Food, Soil, and Pest Management

Chapter 7

Geog415

Dr Ye

What Is Food Security and Why Is It Difficult to Attain?

The greatest obstacles to providing enough food for everyone are poverty, political upheaval, corruption, war, and the harmful environmental effects of food production.

Many People Suffer from Chronic Hunger and Malnutrition

Macronutrients• Carbohydrates• Proteins• Fats

Micronutrients• Vitamins• Minerals

Many People Do No Get Enough Vitamins and Minerals

Most often vitamin and mineral deficiencies in people in developing countries

Ironimportant to store oxygen in blood, lack of it will tire easily; found in oysters, meat, poultry,

and fish; vegetable has a different form not as easy to be absorbed.

Vitamin AImportant for vision, bone growth, reproduction, etc. and also regulate immune system by

fight off infections, etc.; obtained from liver, egg, whole milk, colorful fruits and vegetables.

Iodine have a major effect on thyroid function, which controls metabolism; also important for the

formation of fetal nervous system. Obtained from certain vegetables, fruits, roots, nuts, tea, etc.

Golden rice (a genetically modified rice with a high carotene level that body converts into vitamin A to offer the third World as cure for widespread vitamin A deficiency.

Many People Have Health Problems from Eating Too Much

Overnutrition

Has similar health problems to those who are underfed• Lower life expectancy • Greater susceptibility to disease and illness• Lower productivity and life quality

Food Production Has Increased Dramatically

Three systems produce most of our food• Croplands: 77%• Rangelands, pastures, and feedlots: 16%• Aquaculture: 7%All production has been increasing since 1950.

The technology advances: increased use of tractors and farm machinery, high-tech fishing, boats and gear; inorganic chemical fertilizers, irrigation, pesticides, high-yield varieties of wheat, rice, and corn; densely populated feedlots and enclosed pens for raising cattle, pigs, and chicken, and aquaculture ponds and ocean cages for raising some types of fishes and shellfish

Food variety

The earth has 30,000 plant species with parts that people can eat. However, only 14 plants and 8 terrestrial animal species supply 90% of our global intake of calories

Three most important corps are:

1.wheat; 2. rice; 3. corn

They provide more than half of the calories in the food consumed by the world’s people (2/3 of people survive primary on these)

Fish and shellfish are in important source of food for about 1 billion people, mostly in Asia and in coastal areas of developing countries (6% protein in human diet)

Types of Food production

1. Industrialized agriculture, high-input agricultureUse large amounts of fossil fuel energy, water, commercial fertilizers and

pesticides to produce single crops (monocultures) or livestock animals for sale. It is mostly in developed countries and ¼ of all cropland)

An increasing amount of livestock production in developed countries is industrialized (feedlots fattened up for 4 month before slaughter, pigs and chickens in developed countries in densely populated pens and cages and eat mostly grain grown on cropland.

2. Plantation agriculture cash crops (bananas, coffee, soybean, sugarcane, coca, and vegetables) on large

monoculture plantations (most for sale in developed countries): a form of industrialized agriculture used primarily in tropical developing countries.

3. Traditional subsistence agriculture: use human labor and draft animals to produce only enough crops and livestock for a farm family’s survival

4. Traditional intensive agriculture: increased input of human and draft animal labor, fertilizer and water to get a higher yield per area of cultivated land. They produce enough food to feed their families and to sell for income.

3 and 4 provide 42% of world’ population, mostly in developing countries and 1/5 of world’s food supply using ¾ land cultivated land

Natural Capital: Location of the World’s Principal Types of Food Production

Green revolution

Since 1950, most of the increased in global food production has come from increased yields per unit area of cropland in a process called green revolution

Three steps:1. Develop and plant monocultures of selectively bred or genetically

engineered high-yield varieties of key crops such as rice, wheat, and corn

2. Produce high yields by using large inputs of fertilizer, pesticides, and water

3. Increase the number of crops grown per year on a plot of land through multiple cropping.

The first green revolution occurred during 1950-70 in developed countries

Second green revolution occurred since 1967 in developing countries: fast-growing dwarf varieties of rice and wheat (by Norman Bourlaf-Nobel Peace Prize winner), especially for bred for tropical and subtropical climate.

Global Outlook: Total Worldwide Grain Production (Wheat, Corn, and Rice)

Industrialized Agriculture uses ~17% of All Commercial Energy Used in the U.S.

Soil Formation and Generalized Soil Profile

Soil erosion and degradation

Land degradation occurs when natural or human induced processes decrease the future ability of land to support crops, livestock, or wild species.

Soil becomes more vulnerable to erosion through human activities that destroy plant cover, including farming, logging, construction, overgrazing by livestock, off-road vehicle use and deliberate burning of vegetation

Effect of soil erosion:

1. Loss of soil fertility through depletion of plant nutrients in topsoil

2. Pollute water, kill fish and shell fish, clog irrigation ditches, boar channels, reservoirs, and lakes by eroded soil

Natural Capital Degradation: Global Soil Erosion

Natural Capital Degradation: Severe Salinization and Waterlogging on Heavily Irrigated Land

Major Harmful Environmental Effects on Food Production

Increase crop productions: Option 1. Genetic improvements

Gene Revolution• Cross-breeding through artificial selection• Slow process

Genetic engineering• Genetic modified organisms (GMOs):

transgenic organisms

Genetic Engineering: developing crops that are resistant to• Heat and cold• Herbicides• Insect pests• Parasites• Viral diseases• Drought• Salty or acidic soil

Advanced tissue culture techniques

Fig. 7-3, p. 140

Stepped Art

Plant cell

Foreign gene integrated into plasmid DNA.

plasmid

Extract plasmidExtract DNA

Foreign geneif interest

A. tumefaciensPhase 1Gene Transfer Preparations

Cell division oftransgenic cells

Phase 3Grow GeneticallyEngineered Plant

Cultured cells divide and growinto plantlets (otherwise teleological)

Transgenic plantswith desired trait

Phase 2Make Transgenic Cell

Transgenic plant cellNucleus

Host cell

A. tumefaciens(agrobacterium)

Enzymes integrate plasmid into host cell DNA.

Agrobacterium takes up plasmid

Foreign DNA

Host DNA

GMOSWorries: know too little about the potential harm to human health and

ecosystem from the widespread use of such crops. They cannot be recalled if they cause some unintended harmful genetic and ecological effects. (some countries required labeling food: Japan, Europe, South Korea, Canada, Australia, and New Zealand; US believe they are not substantially different from foods developed by conventional crossbreeding methods)

Bad sides:1. Some requires huge amount of fertilizers and water and to insure its

higher yield2. Yield may drop as soil erodes and loses fertility, irrigated soil problems3. Crop yield may be lower than claimed because comparison was with

monoculture varieties not with polyculture cropping system4. Increased loss of biodiversity can limit the genetic raw material needed for

future green and gene revolution; genetic uniformity increase the vulnerability of food crops to pests, diseases and harsh weather

Trade-Offs: Genetically Modified Crops and Foods

Increase Crop Production: Option 2. Alternative foods

Introduce new types of food to marketsExamples:1. Winged bean in New Guinea and Southeast Asia,

faster growing, a good source of protein, editable in many parts, needs little fertilizer because of nitrogen-fixing nodules in its roots.

2. Editable insects: micro-livestock sources of protein (58-78% protein by weight, 3 or 4 times as protein-rich as beef, fish or eggs), vitamins, and minerals. 1.500 species. Black ants larvae (Taco in Mexico), giant water bugs (vegetable dips in Thailand), emperor moth caterpillars (South Africa), cockroaches (Kalahari desert dwellers), lightly toasted butterflies (Bali), fried ants (Bogota, Columbia)

3. Rely more on polycultures of perennial crops, better adopted to regional soil and climate conditions than most annual crop, eliminate the need to till soil and replant seeds each year, thus reduce energy use, soil erosion, water pollution.

Increase Crop production: option 3, irrigate more land

It is limited due to poor soils, limited water, high costs, and harmful environment effects. Clearing tropical forests and irrigating arid land could more than double the world’s cropland. But much of this is marginal land with poor soil fertility, steep slopes, or both and is likely unsustainable. Potential land lies in dry areas of Australia and Africa (expensive dam projects, fossil fuel to pump water long distance, deplete groundwater supply, etc.). In addition the increases in cropland would not offset the loss of almost 1/3 of today’s cultivated cropland caused by erosion, overgrazing, water logging, Stalinization and urbanization. It also reduce wildlife habitats and the world’s biodiversity.

Increase food production: Option 4. Producing more meat

Future increases in meat production come from densely populated feedlots, where animals are fattened for slaughter by feeding on grain grown on cropland or meat produced from fish. Feedlots account for 43% of world’s beef, half of pork, ¾ of poultry productions. Expansion of feedlot production of meat will increase the pressure on grain and fish supply (1/3 of fish is used in feeding) and has enormous environmental impact.

Efficiency of Converting Grain into Animal Protein

Increase efficiency:1. Shift to more grain-efficient forms of protein2. Shift to farmed herbivorous fish

Trade-Offs: Animal Feedlots

Increase food production: option 5. harvest more fish and shellfish

Industrial fishing fleets using GPS equipment, sonar, nets, long fishing lines, spotting planes, and large factory ships that can process and freeze their catches. This accounts for 55% of commercial catch. World’s catches start to leveled off due to overfishing, pollution, habitat loss and population growth.

Increase food production: option 6. Aquaculture

Involves raising fish and shellfish for food like crops instead of going out in fishing boats and hunting and gathering them

2 types:Fish farm: cultivating fish in a controlled environment (coastal or inland pond, lake, reservoir and rice paddy) and harvesting them when they reach the desired sizeFish ranching: holding anadromous species, such as salmon that live part of their lives fresh water and part in salt water, in captivity for the first few years of their lives, usually is fenced-in-areas or floating cages in coastal lagoons and estuaries. Then fish were released and adults are harvested when they return to spawn.

More sustainable aquaculture:

Open-ocean aquaculture

Choose herbivorous fish

Polyculture

Pests

What is a pest?Any species that compete with us for food, invade lawns and gardens,

destroys wood in houses, spreads diseases, invades ecosystems, or is simply a nuisance. (100 species of plants,-weeds; animals-insects, fungi, and microbes-infect crop plants and livestock animals, causes about 90% of the dames to crops)

Natural enemies—predators, parasites, disease organisms—control pests (up to 98%)• In natural ecosystems • In many polyculture agroecosystems • Pestcides or biocides: chemicals to kill or control population of

organisms we consider undesirable (insecticides, herbicides, fungicides, rodenticides)

Modern Synthetic Pesticides Have Several Advantages

Save human lives

Increases food supplies and profits for farmers

Work quickly

Health risks are very low relative to their benefits

New pest control methods: safer and more effective

Modern Synthetic Pesticides Have Several Disadvantages (1)

Accelerate the development of genetic resistance to

pesticides by pest organisms

Expensive for farmers

Some insecticides kill natural predators and

parasites that help control the pest population

Pollution in the environment

Some harm wildlife

Some are human health hazards

Modern Synthetic Pesticides Have Several Disadvantages (2)

David Pimentel: Pesticide use has not reduced U.S. crop loss to pests• Loss of crops is about 31%, even with 33-fold

increase in pesticide use• High environmental, health, and social costs with

use• Use alternative pest management practices

Pesticide industry refutes these findings

Trade-Offs: Conventional Chemical Pesticides

Laws and Treaties Can Help to Protect Us from the Harmful Effects of Pesticides

U.S. federal agencies• EPA• USDA• FDA

Effects of active and inactive pesticide ingredients are poorly documented

Alternatives to Using Pesticides

Fool the pest Provide homes for pest enemies Implant genetic resistance Bring in natural enemies Use insect perfumes Bring in hormones Scald them with hot water

7-5 How Can We Improve Food Security and Produce Food More Sustainably?

We can improve food security by creating programs to reduce poverty and chronic malnutrition, relying more on locally grown food, and cutting food waste.

Sustainable food production will require reducing topsoil erosion, eliminating overgrazing and overfishing, irrigating more efficiently, using integrated pest management, promoting agrobiodiversity, and providing government subsidies for more sustainable farming, fishing, and aquaculture.

Government Policies Influence Food Production and Food Security

United Nations Children’s Fund (UNICEF) suggests these measures• Immunizing children against childhood diseases• Encourage breast-feeding • Prevent dehydration in infants and children• Provide family planning services• Increase education for women

Three approaches:1. Price control: keep food prices artificially low2. Give farmer subsidies and tax breaks to keep them in business and encourage

them to increase food production ($100 billion per year in US)3. Eliminate most or all price controls and subsides and let farmers and fishers

respond to markert demand without government interference (government need to increase aid for the poor and lower middle class who suffer most from food price increase)

Soil Conservation Methods

Restore Soil Fertility

Organic fertilizer• Animal manure• Green manure• Compost

Commercial inorganic fertilizer active ingredients • Nitrogen• Phosphorous• Potassium

Shift to More Sustainable Agriculture

Strategies for more sustainable agriculture• Research on organic

agriculture with human nutrition in mind

• Show farmers how organic agricultural systems work

• Subsidies and foreign aid

• Training programs; college curricula

What Can You Do? Sustainable Organic Agriculture