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Chapter 15
Food and Agriculture
Table of Contents
Section 1 Feeding the World
Section 2 Crops and Soil
Section 3 Animals and Agriculture
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Chapter 15
Section 1 Feeding the World
Objectives
• Identify the major causes of malnutrition.
• Compare the environmental costs of producing
different types of food.
• Explain how food distribution problems and drought
can lead to famine.
• Explain the importance of the green revolution.
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Chapter 15
Section 1 Feeding the World
Feeding the World
• Famine is the widespread malnutrition and starvation
in an area due to a shortage of food, usually caused
by a catastrophic event.
• Modern agriculture practices provide most of the
world’s population with enough food to survive.
• However, some of these practices can cause
environmental damage that eventually makes
growing food crops more difficult.
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Chapter 15
Section 1 Feeding the World
Humans and Nutrition
• The human body uses food both as a source of
energy and as a source of materials for building and
maintaining body tissues.
• The amount of energy that is available in food is
expressed in Calories. One Calorie is equal to 1,000
calories or one kilocalorie.
• The major nutrients we get from food are
carbohydrates, proteins, and lipids. Our bodies need
smaller amounts of vitamins and minerals to remain
healthy.
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Chapter 15
Section 1 Feeding the World
Humans and Nutrition
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Chapter 15
Section 1 Feeding the World
Humans and Nutrition
• Malnutrition is a disorder of nutrition that results
when a person does not consume enough of each of
the nutrients that are needed by the human body.
• There are many forms of malnutrition. For example,
humans need to get 8 essential amino acids from
proteins. This is easily done if a variety of foods is
eaten. However, in some parts of the world, the only
sources of food may be corn and rice, which contain
protein, but lacks one of the essential amino acids.
Amino acid deficiency can result from such a limited
diet.
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Chapter 15
Section 1 Feeding the World
Sources of Nutrition
• Diet is the type and amount of food that a person
eats. A healthy diet is one that maintains a balance of
the right amounts of nutrients, minerals, and vitamins.
• The foods produced in the greatest amounts
worldwide are grains, plants of the grass family
whose seeds are rich in carbohydrates.
• Besides eating grains, most people eat fruits,
vegetables, and smaller amounts of meats, nuts, and
other foods that are rich in fats and proteins.
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Chapter 15
Section 1 Feeding the World
Sources of Nutrition
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Chapter 15
Section 1 Feeding the World
Diets Around the World
• People worldwide generally consume the same major
nutrients and eat the same basic kinds of food.
• But, diets vary by region.
• People in more developed countries tend to eat more
food and a larger proportion of proteins and fats than
people in less developed countries.
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Chapter 15
Section 1 Feeding the World
Diets Around the World
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Chapter 15
Section 1 Feeding the World
The Ecology of Food
• As the human population grows, farmland replaces
forests and grasslands.
• Feeding everyone while maintaining natural
ecosystems becomes increasingly difficult.
• Different kinds of agriculture have different
environmental impacts and different levels of
efficiency.
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Chapter 15
Section 1 Feeding the World
Food Efficiency
• The efficiency of a given type of agriculture is a
measure of the quantity of food produced on a given
area of land with limited inputs of energy and
resources.
• An ideal food crop is one that efficiently produces a
large amount of food with little negative impact on the
environment.
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Chapter 15
Section 1 Feeding the World
Food Efficiency
• On average, more energy, water, and land are used
to produced a Calorie of food from animals than to
produce a Calorie of food from plants.
• Animals that are raised for human use are usually fed
plant matter, but because less energy is available at
each level on a food chain, only about 10 percent of
the energy from the plants gets stored in the animals.
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Chapter 15
Section 1 Feeding the World
Food Efficiency
• Thus, a given area of land can usually produce more
food for humans when it is used to grow plants than
when it is used to raise animals.
• The efficiency of raising plants for food is one reason
why diets around the world are largely based on
plants.
• However, meat from animals generally provides more
nutrients per gram than most food from plants.
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Chapter 15
Section 1 Feeding the World
Old and New Foods
• Researchers hope to improve the efficiency of food
production by studying plants and other organisms
that have high yield.
• Yield is the amount of crops produced per unit area.
• Researchers are interested in organisms that can
thrive in various climates and that do not require
large amounts of fertilizer, pesticides, or fresh water.
Some organisms have been a source of food for
centuries, while other sources are just being
discovered.
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Chapter 15
Section 1 Feeding the World
World Food Problems
• Some people become malnourished because they
simply do not get enough food.
• More food is needed each year to feed the world’s
growing population.
• World food production has been increasing for
decades, but now food production is not increasing
as fast as the human population is increasing.
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Chapter 15
Section 1 Feeding the World
World Food Problems
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Chapter 15
Section 1 Feeding the World
Unequal Distribution
• If all the food in the world today were divided equally
among the human population, no one would have
quite enough food for good health.
• But food is not divided equally, and malnutrition is
largely the result of poverty. Even in the United
States, many poor people suffer from malnutrition.
• Wars and political strife can also lead to malnutrition
because they interrupt transportation systems.
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Chapter 15
Section 1 Feeding the World
Droughts and Famines
• A drought is a prolonged period during which rainfall
is below average, and crops grown without irrigation
may produce low yields or fail entirely.
• A drought is more likely to cause famine in places
where most food is grown locally.
• If a drought occurs, there may be no seed to plant
crops the following year. The effects of a drought can
continue for years.
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Chapter 15
Section 1 Feeding the World
Drought and Famines
• People in a given area can usually survive one crop
failure. They may have saved enough food from
previous seasons, or they may have systems for
importing food from elsewhere.
• But several years of drought cause severe problems
for any area of the world.
• For example, after a long drought, the soil may be
less able to support the production of food crops.
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Chapter 15
Section 1 Feeding the World
The Green Revolution
• Worldwide, between 1950 and 1970, increases in
crop yields resulted from the use of new crop
varieties and the application of modern agriculture
techniques.
• These changes were called the green revolution.
Since the 1950s, the green revolution has changed
the lives of millions of people.
• However, the green revolution also had some
negative effects.
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Chapter 15
Section 1 Feeding the World
The Green Revolution
• For example, most new varieties of grain produce
large yields only if they receive large amounts of
water, fertilizer, and pesticides. In addition, the
machinery, irrigation, and chemicals required by new
crop varieties can degrade the soil if they are not
used properly.
• As a result of the overuse of fertilizers and pesticides,
yields from green revolution crops are falling. The
grain production in the U.S. has decreased since
1990, partly because the amount of water used for
irrigation has decreased.
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Chapter 15
Section 1 Feeding the World
The Green Revolution
• In addition, the green revolution had a negative
impact on subsistence farmers, or farmers who grow
only enough food for local use.
• Before the green revolution, subsistence farmers
worked most of the world’s farms.
• But they could not afford the equipment, water, ad
chemicals needed to grow new crop varieties.
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Chapter 15
Section 2 Crops and Soil
Objectives
• Distinguish between traditional and modern agricultural
techniques.
• Describe fertile soil.
• Describe the need for soil conservation.
• Explain the benefits and environmental impacts of
pesticide use.
• Explain what is involved in integrated pest management.
• Explain how genetic engineering is used in agriculture.
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Chapter 15
Section 2 Crops and Soil
Crops and Soil
• Arable land is farmland that can be used to grow
crops.
• The Earth has only a limited area of arable land.
• But, as the human population continues to grow, the
amount of arable land per person decreases.
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Chapter 15
Section 2 Crops and Soil
Agriculture: Traditional
• The basic processes of farming include plowing,
fertilization, irrigation, and pest control.
• Traditionally, plows are pushed by the farmers or
pulled by livestock. Plowing helps crops grow by
mixing soil nutrients, loosening soil particles, and
uprooting weeds. Organic fertilizers, such as manure,
are used to enrich soil. While fields are irrigated by
water flowing through ditches.
• These traditional techniques have been used since
the earliest days of farming.
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Chapter 15
Section 2 Crops and Soil
Agriculture: Modern
• In most industrialized countries, the basic processes
of farming are now carried out using modern
agricultural methods.
• Machinery powered by fossil fuels is now used to
plow the soil and harvest crops. Synthetic chemical
fertilizers have replaced manure and plant wastes to
fertilize soil.
• A variety of overhead sprinklers and drip systems
may be used for irrigation. And synthetic chemicals
are used to kill pests.
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Chapter 15
Section 2 Crops and Soil
Fertile Soil: The Living Earth
• Soil that can support the growth of healthy plants is
called fertile soil.
• Topsoil is the surface layer of the soil, which is
usually richer in organic matter than the subsoil is.
• Fertile topsoil is composed of living organisms, rock
particles, water, air, and organic matter, such as dead
or decomposing organisms. Several layers of soil lie
under the topsoil. The bottom layer is bedrock, which
is the solid rock from which most soil originally forms.
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Chapter 15
Section 2 Crops and Soil
Fertile Soil: The Living Earth
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Chapter 15
Section 2 Crops and Soil
Fertile Soil: The Living Earth
• Most soil forms when rock is broken down into
smaller and smaller fragments by wind, water, and
chemical weathering. Chemical weathering happens
when the minerals in rock react chemically with
substances to form new materials. Temperature
changes and moisture can also cause rock to crack
and break apart.
• It can take hundreds or even thousands of years for
these geological processes to form a few centimeters
of soil.
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Chapter 15
Section 2 Crops and Soil
Fertile Soil: The Living Earth
• Other processes also help to produce fertile topsoil.
For example, the rock particles supply mineral
nutrients to the soil.
• Fungi and bacteria live in the soil, and they
decompose dead plants as well as organic debris
and add more nutrients to the soil.
• Earthworms, insects, and other small animals help
plants grow by breaking up the soil and allowing air
and water into it.
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Chapter 15
Section 2 Crops and Soil
Fertile Soil: The Living Earth
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Chapter 15
Section 2 Crops and Soil
Soil Erosion: A Global Problem
• Erosion is a process in which the materials of the
Earth’s surface are loosened, dissolved, or worn
away and transported from one place to another by a
natural agent, such as wind, water, ice, or gravity.
• In the U.S., about half of the original topsoil has been
lost to erosion in the past 200 years.
• Without topsoil, crops cannot be grown. Yet, almost
all farming methods increase the rate of soil erosion.
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Chapter 15
Section 2 Crops and Soil
Soil Erosion: A Global Problem
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Chapter 15
Section 2 Crops and Soil
Land Degradation
• Land degradation happens when human activity or
natural processes damage the land so that it can no
longer support the local ecosystem. In areas with dry
climates, desertification can occur.
• Desertification is the process by which human
activities or climatic changes make arid or semiarid
areas more desertlike.
• This process is causing some of our arable land to
disappear.
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Chapter 15
Section 2 Crops and Soil
Land Degradation
• For example, in the past, people who lived in the drier
part of the Sahel region in Africa grazed animals,
while people in the wetter part of the region planted
crops.The grazing animals were moved from place to
place to find fresh grass. The cropland was planted
for only a few years, and then allowed to lie fallow, or
to remain unplanted, for several years.
• These methods allowed the land to adequately
support the people in the Sahel.
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Chapter 15
Section 2 Crops and Soil
Land Degradation
• But the population in the region has grown, and the
land is being farmed, grazed, and deforested faster
than it can regenerate. Crops are planted too
frequently and fallow periods are being shortened or
eliminated completely.
• As a result, the soil is losing fertility and productivity.
Because of overgrazing, the land has fewer plants to
hold the topsoil in place.
• So, large areas have become desert and can no
longer produce food.
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Chapter 15
Section 2 Crops and Soil
Soil Conservation
• There are many ways of protecting and managing
topsoil and reducing erosion.
• Soil usually erodes downhill, and many soil
conservation methods are designed to prevent
downhill erosion.
• For example, soil-retaining terraces can be build
across a hillside. On gentler slopes, contour plowing,
which consists of plowing across the slope of a hill
instead of up and down the slope, can be used.
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Chapter 15
Section 2 Crops and Soil
Soil Conservation
• An even more effective method of plowing is leaving
strips of vegetation across the hillside instead of
plowing the entire slope.
• These strips catch soil and water that run down the
hill.
• Still, many areas of land that have hills are not suited
to farming, but may be better used as forest or
grazing land.
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Chapter 15
Section 2 Crops and Soil
Soil Conservation
• In no-till farming, a crop is harvested without turning
the soil over, as in traditional farming.
• Later, the seeds of the next crop are planted among
the remains of the previous crop. The remains of the
first crop hold the soil in place while the new crop
develops.
• Although this method saves time and reduces soil
erosion, it is not suited for all crops. Other
disadvantages include soil that is too densely packed
and lower crop yields over time.
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Chapter 15
Section 2 Crops and Soil
Enriching the Soil
• Soil was traditionally fertilized by adding organic
matter that would decompose, adding nutrients to the
soil and improving the soil texture.
• However, inorganic fertilizers that contain nitrogen,
phosphorous, and potassium have changed farming
methods. Without them, world food production would
be less than half of what it is today.
• If erosion occurs in areas fertilized with inorganic
materials, waterways may become polluted.
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Chapter 15
Section 2 Crops and Soil
Enriching the Soil
• Over the past 50 years, the
use of such inorganic
fertilizers has increased
rapidly.
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Chapter 15
Section 2 Crops and Soil
Enriching the Soil
• A modern method of enhancing the soil is to use both
organic and inorganic materials by adding compost
and chemical fertilizers to the soil.
• Compost is a mixture of decomposing organic
matter, such as manure and rotting plants, that is
used as fertilizer and soil conditioner.
• Many cities and industries now compost yard and
crop wastes. This compost is then sold to farmers
and gardeners, and the process is saving costly land
fill space.
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Chapter 15
Section 2 Crops and Soil
Salinization
• The accumulation of salts in the soil is known as
salinization.
• Salinization is a major problem in places that have
low rainfall and naturally salty soil.
• When water evaporates from irrigated land, salts are
left behind.
• Salinization can be slowed if irrigation canals are
lined to prevent water from seeping into the soil, or if
the soil is watered heavily to wash out salts.
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Chapter 15
Section 2 Crops and Soil
Pest Control
• Worldwide, pests destroy about one-third of the
world’s potential food harvest.
• A pest is any organism that occurs where it is not
wanted or that occurs in large enough numbers to
cause economic damage.
• Humans try to control populations of many types of
pests, including plants, fungi, insects, and
microorganisms.
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Chapter 15
Section 2 Crops and Soil
Pesticides
• Many farmers rely on pesticides to produce their
crops.
• A pesticide is a poison used to destroy pests, such
as insects, rodents, or weeds; examples include
insecticides, rodenticides, and herbicides.
• Pesticides, however, can also harm beneficial plants
and insects, wildlife, and even people.
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Chapter 15
Section 2 Crops and Soil
Pesticide Resistance
• Over time, spraying large amounts of pesticide to get
rid of pests usually makes the pest problem worse.
• Pest populations may evolve resistance, the ability to
survive exposure to a particular pesticide.
• More than 500 species of insects have developed
resistance to pesticides since the 1940s.
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Chapter 15
Section 2 Crops and Soil
Human Health Concerns
• Pesticides are designed to kill organisms, so they
may also be dangerous to humans.
• Cancer rates among children in areas where large
amounts of pesticides are used on crops are
sometimes higher than the national average.
• People who apply pesticides need to follow safety
guidelines to protect themselves from contact with
these chemicals.
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Chapter 15
Section 2 Crops and Soil
Pollution and Persistence
• The problem of pesticides harming people and other
organisms is especially serious with pesticides that
are persistent.
• A pesticide is persistent if it does not break down
easily or quickly in the environment.
• Persistent pesticides do not break down into
harmless chemicals, and they accumulate in the
water and soil.
• Some pesticides have been banned in the United
States for decades but can still be detected in the
environment.
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Chapter 15
Section 2 Crops and Soil
Biological Pest Control
• Biological pest control is the use of certain
organisms by humans to eliminate or control pests.
• Every pest has enemies in the wild, and these
enemies can sometimes be used to control pest
populations.
• Biological pest control includes the use of
• pathogens,
• plant defenses,
• chemicals from plants,
• and the disrupting of insect breeding
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Chapter 15
Section 2 Crops and Soil
Integrated Pest Management
• Integrated pest management is a modern method of
controlling pests on crops.
• The goal of integrated pest management is not to
eliminate pest populations but to reduce pest damage
to a level that causes minimal economic damage.
• Such programs can include a mix of farming
methods, biological pest control, and chemical pest
control.
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Chapter 15
Section 2 Crops and Soil
Integrated Pest Management
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Chapter 15
Section 2 Crops and Soil
Integrated Pest Management
• Biological methods are the first methods used to
control the pest. So, natural predators, pathogens,
and parasites of the pest may be introduced.
• Cultivation controls, such as vacuuming insects off
the plants, can also be used.
• As a last resort, small amounts of insecticides may
be used. These insecticides are changed over time to
reduce the ability of pests to evolve resistance.
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Chapter 15
Section 2 Crops and Soil
Engineering a Better Crop
• Genetic engineering is a technology in which the
genome of a living cell is modified for medical or
industrial use.
• Scientists may use genetic engineering to transfer
desirable traits, such as resistance to certain pests,
from one organism to another.
• Plants that result from genetic engineering are called
genetically modified (GM) plants.
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Chapter 15
Section 2 Crops and Soil
Engineering a Better Crop
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Chapter 15
Section 2 Crops and Soil
Implications of Genetic Engineering
• In the United States, we now eat and use genetically
engineered agricultural products everyday.
• Many of these products, however, have not been fully
tested for their environmental impacts.
• Some scientists warn that these products will cause
problems in the future.
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Chapter 15
Section 2 Crops and Soil
Sustainable Agriculture
• Farming that conserves natural resources and helps
keep the land productive indefinitely is called
sustainable agriculture.
• Sustainable agriculture involves planting productive,
pest-resistant crop varieties that require little energy,
pesticides, fertilizer, and water.
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Chapter 15
Section 3 Animals and
Agriculture
Objectives
• Explain how overharvesting affects the supply of
aquatic organisms used for food.
• Describe the current role of aquaculture in providing
seafood.
• Describe the importance of livestock in providing
food and other products.
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Chapter 15
Section 3 Animals and
Agriculture
Animals and Agriculture
• Food from animals has been the basis of life for
some human populations for centuries.
• Our ancestors obtained animal protein by hunting
and fishing. Today, most people get animal protein
from domesticated species.
• Domesticated describes organisms that have been
bred and managed for human use.
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Chapter 15
Section 3 Animals and
Agriculture
Food from Water
• Because fish are an important food source for
humans, the harvesting of fish has become an
important industry worldwide.
• However, when too many fish are harvested over a
long period of time, ecological systems can be
damaged.
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Chapter 15
Section 3 Animals and
Agriculture
Food from Water
The North Atlantic cod fishery has collapsed
because too many fish were harvested over time.
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Chapter 15
Section 3 Animals and
Agriculture
Overharvesting
• Overharvesting is the catching or removing from a
population more organisms than the population can
replace.
• Many governments are now trying to stop
overharvesting. They have created no-fishing zones,
so that fish populations can recover.
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Chapter 15
Section 3 Animals and
Agriculture
Aquaculture
• Aquaculture is the raising of aquatic plants and
animals for human use or consumption.
• Fish and other aquatic organisms provide up to 20
percent of the animal protein consumed worldwide.
• Aquaculture may be one solution to the
overharvesting of fish and other organisms
in the world’s oceans.
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Chapter 15
Section 3 Animals and
Agriculture
Aquaculture
• Aquaculture is not a new idea.
• This practice probably began in China about 4,000
years ago.
• Today, China leads the world in using aquaculture to
produce freshwater fish.
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Chapter 15
Section 3 Animals and
Agriculture
Aquaculture
• There are a number of different methods of
aquaculture. Among these are
• Fish farming
• Fish ranching
• Fish farms generally consist of many individual ponds
that each contain fish at a specific stage of
development. Fish grow to maturity in the ponds and
are then harvested.
• Fish ranches raise fish to a certain age, release them
to the ocean, and then harvest the adults when they
return to their birthplace to breed.
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Chapter 15
Section 3 Animals and
Agriculture
Aquaculture
• As with other methods of food production, however,
aquaculture can cause environmental damage if not
managed properly.
• Aquatic organisms can produce a large amount of
waste, which can be a source of pollution.
• Because aquaculture requires so much water, the
process can deplete local water supplies.
• Despite these problems, aquaculture will continue to
be an important source of protein for the human
diet.
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Chapter 15
Section 3 Animals and
Agriculture
Livestock
• Livestock is the term given to domesticated animals
that are raised to be used on a farm or ranch or to be
sold for profit.
• Populations of livestock have changed dramatically in
the last 40 years.
• Large livestock operations produce most of the meat
that is consumed in developed countries.
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Chapter 15
Section 3 Animals and
Agriculture
Livestock
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Chapter 15
Section 3 Animals and
Agriculture
Livestock
• In developing countries, livestock not only provide
leather, wool, eggs, and meat, but also serve other
functions.
• Some livestock are used as draft animals to pull carts
and plows.
• Other livestock provide manure as the main source of
plant fertilizer or as a fuel for cooking.
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Chapter 15
Section 3 Animals and
Agriculture
Ruminants
• Ruminants are cud-chewing mammals that have a
three- or four-chambered stomach.
• Cattle, sheep, and goats are examples of ruminants.
• Cud is the food that these animals regurgitate from
the first chamber of their stomachs and chew again to
aid digestion.
• When we eat the meat of ruminants, we are using
them to convert plant material, such as grass stems
and woody shrubs, into food that we can digest—
such as beef.
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Chapter 15
Section 3 Animals and
Agriculture
Ruminants
• Humans have created hundreds of breeds of cattle
that are suited to life in different climates.
• Worldwide meat production per person has increased
significantly since 1950.
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Chapter 15
Section 3 Animals and
Agriculture
Poultry
• Since 1961, the population of chickens worldwide has
increased to a greater percentage than the
population of any other livestock.
• Chickens are a type of poultry, domesticated birds
raised for meat and eggs.
• In more-developed countries, chickens and turkeys
are usually raised in factory farms.
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Chapter 15
Section 1 Feeding the World
Bellringer
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Chapter 15
Section 1 Feeding the World
World Calorie Consumption
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Chapter 15
Section 1 Feeding the World
World Grain Production Vs. Grain Production
per Person
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Chapter 15
Section 2 Crops and Soil
Bellringer
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Chapter 15
Section 2 Crops and Soil
The Structure and Composition of Soil
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Chapter 15
Section 2 Crops and Soil
Worldwide Vulnerability of Soils to Water
Erosion
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Chapter 15
Section 2 Crops and Soil
The Steps of Integrated Pest Management
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Chapter 15
Section 2 Crops and Soil
Engineering Plant Resistance to Insect Pests
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Chapter 15
Section 3 Animals and
Agriculture
Bellringer
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Chapter 15
Section 3 Animals and
Agriculture
The Collapse of the North Atlantic Cod Fishery
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Chapter 15
Standardized Test Prep
Multiple Choice
1. Which of the following is a major cause of famine in
the world today?
A.
B.
C.
D.
food efficiency
improved yield
lack of rainfall
no-till farming
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Chapter 15
Standardized Test Prep
Multiple Choice
1. Which of the following is a major cause of famine in
the world today?
A.
B.
C.
D.
food efficiency
improved yield
lack of rainfall
no-till farming
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Chapter 15
Standardized Test Prep
Multiple Choice, continued
2. What is the main difference between fertile and
infertile soil?
F. Fertile soil supports plant life; infertile soil cannot.
G. Infertile soil supports plant life; fertile soil cannot.
H. Fertile soil supports insect life; infertile soil
cannot.
I. Infertile soil support insect life; fertile soil cannot.
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Chapter 15
Standardized Test Prep
Multiple Choice, continued
2. What is the main difference between fertile and
infertile soil?
F. Fertile soil supports plant life; infertile soil cannot.
G. Infertile soil supports plant life; fertile soil cannot.
H. Fertile soil supports insect life; infertile soil
cannot.
I. Infertile soil support insect life; fertile soil cannot.
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Chapter 15
Standardized Test Prep
Multiple Choice, continued
3. What is the eventual result of land degradation?
A.
B.
C.
D.
desertification
fertilization
integration
salinization
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Chapter 15
Standardized Test Prep
Multiple Choice, continued
3. What is the eventual result of land degradation?
A.
B.
C.
D.
desertification
fertilization
integration
salinization
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Chapter 15
Standardized Test Prep
Multiple Choice, continued
4. Which of the following is an effect of soil erosion?
F.
G.
H.
I.
increased crop yields
increase in land fertility
decrease in desertification
decrease in amount of top soil
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Chapter 15
Standardized Test Prep
Multiple Choice, continued
4. Which of the following is an effect of soil erosion?
F.
G.
H.
I.
increased crop yields
increase in land fertility
decrease in desertification
decrease in amount of top soil
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Chapter 15
Standardized Test Prep
Multiple Choice, continued
Use this graph to answer questions 5 through 7.
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Chapter 15
Standardized Test Prep
Multiple Choice, continued
5. In what year did the total amount of grain production
equal the average amount of grain per person?
A.
B.
C.
D.
1980
1983
1986
1989
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Chapter 15
Standardized Test Prep
Multiple Choice, continued
5. In what year did the total amount of grain production
equal the average amount of grain per person?
A.
B.
C.
D.
1980
1983
1986
1989
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Chapter 15
Standardized Test Prep
Multiple Choice, continued
6. What is the main reason that, while total grain
production has increased each year, the amount of
grain per person has been relatively steady?
F. Much of the grain produced could not be
distributed efficiently.
G. The world’s population has grown faster than
grain production.
H. The world’s population has remained roughly the
same for the last 30 years.
I. Much of the grain produced in the world was
used to feed livestock or as seed.
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Chapter 15
Standardized Test Prep
Multiple Choice, continued
6. What is the main reason that, while total grain
production has increased each year, the amount of
grain per person has been relatively steady?
F. Much of the grain produced could not be
distributed efficiently.
G. The world’s population has grown faster than
grain production.
H. The world’s population has remained roughly the
same for the last 30 years.
I. Much of the grain produced in the world was
used to feed livestock or as seed.
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Chapter 15
Standardized Test Prep
Multiple Choice, continued
7. If the trend that was in place from 1990–1995
continues through 2005, what will be the average
amount of grain available per person?
A.
B.
C.
D.
200 kg
250 kg
300 kg
350 kg
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Chapter 15
Standardized Test Prep
Multiple Choice, continued
7. If the trend that was in place from 1990–1995
continues through 2005, what will be the average
amount of grain available per person?
A.
B.
C.
D.
200 kg
250 kg
300 kg
350 kg
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Chapter 15
Section 1 Feeding the World
Image and Activity Bank
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Chapter 15
Section 1 Feeding the World
Image and Activity Bank
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Chapter 15
Section 1 Feeding the World
Image and Activity Bank
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Chapter 15
Section 1 Feeding the World
Image and Activity Bank
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Chapter 15
Section 1 Feeding the World
Image and Activity Bank
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Chapter 15
Section 2 Crops and Soil
Image and Activity Bank
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Chapter 15
Section 2 Crops and Soil
Image and Activity Bank
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Chapter 15
Section 2 Crops and Soil
Image and Activity Bank
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Chapter 15
Section 2 Crops and Soil
Image and Activity Bank
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Chapter 15
Section 2 Crops and Soil
Image and Activity Bank
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Chapter 15
Section 2 Crops and Soil
Image and Activity Bank
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Chapter 15
Section 2 Crops and Soil
Image and Activity Bank
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Chapter 15
Section 3 Animals and
Agriculture
Image and Activity Bank
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Chapter 15
Section 3 Animals and
Agriculture
Image and Activity Bank
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Chapter 15
Section 3 Animals and
Agriculture
Image and Activity Bank
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Chapter 15
Section 3 Animals and
Agriculture
Image and Activity Bank
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