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ENVIRONMENTAL DEGRADATION AND FOOD SECURITY - Moore 1

LIVING WITH THE EARTH

Cooking a meal in

Africa


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



– 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.



– 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.


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.


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.


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.


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.”


The Green Revolution

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


Fig. 3-1



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


Fig. 3-2. Cross-breeding and Mutation


Fig. 3-3. Gene TransferAdapted from Budiansky.6


Fig. 3-4 Precision Farming



– 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.


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.


Energy

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


Energy

– The impact of human activity on environments can be summarized by the following relationship:

I=P*A*T

Paul Errlich, Stanford


EnergyI=P*A*T

–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


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?



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



• 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.



• 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.



• 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.


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.


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.


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.


Deforestation

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


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.


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.


Fig. 3-5Source from NASA..24


Fig. 3-6Adapted from NASA.24


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.


Soil Degradation

– Plants are called autotrophic because they synthesize their own food from inorganic substances.

– Plants also derive nutrients from soil• Micronutrients• Macronutrients


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.


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.


Fig. 3-7 Major Soil Biomes


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).


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


Soil Degradation

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


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.


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.


Desertification

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



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


Fig. 3-9

Once forested land in Africa



• 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.


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.


Wetlands

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


Fig. 3.10Source> USEPA, Office of Wetlands, Oceans, and Watershed. 40


Freshwater Marshes & SwampsSource> USEPA, Office of Wetlands, Oceans, and Watershed. 40


BogsSource> USEPA, Office of Wetlands, Oceans, and Watershed. 40


Prairie potholesSource> USEPA, Office of Wetlands, Oceans, and Watershed. 40


Bottomland Hardwood ForestsSource> USEPA, Office of Wetlands, Oceans, and Watershed. 40


Coastal Marshes and EstuariesSource> USEPA, Office of Wetlands, Oceans, and Watershed. 40


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.


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.


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.


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.



• 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.



• 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).


Fig. 3-11



• 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.


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)


Fig. 3-12Adpated from Doyle. 51


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.


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.


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 speciesofplants and animals.


Fig. 3-13

Species being restored

Source> US Fish & Wildlife Service: Whooping Crane-Steve Hillebrand; Grizzly bear – Don Redfern; Bald eagle – Robert Fields; Gray wolf - USFWS


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.


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.


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.


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.


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.


Food Production

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


Fig. 3-14Adapted from Brown and Kane. 69


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.



– 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).


Fig.3-15Adapted from FAO. 10



– 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).


Fig. 3-16Adapted from FAO. 10


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).


Fig. 3-17Adapted from FAO. 10


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.


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.


Sources

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


Sources

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


Sources

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


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.


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.


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

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