LIVING WITH THE EARTH

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LIVING WITH THE EARTH
Cooking a meal in Africa
CHAPTER 3 ENVIRONMENTAL DEGRADATION AND FOOD
SECURITY
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Objectives for this Chapter

• A student reading this chapter will be able to
• 1. Discuss the impact of population on resources
  and ecosystems.
• 2. Define the following terms and explain their
  response to population growth retrogression,
  soil erosion, desertification, deforestation,
  wetlands destruction, and wildlife destruction

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Objectives for this Chapter

• 3. Define the term food security and discuss the
  reasons leading to food insecurity among many
  nations worldwide.
• 4. List the suggested steps that might be taken
  to minimize global food insecurity.

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Objectives for this Chapter

• 5. Explain the most likely reasons for a growing
  food insecurity in the United States.
• 6. List and discuss the demographics of the
  populations in the United States at risk to food
  insecurity.

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LIVING WITH THE EARTH

• ENVIRONMENTAL DEGRADATION AND FOOD SECURITY
• INTRODUCTION THE DEBATE
• The ability of our planet to sustain and feed the
  dramatic increases in human population growth has
  been an on-going debate stretching back over 200
  years.

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The Viewpoint of Malthus and Followers

• Neo-Malthusians (Malthus, 1789)
• Human growth is logarithmic and plants grow
  arithmetically. Growth will eventually surpass
  the ability of the land to feed the expanding
  population.

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Technology and Policy Will Save the Day

• Cornucopians
• The real threat to global stability is the
  failure of nations to pursue economic trade and
  research policies that increase food production,
  more evenly distribute food and resources, and
  limit environmental pollution.

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Technology and Policy Will Save the Day

• The Green Revolution
• Strains of plants are being developed that resist
  diseases, pests, drought and flooding.
• So striking has been the increased production,
  that the incorporation of these new variety of
  seeds and processes became known as the Green
  Revolution.

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The Green Revolution

• The world markets and the Green Revolution may
  promote monocultural technology that could prove
  to be ecologically unstable (Fig. 3-1).

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Fig. 3-1
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The Green Revolution

• Cross-breeding (Fig. 3-2)
• Induced Mutation (Fig. 3-2)
• Gene Transfer (Fig. 3-3)
• Precision Farming (Fig. 3-4)

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Fig. 3-2. Cross-breeding and Mutation
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Fig. 3-3. Gene Transfer
Adapted from Budiansky.6
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Fig. 3-4 Precision Farming
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The Green Revolution

• These advances in agricultural technologies have
  contributed significantly to reducing hunger in
  millions of people.
• However, the growth of the human population in
  many of the lesser developed countries has
  exceeded the capacity of even these technological
  wonders in agricultural production.

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Energy

• Wood is being used at such a rapid pace in some
  LDCs that forested regions have been decimated,
  and the collection of wood for fuel may require
  several hours each day or as much as 25 percent
  of average income.

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Energy

• On the other hand, the history of fuel use in the
  developed nations moved from wood to more
  efficient fuels.

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Energy

• The impact of human activity on environments can
  be summarized by the following relationship
• IPAT

Paul Errlich, Stanford
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Energy

• IPAT
• Where
• I the impact of human energy-related activity on
  the globe
• P is the population size
• A is the affluence in terms of per capita
  consumption
• T is the technologies to supply each unit of
  consumption

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Attitude and Behavior

• Will we progress in a smooth transition to a
  world of global stability and health, or will
  national and personal interests prevail at the
  expense of the larger global community?

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Attitude and Behavior

• What are the attitudes and behaviors that may
  have an impact on this outcome?
• Tragedy of the Commons
• Many members of any society will likely pass on
  the consequences of their destructive actions if
  they will benefit in the short term and receive
  little or no negative consequences from that
  action.

Garrett Harden
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Attitude and Behavior

• The Pioneer
• The consequences of laying waste to a land in the
  past were minimized by the ability of the
  population to emigrate.
• The pioneer mentality cannot be continued
  indefinitely in the presence of massive
  population increases.
• We must seek a sustainable development.

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Attitude and Behavior

• Declining Investment in Technologies
• Government funding for organizations which are
  largely responsible for the Green Revolution has
  been falling.
• The major gains in food crops experienced as part
  of the Green Revolution are unlikely to continue
  in the absence of investment in research and
  development.

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Attitude and Behavior

• Family Planning Cuts
• The United States reduced overall foreign
  assistance in 1996 with a 25 percent decrease in
  USAIDs funds and a 35 percent cut in the family
  planning/population assistance budget.

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These cuts could result in

• 220 million unintended pregnancies
• 117,000 additional maternal deaths and 1.5
  million women who experience permanent
  impairment
• 9.3 million additional deaths of infants and
  young children.

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IMPACTS ON THE ENVIRONMENT

• As the population increases the need for food
  increases.
• As the need for food increases, land is cleared,
  soil is degraded, and desertification occurs.

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Deforestation

• Biomes include tropical rainforests, temperate
  forests, prairies, deserts, and arctic tundra.
• The majority of tropical forest biomes occur in
  areas of the world at risk from overpopulation
  and many are being threatened with slash and burn
  techniques to make room for croplands.

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Deforestation

• Defined as the permanent decline in crown cover
  of trees to a level that is less than 10 percent
  of the original cover.

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Deforestation

• The Benefits of Rainforests are
• a major producer of oxygen for the global
  atmosphere
• the major carbon dioxide sink
• a potential source of new pharmaceuticals useful
  in the treatment of human disease
• and an important source of species diversity.

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Deforestation

• Rainforests (Fig. 3-5, 3-6)
• In spite of the numerous benefits from
  rainforests, they are disappearing at an alarming
  rate.
• By 1987, tropical rainforests were disappearing
  at the rate of 42 million acres each year,
  representing a loss of 115,000 acres each day.

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Fig. 3-5
Source from NASA..24
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Fig. 3-6
Adapted from NASA.24
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Soil Degradation

• What is soil?
• Soil consists of small particles of rock and
  minerals mixed with a major proportion of plant
  and animal matter in various stages of decay.

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Soil Degradation

• Plants are called autotrophic because they
  synthesize their own food from inorganic
  substances.
• Plants also derive nutrients from soil
• Micronutrients
• Macronutrients

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Soil Degradation

• Loam
• Soils best suited for agriculture consist of
  sand, silt, and some clay in a homogeneous
  mixture referred to as loam.
• Humus
• Complex organic matter that has been biologically
  broken down so that original plant and animal
  matter is unrecognizable.

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Soil Degradation

• Humus serves to
• retain moisture much as a sponge
• serve as an insulator to heat and cold
• and to bind and release nutrients to plants in
  useable forms.

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Fig. 3-7 Major Soil Biomes
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Soil Degradation

• Soil Erosion
• As woods are cut and fields are plowed to plant
  crops, soils are lost to the effects of wind and
  runoff water (Fig. 3-8).

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Fig. 3-8
Adapted from Turk and Turk.7
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Soil Degradation

• Farming techniques practiced to reduce soil
  erosion are
• Rotation
• Fallowing
• Terracing

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Soil Erosion

• Globally, soil erosion claims over a billion
  acres every year, and 1.2 billion acres of global
  cropland is losing topsoil so rapidly that these
  acres are expected to become unproductive in the
  next few decades.

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The Process of Desertification

• What is desertification?
• Land degradation in arid, semi-arid and dry
  sub-humid areas resulting from various factors,
  including climactic variations and human
  activities.

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Desertification

• About 15 billion acres or one third of the earth
  is dry land, and 2.5 billion (or 16 percent of
  the earths surface) of these dryland acres are
  hyperarid deserts where there is little or no
  growth.

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The Process of Desertification

• Poverty and the need for food is an enormous
  pressure that defies a flexible land use response
  and leads to desertification (Fig. 3-9).

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Fig. 3-9
Once forested land in Africa
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The Process of Desertification

• The Costs of Desertification
• Economic losses from desertification are
  calculated to be 40 billion while the cost of
  recovering these lands worldwide is estimated at
  10 billion annually.

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Wetlands What are they?

• Wetlands are those areas of land where water
  saturation is the major factor influencing the
  nature of soil development and the communities of
  plants and animals that live in the soil and on
  the surface.

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Wetlands

• Types of wetlands (Fig.3-10)
• Swamps
• Bogs
• Prairie potholes
• Bottomland Hardwood Forests
• Estuaries

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Fig. 3.10
Sourcegt USEPA, Office of Wetlands, Oceans, and
Watershed. 40
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Freshwater Marshes Swamps
Sourcegt USEPA, Office of Wetlands, Oceans, and
Watershed. 40
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Bogs
Sourcegt USEPA, Office of Wetlands, Oceans, and
Watershed. 40
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Prairie potholes
Sourcegt USEPA, Office of Wetlands, Oceans, and
Watershed. 40
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Bottomland Hardwood Forests
Sourcegt USEPA, Office of Wetlands, Oceans, and
Watershed. 40
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Coastal Marshes and Estuaries
Sourcegt USEPA, Office of Wetlands, Oceans, and
Watershed. 40
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Benefits of Wetlands

• Wetlands purify and replenish water supplies.
• Wetlands are extremely rich in biomass (the
  amount of plant and animal life).
• Wetlands are an important source of food.

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Benefits of Wetlands

• Wetlands absorb large amounts of carbon dioxide
  from the air.
• Wetlands control flooding in low-lying areas as
  they work like sponges
• Wetlands protect coastal areas from storms.
• Wetlands provide recreation and beauty.

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Wetland Losses

• An estimated 300,000 acres (120,000 hectares) of
  wetlands are drained or filled every year in the
  U.S.
• Wetlands were considered a nuisance to farmers
  and settlers and these areas were filled in.

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The Loss of Biodiversity and Extinction of Species

• Biodiversity refers to the range of animal and
  plant species and the genetic variability among
  those species.
• Why is biodiversity important?
• The greater the range of genetic variation, the
  more likely there will be a survivor species in
  the event of major catastrophies.

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The Loss of Biodiversity and Extinction of Species

• Background
• 99 of all species that ever existed are thought
  to be extinct.
• The Permian extinction caused 90 percent of all
  species in the oceans to disappear, two thirds of
  reptiles and amphibian families perished, and up
  to 30 percent of insect orders were lost.

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The Loss of Biodiversity and Extinction of Species

• Background
• Records of fossils show that entire groups of
  organisms including fish, reptiles, birds and
  mammals have replaced one another over long
  periods of time (Fig. 3-11).

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Fig. 3-11
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The Loss of Biodiversity and Extinction of Species

• Background
• It appears that the planet is now losing more
  species than are being created, and that the
  activities of humans are the reason for a rapidly
  growing species extinction and loss in
  biodiversity.

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Loss in Biodiversity

• Of the 4,327 known mammal species, 1,096 are at
  risk, and 169 are in extremely high risk of
  extinction in the wild in the immediate future
  (Fig. 3-12)

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Fig. 3-12
Adpated from Doyle. 51
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Threats to Biodiversity

• Loss of Habitat
• Most significant threat to biodivesity today is
  elimination of habitat for agriculture and
  housing. Half of 300 mussel species lost in US to
  pollution of rivers and creation of dams.
• Over-harvesting
• Cod in the North Sea off New England are heavily
  exploited with as much 60 percent of the fishable
  stock being removed annually.

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Threats to Biodiversity

• Non-native Species
• Rainbow trout never encountered whirling
  disease before the parasite was unknowingly
  transplanted here from Europe.
• Pollution
• The acidification of lakes and streams has led to
  juvenile recruitment failure among fish resulting
  in the disappearance of many species in a number
  of industrialized countries.

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Protecting Endangered and Threatened species

• Legislation first aimed at protecting wildlife in
  the United States was introduced as a bill in
  1926.
• In 1973, the Endangered Species Act (ESA) was
  promulgated in the United States (Fig. 3-13).
  The Act currently protects 1,135 speciesof plants
  and animals.

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Fig. 3-13
Sourcegt US Fish Wildlife Service Whooping
Crane-Steve Hillebrand Grizzly bear Don
Redfern Bald eagle Robert Fields Gray wolf -
USFWS
Species being restored
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Protecting Endangered and Threatened species

• Many environmentalists praise the ESA for
  reducing the extinction rate of some animal
  species in the United States, and even increasing
  numbers in as many as 65 species.
• Others have attacked the Act as interfering with
  livelihood and taking away personal property
  rights.

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Babbitt tells Nation Species protection Works

• May 7, 1998, Secretary of the Interior Bruce
  Babbitt announced 29 different animals, plants
  and birds have recovered sufficiently to take off
  the ESA list.
• Paul Nickerson, head of the Endangered Species
  Div of the Fish and Wildlife s Northeast
  Regional Office, Hadley sees continued protection
  of species under State law.

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FOOD SECURITY

• One of the biggest debates for the 21st century
  concerns whether or not the world can produce
  enough food to feed another few billion people.

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FOOD SECURITY

• Food security is said to occur when all people
  have physical and economic access to the basic
  food they need to work and function normally.

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Food Production

• For nearly 40 years, the world production of
  grain has risen by more than 2 percent a year,
  but declined to scarcely 1 percent a year in the
  1990s.

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Food Production

• Countries with critical or low food security are
  shown in figure 3-14.

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Fig. 3-14
Adapted from Brown and Kane. 69
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Reasons for Regional Food Shortages

• Food production fell behind population growth in
  64 of 105 developing countries between 1985 to
  1995.
• The main reasons for food shortages in eastern
  Africa derive mainly from recent droughts
  followed by floods.

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Reasons for Regional Food Shortages

• If countries are to feed the 9 billion expected
  by the year 2050, Africa would have to increase
  production by 300 percent, Latin America by 80
  percent, Asia by 70 percent, and North America by
  30 percent (Fig. 3-15).

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Fig.3-15
Adapted from FAO. 10
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Reasons for Regional Food Shortages

• Growth rates in cereal production have been
  declining from 2.8 percent in the 1960s, to
  nearly 2.1 percent in 1992 (Fig. 3-16).

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Fig. 3-16
Adapted from FAO. 10
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Sources Where will the Food Come From?

• Increases in food supply must come from one or
  more of the following sources (Fig. 3-17)
• increases in yield (tons per acre)
• increases in arable land placed under
  cultivation
• and cropping intensity (fewer fallow periods or
  more than one crop per year or field).

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Fig. 3-17
Adapted from FAO. 10
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Sources

• There are scientists who believe that the ability
  to expand cropland is limited, and that it is
  disappearing in many areas of the world.

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Sources

• The potential for increasing agricultural land is
  limited by
• the significant costs of developing an
  infrastructure in remote areas
• the lesser productivity of these alternative
  areas
• and the trade-offs in environmental destruction
  of sensitive ecosystems.

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Sources

• Alternative strategies are being evaluated and
  promoted that are more friendly to the
  environment.

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Sources

• These strategies are
• improved irrigation systems
• structured water pricing to reduce overuse
• alternative rotation of crops
• selective pesticide use

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Sources

• These strategies are
• use of pest-resistant varieties
• improved soil testing and fertilizer application
  
• regional crop breeding programs
• and more education to farmers.

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Food Security

• Worldwide
• Chronic undernutrition is a difficult and
  pervasive problem resulting in a food security
  crisis in many LDCs.
• Net imports to LDCs are expected to increase from
  90 to 160 million tons in the years from 1990 to
  2010.

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Hunger in America

• More than 25 million Americans, almost 50 percent
  of them under 17, resort to using food
  distribution programs such as soup kitchens and
  food pantries (Fig. 3-18).
• Nearly 35 million Americans live in hungry or
  food-insecure households.

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Fig. 3-18
Adapted from Roberts and Roberts. 80