

7. the idea of using food miles as a key indicator of the environmental impact of a
certain food product has recently come under attack as being oversimplified. crit-
ics point out that it’s not just how far a food item travels that determines how much
energy is used to bring it to market, but also how much energy is used, and how effi-
ciently it’s used, to produce it in the first place. If you had to design an experiment to
estimate the life cycle energy costs (how much energy is used in the entire process
of producing and transporting a product to market) of an apple grown 1,500 miles
away on a large apple farm versus one grown locally by a small farmer, how would
you do it? What factors would you want to consider in making this comparison?

Key terms

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Additional resources
the following links are useful to learn more about the history, science, and impacts (positive
and negative) of the green revolution:

• http://www.ars.usda.gov/is/timeline/green.htm
• http://www.ifpri.org/sites/default/files/pubs/pubs/ib/ib11

Here are a number of very useful sources for understanding the basic concepts behind sus-
tainable agriculture, agroecology, and organic agriculture:

• From the u.S. Department of Agriculture:
❍ http://www.nal.usda.gov/afsic/pubs/terms/srb9902.shtml
❍ http://www.nal.usda.gov/afsic/pubs/agnic/susag.shtml
❍ http://afsic.nal.usda.gov/sustainability-agriculture-0
❍ http://www.ers.usda.gov/amber-waves.aspx

• other useful readings:
❍ http://agroeco.org/socla/wp-content/uploads/2013/12/wezel-agro

ecology
❍ http://nature.berkeley.edu/~miguel-alt/
❍ http://www.thesolutionsjournal.com/node/971
❍ http://cedarcreek.umn.edu/biblio/fulltext/nature10452
❍ http://e360.yale.edu/feature/the_folly_of_big_agriculture_why

_nature_always_wins/2514/
❍ http://e360.yale.edu/feature/can_reforming_the_farm_bill_help

_change_us_agriculture/2508/
❍ http://e360.yale.edu/feature/helping_us_farmers_increase

_production_and_protect_the_land/2549/

not surprisingly, there is a wealth of information on the subject of genetically modified (GM)
foods. A good starting point is the noVA/Frontline special report titled Harvest of Fear.
Besides basic background information on the concept, the site includes activities that allow
you to design your own GM crop.

• http://www.pbs.org/wgbh/harvest/
• http://www.pbs.org/wgbh/harvest/engineer/
• http://www.pbs.org/wgbh/harvest/coming/
• http://www.pbs.org/wgbh/harvest/viewpoints/

other useful sites, stories, and resources on GM crops and the controversies surrounding
genetic engineering of foods include the following:

• http://www.nature.com/news/specials/gmcrops/index.html
• http://www.nytimes.com/2013/08/25/sunday-review/golden-rice-lifesaver.html
• http://grist.org/food/golden-rice-fools-gold-or-golden-opportunity/
• http://www.nytimes.com/2013/07/28/science/a-race-to-save-the-orange-by

-altering-its-dna.html
• http://www.michaelspecter.com/wp-content/uploads/pharmageddon
• http://www.elle.com/beauty/health-fitness/allergy-to-genetically-modified-corn
• http://www.brown.edu/ce/adult/arise/resources/docs/yw10_1

ben85927_03_c03.indd 139 1/20/14 2:29 PM

http://www.ars.usda.gov/is/timeline/green.htm

http://www.ifpri.org/sites/default/files/pubs/pubs/ib/ib11

http://www.nal.usda.gov/afsic/pubs/terms/srb9902.shtml

http://www.nal.usda.gov/afsic/pubs/agnic/susag.shtml

http://afsic.nal.usda.gov/sustainability-agriculture-0

http://www.ers.usda.gov/amber-waves.aspx

http://agroeco.org/socla/wp-content/uploads/2013/12/wezel-agroecology

http://nature.berkeley.edu/~miguel-alt/

http://www.thesolutionsjournal.com/node/971

http://cedarcreek.umn.edu/biblio/fulltext/nature10452

http://e360.yale.edu/feature/the_folly_of_big_agriculture_why_nature_always_wins/2514/

http://e360.yale.edu/feature/can_reforming_the_farm_bill_help_change_us_agriculture/2508/

http://e360.yale.edu/feature/helping_us_farmers_increase_production_and_protect_the_land/2549/

http://www.pbs.org/wgbh/harvest/

http://www.pbs.org/wgbh/harvest/engineer/

http://www.pbs.org/wgbh/harvest/coming/

http://www.pbs.org/wgbh/harvest/viewpoints/

http://www.nature.com/news/specials/gmcrops/index.html

http://www.nytimes.com/2013/08/25/sunday-review/golden-rice-lifesaver.html

http://grist.org/food/golden-rice-fools-gold-or-golden-opportunity/

http://www.nytimes.com/2013/07/28/science/a-race-to-save-the-orange-by-altering-its-dna.html

http://www.michaelspecter.com/wp-content/uploads/pharmageddon

http://www.elle.com/beauty/health-fitness/allergy-to-genetically-modified-corn

http://www.brown.edu/ce/adult/arise/resources/docs/yw10_1

SuMMArY & rESourcES

• http://www.who.int/foodsafety/biotech/en/
• http://e360.yale.edu/feature/why_i_still_oppose_genetically_modified_crops/2191/
• http://e360.yale.edu/digest/growing_number_of_pests_developing_resistance_to

_gm_crops/3866/
• http://e360.yale.edu/digest/increase-in-gm-crops-leads-to-jump-in-herbicide

-use/2149/
• http://e360.yale.edu/digest/scientists-find-first-evidence—of-gm-crops-reproducing

-in-the-wild/2538/
• http://e360.yale.edu/digest/genetically-modified-crops-needed-to-avert-food

-crisis-panel-says/2110/
• http://e360.yale.edu/digest/farmer-groups-protest—indias-first-genetically

-modified-food-crop/2168/

Information on the environmental and health impacts of our meat-based diet can be found at
the following links:

• http://www.nytimes.com/2008/01/27/weekinreview/27bittman.html?_r=0
• http://www.nytimes.com/imagepages/2008/01/27/weekinreview/20080127

_BIttMAn1_GrAPHIc.html
• http://www.nytimes.com/imagepages/2008/01/27/weekinreview/20080127

_BIttMAn2_GrAPHIc.html
• http://chartsbin.com/view/bhy
• http://www.npr.org/blogs/thesalt/2012/06/26/155720538/the-making-of-meat

-eating-america
• http://www.npr.org/blogs/thesalt/2012/06/27/155527365/visualizing-a-nation

-of-meat-eaters
• http://www.pewtrusts.org/uploadedFiles/wwwpewtrustsorg/reports/Industrial

_Agriculture/PcIFAP_FInAL

Information on the concept of food miles, including a number of different ways in which you
can measure the food miles of foods you typically consume, can be found here:

• http://www.pbs.org/e2/teachers/teacher_food_miles_project.html
• http://www.pbs.org/e2/teachers/teacher_309.html
• http://lifecyclesproject.ca/initiatives/food_miles/
• http://blogs.cce.cornell.edu/franklin/agriculture-program/ag-economic-development

/food-miles-tools/
• http://www.fallsbrookcentre.ca/cgi-bin/calculate.pl

Interesting information on the growing interest in urban agriculture can be found here:

• http://afsic.nal.usda.gov/farms-and-community/urban-agriculture
• http://www.ruaf.org/node/512
• http://topics.nytimes.com/top/reference/timestopics/subjects/a/agriculture

/urban_agriculture/index.html
• http://www.epa.gov/brownfields/urbanag/
• http://auachicago.org
• http://environment.nationalgeographic.com/environment/photos/urban-farming/
• http://www.urbanfarming.org

ben85927_03_c03.indd 140 1/20/14 2:29 PM

http://www.who.int/foodsafety/biotech/en/

http://e360.yale.edu/feature/why_i_still_oppose_genetically_modified_crops/2191/

http://e360.yale.edu/digest/growing_number_of_pests_developing_resistance_to_gm_crops/3866/

http://e360.yale.edu/digest/increase-in-gm-crops-leads-to-jump-in-herbicide-use/2149/

http://e360.yale.edu/digest/scientists-find-first-evidence-of-gm-crops-reproducing-in-the-wild/2538/

http://e360.yale.edu/digest/genetically-modified-crops-needed-to-avert-food-crisis-panel-says/2110/

http://e360.yale.edu/digest/farmer-groups-protest-indias-first-genetically-modified-food-crop/2168/

http://www.nytimes.com/2008/01/27/weekinreview/27bittman.html?_r=0

http://www.nytimes.com/imagepages/2008/01/27/weekinreview/20080127_BITTMAN1_GRAPHIC.html

http://www.nytimes.com/imagepages/2008/01/27/weekinreview/20080127_BITTMAN2_GRAPHIC.html

http://chartsbin.com/view/bhy

http://www.npr.org/blogs/thesalt/2012/06/26/155720538/the-making-of-meat-eating-america

http://www.npr.org/blogs/thesalt/2012/06/27/155527365/visualizing-a-nation-of-meat-eaters

http://www.pewtrusts.org/uploadedFiles/wwwpewtrustsorg/Reports/Industrial_Agriculture/PCIFAP_FINAL

http://www.pbs.org/e2/teachers/teacher_food_miles_project.html

http://www.pbs.org/e2/teachers/teacher_309.html

http://lifecyclesproject.ca/initiatives/food_miles/

http://blogs.cce.cornell.edu/franklin/agriculture-program/ag-economic-development/food-miles-tools/

http://www.fallsbrookcentre.ca/cgi-bin/calculate.pl

http://afsic.nal.usda.gov/farms-and-community/urban-agriculture

http://www.ruaf.org/node/512

http://topics.nytimes.com/top/reference/timestopics/subjects/a/agriculture/urban_agriculture/index.html

http://www.epa.gov/brownfields/urbanag/

http://auachicago.org

http://environment.nationalgeographic.com/environment/photos/urban-farming/

http://www.urbanfarming.org

SuMMArY & rESourcES

A 30-minute expert discussion of the future of the world’s fisheries can be found here:

• http://www.npr.org/templates/story/story.php?storyId=6469061

A very interesting Katie couric interview on Americans and food can be found here:

• http://www.youtube.com/watch?v=7prLrgbojZg

ben85927_03_c03.indd 141 1/20/14 2:29 PM

http://www.npr.org/templates/story/story.php?storyId=6469061

ben85927_03_c03.indd 142 1/20/14 2:29 PM

V. Muthuraman/SuperStock

Learning Objectives

After studying this chapter, you should be able to:

• Explain how the hydrological or water cycle works and describe how water is distributed among differ-
ent spheres of the planet—oceans, glaciers, ice and snow, groundwater, rivers, streams, lakes, wetlands,
and water vapor in the atmosphere.

• Describe the major categories of freshwater use by humans, both extractive and non-extractive, and how
overuse and misuse of water resources in some regions is threatening the future sustainability of water
supplies.

• Describe how diversion of water for human uses, destruction of wetland habitats, and pollution of natu-
ral waterways is already causing severe water shortages in places like China, the Aral Sea Basin, central
Africa, and Mexico.

• Understand the basic difference between supply-side or hard-path solutions that seek to develop new
supplies of water and demand-side or soft-path solutions that emphasize water conservation and
greater efficiency in use.

• Explain the causes for the decline of the Jordan River and how political conflict between nations can be a
complicating factor in efforts to protect water supplies and restore endangered ecosystems.

Water 5

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IntRoDUCtIon

Pre-Test

1. A scientist who studies the movement, storage, and distribution of water is called a
hydrolysist.

a. true
b. False

2. Which of the following is not a major category of human water use?
a. Industry
b. Agriculture
c. transportation
d. Residential

3. During the 20th century, the world population tripled, while water use per person

increased by six times.
a. true
b. False
4. the “supply-side” approach to water conservation emphasizes water-saving techniques

and reducing demand.
a. true
b. False
5. the Friends of the Earth Middle East plan for restoring the Jordan River represents a

“hard-path” approach to water management.
a. true
b. False

Introduction
When viewed from space, Earth is a watery planet. Indeed, oceans comprise about 71 percent
of our planet’s surface, while glistening glaciers cover 10 percent of the continents. Yet water
shortages are a serious problem. this contradiction is due, in part, to the fact that the abun-
dance of ocean water is too salty for human use, and much of the remaining freshwater is pol-
luted, used up, or distributed unequally. As summed up by one prominent ecologist, “the wet
places in the world don’t need the runoff because they are wet. the dry places of the world
need the runoff to irrigate the land, but they don’t get much” (Pimm, 2001).

Globally, humans extract about one-sixth of the total volume of all the rivers in the world.
But the amount of consumption varies from place to place. In British Columbia, for example,
winter snowfall and summer rain are abundant and the population density is low. thus, rivers
carry copious amounts of water into the oceans. on the other hand, in the southwest desert of

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SECtIon 5.1 WAtER SUPPlY AnD thE hYDRoloGICAl CYClE

the United States, precipitation is low and the population is much larger, so the consumption
of freshwater outpaces its replenishment. As a result, the Colorado River, which meanders
through the American southwest and into Mexico, no longer reaches the ocean. Instead, much
of the water from the once free-flowing Colorado River is diverted and extracted to irrigate
the parched landscape. And whereas in the past water from the Colorado River used to reach
communities in Mexico, today those areas only receive a trickle of salty river water.

Massive diversion and use of water from the Colorado River on the American side of the U.S.-
Mexico border is a source of tension between the two countries. And while this tension is
serious enough, it involves two relatively friendly allies and trading partners. the situation is
significantly different in more volatile regions of the world such as the Middle East where con-
flicts over water are potentially explosive. the Jordan River, for example, is a source of water
for Jordan, Syria, Israel, and the Palestinian territories. Water is a critically scarce resource in
this region and population growth, climate change, and water pollution and misuse are mak-
ing it even scarcer. As a result, water issues have and will continue to feature as a key factor in
regional political negotiations and disputes.

Given its importance, it is remarkable how poorly managed water is as a resource. We regu-
larly use rivers, lakes, and the oceans as a dumping ground for our wastes and allow surface
contaminants such as spilled oil and agricultural chemicals to pollute critical groundwater
supplies. Water is diverted and pumped hundreds of miles (requiring significant levels of
energy use) to irrigate golf courses and suburban lawns in the middle of deserts. And, as
we’ll see in the next chapter, massive quantities of water are necessary to extract energy from
unconventional oil and gas deposits. Where our water comes from, how we use (and abuse)
this critical resource, and what we can do to better conserve and protect it is the focus of
this chapter. We already know that a growing human population and the demands of feeding
the world are putting increased pressure on water resources. We’ll see in Chapter 7 that cli-
mate change could also worsen already-critical water supply conditions in some regions. As
a result, everything we can do now to minimize water contamination, pollution, and overuse
is essential. the Working Toward Solutions section at the end of this chapter thus provides a
wealth of advice and information on how we can do just that.

5.1 Water Supply and the Hydrological Cycle
The hydrological or water cycle describes the movement and storage of water between different
spheres on the planet. At any point in time water may be stored in the oceans, glaciers, and ice
and snow; as groundwater; in rivers, streams, lakes, ponds, and wetlands; and lastly, as water
vapor in the atmosphere. Water is constantly moving between these spheres through the pro-
cesses of evaporation, precipitation, infiltration, melting, and groundwater flow. Only 3 percent
of the Earth’s water is freshwater (not salty), and close to 70 percent of that freshwater is frozen
in ice caps at the poles and in glaciers. Therefore, we are ultimately dependent for our survival
on a small but critical portion of the overall planetary water cycle. In the first part of this Eco-
logical Society of America (ESA) report written by ecologist Robert B. Jackson and co-authors,
we see just how massive and important the water cycle actually is.

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SECtIon 5.1 WAtER SUPPlY AnD thE hYDRoloGICAl CYClE

Beyond our obvious uses of freshwater for drinking, bathing, and washing, our society makes
use of water for many other purposes. Scientists break these uses down into categories known
as consumptive and instream. Consumptive (or extractive) uses involve removing water from its
source for drinking or other residential purposes as well as for industrial use and irrigation of
crops. Instream (or non-extractive) uses involve deriving benefits from water without remov-
ing it from where it is located. Examples of instream uses include transportation/navigation,
recreation, habitat for fish and other aquatic life, hydroelectric power generation, and waste
processing. The sustainable management of water supplies frequently involves tradeoffs and/
or conflicts between consumptive and instream uses. This was dramatically illustrated in recent
years in the Pacific Northwest when irrigation water from rivers was denied to farmers in order
to maintain water levels needed for salmon populations.

In addition to surface water management there are also concerns over how groundwater
resources are managed. Hydrologists (scientists who study the movement and distribution of
water) make a distinction between renewable and nonrenewable groundwater. Over three-
fourths of all underground water is considered nonrenewable since it is found in aquifers that
formed tens of thousands of years ago. Since these aquifers are not replenished by rainfall on
the surface, over-extraction of water from them is not sustainable. A primary example of non-
renewable groundwater or a “fossil water” source is the Ogallala Aquifer in the central United
States where rapid pumping of water to irrigate Midwestern farmland has lowered the level of
the aquifer significantly.

In contrast, renewable groundwater refers to aquifers that are regularly replenished by rainfall
or snowmelt. Even though groundwater resources are renewable, they can be seriously misman-
aged. Examples include when water is removed faster than it is replenished and when pollutants
or waste products from the surface are allowed to seep into it. Renewable groundwater deposits
can be thought of as bank accounts. As long as we do not withdraw more than is going in, we
can maintain a positive balance. Nonrenewable groundwater is better thought of as a one-time
inheritance or windfall that we can make use of but only at the expense of lower future balances.

A better understanding of the water cycle gained in this section sets the stage for a discussion
of water use and misuse in subsequent sections of the chapter. It also will help you understand
why water pollution is such a critical environmental issue and why efforts to promote water
conservation are so important.

By R.B. Jackson, et al.
life on earth depends on the continuous flow of materials through the air, water, soil, and food
webs of the biosphere. the movement of water through the hydrological cycle comprises
the largest of these flows, delivering an estimated 110,000 cubic kilometers (km3) of water
to the land each year as snow and rainfall [a cubic kilometer is an area 1,000 meters wide
by 1,000 meters deep by 1,000 meters high, or roughly 10 football fields across, deep, and
tall]. Solar energy drives the hydrological cycle, vaporizing water from the surface of oceans,
lakes, and rivers as well as from soils and plants (evapotranspiration). Water vapor rises into
the atmosphere where it cools, condenses, and eventually rains down anew. this renewable
freshwater supply sustains life on the land, in estuaries, and in the freshwater ecosystems of
the Earth.

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SECtIon 5.1 WAtER SUPPlY AnD thE hYDRoloGICAl CYClE

Figure 5.1: Hydrological cycle

the hydrological, or water, cycle collects and distributes Earth’s fixed supply of water through the
processes of evaporation, evapotranspiration, and precipitation.

Based on information from U.S.G.S. Retrieved from ga.water.usgs.gov/edu/watercycle.html

Renewable fresh water provides many services essential to human health and well being,
including water for drinking, industrial production, and irrigation, and the production of
fish, waterfowl, and shellfish. Fresh water also provides many benefits while it remains in
its channels (nonextractive or instream benefits), including flood control, transportation,
recreation, waste processing, hydroelec-
tric power, and habitat for aquatic plants
and animals. Some benefits, such as irri-
gation and hydroelectric power, can be
achieved only by damming, diverting, or
creating other major changes to natural
water flows. Such changes often diminish
or preclude other instream benefits of
fresh water, such as providing habitat for
aquatic life or maintaining suitable water
quality for human use.

Condensation

Evaporation

Water

storage

in oceans

Groundwater storage

Groundwat

discharge

Snowmelt
runoff to
streams

Precipitation

Spring
Freshwater

storage

Plant
uptake

Evaporation
Stream

flow

Surface
runoff

Water storage
in ice and snow

Water
storage in the

atmosphere

Infiltration

Evapotranspiration

Water storage
in ice and snow

Consider This
What is the difference between extractive
and non-extractive or instream uses of
freshwater? how might these different uses
come into conflict with one another?

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ga.water.usgs.gov/edu/watercycle.html

SECtIon 5.1 WAtER SUPPlY AnD thE hYDRoloGICAl CYClE

the ecological, social, and economic benefits that freshwater systems provide, and the trade-
offs between consumptive and instream values, will change dramatically in the coming cen-
tury. Already, over the past one hundred years, both the amount of water humans withdraw
worldwide and the land area under irrigation have risen exponentially. Despite this greatly
increased consumption, the basic water needs of many people in the world are not being met.
Currently, 1.1 billion people lack access to safe drinking water, and 2.8 billion lack basic sani-
tation services. these deprivations cause approximately 250 million cases of water-related
diseases and five to ten million deaths each year. Also, current unmet needs limit our ability
to adapt to future changes in water supplies and distribution. Many current systems designed
to provide water in relatively stable climatic conditions may be ill prepared to adapt to future
changes in climate, consumption, and population. While a global perspective on water with-
drawals is important for ensuring sustainable water use, it is insufficient for regional and
local stability. how fresh water is managed in particular basins and in individual watersheds
is the key to sustainable water management.

The Global Water Cycle

Surface Water
Most of the earth is covered by water, more than one billion km3 of it. the vast majority of that
water, however, is in forms unavailable to land-based or freshwater ecosystems. less than
3 percent is fresh enough to drink or to irrigate crops, and of that total, more than two-thirds
is locked in glaciers and ice caps. Freshwater lakes and rivers hold 100,000 km3 globally, less
than one ten-thousandth of all water on earth.

Water vapor in the atmosphere exerts an important influence on climate and on the water
cycle, even though only 15,000 km3 of water is typically held in the atmosphere at any time.
this tiny fraction, however, is vital for the biosphere. Water vapor is the most important of
the so-called greenhouse gases (others include carbon dioxide, nitrous oxide, and methane)
that warm the earth by trapping heat in the atmosphere. Water vapor contributes approxi-
mately two-thirds of the total warming that greenhouse gases supply. Without these gases,
the mean surface temperature of the earth would be well below freezing, and liquid water
would be absent over much of the planet. Equally important for life, atmospheric water turns
over every ten days or so as water vapor condenses and rains to earth and the heat of the sun
evaporates new supplies of vapor from the liquid reservoirs on earth.

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SECtIon 5.1 WAtER SUPPlY AnD thE hYDRoloGICAl CYClE

Figure 5.2: Earth’s water distribution

Although Earth is considered a “watery planet,” only about 3 percent of Earth’s water is fresh, and
much of that is locked up in ice caps and glaciers. Since life on Earth depends on this limited supply
of water, it is critical to learn to use it in a sustainable manner.

Based on information from U.S.G.S. Retrieved from http://ga.water.usgs.gov/edu/mearthall.html

Solar energy typically evaporates about 425,000 km3 of ocean water each year. Most of
this water rains back directly to the oceans, but approximately 10 percent falls on land. If
this were the only source of rainfall, average precipitation across the earth’s land surfaces
would be only 25 centimeters (cm) a year, a value typical for deserts or semi-arid regions.
Instead, a second, larger source of water is recycled from plants and the soil through
evapotranspiration. the water vapor from this source creates a direct feedback between
the land surface and regional climate. the cycling of other materials such as carbon and
nitrogen (biogeochemical cycling) is strongly coupled to this water flux through the pat-
terns of plant growth and microbial decomposition, and this coupling creates additional
feedbacks between vegetation and climate. this second source of recycled water contributes
two-thirds of the 70 cm of precipitation that falls over land each year. taken together, these
two sources account for the 110,000 km3 of renewable freshwater available each year for
terrestrial, freshwater, and estuarine ecosystems.

Fresh water

E
ar

th
’s

w
at

Other
.09%

Saline
(oceans)

97%

Saline
(oceans)
97%

Ground water
30.1%

Ice caps and glaciers
68.7%

Fresh surface
water (liquid)

Rivers

Swamps

Lakes

11%

87%

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http://ga.water.usgs.gov/edu/mearthall.html

SECtIon 5.1 WAtER SUPPlY AnD thE hYDRoloGICAl CYClE

Because the amount of rain that falls on land is greater than the amount of water that evapo-
rates from it, the extra 40,000 km3 of water returns to the oceans, primarily via rivers and
underground aquifers. A number of factors affect how much of this water is available for
human use on its journey to the oceans. these factors include whether the precipitation falls
as rain or snow, the timing of precipitation relative to patterns of seasonal temperature and
sunlight, and the regional topography. For example, in many mountain regions, most precipi-
tation falls as snow during winter, and spring snowmelt causes peak flows that flood major
river systems. In some tropical regions, monsoons rather than snowmelt create seasonal
flooding. In other regions, excess precipitation percolates into the soil to recharge ground
water or is stored in wetlands. Widespread loss of wetlands and floodplains, however, reduces
their ability to absorb these high flows and speeds the runoff of excess nutrients and contami-
nants to estuaries and other coastal environments. More than half of all wetlands in the U. S.
have already been drained, dredged, filled, or planted.

Available water is not evenly distributed globally. two thirds of all precipitation falls in the
tropics (between 30 degrees n and 30 degree S latitude) due to greater solar radiation and
evaporation there. Daily evaporation from the oceans ranges from 0.4 cm at the equator to
less than 0.1 cm at the poles. typically, tropical regions also have larger runoff. Roughly half
of the precipitation that falls in rainforests becomes runoff, while in the deserts low rainfall
and high evaporation rates combine to greatly reduce runoff. the Amazon, for example, car-
ries 15 percent of all water returning to the global oceans. In contrast, the Colorado River
drainage, which is one-tenth the size of the Amazon, has a historic annual runoff 300 times
smaller. Similar variation occurs at continental scales. Average runoff in Australia is only 4 cm
per year, eight times less than in north America and orders of magnitude less than in tropical
South America.

As a result of these and many other disparities, freshwater availability varies dramatically
worldwide.

Ground Water
Approximately 99 percent of all liquid fresh water is in underground aquifers, and at least
a quarter of the world’s population draws its water from these groundwater supplies. Esti-
mates of the global water cycle generally treat rates of groundwater inflow and outflow as if
they were balanced. In reality, however, this resource is being depleted globally. Ground water
typically turns over more slowly than most other water pools, often in hundreds to tens of
thousands of years, although the range in turnover rates is large. Indeed, a majority of ground
water is not actively turning over or being recharged from the earth’s surface at all. Instead, it
is “fossil water,” a relic of wetter ancient climatic conditions and melting Pleistocene ice sheets
that accumulated over tens of thousands of years. once used, it cannot readily be replenished.

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SECtIon 5.1 WAtER SUPPlY AnD thE hYDRoloGICAl CYClE

the distinction between renewable and nonrenewable ground water is critical for water
management and policy. More than three-quarters of underground water is non-renewable,
meaning it has a replenishment period of centuries or more. the high Plains or ogallala Aqui-
fer that underlies half a million km2 of the central United States is arguably the largest aquifer
in the world. the availability of turbine pumps and relatively inexpensive energy has spurred
the drilling of about 200,000 wells into the aquifer since the 1940s, making the ogallala the
primary water source for a fifth of irrigated U.S. farmland. the extent of irrigated cropland
in the region peaked around 1980 at 5.6 million hectares and at pumping rates of about
6 trillion gallons of water a year. that has since declined somewhat due to groundwater deple-
tion and socioeconomic changes in the region. however, the average thickness of the ogallala
declined by more than 5 percent across a fifth of its area in the 1980s alone.

In contrast, renewable aquifers depend on current rainfall for refilling and so are vulnerable to
changes in the quantity and quality of recharge water. For example, groundwater pumping of
the Edwards Aquifer, which supplies much of central texas with drinking water, has increased
four-fold since the 1930s and at times now exceeds annual recharge rates. Increased water
withdrawal makes aquifers more susceptible to drought and other changes in weather and to
contamination from pollutants and wastes that percolate into the ground water. Depletion of
ground water can also cause land subsidence [to sink] and compaction [consolidation of sedi-
ments] of the porous sand, gravel, or rock of the aquifer, permanently reducing its capacity
to store water. the Central Valley of California has lost about 25 km3 of storage in this way, a
capacity equal to more than 40 percent of the combined storage capacity of all human-made
reservoirs in the state.

Renewable ground water and surface waters have commonly been viewed separately, both
scientifically and legally. this view is changing, however, as studies in streams, rivers, reser-
voirs, wetlands, and estuaries show the importance of interactions between renewable sur-
face and ground waters for water supply, water quality, and aquatic habitats. Where extraction
of ground water exceeds recharge rates, the result is lower water tables. In summer, when a
high water table is needed to sustain minimum flows in rivers and streams, low groundwater
levels can decrease low-flow rates, reduce perennial stream habitat, increase summer stream
temperatures, and impair water quality. trout and salmon species select areas of ground-
water upwelling in streams to moderate extreme seasonal temperatures and to keep their
eggs from overheating or freezing. Dynamic exchange of surface and ground waters alters
the dissolved oxygen and nutrient concentrations of streams and dilutes concentrations of
dissolved contaminants such as pesticides and volatile organic compounds. Because of such
links, human development of either ground water or surface water often affects the quantity
and quality of the other.

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SECtIon 5.1 WAtER SUPPlY AnD thE hYDRoloGICAl CYClE

Figure 5.3: Interaction between groundwater and surface water

In Earth’s hydrological cycle, precipitation not only sustains ecosystems and human activity, but
also recharges shallow and deep aquifers. the remaining water returns to the atmosphere via
evapotranspiration. human industrial, agricultural, and municipal users are using groundwater
faster than it can be recharged, resulting in depletion of this precious natural resource. A major
cause of freshwater depletion is that most groundwater is not actively recharged. Instead, it is “fossil”
water—a relic of wetter ancient climatic conditions.

Based on information from U.S.G.S. Retrieved from http://pubs.usgs.gov/circ/circ1139/htdocs/natural_processes_of_ground
.htm#lakes

the links between surface and ground waters are especially important in regions with low
rainfall. Arid and semi-arid regions cover a third of the earth’s lands and hold a fifth of the
global population. Ground water is the primary source of water for drinking and irrigation in
these regions, which possess many of the world’s largest aquifers. limited recharge makes
such aquifers highly susceptible to groundwater depletion. For example, exploitation of the
northern Sahara Basin Aquifer in the 1990s was almost twice the rate of replenishment, and
many springs associated with this aquifer are drying up. For non-renewable groundwater
sources, discussing sustainable or appropriate rates of extraction is difficult. As with depos-
its of coal and oil, almost any extraction is non-sustainable. Important questions for society
include at what rate groundwater pumping should be allowed, for what purpose, and who if
anyone will safeguard the needs of future generations. In the ogallala Aquifer, for example,
the water may be gone in as little as a century.

Adapted from Jackson, R.B., et al. (2001). Water in a Changing World. Ecological Society of America, Issues in
Ecology, number 9. Retrieved from http://www.esa.org/esa/wp-content/uploads/2013/03/issue9 . Used
with permission.

Groundwater flow

Surface runoff
Snow
runoff

Well

Groundwater
flow

Lake

Groundwater
discharge

Evapotranspiration

Water table

Condensation
Precipitation
Groundwater
discharge

Hydrologic
Cycle

Ev
ap

or
at

io
n

Cond
ensation

Precipitation

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http://pubs.usgs.gov/circ/circ1139/htdocs/natural_processes_of_ground.htm#lakes

http://www.esa.org/esa/wp-content/uploads/2013/03/issue9

SECtIon 5.2 WAtER AVAIlABIlItY AnD DEMAnD

5.2 Water Availability and Demand
In this continuation of the Ecological Society of America report by ecologist Robert B. Jackson
and co-authors, we see how human demand and use accounts for over half of all accessible fresh-
water runoff on the planet. Water demand is broken into three broad categories: agricultural,
industrial/commercial, and residential. Of these three, water use for agriculture accounts for
the greatest share. Because freshwater supplies are not distributed evenly around the planet,
and also because population and the demand for water continues to increase, meeting our need
for water in all applications is a growing challenge.

Even as the global population continues to rise to nine billion or more, we are already seeing
a shortage of freshwater in some regions of the world. Over one billion people currently lack
access to adequate and safe water supplies, and as many as three billion lack access to proper
sanitation. As a result, an estimated five million preventable deaths occur each year from water-
related diseases that mostly claim the lives of young children. In some cases, problems arise from
an absolute scarcity of water, whereas in others there is an absence of adequate infrastructure
to meet a population’s water requirements.

Theoretically, a region’s water demand can be met sustainably by using renewable groundwa-
ter supplies, exploiting river flow, or capturing and storing floodwater and snowmelt behind
dams in reservoirs. However, evidence from around the world suggests that in many places
these resources are not being managed sustainably. For example, the over-pumping of water for
irrigation results in groundwater depletion in key regions of India, China, and North America.
Diversion of surface/river waters for irrigation and other consumptive uses alters entire ecosys-
tems, such as the Colorado River. An even more dramatic example is the Aral Sea Basin in Asia
where large-scale diversions have caused the depth of one large lake to drop 50 feet in 40 years
while the remaining water has become saltier than the ocean. Lastly, dams and reservoirs can
address some water needs in some places, but these projects are expensive and can create their
own ecological and social problems. With climate change and population growth already wors-
ening water supply and management issues, the prevention of water pollution and promotion of
water conservation practices takes on an even more urgent priority.

By R.B. Jackson, et al.
Growth in global population and water consumption will place additional pressure on fresh-
water resources in the coming century. Currently, the water cycle makes available several
times more fresh water each year than is needed to sustain the world’s population of six bil-
lion people [now over seven billion]. however, the distribution of this water, both geographi-
cally and temporally, is not well matched to human needs. the large river flows of the Amazon
and Zaire-Congo basins and the tier of undeveloped rivers in the northern tundra and taiga
regions of Eurasia and north America are largely inaccessible for human uses and will likely
remain so for the foreseeable future. together, these remote rivers account for nearly one-
fifth of total global runoff.

Approximately half of the global renewable water supply runs rapidly toward the sea in floods.
In managed river systems of north America and many other regions, spring floodwaters from
snowmelt are captured in reservoirs for later use. In tropical regions, a substantial share of
annual runoff occurs during monsoon flooding. In Asia, for example, 80 percent of runoff
occurs between May and october. Although this floodwater provides a variety of ecological
services, including sustaining wetlands, it is not a practical supply for irrigation, industry, and
household uses that need water to be delivered in controlled quantities at specific times.

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thus, there are two categories of accessible runoff available to meet human water needs:
(1) renewable ground water and base river flow, and (2) floodwater that is captured and
stored in reservoirs. Base river flows and renewable ground water account for about 27 per-
cent of global runoff each year. As long as the rate of water withdrawals does not exceed
replenishment by rainfall, these sources can serve as a sustainable supply. Unfortunately,
in many places, including many important agricultural regions, ground water is chronically
overpumped. Data for China, India, north Africa, Saudi Arabia, and the United States indi-
cate that groundwater depletion in key basins totals at least 160 km3 per year. Groundwater
depletion is particularly serious in India, and some water experts have warned that as much
as one-fourth of India’s grain harvest could be jeopardized by overpumping. the fact that
global groundwater extractions remain well below the global recharge rate does not mean
that groundwater use in a specific region is sustainable. What matters is how water is used
and managed in particular basins, and there are many regions of the world where current
demand outstrips supply.

Figure 5.4: Actual global renewable water resources per capita

Actual global renewable water resources per capita based on 2009 data.

Based on data from U.N. Water, Federated Water Monitoring System and Key Water Indicator Portal. Retrieved from http://www
.unwater.org/statistics_KWIP.html

turning floodwater into an accessible supply generally requires dams and reservoirs to cap-
ture, store, and control the water. Worldwide, there are approximately 40,000 large dams
more than 15 meters (m) high and twenty times as many smaller dams. Collectively, the
world’s reservoirs can hold an estimated 6,600 km3 of water each year. Considerably less
water than this is delivered to farms, industries, and cities, however, because dams and reser-
voirs are also used to generate electricity, control floods, and enhance river navigation.

> 6000

500−1000

1700−6000 1000−1700

0−500 Data Unavailable

Cubic meters per person in 2009

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http://www.unwater.org/statistics_KWIP.html

SECtIon 5.2 WAtER AVAIlABIlItY AnD DEMAnD

Finally, after subtracting remote rivers from base flows and discounting reservoir capacity
allocated to functions other than water supply, the total accessible runoff available for human
use is about 12,500 km3 per year, or 31 percent of total annual runoff.

Human Water Use
People use fresh water for many purposes. there are three broad categories of extractive uses
for which people withdraw water from its natural channel or basin: irrigation of crops, indus-
trial and commercial activities, and residential life. In many cases, water can be used more
than once after it is withdrawn. Water that is used but not physically consumed—to wash
dishes, for example—may be used again, although it sometimes requires further treatment.
In contrast, about half the water diverted for irrigation is lost through evapotranspiration and
is unavailable for further use.

Excessive rates of consumptive water use can have extreme effects on local and regional
ecosystems. In the Aral Sea Basin [in central Asia between Kazakhstan and Uzbekistan], for
example, large river diversions for irrigation have caused the lake to shrink more than three
quarters in volume and fifteen meters in depth over the past four decades. the shoreline
of the Aral Sea has retreated 120 km in places, and a commercial fishery that once landed
45,000 tonnes [tons] a year and employed 60,000 people has disappeared. Water quality has
also declined. Salinity [saltiness] tripled from 1960 to 1990, and the water that remains is
now saltier than the oceans.

For purposes of water management, the difference between use and consumption is impor-
tant. Global withdrawals of water (including evaporative losses from reservoirs) total
4,430 km3 a year, and 52 percent of that is consumed. Water use or withdrawal also modifies
the quality of the remaining water in a basin or channel by increasing concentration of major
ions, nutrients, or contaminants. As the example of the Aral Sea showed, this effect can limit
the suitability of water for future use.

In addition to water removed from natural systems, human enterprises depend heavily on
water that remains in its natural channels. these instream uses include dilution of pollutants,
recreation, navigation, maintenance of healthy estuaries, sustenance of fisheries, and protec-
tion of biodiversity. Because instream uses of water vary by region and season, it is difficult
to estimate their global total. If pollution dilution is taken as a rough global proxy, however,
instream uses may total 2,350 km3 a year, a conservative estimate that does not incorporate
all instream uses.

Combining this instream use figure with estimated global withdrawals puts the total at
6,780 km3 a year. that means humans currently are appropriating 54 percent of the acces-
sible freshwater runoff of the planet.

Global water demands continue to rise with increases in human population and con-
sumption. Increases in accessible runoff, however, can only be accomplished by construc-
tion of new dams or desalination of seawater. today, desalination accounts for less than
0.2 percent of global water use and, because of its high energy requirements, it is likely to
remain a minor part of global supply for the foreseeable future. Dams continue to bring
more water under human control, but the pace of construction has slowed. In developed
countries, many of the best sites have already been used. Rising economic, environmental,
and social costs—including habitat destruction, loss of biodiversity, and displacement of

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SECtIon 5.3 WAtER ShoRtAGES

human communities—are making fur-
ther dam construction increasingly dif-
ficult. About 260 new large dams now
come on line worldwide each year com-
pared with 1,000 a year between the
1950s and 1970s. Moreover, at least 180
dams in the United States were removed
in the past decade based on evalua-
tions of safety, environmental impact,
and obsolescence. the destruction of
the Edwards Dam on Maine’s Kennebec
River in 1999 marked the first time that
federal regulators ruled that the envi-
ronmental benefits of removing a dam
outweighed the economic benefits of
operating it.

As a result of these and other trends, accessible runoff is unlikely to increase by more than
5–10 percent over the next 30 years. During the same period, the earth’s population is pro-
jected to grow by approximately 35 percent. the demands on freshwater systems will continue
to grow throughout the coming century. [. . .]

Adapted from Jackson, R. B., et al. (2001). Water in a Changing World. Ecological Society of America, Issues in
Ecology, number 9. Retrieved from http://www.esa.org/esa/wp-content/uploads/2013/03/issue9 . Used
by permission.

Consider This
Read this short blog post by global water
expert Peter Gleick on the subject of
desalination (http://www.circleofblue.org
/waternews/2009/world/opinion-salt
– f r o m – w a t e r – m o n e y – f r o m – p o c k e t s / ) .
What are some of the major pros and cons
of this approach to increasing water sup-
ply? Is desalination a practical solution to
meeting global water demand in the fore-
seeable future?

Apply Your Knowledge
Start by taking this “Freshwater 101 Quiz” developed by national Geographic (http://environ
ment.nationalgeographic.com/environment/freshwater/freshwater-101-quiz/). how well
did you score? What questions/answers surprised you the most?

next, view two short films about the Colorado River (http://www.c-spanvideo.org/program
/ContestedW and http://www.smithsonianmag.com/multimedia/videos/Climate-Change
-and-the-Colorado-River.html). how has upstream use of Colorado River waters impacted
downstream communities and ecosystems? how do you think scientists might design a
research experiment to test the ecological impacts of large-scale water diversion projects?

5.3 Water Shortages
In this article by Don Hinrichsen of the Worldwatch Institute, we see that the overuse of freshwa-
ter supplies has a significant impact on wildlife, ecosystems, and human societies. For example,
diversion of freshwater for agriculture, industry, and residential uses leaves less water for other
species to drink. Use of rivers and other water bodies as dumping grounds for waste reduces
both the quality and quantity of water for other uses. And in some regions described in this read-
ing, lack of clean drinking water has already reached crisis proportions.

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http://www.esa.org/esa/wp-content/uploads/2013/03/issue9

http://www.circleofblue.org/waternews/2009/world/opinion-salt-from-water-money-from-pockets/

http://environment.nationalgeographic.com/environment/freshwater/freshwater-101-quiz/

http://www.c-spanvideo.org/program/ContestedW

http://www.smithsonianmag.com/multimedia/videos/Climate-Change-and-the-Colorado-River.html

SECtIon 5.3 WAtER ShoRtAGES

Specific areas of concern discussed in the following paper include the loss of wetlands, the
destruction of aquatic habitats, and the creation of pollution that ends up in various water
sources. Wetlands (areas of land with permanently or seasonally saturated soils) play a criti-
cally important role in maintaining freshwater supplies for two reasons—they slow moving
water down and improve storage, and they help to remove impurities and increase water qual-
ity. Wetland loss due to development and other factors thus impacts both water quantity and
quality. As was discussed in the last chapter, the loss of habitat is the major contributor to biodi-
versity loss, and this holds true for aquatic as well as terrestrial habitats. Large percentages of
the world’s fish, mussels, amphibians, and mollusks are endangered or have already been driven
to extinction due to modification of water flows or large-scale diversions of water. In addition to
habitat alteration and destruction, water pollution also takes a toll on biodiversity and supplies
of freshwater for human use. Up to a certain point, moving water can assimilate some human
waste and pollution. But the limit has been far exceeded and the consequences have been serious
impairment of surface waters.

Many regions of the world are already experiencing, or will soon experience, serious challenges
in meeting their water needs. China, reviewed in this article, increasingly has to grapple with the
consumptive/extractive versus instream/non-extractive tradeoffs discussed in section 5.1. The
Aral Sea Basin in Asia and Lake Chad in Africa offer cautionary examples of how bad the situa-
tion can get when water is mismanaged. Because increasing water supplies bumps up against
the limits of the hydrological cycle, perhaps the best way to meet the water needs of a growing
human population—while leaving enough water for other species—is to become much more
efficient in our use. Such a “blue revolution” in the efficiency of water use will be touched on
briefly in this article and in more detail in the next section.

Since this article was first written roughly 10 years ago, some of the problems it describes have
arguably gotten worse. For example, China’s Yangtze River dolphin is now believed to be “func-
tionally extinct,” and the fate of the Yangtze alligator is nearly as bleak. Likewise, the degrada-
tion and disappearance of the Aral Sea has continued apace, and that once great body of water
could disappear entirely by 2020. These are just a few of the reminders of why efforts to conserve
and protect water resources are so critical.

By Don Hinrichsen
on March 20, 2000, a group of monkeys, driven mad with thirst, clashed with desperate villag-
ers over drinking water in a small outpost in northern Kenya near the border with Sudan. the
Pan African news Agency reported that eight monkeys were killed and 10 villagers injured
in what was described as a “fierce two-hour melee.” the fight erupted when relief workers
arrived and began dispensing water from a tanker truck. locals claimed that a prolonged
drought had forced animals to roam out of their natural habitats to seek life-giving water in
human settlements. the monkeys were later identified as generally harmless vervets.

the world’s deepening freshwater crisis—currently affecting 2.3 billion people—has already
pitted farmers against city dwellers, industry against agriculture, water-rich state against
water-poor state, county against county, neighbor against neighbor. Inter-species rivalry over
water, such as the incident in northern Kenya, stands to become more commonplace in the
near future.

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“the water needs of wildlife are often the first to
be sacrificed and last to be considered,” says Karin
Krchnak, population and environment program
manager at the national Wildlife Federation (nWF)
in Washington, D.C. “We ignore the fact that working
to ensure healthy freshwater ecosystems for wild-
life would mean healthy waters for all.” As more and
more water is withdrawn from rivers, streams, lakes
and aquifers to feed thirsty fields and the voracious
needs of industry and escalating urban demands,
there is often little left over for aquatic ecosystems
and the wealth of plants and animals they support.

the mounting competition for freshwater resources
is undermining development prospects in many
areas of the world, while at the same time taking
an increasing toll on natural systems, according to
Krchnak, who co-authored an nWF report on pop-
ulation, wildlife, and water. In effect, humanity is
waging an undeclared water war with nature.

“there will be no winners in this war, only losers,”
warns Krchnak. By undermining the water needs of
wildlife we are not just undermining other species,
we are threatening the human prospect as well.

Pulling Apart the Pipes
Currently, humans expropriate 54 percent of all available freshwater from rivers, lakes,
streams, and shallow aquifers. During the 20th century water use increased at double the rate
of population growth: while the global population tripled, water use per capita increased by
six times. Projected levels of population growth in the next 25 years alone are expected to
increase the human take of available freshwater to 70 percent, according to water expert San-
dra Postel, Director of the Global Water Policy Project in Amherst, Massachusetts. And if per
capita water consumption continues to rise at its current rate, by 2025 that share could sig-
nificantly exceed 70 percent.

As a global average, most freshwater
withdrawals—69 percent—are used for
agriculture, while industry accounts for
23 percent and municipal use (drinking
water, bathing and cleaning, and water-
ing plants and grass) just 8 percent.

the past century of human develop-
ment—the spread of large-scale agri-
culture, the rapid growth of industrial
development, the construction of tens
of thousands of large dams, and the

Consider This
What are some reasons that might explain
why human water use increased at double
the rate of population growth during the
20th century? If humans already expropri-
ate 54 percent of all available freshwater,
how might further increases in population
affect global water supplies and availabil-
ity for other species?

. lubilub/iStock/Thinkstock

Millions of people around the world
are experiencing the effects of the
world’s deepening freshwater crisis,
often walking great distances to gather
drinking water for their families.

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SECtIon 5.3 WAtER ShoRtAGES

growing sprawl of cities—has profoundly altered the Earth’s hydrological cycle. Countless
rivers, streams, floodplains, and wetlands have been dammed, diverted, polluted, and filled.
these components of the hydrological cycle, which function as the Earth’s plumbing system,
are being disconnected and plundered, piece by piece. this fragmentation has been so exten-
sive that freshwater ecosystems are perhaps the most severely endangered today.

Wetland Loss
Consider the plight of wetlands—swamps, marshes, fens, bogs, estuaries, and tidal flats. Glob-
ally, the world has lost half of its wetlands, with most of the destruction having taken place
over the past half century. the loss of these productive ecosystems is doubly harmful to the
environment: wetlands not only store water and transport nutrients, but also act as natu-
ral filters, soaking up and diluting pollutants such as nitrogen and phosphorus from agricul-
tural runoff, heavy metals from mining and industrial spills, and raw sewage from human
settlements.

In some areas of Europe, such as Germany and France, 80 percent of all wetlands have been
destroyed. the United States has lost 50 percent of its wetlands since colonial times. More
than 100 million hectares of U.S. wetlands (247 million acres) have been filled, dredged, or
channeled—an area greater than the size of California, nevada, and oregon combined. In Cali-
fornia alone, more than 90 percent of wetlands have been tilled under, paved over, or other-
wise destroyed.

Biodiversity Loss
Destruction of habitat is the largest cause of biodiversity loss in almost every ecosystem, from
wetlands and estuaries to prairies and forests. But biologists have found that the brunt of cur-
rent plant and animal extinctions has fallen disproportionately on those species dependent
on freshwater and related habitats. one fifth of the world’s freshwater fish—2,000 of the
10,000 species identified so far—are endangered, vulnerable, or extinct. In north America,
the continent most studied, 67 percent of all mussels, 51 percent of crayfish, 40 percent of
amphibians, 37 percent of fish, and 75 percent of all freshwater mollusks are rare, imperiled,
or already gone.

the global decline in amphibian populations may be the aquatic equivalent of the canary in
the coal mine. Data are scarce for many species, but more than half of the amphibians studied
in Western Europe, north America, and South America are in a rapid decline.

Around the world, more than 1,000 bird species are close to extinction, and many of these
are particularly dependent on wetlands and other aquatic habitats. In Mexico’s Sonora Des-
ert, for instance, agriculture has siphoned off 97 percent of the region’s water resources,
reducing the migratory bird population by more than half, from 233,000 in 1970 to fewer
than 100,000 today.

Water Pollution
Pollution is also exacting a significant toll on freshwater and marine organisms. For instance,
scientists studying beluga whales swimming in the contaminated St. lawrence Seaway, which
connects the Atlantic ocean to north America’s Great lakes, found that the cetaceans have

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SECtIon 5.3 WAtER ShoRtAGES

dangerously high levels of PCBs in their blubber. In fact the contamination is so severe that
under Canadian law the whales actually qualify as toxic waste.

Waterways everywhere are used as sewers and waste receptacles. Exactly how much waste
ends up in freshwater systems and coastal waters is not known. however, the Un Food and
Agriculture organization (FAo) estimates that every year roughly 450 cubic kilometers
(99 million gallons) of wastewater (untreated or only partially treated) is discharged into
rivers, lakes, and coastal areas. to dilute and transport this amount of waste requires at least
6,000 cubic kilometers (1.32 billion gallons) of clean water. the FAo estimates that if current
trends continue, within 40 years the world’s entire stable river flow would be needed just to
dilute and transport humanity’s wastes.

Apply Your Knowledge
While you might have a good sense of your own direct water use through drinking, bath-
ing, and washing clothes and dishes, you might be surprised by how much water it takes
to produce many items that you consume on a regular basis. the concept of “embedded,”
“embodied,” or “virtual” water helps us to better understand the actual water requirements
of our consumption patterns. For this exercise, start by reviewing these two web pages from
national Geographic:

• the Global Water Footprint of Key Crops—http://environment.nationalgeographic
.com/environment/freshwater/global-water-footprint/

• the hidden Water We Use—http://environment.nationalgeographic.com
/environment/freshwater/embedded-water/

on the global water footprint page, click on some of the food items on the left side of the
graphic to see where the water comes from to grow the crops you consume regularly. on the
hidden water page, click on some of the food and other items in the graphic to learn more
about how much water it takes to produce that product. Compare a variety of products to see
how much water is involved in their production. lastly, try out this Water Footprint Calcula-
tor (http://environment.nationalgeographic.com/environment/freshwater/water-footprint
-calculator/) to estimate how much water you use and what aspects of your life are respon-
sible for most of your water consumption. Where is most of your water consumption taking
place? What steps are recommended to help you reduce your water footprint?

The Point of No Return?
the competition between people and wildlife for water is intensifying in many of the most
biodiverse regions of the world. of the 25 biodiversity hotspots designated by Conservation
International, 10 are located in water-short regions. these regions—including Mexico, Cen-
tral America, the Caribbean, the western United States, the Mediterranean Basin, southern
Africa, and southwestern China—are home to an extremely high number of endemic and
threatened species. Population pressures and overuse of resources, combined with critical
water shortages, threaten to push these diverse and vital ecosystems over the brink. In a
number of cases, the point of no return has already been reached.

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http://environment.nationalgeographic.com/environment/freshwater/global-water-footprint/

http://environment.nationalgeographic.com/environment/freshwater/embedded-water/

http://environment.nationalgeographic.com/environment/freshwater/water-footprint-calculator/

SECtIon 5.3 WAtER ShoRtAGES

China
China, home to 22 percent of the world’s population, is already experiencing serious water
shortages that threaten both people and wildlife. According to China’s former environment
minister, Qu Geping, China’s freshwater supplies are capable of sustainably supporting no
more than 650 million people—half its current population. to compensate for the tremen-
dous shortfall, China is draining its rivers dry and mining ancient aquifers that take thou-
sands of years to recharge.

As a result, the country has completely overwhelmed its freshwater ecosystems. Even in the
water-rich Yangtze River Basin, water demands from farms, industry, and a giant population
have polluted and degraded freshwater and riparian ecosystems. the Yangtze is one of the
longest rivers in Asia, winding 6,300 kilometers on its way to the Yellow Sea. this massive
watershed is home to around 400 million people, one-third of the total population of China.
But the population density is high, averaging 200 people per square kilometer. As the river,
sluggish with sediment and laced with agricultural, industrial, and municipal wastes, nears
its wide delta, population densities soar to over 350 people per square kilometer.

the effects of the country’s intense water demands, mostly for agriculture, can be seen in the
dry lake beds on the Gianghan Plain. In 1950 this ecologically rich area supported over 1,000
lakes. Within three decades, new dams and irrigation canals had siphoned off so much water
that only 300 lakes were left.

China’s water demands have taken a huge toll on the country’s wildlife. Studies carried out
in the Yangtze’s middle and lower reaches show that in natural lakes and wetlands still con-
nected to the river, the number of fish species averages 100. In lakes and wetlands cut off and
marooned from the river because of diversions and drainage, no more than 30 survive. Popu-
lations of three of the Yangtze’s largest and most productive fisheries—the silver, bighead,
and grass carp—have dropped by half since the 1950s.

Mammals and reptiles are in similar straits. the Yangtze’s shrinking and polluted waters are
home to the most endangered dolphin in the world—the Yangtze River dolphin, or Baiji. there
are only around 100 of these very rare freshwater dolphins left in the wild, but biologists pre-
dict they will be gone in a decade. And if any survive, their fate will be sealed when the mas-
sive three Gorges Dam is completed in 2013 [the dam was considered completed and fully
functional by 2012, but even before that the Yangtze River dolphin was declared “functionally
extinct” in 2006]. the dam is expected to decrease water flows downstream, exacerbate the
effects of pollution, and reduce the number of prey species that the dolphins eat. likewise,
the Yangtze’s Chinese alligators, which live mostly in a small stretch near the river’s swollen,
silt-laden mouth, are not expected to survive the next 10 years. In recent years, the alligator
population has dropped to between 800 and 1,000 [and is now believed to be below 150].

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The Aral Sea
the most striking example of human water demands destroying an ecosystem is the nearly
complete annihilation of the 64,500 square kilometer Aral Sea, located in Central Asia
between Kazakhstan and Uzbekistan. once the fourth largest inland sea in the world, it has
contracted by half its size and lost three-quarters of its volume since the 1960s, when its two
feeder rivers—the Amu Darya and the Syr Darya—were diverted to irrigate cotton fields and
rice paddies.

the water diversions have also deprived the region’s lakes and wetlands of their life source.
At the Aral Sea’s northern end in Kazakhstan, the lakes of the Syr Darya delta shrank from
about 500 square kilometers to 40 square kilometers between 1960 and 1980. By 1995, more
than 50 lakes in the Amu Darya delta had dried up and the surrounding wetlands had with-
ered from 550,000 hectares to less than 20,000 hectares.

the unique tugay forests—dense thickets of small shrubs, grasses, sedges and reeds—that
once covered 13,000 square kilometers around the fringes of the sea have been decimated. By
1999 less than 1,000 square kilometers of fragmented and isolated forest remained.

the habitat destruction has dramatically reduced the number of mammals that used to flour-
ish around the Aral Sea: of 173 species found in 1960, only 38 remained in 1990. though the
ruined deltas still attract waterfowl and other wetland species, the number of migrant and
nesting birds has declined from 500 species to fewer than 285 today.

Plant life has been hard hit by the increase in soil salinity, aridity, and heat. Forty years ago,
botanists had identified 1,200 species of flowering plants, including 29 endemic [native only
to that area] species. today, the endemics have vanished. the number of plant species that
can survive the increasingly harsh climate is a fraction of the original number.

Most experts agree that the sea itself may very well disappear entirely within two decades
[now predicted as possible by 2020]. But the region’s freshwater habitats and related com-
munities of plants and animals have already been consigned to oblivion.

. pkujiahe/iStock/Thinkstock Mark Carwardine/Photolibrary/Getty Images

China’s water demands have taken a huge toll on the country’s wildlife. The massive Three
Gorges Dam on the Yangtze River delivers electricity and agricultural water throughout China
but has left little for species such as the Yangtze River dolphin (Lipotes vexillifer), which was
declared “functionally extinct” in 2006.

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Lake Chad
lake Chad, too, has shrunk—to one-tenth of its former size. In 1960, with a surface area of
25,000 square kilometers, it was the second-largest lake in Africa. When last surveyed, it was
down to only 2,000 square kilometers. And here, too, massive water withdrawals from the
watershed to feed irrigated agriculture have reduced the amount of water flowing into the
lake to a trickle, especially during the dry season.

lake Chad is wedged between four nations: populous nigeria to the southwest, niger on the
northwest shore, Chad to the northeast, and Cameroon on a small section of the south shore.
nigeria has the largest population in Africa, with 130 million inhabitants. Population-growth
rates in these countries average 3 percent a year, enough to double human numbers in one
generation. And population growth rates in the regions around the lake are even higher than
the national averages. People gravitate to this area because the lake and its rivers are the only
sources of surface water for agricultural production in an otherwise dry and increasingly
desertified region.

Although water has been flowing into the lake from its rivers over the past decade, the lake is
still in serious ecological trouble. the lake’s fisheries have more or less collapsed from over-
exploitation and loss of aquatic habitats as its waters have been drained away. though some
40 commercially valuable species remain, their populations are too small to be harvested in
commercial quantities. only one species—the mudfish—remains in viable populations.

As the lake has withered, it has been unable to provide suitable habitat for a host of other spe-
cies. All large carnivores, such as lions and leopards, have been exterminated by hunting and
habitat loss. other large animals, such as rhinos and hippopotamuses, are found in greatly
reduced numbers in isolated, small populations. Bird life still thrives around the lake, but the
variety and numbers of breeding pairs have dropped significantly over the past 40 years.

A Blue Revolution
As these examples illustrate, the challenge for the world community is to launch a “blue revo-
lution” that will help governments and communities manage water resources on a more sus-
tainable basis for all users. “We not only have to regulate supplies of freshwater better, we
need to reduce the demand side of the equation,” says Swedish hydrologist Malin Falkenmark,
a senior scientist with Sweden’s natural Science Research Council. “We need to ask how much
water is available and how best can we use it, not how much do we need and where do we get
it.” Increasingly, where we get it from is at the expense of aquatic ecosystems.

If blindly meeting demand precipitated, in large measure, the world’s current water crisis,
reducing demand and matching supplies with end uses will help get us back on track to a
more equitable water future for everyone. While serious water initiatives were launched
in the wake of the World Summit on Sustainable Development held in Johannesburg, South
Africa, not one of them addressed the water needs of ecosystems.

there is an important lesson here: just as animals cannot thrive when disconnected from
their habitats, neither can humanity live disconnected from the water cycle and the natural
systems that have evolved to maintain it. It is not a matter of “either or” says nWF’s Krch-
nak. “We have no real choices here. Either we as a species live within the limits of the water

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cycle and utilize it rationally, or we could
end up in constant competition with each
other and with nature over remaining
supplies. Ultimately, if nature loses, we
lose.”

By allowing natural systems to die, we
may be threatening our own future. After
all, there is a growing consensus that nat-
ural ecosystems have immense, almost
incalculable value. Robert Costanza, a

resource economist at the University of Maryland, has estimated the global value of fresh-
water wetlands, including related riverine and lake systems, at close to $5 trillion a year.
this figure is based on their value as flood regulators, waste treatment plants, and wildlife
habitats, as well as for fisheries production and recreation.

the nightmarish scenarios envisioned for a water-starved not too distant future should be
enough to compel action at all levels. the water needs of people and wildlife are inextricably
bound together. Unfortunately, it will probably take more incidents like the one in northern
Kenya before we learn to share water resources, balancing the needs of nature with the needs
of humanity.

Adapted from Hinrichsen, D. (2003, January/February). A Human Thirst. World Watch. Retrieved from http://www
.worldwatch.org/system/files/EP161A . Used by permission.

5.4 Water Conservation and Management
There is a growing consensus among water experts that the “supply-side” approaches to water
management that dominated the 20th century—building dams, diversion systems, and other
infrastructure to increase supply—will need to give way to a new approach in the 21st century.
This new approach is more focused on the “demand side” and emphasizes water conservation
and making the most of the water supplies we already have. In the following article by Elizabeth
Royte of national Geographic Magazine, we see that some places, such as Albuquerque, New
Mexico, have already embraced a demand-side approach with great success. Further progress
in conserving water and reducing demand, especially in the agricultural sector, will depend as
much or more on appropriate policy and economic incentives as on technological breakthroughs.

The situation that faced Albuquerque was similar to the bank account analogy used in the intro-
duction to section 5.1. The city was withdrawing water from its underground aquifer faster than
it was being replenished by rainfall and snowmelt, and so it was on track to run out of water
from that source. Demand-side, or “soft-path” approaches have reduced Albuquerque’s residen-
tial per capita water use from 140 to 80 gallons per day, but it is still using water faster than it
can be replenished.

Consider This
Define the concept of a “blue revolution”
and speculate about reasons the topic
of ecosystem destruction—rather than
human consumption—has been left out of
summit talks and water initiatives.

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SECtIon 5.4 WAtER ConSERVAtIon AnD MAnAGEMEnt

In order to bring water use under control, attention has now shifted to agriculture, the largest
consumer of water in many regions. In addition to helping farmers adopt water-saving technol-
ogies, such as precision irrigation, there is also a recognition that water policy needs to change,
especially with regards to pricing this resource. Currently, the price of water for agriculture is
heavily subsidized throughout the U.S. southwest, and so farmers have relatively little incen-
tive to conserve. Unless greater progress can be made in bringing water demand under control
and improving the efficiency of water use in agriculture and other sectors, we may be forced to
resort to desalination (removal of salt and other minerals from water) and/or greater reuse of
wastewater. Both of these options can be expensive and energy-intensive, but in some regions
they may represent the only option available to meeting water demand. For more information
on some of the water conservation techniques and approaches described in this article, see the
Working toward Solutions section at the end of this chapter. Likewise, the Additional Resources
section at the end of the chapter features other case studies of communities and groups around
the world finding ways to prevent water pollution and make more efficient use of this resource.

By Elizabeth Royte
living in the high desert of northern new Mexico, louise Pape bathes three times a week,
military style: wet body, turn off water, soap up, rinse, get out. She reuses her drinking cup for
days without washing it, and she saves her dishwater for plants and unheated shower water
to flush the toilet. While most Americans use around a hundred gallons of water a day, Pape
uses just about ten.

“I conserve water because I feel the planet is dying, and I don’t want to be part of the prob-
lem,” she says.

You don’t have to be as committed an
environmentalist as Pape, who edits a
climate-change news service, to real-
ize that the days of cheap and abundant
water are drawing to an end. But the
planet is a long way from dying of thirst.
“It’s inevitable that we’ll solve our water
problems,” says Peter Gleick, president of
the Pacific Institute, a nonpartisan envi-
ronmental think tank. “the trick is how
much pain we can avoid on that path to
where we want to be.”

As Gleick sees it, we’ve got two ways to go forward. hard-path solutions focus almost
exclusively on ways to develop new supplies of water, such as supersize dams, aqueducts,
and pipelines that deliver water over huge distances. Gleick leans toward the soft path:
a comprehensive approach that includes conservation and efficiency, community-scale
infrastructure, protection of aquatic ecosystems, management at the level of watersheds
instead of political boundaries, and smart economics.

Consider This
Describe the primary differences between
a supply-side or hard-path approach to
water management and a demand-side or
soft-path approach.

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The Case of Albuquerque
Until the mid-1980s, the city of Albuquerque, some 60 miles southwest of Pape’s home in Santa
Fe, was blissfully unaware that it needed to follow any path at all. hydrogeologists believed the
city sat atop an underground reservoir “as big as lake Superior,” says Katherine Yuhas, conser-
vation director of the Albuquerque Bernalillo County Water Utility Authority. the culture was
geared toward greenery: Realtors attracted potential home buyers from moist regions with
landscaping as verdant as Vermont; building codes required lawns. But then studies revealed
startling news: Albuquerque’s aquifer was nowhere near the size it once appeared to be and
was being pumped out faster than rainfall and snowmelt could replenish it.

Duly alarmed, the city shifted into high gear. It revised its water-use codes, paid homeowners
to take classes on reducing outdoor watering, and offered rebates to anyone who installed
low-flow fixtures or a drip-irrigation system or removed a lawn. today Albuquerque is a striv-
ing example of soft-path parsimony. Across the sprawling city, a growing number of residents
and building owners funnel rainwater into barrels and underground cisterns. Almost every-
one in town uses low-flow toilets and showerheads.

these efforts have shrunk Albuquerque’s domestic per capita water use from 140 gallons a
day to around 80. the city “anticipates another 50 years of water, economically and sustain-
ably supplied, even with a growing population,” says Yuhas. After that there’s the option
to desalinate brackish water nearby and new technologies such as dual plumbing: one set
of pipes to deliver highly treated potable water and another to recycle less treated water
for flushing toilets, watering lawns, and other nonpotable uses. Albuquerque already uses
wastewater—from treatment plants and from industry—to irrigate golf courses and parks.
other municipalities have gone a step further and collect wastewater—yes, from toilets—
filter and disinfect it to the nth degree, then pump it back into the local aquifer for drinking.
there are similar schemes worldwide: Beijing reportedly aims to reuse 100 percent of its
wastewater by 2013. [While there is no evidence that Beijing has come close to achieving this
ambitious goal, they are a global leader in municipal reuse systems.]

Industry, too, is adapting to less certain water supplies. Frito-lay will soon recycle almost all
its water at its plant in Casa Grande, Arizona; Gatorade and Coca-Cola remove the dust and
carton lint from beverage containers using air instead of water; and Google recycles its own
water to cool its giant data centers.

Water Demand for Agriculture
this is all reassuring—until you remember that irrigated agriculture accounts for 70 percent
of the fresh water used by humans. Given this outsize proportion, it seems obvious that farm-
ers have the greatest potential to conserve water.

Standing on the banks of a trickling ditch, Don Bustos—sunbaked and thickly bearded—
demonstrates how he irrigates 130,000 dollars’ worth of produce on 3.5 acres north of
Santa Fe. “I lift this board”—he points to a plank that forms a gate in the ditch—”and I shove
in a stick to hold it up.” Gravity does the rest.

For 400 years farmers in the arid Southwest have relied on such acequias—networks of
community-operated ditches—to irrigate their crops. the acequia diverts water from a main
stream, then further apportions the flow through sluiceways into smaller streams and onto

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fields. “Without the acequia, there would be no farm,” Bustos says. he’s also built a water tank
with drip-irrigation hoses that feed some of the acequia water directly to the plant roots—
and cut his water use by two-thirds as a consequence.

Elsewhere, forward-thinking farmers have replaced flood irrigation with micro-sprinkler
systems, laser leveled their fields, and installed soil-moisture monitors to better time irriga-
tion. In California, says the Pacific Institute, such improvements could potentially conserve

roughly five million acre-feet of water a
year, enough to meet the household needs
of 37 million people. Unfortunately, most
farmers lack the incentive to install effi-
cient but expensive irrigation systems:
Government subsidies keep farm water
cheap. But experts agree that more real-
istic water pricing and improved water
management will significantly cut agri-
cultural water use. one way or another,
the developed world will get the water
it needs, if not the water it wants. We
can find new supplies—by desalinating
water, recycling water, capturing and fil-
tering storm water from paved surfaces,
and redistributing water rights among
agriculture, industry, and cities. Cheaply
and quickly we can slash demand—with
conservation and efficiency measures,
with higher rates for water wasters, and
with better management policies.

Hope for the Future?
What about the rest of the world? In places lacerated by poverty, the problem is often a lack
of infrastructure—wells, pipes, pollution controls, and systems for disinfecting water. though
politically challenging to execute, the solutions are fairly straightforward: investment in
appropriately scaled technology, better governance, community involvement, proper water
pricing, and training water users to maintain their systems. In regions facing scarcity because
of overpumped aquifers, better management and efficiency will stretch the last drops. Farm-
ers in southern India, for example, save fuel in addition to water when they switch from flood
to drip irrigation; other communities landscape their hillsides to retain rainwater and replen-
ish aquifers.

Still, the time is coming when some farmers—the largest water users and the lowest
ratepayers—may find themselves rethinking what, or if, they should plant in the first place.
In the parched Murray-Darling Basin of Australia, farmers are already packing up and mov-
ing out.

It is hardly the first time that water scarcity has created environmental refugees. A thou-
sand years ago, less than 120 miles from modern-day Santa Fe, the inhabitants of Chaco Can-
yon built rock-lined ditches, headgates, and dams to manage runoff from their enormous

. Maxvis/iStock/Thinkstock

Agricultural advances in water efficiency, such
as drip irrigation, have helped to conserve water
in the face of increasing stress on the world’s
freshwater supplies.

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watershed. then, starting around A.D. 1130, a prolonged drought set in. Water scarcity may
not have been the only cause, but within a few decades, Chaco Canyon had been abandoned.
We hardly need reminding that nature can be unforgiving: We learn to live within her increas-
ingly unpredictable means, we move elsewhere, or we perish.

Adapted from Royte, E. (2010, April). The Last Drop. national Geographic Magazine, 217(4), 172–177. Retrieved
from http://ngm.nationalgeographic.com/print/2010/04/last-drop/royte-text. Elizabeth Royte/National Geo-
graphic Creative. Used by permission.

Apply Your Knowledge
Consider issues of water supply and demand in your own community. Start by determining
where your water actually originates. Does it come from a municipal source or your own well?
Is it from surface water (such as reservoirs) or groundwater deposits? how far does it travel
to get to your home or apartment? Most municipal water authorities provide a lot of this infor-
mation on the Web. next, what do you think are the major users of water in your commu-
nity? Is it agriculture? Industry? Golf courses and residential watering? how much is water
an “issue” in your community? Is water expensive and in short supply? lastly, draw up a basic
management plan for what your community might do, like Albuquerque, to reduce its water
use. how would you attempt to implement this plan? Who would you focus your efforts on and
how might you gain their cooperation?

5.5 Case History—Water, Conflict, and Cooperation
in the Middle East

One region of the world facing significant water challenges is the Middle East, and in that region
the case of the Jordan River is of particular interest. The waters of the Jordan are shared by
Israel, Jordan, Syria, and the Palestinian territories. Given the history of conflict in the region and
increased demands for freshwater from residents, it’s not surprising that the Jordan River has
come under significant stress. In this article by Gidon Bromberg, the Israeli Director of Friends of
the Earth Middle East, we learn of the challenges facing the Jordan River and a unique approach
to restoring it that combines environmental efforts with initiatives to build trust among usually
distrustful factions.

The Jordan River, just like the Colorado River (and other once-great rivers), barely reaches the
sea anymore. Consumptive/extractive uses are so great that the river has been reduced in some
months to barely a trickle. Complicating the management and restoration of the Jordan is the
political situation in the region, with the different countries involved essentially diverting water
for their own use as well as attempting to prevent its use by others.

Against this difficult backdrop an effort is underway to help restore the Jordan. What’s most
interesting about this effort is that it combines an environmental objective with initiatives to
help build trust and promote peace among groups that have traditionally been at odds. Israeli,
Jordanian, and Palestinian communities are working together to conserve water and educate
themselves about the importance of the river. In addition, the groups involved are working at
the national level to improve water policy and reduce large-scale diversions of water from the

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SECtIon 5.5 Case History—Water, ConfliCt, and Cooperation in tHe Middle east

river. Such an approach—referred to as environmental peacemaking—is based on the recogni-
tion that dependence on the environment and the services it provides can be a unifying point.
After all, regardless of what nationality or religious group you belong to, everyone needs access
to freshwater.

While this case study offers some hope of the possibility of shared solutions to addressing the
water crisis, it may not be enough. Climate change is already worsening water shortages in
some regions of the world, and population growth combined with water pollution and overuse is
further exacerbating this problem. As such, serious conflicts over water supply and distribution
are likely to grow in the decades ahead. In this sense, environmental issues and national security
concerns become clearly connected, and efforts at water conservation and pollution prevention
take on enormous political importance.

By Gidon Bromberg
the River Jordan has flowed freely for thousands
of years, its name immortalized in the hebrew
Bible and its lush upper reaches once known as the
gates to the Garden of Eden. this summer [2008],
however, large sections of this storied river were
reduced to a trickle, the water so low that grass
fires spread freely across the Jordan Valley between
Israel and Jordan. Steadily drained over the past
half century to quench the thirst and grow the crops
of the people of Israel, Jordan, Syria, and the Pales-
tinian territories, the Jordan River has been dealt a
deathblow recently by a severe drought and by yet
another tributary dam, this one on the Jordanian-
Syrian border.

In recent years, all that saved much of the lower Jor-
dan from becoming a desiccated channel has been
the agricultural runoff, raw human sewage, diverted
saline spring water, and contaminated wastes from
fish farms that have been pumped into it. But now
even that effluent barely restores a flow to the Jor-
dan, the river where Jesus Christ was baptized and
which has long been a vital stopover on the migra-
tory pathway of tens of millions of birds en route
between Europe and Africa.

the degradation highlights the failure of the gov-
ernments of Israel, Jordan, and Syria to take serious
steps to rescue a 205-mile river that has deep mean-
ing for Christianity, Judaism, and Islam. Although these governments have paid lip service to
bringing the Jordan back to life, they have in fact encouraged water withdrawals—mainly for
irrigated agriculture—that have led to its near-disappearance. this ecological catastrophe
has been overshadowed by decades of war and regional conflict. Indeed, for the past 60 years,
much of the river—a fenced and mined border zone between Israel and Jordan—has been off-
limits, enabling its draining to take place out of sight and out of mind.

age fotostock/SuperStock

The Jordan River has been a source
of multiple conflicts between Israel
and its neighbors, including the 1967
“Six-Day War” (one element of dispute
involved diversion of the Jordan River)
and the 2006 Lebanon War (Israel had
been angered by Lebanon’s diversion
of Wazzani River water to border
villages).

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the governments of the region have blamed the conflict for their lack of action, but as the
citizens’ group I help run—EcoPeace/Friends of the Earth Middle East—has shown, inter-
national cooperation to resuscitate the Jordan is possible. Working with local communities,
my Jordanian, Palestinian, and Israeli colleagues are striving to restore water to the river.
the goal of our group—the region’s only multinational organization—is to become a catalyst
for comprehensive water policy reform. We are aided by an unexpected phenomenon: In a
region where people often feel helpless after years of turmoil, our efforts at environmental
peacemaking offer an opportunity for constructive action, dialogue, and cooperation.

Exploitation of the Jordan River
the story of the depletion of the Jordan is hardly unique. Around the world, human activity
has pulled so much water out of great rivers—the Indus on the Indian subcontinent, the Yel-
low in China, the Rio Grande along the U.S.–Mexico border—that they now either disappear
before reaching the sea or contain long sections that seasonally run dry. the underlying rea-
son is always the same: We view rivers not as valuable in themselves, supplying vital “ecosys-
tem services” to people, fish, animals, and plants, but rather as merely tools for humans and
economic development.

that was certainly the case in the early days of the formation of Israel, when the dream of
nation building was to “make the desert bloom.” In the 1950s, that dream was married to
advanced engineering as Israel’s national Water Carrier diverted about a third of the original
flow of the Jordan to tel Aviv and the farms of the negev Desert. Subsequent Israeli water
withdrawals, coupled with scores of dam and canal projects on tributaries in Syria and Jor-
dan, claimed the rest of the river’s water. For ages, the Sea of Galilee has fed the longest stretch
of the river, the lower Jordan, but today not a drop of fresh water flows out of the sea into the
river. the largest tributary to the lower Jordan, the Yarmouk River, has similarly had all its
waters diverted by Syria and Jordan. As these insults to the Jordan have accumulated, water
disputes in this rain-starved region have grown ever more contentious, with unequal water
allocations—coupled with violence and occupation—becoming a powerful human rights
issue and an additional source of animosity.

Just as the Jordan is hitting bottom, another troubling development is unfolding. the World
Bank has selected two consulting firms to study the feasibility of pumping water from the Red
Sea to the Dead Sea, the terminus of the Jordan River, via a massive and staggeringly expen-
sive pipeline. Because of the Jordan’s catastrophic reduction in flows—from a historic level
of 1.3 billion cubic meters annually to only about 70,000 cubic meters now—the surface area
of the Dead Sea has shrunk by a third in the past 50 years and the level of the sea, the world’s
lowest point, is dropping by a meter a year. Rather than tackling the root problem destroying
the river and draining the Dead Sea—which would require restoring flows to the Jordan—the
World Bank, supported by Jordan, Israel, and the Palestinian Authority, is throwing its weight
behind a huge public works project that could easily cost $5 billion to $10 billion and will
likely have damaging ecological consequences.

A Different Approach
the so-called Red-Dead project would be rendered obsolete if nations bordering the Jordan
would begin putting water back into the river. But with regional governments taking little
action, Friends of the Earth Middle East has stepped in to push for measures that will gradu-
ally return water to the Jordan. our approach is two-pronged: the first is a program called

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Good Water neighbors, in which we work with nine river communities—four Jordanian,
three Israeli, and two Palestinian, all located on opposite banks—to conserve water and edu-
cate people about the value of the Jordan and its wetlands. the second, and more challenging,
task is to persuade national leaders to make the tough choices that will revitalize the Jordan:
charging more for water, removing large subsidies to agricultural water users, and adopting
large-scale conservation programs.

our group has made progress because we are a grassroots, multi-national effort with Jor-
danian, Israeli and Palestinian staff members working inside their own communities while
simultaneously reaching out to nationalities across the river. one of our core beliefs is that the
region will never achieve a lasting peace until we begin talking directly to each other. tackling
a crucial environmental challenge that affects us all is a good start.

In each community, a staff person from Friends of the Earth Middle East, who is a local resi-
dent, has pushed an ambitious agenda with adults and youth. the teams have begun water
conservation and rainwater harvesting programs in schools and other buildings. they have
publicized the plight of the river and have gathered 15,000 signatures on petitions that were
presented to elected officials. they have persuaded Israeli, Palestinian, and Jordanian mayors
from both banks to sign memoranda of understanding, committing themselves to help bring
the river back to life. Recently, members of the different communities have been visiting each
other to see their towns and water conservation programs. last year, officials in Jordan and
Israel agreed to create a Peace Park at the confluence of the Jordan and Yarmouk rivers that
will include a bird sanctuary, eco-lodges, a visitor’s center, and nature and heritage trails. And
given the river’s importance in religious history, we’re enlisting representatives of the Mus-
lim, Christian, and Jewish faiths in the campaign. Rehabilitating the Jordan has become much
more than an environmental crusade; it’s now an international project backed by school chil-
dren, community leaders, and scientists.

these are small steps, but set against the backdrop of widespread hostility—and the absence
of similar regional initiatives—our programs take on greater meaning. What is needed now is
action from the Israeli and Jordanian governments, hopefully to be joined in the near future
by Syria. they could start by creating an international commission to manage the Jordan,

similar to the commissions that gov-
ern north America’s Great lakes and
Europe’s Rhine River. Regional govern-
ments and international donor states,
including the U.S., also need to take a hard
look at the proposed Red Sea–Dead Sea
canal, a potential boondoggle that could
cause major problems, including mixing
the marine water of the Red Sea with the
fresh water of the Dead Sea, which could
change the composition of the Dead Sea
and cause algal blooms. the wiser, and
far cheaper, alternative is to revive the
Dead Sea by restoring its main source of
water—the Jordan River.

Consider This
Given the scale and magnitude of the prob-
lems facing the Jordan River, are the efforts
of Friends of the Earth Middle East going
to have any significant impact? Are there
other things this group and others should
be doing than those described in this
reading?

ben85927_05_c05.indd 213 1/27/14 9:09 AM

SUMMARY & RESoURCES

For decades now, conflict and human arrogance have been responsible for the demise of the
Jordan. Cooperation in search of peace and sustainability is the only hope to restore it to
health.

Adapted from Bromberg, G. (2008). Will the Jordan River Keep on Flowing? Yale Environment 360. Copyright
© 2008 Gidon Bromberg. Retrieved from http://e360.yale.edu/content/print.msp?id=2064. Reprinted by
permission of the author.

Summary & Resources

Chapter Summary
of all the water on this blue planet of ours, less than 1 percent is accessible and fresh enough
to be used. What is remarkable is that, due to the hydrological cycle, this tiny sliver of the
overall water resource can be constantly recycled and purified and reused provided we utilize
this resource sustainably. As was suggested earlier in this chapter, we can think of this avail-
able, renewable water supply as a bank account that’s replenished on a regular basis. If we
choose to live within our means and withdraw water at a rate that’s equal to or less than the
rate of replenishment, we will not go broke.

While helpful, the bank account analogy oversimplifies the situation a little and requires us to
consider a few other points. First, we can think of the renewable freshwater supply as a single
account, but in reality this resource is distributed in different locations throughout the world
and in vastly different quantities. Some remote and sparsely populated regions of the world
receive massive amounts of freshwater in the form of rain and snow, while other densely
populated regions receive very little. In other words, some regions have very little cash com-
ing in but a lot of expenses to meet while others have a lot of cash but few expenses.

Second, we need to budget some of the funds in our freshwater account for other species
and for critical ecosystem functions. Were humans to appropriate all of the world’s available
freshwater supplies, we would trigger an ecological collapse that would ripple through our
own economy and society. As it stands, we currently appropriate over half of the global fresh-
water supply, and this already has detrimental impacts on other species.

third, some regions of the world find themselves with a type of ecological inheritance in the
form of groundwater aquifers created over thousands of years ago. Because these ancient
aquifers are not being replenished, “fossil water” is nonrenewable; nevertheless, they have
still been tapped and overpumped in many regions.

For most of the 20th century, our approach to water management has been to find ways to
divert more funds into the freshwater account. We have dammed rivers, created large-scale
diversion projects, overpumped from aquifers, and essentially replumbed large sections of
the global water cycle. With population still growing and global climate change already wors-
ening water issues in some areas, there is now recognition that for all of these efforts there is
still only so much fresh water to work with—and that in many regions withdrawals from the
account exceed deposits. As a result, greater attention is being paid to demand-side or soft-
path approaches that focus on getting our water expenditures under control. If more funds
cannot be added to our global water account, then we’ll need to learn to make use of what is

ben85927_05_c05.indd 214 1/27/14 9:09 AM

http://e360.yale.edu/content/print.msp?id=2064

SUMMARY & RESoURCES

available far more efficiently. Just as some regions of the world have relied on nonrenewable
“fossil water” to meet some or all of their water needs, we currently rely on nonrenewable
“fossil fuels” to meet the bulk of our energy needs. the next chapter will examine the ways in
which we use these fossil fuels and other nonrenewable minerals and the implications of our
dependence on them.

Working Toward Solutions
Because the water cycle does not recognize or respect national or political boundaries, man-
aging water as a shared global resource presents a serious challenge. According to journalist
Fred Pearce (2012), more than 40 percent of the world’s population lives in river basins that
cross international borders, and many of the world’s great rivers flow through multiple coun-
tries. Yet there are few successful cases of water sharing or management agreements between
nations. Instead, there seem to be more and more cases of upstream countries threatening
to dam or otherwise alter river flows in ways that could damage or disrupt water supplies
to downstream communities. A United nations treaty designed to address this problem, the
1997 Convention on the non-navigable Uses of International Watercourses, does not yet have
enough signatories to come into force.

In addition to the legal, political, and diplomatic efforts to improve global water management,
there are many organizations working on the ground at the local level to address issues of
water shortages, water pollution, and sanitation. Among the most prominent of these organi-
zations are:

• Water.org—http://water.org/
• World Water Council—http://www.worldwatercouncil.org/
• Global Water—http://www.globalwater.org/
• Global Water Partnership—http://www.gwp.org/
• Un Water—http://www.unwater.org/index.html
• International Rivers—http://www.internationalrivers.org/

Many of these organizations work directly with communities in water-scarce regions of Africa,
Asia, and latin America to help them secure safe and reliable water supplies. they gener-
ally favor solutions that are low-cost, locally managed, and sustainable, rather than trying to
impose expensive, top-down, and highly technical approaches. the importance of these efforts
is illustrated in this short, four-minute video from the Circle of Blue network (http://www
.circleofblue.org/waternews/2009/world/video-no-reason/).

At the national level, water quality in the United Stateshas benefited tremendously since pas-
sage of the Clean Water Act in 1972. the Clean Water Act sets standards and limits on the
amount of pollutants that can be discharged into rivers, lakes, and other waterways. Many in
the environmental community would argue that no other single piece of environmental legis-
lation has had as big of an impact on the quality of our lives and health than the Clean Water
Act. You can learn more about the Clean Water Act and its importance in maintaining our
water quality here (http://www2.epa.gov/laws-regulations/summary-clean-water-act) and
here (http://www.rivernetwork.org/introduction-cwa-course).

(continued)

ben85927_05_c05.indd 215 1/27/14 9:09 AM

http://water.org/

http://www.worldwatercouncil.org/

http://www.globalwater.org/

http://www.gwp.org/

http://www.unwater.org/index.html

Home

http://www.circleofblue.org/waternews/2009/world/video-no-reason/

http://www2.epa.gov/laws-regulations/summary-clean-water-act

http://www.rivernetwork.org/introduction-cwa-course

SUMMARY & RESoURCES

Working Toward Solutions (continued)

While water quality issues are being effectively addressed through the national Clean Water
Act, water quantity and management issues still make for heated controversies in some areas
of the United States. nowhere is this more so than in the U.S. southwest where limited water
supplies and rising populations have set up conflicts between competing water users. A num-
ber of organizations in the United States are working to settle these conflicts and improve
water management practices, including:

• American Rivers—http://www.amrivers.org/
• River network—http://www.rivernetwork.org/
• the nature Conservancy—http://www.nature.org/
• the pacific institute—http://www.pacinst.org/
• Growing Blue—http://growingblue.com/

there are also many organizations working at the local level to address issues of water quality
and management, including an entire network of groups known as Riverkeepers or Water-
keepers (http://www.waterkeeper.org/). likewise, many local and municipal water authori-
ties are active in taking steps to protect their water supplies and ensure an adequate supply
of clean water for their customers. one of the best examples of this is the efforts of new York
City. Most of the city’s drinking water originates from reservoirs located over 100 miles away
in the Catskill region of upstate new York. When agriculture and land development prac-
tices upstate began to degrade water quality in those reservoirs, the city was faced with the
prospect of spending billions of dollars on water treatment systems to ensure water quality.
Instead, working with local, state, and federal government agencies as well as environmental
and community groups, the city opted to spend significantly less money on “source protection”
efforts. these efforts are designed to protect water quality in the first place, rather than build-
ing expensive water treatment systems after water quality has already been degraded. You can
learn more about new York City’s efforts and source protection programs in other parts of the
country here:

• http://water.epa.gov/infrastructure/drinkingwater/sourcewater/protection
/casestudies/index.cfm

• http://water.epa.gov/infrastructure/drinkingwater/sourcewater/protection
/casestudies/upload/Source-Water-Case-Study-nY-nY-City-7-Upstate-Counties

• http://www.nyc.gov/html/dep/html/drinking_water/index.shtml
• http://growingblue.com/case-studies/freshwater-for-the-big-apple/

At an individual level there are a number of things you can do to reduce your own water foot-
print, conserve water, and become more educated about local, national, and global water issues.
Start by reviewing this list of 10 things you should know about water (http://www.circleof
blue.org/waternews/2009/world/infographic-ten-things-you-should-know-about-water/).

next, review these sites that provide information on the most common ways water is wasted
and techniques for conserving this critical resource:

• http://www.scientificamerican.com/article.cfm?id=top-10-water-wasters
• http://www.scientificamerican.com/article.cfm?id=fresh-water-conservation
• http://environment.nationalgeographic.com/environment/freshwater/top-ten/

(continued)

ben85927_05_c05.indd 216 1/27/14 9:09 AM

http://www.amrivers.org/

Home

http://www.nature.org/

http://www.pacinst.org/

http://growingblue.com/

Home

http://water.epa.gov/infrastructure/drinkingwater/sourcewater/protection/casestudies/index.cfm

http://water.epa.gov/infrastructure/drinkingwater/sourcewater/protection/casestudies/upload/Source-Water-Case-Study-NY-NY-City-7-Upstate-Counties

http://www.nyc.gov/html/dep/html/drinking_water/index.shtml

http://growingblue.com/case-studies/freshwater-for-the-big-apple/

http://www.circleofblue.org/waternews/2009/world/infographic-ten-things-you-should-know-about-water/

http://www.scientificamerican.com/article.cfm?id=top-10-water-wasters

http://www.scientificamerican.com/article.cfm?id=fresh-water-conservation

http://environment.nationalgeographic.com/environment/freshwater/top-ten/

SUMMARY & RESoURCES

Post-test

1. A scientist who studies the movement, storage, and distribution of water is called a
hydrolysist.
a. true
b. False
2. Which of the following is not a major category of human water use?
a. Industry
b. Agriculture
c. transportation
d. Residential

3. During the 20th century, the world population tripled, while water use per person
increased by six times.

a. true
b. False

4. the “supply-side” approach to water conservation emphasizes water-saving tech-
niques and reducing demand.

a. true
b. False

5. the Friends of the Earth Middle East plan for restoring the Jordan River represents a
“hard-path” approach to water management

a. true
b. False
Working Toward Solutions (continued)

lastly, you can find out more about water and how to get involved in solving water problems
in your own community or around the world by visiting these pages:

• http://www.waterfootprint.org/?page=files/home
• http://environment.nationalgeographic.com/environment/freshwater/
• http://environment.nationalgeographic.com/environment/freshwater/resources/
• http://www.scientificamerican.com/article.cfm?id=get-involved-in-fresh-water

-conservation
• http://www.alexandracousteau.org/
• http://www.circleofblue.org/waternews/
• http://www.internationalrivers.org/world-rivers-review/world-rivers-review

-%E2%80%93-december-2012-focus-on-citizen-science

ben85927_05_c05.indd 217 1/27/14 9:09 AM

Front Page

http://environment.nationalgeographic.com/environment/freshwater/

http://environment.nationalgeographic.com/environment/freshwater/resources/

http://www.scientificamerican.com/article.cfm?id=get-involved-in-fresh-water-conservation

http://www.alexandracousteau.org/

Circle of Blue

http://www.internationalrivers.org/world-rivers-review/world-rivers-review-%E2%80%93-december-2012-focus-on-citizen-science

SUMMARY & RESoURCES

6. What might explain a scenario in which the Earth’s mean temperature was below
freezing and surface water was scarce?

a. Excess atmospheric water was present.
b. Greenhouse gases were absent.
c. heat was being trapped in the atmosphere.
d. Solar energy had evaporated all the methane.

7. Approximately how many people on the planet currently lack access to adequate and
safe water supplies?

a. over 1 billion
b. over 100 million
c. Under 50 million
d. Under 10 million

8. the United States has lost 50 percent of its wetlands since colonial times.
a. true
b. False

9. Which of the following is not an example of a soft-path solution?
a. Community-operated ditches
b. Micro-sprinkler systems
c. new cross-country water pipelines
d. Protecting a pond’s ecosystem

10. the group Friends of the Earth Middle East plans to restore the depleted Jordan
River using all of the following measures EXCEPt

a. paying large subsidies to agricultural water users.
b. training river communities to conserve water.
c. persuading national leaders to adopt conservation programs.
d. educating people about the value of the Jordan and its wetlands.

Answers
1. b. False. the answer can be found in Section 5.1.
2. c. transportation. the answer can be found in Section 5.2.
3. a. true. the answer can be found in Section 5.3.
4. b. False. the answer can be found in Section 5.4.
5. b. False. the answer can be found in Section 5.5.
6. b. Greenhouse gases were absent. the answer can be found in Section 5.1.
7. a. over 1 billion. the answer can be found in Section 5.2.
8. a. true. the answer can be found in Section 5.3.
9. c. new cross-country water pipelines. the answer can be found in Section 5.4.
10. a. paying large subsidies to agricultural water users. the answer can be found in Section 5.5.

ben85927_05_c05.indd 218 1/27/14 9:09 AM

SUMMARY & RESoURCES

Key Ideas

• the hydrological cycle or water cycle is the continuous movement of water on,
above, and below the surface of the Earth. While roughly 80 percent of the Earth’s
surface is covered by water, only a tiny fraction of this water is fresh enough and
available for human use.

• Because freshwater resources are distributed unevenly across the Earth’s surface,
millions of people worldwide lack access to adequate water supplies. Between five
and ten million people, mostly children, die from water-related diseases each year.

• Groundwater, or water found below the Earth’s surface, is a critical source of fresh-
water for billions of people. however, not all groundwater deposits are renewable or
recharged from surface infiltration, and over-pumping and pollution of groundwater
supplies is a growing problem worldwide.

• human water use is typically broken into extractive or non-extractive categories.
Extractive uses include water consumed directly for agricultural, commercial/
industrial, or residential purposes. non-extractive or instream uses include water
for navigation, fisheries, recreation, dilution of pollutants, and protection of
biodiversity.

• humans currently expropriate or use over half of all available freshwater from riv-
ers, lakes, streams, and aquifers, leaving less than half for other species and ecosys-
tem functions. Roughly two-thirds of this consumption is used for agriculture.

• overuse of water, pollution, and destruction of wetland ecosystems is already put-
ting water supply at risk in places like China, the Aral Sea Basin, lake Chad in Africa,
and the American southwest.

• Supply-side or hard-path approaches to water management involve developing
new supplies of freshwater through dams, pipelines, and other projects. In contrast,
demand-side or soft-path approaches involve making more efficient use of and con-
serving the water supplies we already have.

• the Jordan River is one of many rivers around the world that suffers from overuse,
pollution, and habitat alteration. Because it is located in a region of limited water
supplies and political instability, its management is a potential source of conflict
between nations.

Critical thinking and Discussion Questions

1. In essence, all of the water that is currently on the planet is all that there ever was
and all there ever will be. Since water is “recycled” through the hydrological or
global water cycle, it would seem that we could never “run out” of water or encoun-
ter freshwater shortages. Based on what you have learned in this chapter, how can
you explain the concern that so many water experts have over future supplies of
fresh water? What specific forms of water are these experts most worried about, and
what human activities and actions are the greatest source of their concern?

2. the construction of dams is one way to capture and store water for future use, a fea-
ture that is especially important in parts of the world where rainfall is irregular and
highly seasonal. however, the construction of dams can be expensive, and dams can
alter aquatic ecosystems and displace human populations. Suppose you were asked
to lead a research team charged with completing an environmental and social impact
assessment of a proposed dam project on a river in your community. What kinds
of information would you want to start compiling in order to complete this assess-
ment? What sorts of costs and benefits would be the focus of your analysis? What
kinds of groups might you encounter who would tend to be in favor of or opposed to
this project?

ben85927_05_c05.indd 219 1/27/14 9:09 AM

SUMMARY & RESoURCES

3. What is the connection between wetland loss and water supply? Why are wetlands
important in maintaining both water quantity and water quality?

4. the examples of water management in China, the Aral Sea, and the lake Chad region
all tell a similar story—overuse and over-exploitation of water supplies for short-
term economic development followed by potentially catastrophic changes to aquatic
ecosystems on which people depend. Are there other alternatives to this type of
development that might avoid these catastrophic outcomes? or are we doomed to
only learn after we have made mistakes?

5. Considering the high percentage of water use (70 percent) attributed to agriculture,
what solutions need to be implemented for farmers to better conserve water? What
possible ideas do the Albuquerque example and the Jordan study offer about govern-
ment responsibility and participation in this effort?

6. to what extent do you agree with the approach taken by Friends of the Earth Middle
East to use people’s common dependence on freshwater supplies as a way to bridge
their differences over religion or politics? Could this approach be used in other
regions or with other resources?

Key terms

aquifer An underground bed or layer of
porous rock, sediment, or soil that yields
water.

desalination the removal of salt and other
minerals from seawater to make it suitable for
human consumption and/or industrial use.

evapotranspiration the process by which
water is transferred from land to the atmo-
sphere through evaporation, or the process
of water converting to water vapor, from the
soil and other surfaces and by transpiration,
or the process of giving off water vapor, from
the leaves of plants.

hydrological cycle the continuous move-
ment of water on, above, and below the
surface of the Earth; also known as the
water cycle.

semi-arid region A region characterized by
low annual rainfall that is subject to frequent
and prolonged droughts.

water table the uppermost level of an
aquifer, below which the ground is saturated
with water.

Additional Resources
A basic understanding of the hydrological or water cycle is essential to understanding the
need for careful management of water resources and the threats posed by pollution, habitat
change, and over-pumping of groundwater. the following sites provide a clear graphic of the
water cycle and animations of how this cycle actually operates:

• http://ga.water.usgs.gov/edu/watercycle.html
• http://www.youtube.com/watch?v=0_c0ZzZfC8c
• http://www.teachersdomain.org/asset/ess05_int_hydrocycle/

ben85927_05_c05.indd 220 1/27/14 9:09 AM

http://ga.water.usgs.gov/edu/watercycle.html

http://www.teachersdomain.org/asset/ess05_int_hydrocycle/

SUMMARY & RESoURCES

Further reading on how the water cycle actually works can be found here:

• http://www.eoearth.org/article/hydrologic_cycle
• http://earthobservatory.nasa.gov/Features/Water/page1.php
• http://earthobservatory.nasa.gov/Features/Water/page2.php

A scientific article from the journal Nature on the important role that rivers play in moving
sediment can be found here:

• http://www.nature.com/scitable/knowledge/library/rivers-and-streams-water
-and-26405398

lastly, an excellent overview of some basic information on water resources—including the
water cycle, the global distribution of freshwater and groundwater, water demand, water
depletion, pollution, and water laws and treaties—can be found here:

• http://www.learner.org/courses/envsci/unit/text.php?unit=8&secnum=0

there are a number of excellent sources with information on water availability and demand
around the world. the first is a detailed graphic showing levels of global water use by region
and areas of significant concern:

• http://www.nature.com/news/water-under-pressure-1.10216

the Pacific Institute is a leader in studying and reporting on global water issues and chal-
lenges. It publishes the biannual report The World’s Water; you can read sample chapters
from this document and see some of the tables, figures, and data it uses here:

• http://worldwater.org/
• http://www.worldwater.org/data.html

Information on public water supply systems in the United States and what it takes to actually
provide water resources and sanitation to a community can be found here:

• http://ga.water.usgs.gov/edu/wups.html
• http://ga.water.usgs.gov/edu/dryville.html

A series of case studies on water use and water challenges from places in the United States
and around the world can be found here:

• http://growingblue.com/case-studies/

two sources on how groundwater and surface water interact and can be viewed as one source
can be found at these sites. the first is a more basic explanation of the topic while the second
is more detailed and scientific in its coverage:

• http://www.water.ca.gov/groundwater/groundwater_basics/gw_sw_interaction.cfm
• http://pubs.usgs.gov/circ/circ1139/

ben85927_05_c05.indd 221 1/27/14 9:09 AM

http://www.eoearth.org/article/Hydrologic_cycle

http://earthobservatory.nasa.gov/Features/Water/page1.php

http://earthobservatory.nasa.gov/Features/Water/page2.php

http://www.nature.com/scitable/knowledge/library/rivers-and-streams-water-and-26405398

http://www.learner.org/courses/envsci/unit/text.php?unit=8&secNum=0

http://www.nature.com/news/water-under-pressure-1.10216

Home

http://www.worldwater.org/data.html

http://ga.water.usgs.gov/edu/wups.html

http://ga.water.usgs.gov/edu/dryville.html

http://growingblue.com/case-studies/

http://www.water.ca.gov/groundwater/groundwater_basics/gw_sw_interaction.cfm

http://pubs.usgs.gov/circ/circ1139/

SUMMARY & RESoURCES

lastly, an interesting article on how a global water crisis can easily translate into a global
food crisis can be found here:

• http://e360.yale.edu/feature/water_scarcity_the_real_food_crisis/1825/

Unfortunately, there are so many problems with water shortages and water pollution around
the world that there are multiple sources of information and detailed reports on specific case
studies. the following stories all report on challenges with water pollution or other forms
of water mismanagement. the first of these articles makes the argument that China’s very
economic success is actually threatened more than anything else by water shortages and
mismanagement:

• http://e360.yale.edu/feature/growing_shortages_of_water_threaten_chinas
_development/2298/

• http://e360.yale.edu/feature/on_chinas_beleaguered_yangtze_a_push_to_save
_surviving_species/2311/

• http://e360.yale.edu/feature/melting_glaciers_may_worsen_china_water_woes
_tarim_river/2556/

• http://www.nature.com/news/demand-for-water-outstrips-supply-1.11143
• http://e360.yale.edu/feature/africas_flourishing_niger_delta_threatened_by_libya

_water_plan/2366/

Scientific American has a special report and accompanying graphics on a global freshwater
crisis:

• http://www.scientificamerican.com/report.cfm?id=water
• http://www.scientificamerican.com/article.cfm?id=freshwater-crisis-current

-situation

this short film from Yale Environment 360 tells the story of Chinese villagers who are stand-
ing up to polluting factories in order to protect their water supply:

• http://e360.yale.edu/feature/the_warriors_of_qiugang_a_chinese_village_fights
_back/2358/

this tED talk by engineer Michael Pritchard explains how his lifesaver filter or water
purification bottle could make the difference between life and death in disaster areas with
limited access to fresh water:

• http://youtu.be/rXepkIWPhFQ

lastly, these two articles discuss the link between suburban sprawl and water shortages in
the United States as well as the concept of “peak water” and the challenges we face in meeting
global water demand in the decades ahead:

• http://www.smartgrowthamerica.org/research/paving-our-way-to-water
-shortages

• http://www.siwi.org/documents/Resources/Water_Front_Articles/2008/Peak
_Water

ben85927_05_c05.indd 222 1/27/14 9:09 AM

http://e360.yale.edu/feature/water_scarcity_the_real_food_crisis/1825/

http://e360.yale.edu/feature/growing_shortages_of_water_threaten_chinas_development/2298/

http://e360.yale.edu/feature/on_chinas_beleaguered_yangtze_a_push_to_save_surviving_species/2311/

http://e360.yale.edu/feature/melting_glaciers_may_worsen_china_water_woes_tarim_river/2556/

http://www.nature.com/news/demand-for-water-outstrips-supply-1.11143

http://e360.yale.edu/feature/africas_flourishing_niger_delta_threatened_by_libya_water_plan/2366/

http://www.scientificamerican.com/report.cfm?id=water

http://www.scientificamerican.com/article.cfm?id=freshwater-crisis-current-situation

http://e360.yale.edu/feature/the_warriors_of_qiugang_a_chinese_village_fights_back/2358/

http://www.smartgrowthamerica.org/research/paving-our-way-to-water-shortages

http://www.siwi.org/documents/Resources/Water_Front_Articles/2008/Peak_Water

SUMMARY & RESoURCES

When it comes to water conservation and management, there is a clear distinction to be
made between large-scale approaches known as hard-path solutions and smaller-scale, local
approaches known as soft-path solutions. the following sources spell out some of these dif-
ferences and make the case for a greater reliance on soft-path solutions going forward:

• http://e360.yale.edu/feature/beyond_big_dams_turning_to_grass_roots_solutions
_on_water/2571/

• http://www.rivernetwork.org/blog/7/2009/06/10/soft-path-approach

Many economists argue that one of the reasons water resources are mismanaged is because
there are few incentives for sustainable management. the first link below is a tED talk by
economist Rob harmon on market mechanisms for water management, while the second link
is to an article in Forbes magazine on the economics of water management:

• http://youtu.be/YeJhVtJKJU8
• http://www.forbes.com/sites/amywestervelt/2012/10/23/how-scarce-does

-water-need-to-get-before-its-valuable/

Another tED talk on the effectiveness of ancient and traditional water management systems
in India as well as a series of short videos on water and food by the Blue legacy project can
be found here:

• http://youtu.be/eJCtAXb_BWs
• http://www.alexandracousteau.org/food

the U.S. Environmental Protection Agency Water Sense program provides a wealth of infor-
mation on how to conserve water and increase water use efficiency:

• http://epa.gov/watersense/pubs/supply.html

lastly, the Worldmapper website provides an interesting perspective on many issues by cre-
ating world maps that distort the shape and size of a country based on a particular variable.
these two maps show how much higher rates of water use are in the wealthier countries of
the world as well as how serious water quality problems are in the poorer countries of the
world:

• http://www.worldmapper.org/display.php?selected=104
• http://www.worldmapper.org/display.php?selected=186

A good place to start any research on the role of water in international conflict is oregon State
University’s Program in Water Conflict Management and transformation:

• http://www.transboundarywaters.orst.edu/index.html

the Pacific Institute provides a fascinating set of resources on the link between water and
conflict, including an historical timeline of water conflicts, a list of current conflicts, and a
world map of places where control over water supplies has been or could be a source of vio-
lent conflict:

• http://www.worldwater.org/conflict.html

ben85927_05_c05.indd 223 1/27/14 9:09 AM

http://e360.yale.edu/feature/beyond_big_dams_turning_to_grass_roots_solutions_on_water/2571/

http://www.rivernetwork.org/blog/7/2009/06/10/soft-path-approach

http://www.forbes.com/sites/amywestervelt/2012/10/23/how-scarce-does-water-need-to-get-before-its-valuable/

http://www.alexandracousteau.org/food

http://epa.gov/watersense/pubs/supply.html

http://www.worldmapper.org/display.php?selected=104

http://www.worldmapper.org/display.php?selected=186

http://www.transboundarywaters.orst.edu/index.html

http://www.worldwater.org/conflict.html

SUMMARY & RESoURCES

the following articles all report on brewing conflicts between nations over water supplies
and how U.S. intelligence officials are increasingly worried about water as a trigger for inter-
national conflicts in the future:

• http://e360.yale.edu/feature/does_egypt_own_the_nile_a_battle_over_precious
_water/2297/

• http://www.globalpolicy.org/the-dark-side-of-natural-resources-st/water-in
-conflict.html

• http://www.time.com/time/world/article/0,8599,2111601,00.html
• http://rt.com/news/water-conflict-terrorism-rivers-239/

lastly, the Circle of Blue program has two basic sources of information that powerfully com-
municate the challenges of global water supply and management. the first is a list of ten
things you should know about water, and the second is a short, four-minute film on why we
all should care about global water issues:

• http://www.circleofblue.org/waternews/2009/world/infographic-ten-things
-you-should-know-about-water/

• http://www.circleofblue.org/waternews/2009/world/video-no-reason/

Finally, it’s important to understand a little about how wastewater from our homes, schools,
and businesses is treated so that it can be returned to a condition suitable for re-use. the fact
that billions of people in the poorest developing countries do not have access to wastewater
treatment facilities further complicates water supply issues in those places.

• http://water.worldbank.org/shw-resource-guide/infrastructure/menu-technical
-options/wastewater-treatment

• http://www.cleanwaterservices.org/AboutUs/WastewaterAndStormwater
/treatmentProcess.aspx

• http://water.me.vccs.edu/courses/env110/lesson12.htm
• http://www.nyc.gov/html/dep/html/wastewater/wwsystem-process.shtml
• http://vimeo.com/1973831

ben85927_05_c05.indd 224 1/27/14 9:09 AM

http://e360.yale.edu/feature/does_egypt_own_the_nile_a_battle_over_precious_water/2297/

http://www.globalpolicy.org/the-dark-side-of-natural-resources-st/water-in-conflict.html

http://www.time.com/time/world/article/0,8599,2111601,00.html

http://rt.com/news/water-conflict-terrorism-rivers-239/

http://www.circleofblue.org/waternews/2009/world/infographic-ten-things-you-should-know-about-water/

http://www.circleofblue.org/waternews/2009/world/video-no-reason/

http://water.worldbank.org/shw-resource-guide/infrastructure/menu-technical-options/wastewater-treatment

http://www.cleanwaterservices.org/AboutUs/WastewaterAndStormwater/TreatmentProcess.aspx

http://water.me.vccs.edu/courses/env110/lesson12.htm

http://www.nyc.gov/html/dep/html/wastewater/wwsystem-process.shtml

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