PART IV
SUSTAINING NATURAL RESOURCES
CHAPTER 14
FOOD AND SOIL RESOURCES
THINKING
Goals
See bulleted list of questions on p. 274 of text.
Objectives
1.
List four major types of agriculture. Compare the energy sources, environmental impacts, yields, and
sustainability of traditional and industrial agriculture.
2.
Evaluate the green revolution. What were its successes? Its failures? Summarize the benefits and problems
of livestock production over the history of agriculture.
3.
Define interplanting, and explain its advantages. List and briefly describe four types of interplanting
commonly used by traditional farmers.
4.
Summarize the state of global food production. Define malnutrition, undernutrition, and overnutrition.
Indicate how many people on Earth suffer from these problems and where these problems are most likely to
occur. List six steps proposed by UNICEF to deal with malnutrition and undernutrition. Describe a strategy
to reduce overnutrition.
5.
Discuss the use of genetic engineering techniques to improve the human food supply.
6.
Describe the problems of soil erosion and desertification. Describe both world and U.S. situations, and
explain why most people are unaware of this problem.
7.
Describe the problems of salinization and waterlogging of soils and how they can be controlled.
8.
Define soil conservation. List nine ways to approach the problem of soil erosion. Be sure to distinguish
between conventional-tillage and conservation-tillage farming. Describe a plan to maintain soil fertility. Be
sure to distinguish between organic and inorganic fertilizers.
9.
Summarize environmental impacts from agriculture.
10. Summarize food distribution problems. Describe the possibilities of increasing world food production by
increasing crop yields, cultivating more land, and using unconventional foods and perennial crops.
11. Discuss problems associated with the production of livestock on rangeland.
12. Describe trends in the world fish catch since 1950. Assess the potential for increasing the annual fish catch
and use of aquaculture. Distinguish between fish farming and fish ranching.
13. Assess the pros and cons of agricultural subsidies and international food relief. Describe strategies that you
feel would be most sustainable.
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14. Define sustainable agriculture. Summarize how the United States could move toward creating a more
sustainable agricultural system.
Key Terms (Terms are listed in the same font style as they appear in the text.)
polyculture (p. 273)
perennial polyculture (p. 273)
modern monoculture (p. 273)
eastern grama grass (p. 273)
mammoth wildrye (p. 273)
Illinois bundleflower (p. 273)
Maximillian sunflower (p. 273)
croplands (p. 274)
rangelands (p. 274)
oceanic fisheries (p. 274)
net primary productivity (p. 274)
annuals (p. 274)
industrialized agriculture (p. 275)
high-input agriculture (p. 275)
plantation agriculture (p. 275)
cash crops (p. 275)
feedlots (p. 275)
traditional agriculture (p. 275)
traditional subsistence agriculture (p. 275)
traditional intensive agriculture (p. 275)
green revolution (p. 276)
multiple cropping (p. 276)
first green revolution (p. 276)
second green revolution (p. 276)
agribusiness (p. 276)
interplanting (p. 278)
polyvarietal cultivation (p. 278)
intercropping (p. 278)
agroforestry (p. 278)
alley cropping (p. 278)
polyculture (p. 278)
tassas (p. 279)
land degradation (p. 279)
soil erosion (p. 279)
flowing water (p. 279)
wind (p. 279)
desertification (p. 281)
salinization (p. 283)
waterlogging (p. 283)
soil conservation (p. 284)
conventional-tillage farming (p. 284)
conservation-tillage farming (p. 284)
minimum-tillage farming (p. 284)
no-till farming (p. 284)
terracing (p. 284)
contour farming (p. 284)
strip cropping (p. 284)
cover crops (p. 284)
windbreaks (p. 285)
120
shelterbelts (p. 285)
land classification (p. 285)
organic fertilizer (p. 285)
commercial inorganic fertilizer (p. 285)
animal manure (p. 285)
green manure (p. 286)
compost (p. 286)
spores of mushrooms (p. 286)
crop rotation (p. 286)
macronutrients (p. 287)
micronutrients (p. 287)
chronic undernutrition (p. 287)
malnutrition (p. 287)
marasmus (p. 287)
kwashiorkor (p. 287)
iron (p. 288)
anemia (p. 288)
iodine (p. 288)
overnutrition (p. 288)
overweight (p. 288)
obese (p. 288)
crossbreeding (p. 291)
artificial selection (p. 291)
third green revolution (p. 291)
gene revolution (p. 291)
age of genetic engineering (p. 291)
advanced tissue culture (p. 291)
transgenomics (p. 290)
genetically modified food (GMF) (p. 291)
winged bean (p. 293)
microlivestock (p. 293)
marginal land (p. 293)
rangeland (p. 294)
pastures (p. 294)
overgrazing (p. 295)
riparian zones (p. 296)
fisheries (p. 297)
aquaculture (p. 297)
trawler fishing (p. 297)
bycatch (p. 298)
purse-seine fishing (p. 298)
longlining (p. 298)
drift-net fishing (p. 298)
overfishing (p. 298)
commercial extinction (p. 298)
Aquaculture (p. 300)
fish-farming (p. 300)
fish-ranching (p. 300)
Spirulina (p. 301)
Section One: Chapter 14
sustainable agriculture (p. 302)
low-input agriculture (p. 302)
organic farming (p. 302)
agroecology (p. 302)
Outline
14-1 How Is Food Produced?
Food on the planet is produced by croplands, rangelands, and ocean fisheries.
A. Croplands produce 77% of the world’s food.
B. Rangelands produce meat, which is about 16% of the world’s food.
C. Oceanic fisheries supply 7% of the world’s food.
D. All three systems have increased their food yields since 1950.
1. Technological advances have increased food production or harvesting.
2. More sophisticated farming techniques have been developed.
3. There has been expanded use of inorganic chemical fertilizers, irrigation, and pesticides, and highyield crops have been developed.
4. Intense farming methods, such as densely populated feedlots and enclosed breeding/growing pens,
and aquaculture ponds or ocean cages have been implemented.
E. Food to feed the planet must be produced in ever-increasing quantities.
1. Genetic engineering brings some promise to this endeavor.
2. The planet’s net primary productivity is being degraded by human activities.
3. The world’s poverty must be reduced so that people can obtain enough food to sustain them.
F. The foods that sustain the world are wheat, rice, and corn. They must be replanted each year.
1. Industrialized/high-input agriculture produces large quantities of single crop or livestock animals.
a. This uses much energy, water, fertilizers, and pesticides.
b. It is practiced on 25% of cropland, mostly in developed countries.
c. Plantation agriculture is industrialized agriculture, primarily in tropical developing countries.
Monoculture crops—bananas, coffee, soybeans, and sugarcane—are cash crops.
d. Another example of industrialized agriculture is feedlots, which support rapid growth of
fattened animals for meat.
2. Traditional agriculture provides about 20% of the food supply and is practiced by 42% of the
world’s people.
a. Traditional subsistence agriculture typically supports a single farm family’s survival.
b. Traditional intensive agriculture strives to feed not only the farmer’s family, but also to
produce additional food to sell as income. By using fertilizer, irrigating, etc., a higher yield is
sought.
14-2 Producing Food by Green Revolution and Traditional Techniques
A. The green revolution has increased yields in food production per unit of existing cropland. The
following steps describe this revolution.
1. Key grain crops of plant monocultures are bred or enhanced to produce high-yield varieties.
2. High-yields are sustained by using large amounts of fertilizer, water, and pesticides.
3. The number of crops grown per year is increased through multiple cropping.
B. There have been two green revolutions.
1. The first revolution occurred in developing countries between 1950 and 1970.
2. The second revolution has occurred since 1967 in developing countries with enough rain and/or
irrigation capability.
a. Fast-growing dwarf varieties of rice and wheat, especially for tropical and subtropical
climates, have been introduced.
b. Use of pesticides, water, and fertilizers as well as food yields have increased.
c. Several crops can be planted during one year, increasing food yields further.
3. Such revolutions use machinery and fossil fuel to plant and harvest; high-input green revolution
agriculture uses 8% of the world’s oil output.
C. The U.S. agricultural system produces 17% of the world’s grain but affects the environment more than
any other industry.
1. Agriculture is bigger than the automotive, steel, and housing industries combined in total annual
sales.
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2.
3.
Agriculture has doubled crop yield of wheat, corn and soybeans, using no more land, since 1940.
Large agribusinesses (huge corporate/family-owned farms) control three-fourths of U.S. food
production. Labor and resource costs, with the exception of pesticides, have decreased since 1950.
4. This development was possible because of cheap energy. But the efficiency of U.S. agriculture is
far below that of traditional subsistence farming or traditional intensive farming.
5. Considering energy used to grow, store, process, package, transport, refrigerate, and cook all plant
and animal food, about 10 units of nonrenewable fossil fuel is needed to put 1 unit of food energy
on the table.
D. Growing techniques in traditional agriculture are used to make yields more productive.
1. Interplanting grows several crops on the same plot of land.
a. Polyvarietal cultivation plants several varieties of the same crop on a plot.
b. Intercropping grows two or more different crops on the same plot at the same time.
c. Agroforestry/alley cropping grows crops and trees together.
d. Polyculture plants many different crops, which mature at various times, together.
1) Polyculture requires less fertilizer and water because of the root systems are at different
levels.
2) The soil is protected from wind and water erosion because crops are growing year-round.
3) Multiple habitats support natural predators of crop-eating insects, so less insecticide is
needed.
4) There are fewer weeds and less need for herbicides.
5) With several crops, bad weather will not destroy every one of them.
2. Low-input polyculture produces higher crop yields than high-input monoculture.
3. Use of tassas, small pits filled with manure, has tripled yields on at least 100,000 hectares.
14-3 Soil Erosion and Degradation
Soil erosion and degradation affect crop yield and farming success.
A. Preserving the world’s topsoil is of great importance in feeding the world’s masses.
1. Land degradation occurs when the future ability of the land to support crops, livestock, or wild
species is decreased.
2. Water, wind, and people cause soil erosion; soil components are moved from one place to another.
3. Depletion of plant nutrients in topsoil, through farming, logging, construction, overgrazing, and
burning vegetation, leads to loss of soil fertility.
4. Eroded soil becomes sediment in surface waters where it pollutes water, kills fish, and clogs
irrigation ditches, channels, reservoirs, and lakes.
5. Soil is a renewable resource unless eroded faster than it can form.
B. A 1992 joint UN and World Resources Institute report estimated that topsoil is eroding faster than it is
replenished on 38% of the world’s cropland. Worldwide erosion causes $375 billion per year.
1. Soil erosion in the U.S. is being slowed through planting crops without disturbing the soil and
government-sponsored soil conservation programs.
2. The Dust Bowl of the 1930s resulted in Congress passing the Soil Erosion Act in 1935 and
established the Soil Conservation Service (a part of the USDA).
3. Desertification occurs when production falls by 10% or more though a combination of natural
causes (drought) and human activities. It may be moderate, severe, or very severe; only in extreme
cases does it lead to a desert.
4. Prolonged droughts can’t be controlled, but the consequences can be reduced by reducing
overgrazing, deforestation, and destructive forms of planting, irrigation, and mining.
5. Restoration of these areas includes planting trees and grasses to anchor soil and hold water.
C. Loss of crop productivity can result from repeated irrigation, which produces salt buildup and water
logging of plant crops.
1. Forty percent of the world’s food is produced on twenty percent of the cropland that is irrigated.
2. Salts left behind when irrigation water is not absorbed into the soil can be left in the topsoil. This
is called salinization.
3. Salinization has reduced yields on 20% of the world’s cropland.
4. Waterlogging occurs when saline water (from irrigation) envelops the deep roots of plants. This
saline water accumulates underground and raises the water table.
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14-4 Soil Conservation
Soil conservation seeks ways to reduce soil erosion and restore soil fertility.
A. To reduce soil erosion, farmers must eliminate plowing and tilling and keep the soil covered with
vegetation.
1. Conventional-tillage farming means plowing in the fall and leaving the soil bare all winter,
making it vulnerable to wind and erosion.
2. Conservation-tillage farming disturbs the soil as little as possible while planting.
3. Minimum-tillage farming allows the soil to rest over the winter. The subsurface soil is broken up
and loosened but the topsoil is not turned.
4. No-till farming uses special machines to inject seeds, fertilizers, and herbicides into thin slits in
the unplowed soil and, then, cover the slits.
5. About 45% of U.S. farmers used conservation tillage in 2003. The USDA estimates that using it
on 80% of cropland would reduce soil erosion by 50% or more.
B. Additional methods to reduce soil erosion include:
1. Terracing converts the land into a series of broad, nearly level terraces that run across the contour
of the land. This method holds water for crops and reduces runoff.
2. Contour farming plows and plants crops in rows across the slope of the land, not up and down.
Each row acts as a small dam.
3. Strip cropping plants alternating strips of a row crop (corn/cotton) with another crop that
completely covers the soil (grass/legume). Runoff is caught by the cover crop.
4. Plant cover crops like rye or alfalfa after harvest.
5. Leave crop residues on the land after harvest.
6. Alley cropping/agroforestry plants several crops together in strips/alleys between trees or shrubs,
which may provide fruit or fuelwood.
a. The shade of the trees/shrubs reduces evaporation and helps retain soil moisture.
b. Fruit, fuelwood, and trimming can be used as mulch.
7. Windbreaks or shelterbelts of trees reduce wind erosion, help retain soil moisture, provide
fuelwood, and support bird and insect habitats.
C. Soil fertility can be maintained best through soil conservation. The next best thing is to restore some of
the nutrients by the use of fertilizer.
1. Organic fertilizer can be used to restore lost plant nutrients.
a. Animal manure improves soil structure, adds nitrogen, and stimulates soil bacteria and fungi.
b. The U.S. Department of Agriculture researchers are evaluating the value of burnt chicken
wastes that are rich in phosphorus as an organic fertilizer.
c. Green manure plows freshly cut or growing green vegetation into the soil to increase organic
matter and humus.
d. Microorganisms in the soil break down organic matter in leaves, food wastes, paper, and
wood to form compost.
2. Crop rotation plants different crops to replenish the soil, especially if a previous crop has depleted
the soil of certain nutrients.
3. Inorganic fertilizers, used with organic fertilizers, can restore soil fertility.
a. Commercial inorganic fertilizers contain nitrogen, phosphorus, and potassium.
b. There are advantages and disadvantages to the use of inorganic fertilizers (Figure 14-15).
14-5 Food Production, Nutrition, and Environmental Effects
Food production increased significantly from 1950 to 1985 when production leveled off.
A. Per capita food production has begun to decline, particularly in Africa since 1970, in the former Soviet
Union since 1990, and in China since 1998.
B. More than enough food is produced to meet everyone’s basic needs, but one in six people go hungry
because of uneven food distribution.
C. Poverty and inequality are the root causes of hunger and malnutrition. War, corruption, tariffs, and
subsidies are other factors at work here.
D. People need fairly large amounts of macronutrients (protein, carbohydrates, and fats) and smaller
amounts of micronutrients (vitamins such as A, C, and E) and minerals (iron, iodine, and calcium).
1. Chronic undernutrition is suffered by those who can’t grow or buy enough food. Children in this
group may have stunted growth, mental retardation, and be susceptible to infectious diseases.
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2.
Malnutrition results from insufficient protein and other key nutrients.
a. Marasmus and kwashiorkor are two of the most common diseases of malnutrition.
b. Marasmus is a wasting, especially when a diet is low in both calories and protein. If the child
is treated in time the effects of malnutrition can be reversed.
c. Kwashiorkor is severe protein deficiency of infants and children ages 1–3. If caught in time,
the effects can generally be reversed.
d. About one in six people in developing countries are chronically undernourished with an estimate
of 5.5 million people dying prematurely from poverty, undernutrition, malnutrition, and
increased susceptibility to normally non-fatal diseases. About 80% are children under age 5.
3. UNICEF studies show that one-half to two-thirds of these deaths could be prevented by:
a. immunizing children against childhood diseases,
b. encouraging breast feeding,
c. preventing dehydration from diarrhea by giving a mixture of sugar and salt in a glass of water,
d. giving children vitamin A capsules two times per year to prevent blindness,
e. providing family planning services for spacing children, and
f. increasing education for women, emphasizing nutrition, water sterilization, and childcare.
E. WHO states that about one in three people suffer from a deficiency of one or more of the following:
vitamin A, iron, and iodine.
1. Blindness due to vitamin A deficiency occurs in 250,000 children under 6 each year, and up to
80% die within a year.
2. Golden rice has a gene spliced into it to enrich beta-carotene, but poorly nourished people can’t
convert beta-carotene into vitamin A.
3. Iron is needed to prevent anemia, and iodine is needed for proper thyroid function and to prevent
brain damage or formation of a goiter.
F. Overnutrition is when food intake exceeds energy needs and results in body fat. Too little exercise, too
many calories, or both cause overnutrition.
G. Both overnutrition and undernutrition in people lead to similar health problems: lower life expectancy,
greater susceptibility to disease and illness, and lower productivity and life quality.
1. After smoking, overnutrition is the second leading cause of preventable death.
2. In developed countries, one of every seven adults suffers from overnutrition.
H. The most harmful environmental impact caused by human activity is modern agriculture.
1. Modern agriculture is responsible for most groundwater depletion.
2. Modern agriculture is responsible for 70% of water pollution.
3. Agriculture is contributing to reduced food production and contributing to land degradation.
4. These environmental factors will limit food production: soil erosion, salt build-up and
waterlogging, water deficits and droughts, and loss of wild species that provide genetic resources.
I. Population growth, economic growth, lack of resources, and harmful environmental effects of food
production may limit crop production in China.
1. Grain production has fallen since 1998.
2. Incomes have risen and with it, increased meat consumption.
3. Indications are that China may soon exceed its carrying capacity if it hasn’t already.
4. Other experts say that China can begin exporting grain again by 2020 and has more potential
cropland than previously thought.
14-6 Increasing Crop Production
Crossbreeding, which mixes the genes of similar types of organisms, and genetic engineering, which mixes
genes of different organisms, can be used to increase yields of crops.
A. Crossbreeding is a 15+-year process. The varieties are useful only for a few years; then pests and
diseases reduce the effectiveness of the new varieties.
B. Genetic engineering, which splices a gene from one species into the DNA of another species, is
creating improved strains of crops and livestock animals.
1. This process can take half as much time than traditional methods to develop a new crop.
2. It cuts costs.
3. It allows for all kinds of potential product development.
4. More than two-thirds of food products on the U.S. shelves contain ingredients made from
genetically engineered crops.
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5.
C.
D.
E.
F.
G.
H.
I.
J.
K.
Scientists are experimenting with cell cultures to produce a variety of food and medical products
in fermentation tanks or bioreactors.
GMF (genetically modified food) has generated much controversy and fear.
1. GMF may possibly solve the world’s food problems.
2. Advantages and disadvantages of GMF are listed in Figure 14-19.
The unknowns of genetically modified crops on human health and ecosystems are widespread.
1. GMFs are so labeled in Japan, Europe, South Korea, Canada, Australia, and New Zealand.
2. The U.S. Dept. of Agriculture opposed such labeling.
3. The Ecological Society of America recommended more caution in releasing genetically
engineered organisms into the environment.
4. Several scientists feel that genetic engineering of food is based on two faulty assumptions: that
world hunger is caused by a global shortage of food and that genetic engineering is the only and
best way to increase food production.
The green revolution may not be expandable indefinitely.
1. The green revolution crop varieties require huge amounts of fertilizer and water.
2. The costs of these crops are too high for subsistence farmers in developing countries.
3. There is a limit to the yield that increasing fertilizers, water, and pesticides will produce.
Eventually, there will be no additional increase in crop yield.
4. As environmental effects take place, crop yields in some areas may well begin decreasing.
5. Comparisons of yields are based on old and new monocultures rather than between even higher
yields per hectare for polyculture cropping systems.
6. Seeds used throughout the world are fairly uniform, and this increases the vulnerability of the
crops to pests, diseases, and harsh weather.
People do not try new foods easily; most will reject insects as a protein source, for example.
1. Possibilities of new food include: winged bean from SE Asia, black ant larvae from Mexico, giant
water bugs in Thailand, emperor moth caterpillars in South Africa, etc.
2. The above-mentioned protein sources are four times as protein rich as beef, fish, or eggs.
Polycultures of perennial crops have been suggested as a way to decrease tilling the soil, reduce energy
use, save water, and reduce soil erosion and water pollution.
Irrigated land per person has decreased since 1978. This is partly explained by the increasingly rapid
rise of world population, by depletion of underground aquifers, inefficient use of irrigation water, and
salt buildup in soil.
Many analysts believe that significant increase in cropland is unlikely over the next few decades.
People in urban areas should grow more of their own food—in backyards, in rooftop and balcony
gardens, etc.
Much food that is produced is wasted through spoilage, inefficient processing and preparation, and
plate waste. It is estimated that affluent countries waste nearly 60% of their food.
14-7 Producing More Meat
A. Meat and meat products are good sources of high-quality protein.
B. Producing more meat is probably not a viable solution.
1. Meat production uses much water.
2. Meat production uses more than one-third of the world’s grain. In the U.S., meat production
consumes 70% of the country’s grain.
3. Meat produces large amounts of animal waste and pollutes the environment.
4. Livestock production has an enormous impact on grain use and on the world’s catch of fish.
C. Overgrazing can lead to soil erosion and limit livestock production.
1. It lowers the net primary productivity of grassland vegetation.
2. It reduces grass cover.
3. It exposes soil to erosion by wind and water.
4. It compacts the soil.
5. It enhances the invasion of land by woody shrubs and prickly pear cactus and limits livestock
production.
D. The most widely used method for more sustainable rangeland management is to control the number of
grazing animals and the time any given area is grazed. This can be difficult to do.
1. Livestock tend to aggregate around natural water sources known as riparian zones.
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2.
Sixty-five to seventy-five percent of wildlife in the western U.S. depends totally on riparian
habitats.
3. Livestock grazing has damaged about 80% of stream and riparian ecosystems in the U.S.
4. Recovery of these areas is possible if the riparian areas are fenced off.
5. Locating waterholes/tanks and salt blocks at strategic places can also help.
6. Several methods of pest plant removal can be used such as herbicide spraying, mechanical
removal, or controlled burning.
7. Less expensive is to have controlled, short-term trampling by large numbers of livestock, then
replant with native grass seeds.
E. We can reduce the environmental impacts of meat production by shifting from less grain-efficient
forms of animal protein (beef and pork) to more grain-efficient forms (poultry and farmed fish).
F. Cattle and sheep use rangeland to eat grass, and this area is not suitable for crop-raising, so reducing
livestock production would not free up much land or grain to feed people.
14-8 Catching and Raising More Fish and Shellfish
A. Fisheries are the third major food-producing system. About 55% of the annual commercial catch of
fish and shellfish comes from the ocean. The rest comes from use of aquaculture to raise marine and
freshwater fish. like livestock in ponds and underwater cages.
B. Fish and shellfish provide about 7% of the global food supply and are the primary source of animal
protein for about 1 billion people, primarily in developing countries.
C. Commercial marine fishing is an industry that uses high tech methods to locate and harvest fish and
shellfish.
1. Trawler fishing is used to catch fish and shellfish that live on or near the ocean floor. This
involves dragging funnel-shaped, weighted nets along the bottom. This often destroys bottom
habitats and catches and kills other species such as seals and endangered or threatened species of
sea turtles.
2. Purse-seine fishing catches surface living species such as tuna, mackerel, anchovies, and herring.
Once a school of fish is located, a large net is used to surround the school and draw the net closed
like a purse string. This method has killed large numbers of dolphins.
3. Long lining involves putting out lines up to 80 miles long with thousands of hooks. This method is
used for open ocean fish like tuna, shark, and swordfish but also catches sea turtles, birds, pilot
whales, and dolphins.
4. Drift-net fishing can lead to overfishing of the desired species and may trap and kill large numbers
of unwanted fish and marine mammals. A UN ban on drift nets longer than 1.6 miles in
international waters has sharply reduced the use of this technique, but increased use of long-lines.
D. Commercial fish amounts have been declining since 1980.
1. The world’s commercially valuable marine fish are already being overfished.
a. Too little fish have been left to provide breeding stock.
b. Commercial extinction means that it is not profitable to hunt a particular species; it has almost
been eradicated by overfishing.
2. Man has raped the ocean of marine fish species and contributed to their continuing decline by
degrading the environment, destroying habitat, and polluting wetlands, estuaries, coral reefs, salt
marshes, and mangroves.
3. Commercial species may be able to come back but will need protection by fishing quotas,
restricted use of particular fishing gear/methods, and limits on fishing boats, etc.
E. Government subsidies, price controls, low-interest loans, and grants for fishing gear are major causes
of overfishing. Some of the money should be shifted to buying out some fishing boats and retraining
the crews.
F. Aquaculture is the process of raising fish and shellfish for food like crops, rather than harvesting them
in the seas and inland waters.
1. Fish farming cultivates fish in a controlled environment and harvests them at a particular size.
2. Fish ranching holds species in fenced-in areas during the time they live in saltwater and then
releases them to harvest as they spawn in freshwater.
3. The advantages and disadvantages of aquaculture are listed in Figure 14-27.
4. Use of aquaculture to grow single-celled cyanobacteria such as Spirulina has been proposed.
Spirulina is 70% protein.
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5.
Raising large, carnivorous fish in farms could deplete smaller fish species used to feed them and
could result in the collapse of both the ocean fishing industry and of aquaculture.
14-9 Government Agricultural Policy
A. Governments apply various agricultural policies to affect food production.
1. Price controls keep prices artificially low.
2. Farming subsidies and tax breaks encourage food production.
3. Allow market demand to determine prices: In this situation, poor people would suffer from likely
rising food prices. It is felt that this should be coupled with increased aid for the poor and lower
middle class.
B. Perhaps we should use subsidies for farmers who protect soil, conserve water, reforest degraded land,
etc.
14-10 Sustainable Agriculture
A. There are three main ways to reduce hunger and malnutrition and the harmful effects of agriculture.
1. Slow population growth.
2. Reduce poverty.
3. Develop and phase in systems of more sustainable or low-input agriculture (organic farming).
a. This relies more on perennial polyculture than on raising annual crops.
b. This relies on use of manure and tilled-in crop residues to build and maintain soil fertility.
c. There is very judicious use of pesticides so that pests have less chance of becoming resistant
to pesticides.
B. In 2002, agricultural scientists reported that a 21-year study comparing organic and conventional
farming methods show that there are a number of advantages to low-input organic farming.
1. Low-input farming used up to 56% less energy per unit of yield.
2. There was improved soil health and fertility.
3. This method also provides more habitats for wild plant and animal species.
C. Four major strategies have been suggested to help farmers make the transition to more sustainable
agriculture.
1. Increase research on sustainable agriculture and improving human nutrition.
2. Set up demonstration projects throughout each country for farmers.
3. Provide subsidies and increased foreign aid to encourage its use.
4. Establish training programs in sustainable agriculture for farmers and government agricultural
officials; encourage the creation of college curricula in this area.
D. The goal is to feed the world’s people while sustaining the world’s natural capital and living off the
natural income it provides.
Summary
1.
Three systems produce the foods for human consumption. Croplands produce mostly grains, about 77% of
the world’s foods. Rangelands provide meat, about 16% of the world’s food. Ocean fisheries supply about
7% of the world’s food. We must, however, produce more food for our growing world population and
increase sharply food available to the one of five people who now cannot afford sufficient food.
2.
The green revolution uses particular methods to raise crops. Monocultures are developed and planted and
bred selectively or genetically engineered to produce high yields of particular crops. Large amounts of
fertilizer, pesticides, and water are added to the crops. Yields of crops are increased through multiple
cropping throughout the year. The second green revolution since 1967 had involved using fast-growing
dwarf varieties of wheat and rice in countries with tropical and subtropical climates. Traditional agriculture
uses interplanting, several crops grown together on the same area of land; uses polyvarietal cultivation,
which grows several varieties of the same crop on the same area of land; uses agroforestry, which grows
crops and trees together; and applies polyculture, where various plants are planted together but mature at
different times.
3.
Soils are degraded and eroded by water, wind, and people. Soil erosion is primarily caused by flowing
water and wind. Human activities such as farming, logging, construction, off-road vehicles, etc. also disturb
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soil and hasten erosion. In much soil, there is also salt buildup and waterlogging. Crops can be planted
today without disturbing the soil through conservation-tillage, tillage, contour farming, and strip farming.
Farmers may also use cover crops to help hold the soil in place. Several crops planted between trees and
shrubs, alley cropping, help preserve soil and its productivity. And windbreaks are used to prevent soil’s
being blown away. Conservation and fertilization can be used to restore soil fertility, but fertilizing with
commercial pesticides brings its own set of problems.
4.
Even though food production has leveled off in the last 25 years, the world still produces enough food to
meet the basic nutritional needs of people. However, the food cannot be evenly distributed throughout the
world. The average daily intake of food has increased for people throughout the world since 1961, but at
least 15,100 people PER DAY die from poverty-related causes. Many of these deaths come from
malnutrition or lack of resistance to diseases. Modern agricultural techniques have the most harmful
environmental impact of any other human activity, especially Western farming methods. These methods are
extremely energy inefficient, using ten times more energy of nonrenewable fossil fuel to produce the food
than one unit of the energy that the food provides. This kind of waste is unacceptable. In addition,
agricultural methods pollute the environment, compromise soil (soil erosion and salinization) and water
supplies (waterlogging), and produce food that is wasted.
5.
Food production can be increased by using crossbreeding techniques on similar organisms and using
genetic engineering on different organisms. Genetic engineering, including using advanced tissue culture
techniques, is growing in use, but many people are concerned about the potential harm such crops may
cause. Irrigating more land and cultivating more land are additional solutions, but they may not prove
sustainable. Rangelands can be managed more efficiently with the land area better protected, but the
primary diet of the western world—heavy in meat and meat products—needs to be reevaluated.
Overfishing and habitat degradation dominate the marine environment; better management of this food
source and protection of the marine environment would ensure continued availability of fish worldwide.
Government policies keep food prices low and subsidize farmers who are sometimes even encouraged
NOT to plant crops. These types of artificial price controls must stop and allow food prices to be
determined by market demand. Then, the true cost of food would be charged to each person. But these
methods do not address the root cause of hunger: poverty and inequality.
6.
More sustainable agricultural systems can be created by reducing resource throughput and working with
nature. We must reduce population growth, reduce poverty, and develop low-input agriculture.
Technologies based on ecological knowledge are used to increase crop production, control pests, and build
soil fertility. Such low-input organic farming is more friendly to the environment by reducing carbon
dioxide emissions, using half the energy that conventional farming demands, and improving soil fertility.
Low-input organic farming is also more profitable for farmers. To shift to such agricultural practices, we
need more research on sustainable agriculture and the improvement of human nutrition. We also need
demonstration projects available to farmers; we need to provide subsidies and foreign aid to encourage
organic farming; and we need training programs for farmers, agricultural officials, and agricultural
schools/universities.
Test Items
See Instructor’s Manual, Section Two, p. 465.
More Depth: Conceptual Term Paper Topics
1.
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Agricultural systems: inorganic fertilizers, history of development of one crop or livestock species, green
revolution, crops with designer genes, politics of American agriculture, feedlot beef cattle production in the
Corn Belt, range livestock production in the American West, urban growth and the loss of prime cropland,
modern food storage and transportation, comparisons of environmental impacts of traditional and industrial
agricultural practices.
Section One: Chapter 14
2.
Human impact on the soil: overgrazing and desertification, acid deposition as a threat to soil quality,
sediment as a water pollutant, irrigation impacts.
3.
Soil conservation and fertility strategies: conservation-tillage farming, organic and inorganic fertilizers,
agroforestry.
4.
Hunger and food distribution: history of great famines, malnutrition and learning, the geography of
malnutrition.
5.
Fishing: overfishing, aquaculture, the Peruvian anchovy story.
More Breadth: Interdisciplinary Activities and Projects
1.
Have your students locate and bring to class photographs, paintings, or history passages describing the
effects of hunger and starvation.
2.
Ask students to find and bring to class photographs, songs, paintings, and literature reflecting human
feelings for fishermen, whalers, and farmers.
3.
Invite an agricultural economist to your class to discuss shifts in the United States from farming to
agribusiness and the historical role of subsidies in agriculture.
4.
Invite a Soil Conservation Service representative to your class to discuss local soil conservation problems
and erosion-control methods.
5.
Take a class field trip to several farms or ranches in your locale that offer you the opportunity to contrast
excellent soil management practices with poor ones.
6.
As a class exercise, discuss the economic, political, social, and environmental consequences that might
ensue if the fertile soils of the Great Plains and the Corn Belt were ruined by human-accelerated soil
erosion.
7.
With your class, visit several construction sites in your locale. Look for evidence of human-accelerated soil
erosion and methods or practices employed to minimize it.
8.
Invite a representative from the United States Department of Agriculture (or some other informed source)
to your class to discuss how U.S. political decisions such as emergency foreign aid and global trade affect
U.S. farmers.
9.
Invite a county agricultural agent to your class to discuss local agricultural problems and opportunities.
What major changes in agricultural practices are likely to occur in the coming decades? With what
consequences? What types of farming activities are carried on in your locale? What is the balance between
large and small farms? What are the major products? How much of the produce is used in local areas? How
much is shipped out and where does it go?
10. Invite an organic farmer or experienced organic gardener to address your class on the subject of alternatives
to energy-intensive agriculture. If possible, arrange a field trip to investigate organic farming practices.
Multisensory Learning: Audiovisuals
Agriculture: America’s Most Crucial Industry. 1990. 15 min. VHS/DVD. EVN.
An Incidental Kill; 1986; 28 min.; environmental hazards of efficient ocean fishing nets; DWP.
Big Spuds, Little Spuds. 1999. 52 min. BFF.
Broken Limbs: Apples, Agriculture & the New American Farmer. 2004. 57 min. BFF.
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129
Circle of Plenty; 1987; 27 min.; biointensive agriculture; BFF.
Diet for a New America; 1991; 60 min.; food choices and health of humans and the planet; VP.
Eco: The Gene Drain; 1987; 24 min.; lack of genetic diversity in crops; CTE.
Fragile Harvest; 1986; 49 min.; global agriculture and threatened genetic diversity; BFF.
Fueling the Future: Hot Wiring America’s Farms; 1988; 58 min.; examines impacts of energy-intensive
farming and explores efficient alternatives; VP.
Genetic Time Bomb; 1994; 50 min.; looks at the importance of maintaining biodiversity for new agricultural
developments; profiles the growing worldwide network of “seed savers”; VP.
Land Use Today for Tomorrow; 36 min.; soil erosion and competition for land use; CFS.
Nutrition: Eating Well; 25 min.; balanced eating; NG.
On American Soil. 1983. 28 min. BFF.
Putting Aside Pesticides; 26 min.; long-term effects of pesticides and exploration of alternatives; FHS.
Riches from the Sea; 1984; 23 min.; fish, petroleum, minerals; NG.
Save the Earth—Feed the World from Race to Save the Planet; 1990; 60 min.; intensive and traditional farming
techniques; ACPB.
Sowing for Need or Sowing for Greed? 56 min.; impacts of modern agricultural methods exported to developing
countries; BFF.
The Desert Doesn’t Doesn’t Bloom Here Anymore; 58 min.; a NOVA film examining water and irrigation
policies and how they affect soil quality; CMTI.
The End of Eden; cattle ranching, development, and the environment; TBS.
The Great Gene Robbery. 1986. 26 min. BFF.
The Living Soil: The Value of Humus.20 min. FHS.
The Miracle of Guinope; 16 min.; Honduran village successfully ends hunger and slash-and-burn agriculture;
WN.
Wheat Today, What Tomorrow? 1990; 32 min.; desertification and agriculture; BFF.
Where Have All the Dolphins Gone? 1989; 48 min.; failure of U.S. government laws to protect marine
mammals; VP.
Will the World Starve?; 58 min.; farmers, government economic policies, land degradation, poverty, and soil
erosion in Nepal, China, and Ethiopia; CMTI or CFS.
See Appendix A for suppliers.
ATTITUDES/VALUES
Assessment
1.
Have you ever fasted? If so, how did it feel?
2.
Do you feel everyone has a right to a healthy diet?
3.
Do you favor greatly increased foreign aid to poor countries to help them reduce poverty, improve
environmental quality, and develop sustainable use of their own resources?
4.
Do you favor a more equitable distribution of the world’s resources and wealth to greatly reduce the current
wide gap between the rich and the poor, even if this means less for you?
5.
What are the most common soil problems in your area?
6.
Do you feel humans have a right to use the soil in any way they choose? If not, what are the limits?
7.
Do you feel nature can take care of any harm humans bring the soil?
8.
Do you feel new technologies will solve any problems humans create with the soil?
9.
Do you feel humans have a responsibility to protect the quality and fertility of the soil? If so, what steps do
you think should be taken to protect the soil?
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Section One: Chapter 14
More Depth: Discussion and Term Paper Topics
1.
What is the best way to manage food distribution for foreign aid?
2.
Is using lifeboat ethics the best way to decide who gets to eat?
3.
Aldo Leopold’s land ethic.
4.
Is the rapid deterioration of agricultural soils in the United States a sufficiently serious problem to warrant
strict federal laws with heavy fines for farmers or ranchers failing to employ wise soil-conservation
methods? Arrange a class debate on this issue.
(Also, see text, Critical Thinking, pp. 303 and Critical Thinking and the Environment.)
PARTICIPATION
Lifestyle and Campus Community
See Green Lives/Green Campuses, Chapter 5: Soil and Food.
More Depth: Action-oriented Term Paper Topics
1.
Individual. Sustainable agriculture; organic home gardening; neglected edible plants; composting; crop
rotation; organic fertilizers; windbreaks.
2.
Global. UN food conferences; 1982 UN Conference on the Law of the Sea; agricultural training and
research centers in the developing countries; Georges Banks: conflict between Canada and Spain.
3.
Individual: soil testing methods and procedures, what individuals can do to prevent soil erosion and
nutrient depletion on their own property, agricultural practices that restore nutrients and prevent erosion,
composting, no-tillage farming; crop rotation, windbreaks, forestry practices that minimize erosion,
ranching management that minimizes erosion.
4.
National: Soil Conservation Service; policies, such as farm bills, which affect soil quality.
5.
Global: the relationship between developing countries and developed countries regarding soil erosion and
desertification.
SKILLS
Environmental Problem-solving Skills: Projects
1.
As a class, plan a daily menu for a family of four receiving minimum welfare payments (consult local
welfare agencies for current payment levels and use current food prices). Ask your students how they
would like subsisting solely on this diet.
2.
As a class exercise, determine what percentage of your diet—as individuals and as a group—consists of
meat. What are some ecological implications of this amount of meat in the diet? What are the health
implications? What are the alternatives?
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131
3.
Arrange a class debate on the proposition that food-exporting nations should use population control and
resource development as criteria to determine which of the food-importing nations will receive top priority.
Conduct a mock triage and follow it with mock appeals hearings for denied nations.
4.
As a class exercise, have your students create a soil management plan (illustrated by sketches, drawings, or
photographs) for a hypothetical badly eroded farm.
5.
Take a field trip around the community with your class. See if you can identify any sloped areas that are
eroding significantly. Try to discern if the land erosion is resulting in sediment pollution in surface waters.
Investigate if anything is being done about it. Draw up a plan that would prevent further erosion. Share it
with people who might be interested in implementing the plan.
6.
As a class, locate the nearest land undergoing desertification. If possible, take a field trip and observe it
firsthand. Research the rate of change of desertification in the last ten years. Identify any measures that
have been taken to slow the rate of desertification. Draw up a proposal that could slow the rate of
desertification.
Laboratory Skills
(none)
Computer Skills
Computerized System for Agricultural and Population Planning Assistance and Training (CAPPA)
-Facilitates use of a multisectoral scenario approach to agricultural planning.
-Chief, Development Policy Training and Research Service, Policy Analysis Division, Food and
Agriculture Organization of the United Nations, Via delle Terme di Caracalla, 00100, Rome, Italy
Standard National (Agricultural) Model (SNM)
-Analyzes the consequences of domestic or international policy changes for a nation’s domestic food
situation.
-Director, Food and Agriculture Program, International Institute for Applied Systems Analysis, Schloss
Laxenburg, A-2361, Laxenburg, Austria
Also, see Introduction to the Internet.
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Section One: Chapter 14