Chapter 11 Feeding the World

White boards The world grows enough food for everyone, why are people still hungry?

White Boards List the factors that have contributed to America’s obesity problem.

Nutrition Chronic under nutrition -means not consuming enough calories to be healthy Malnourished- is regardless of calories diets lack balance one half of the world is malnourished Overnutrition -is the ingestion of too many calories and improper foods that can cause a person to become overweight

Reasons for Undernutrition and Malnutrition Poverty Political and economic factors Agricultural resources being diverted to feed livestock and poultry rather than people Eating unhealthy food

Guess a country that could collapse from food shortages? Somalia ■ Sudan ■ Zimbabwe ■ Chad ■ Iraq ■ Democratic Republic of the Congo ■ Afghanistan ■ Ivory Coast ■ Pakistan ■ Central African Republic ■ Guinea ■ Bangladesh ■ Burma (Myanmar) ■ Haiti ■ North Korea ■ Ethiopia ■ Uganda ■ Lebanon ■ Nigeria ■ Sri Lanka

The Green Revolution New management techniques and mechanization as well as the triad of fertilization, irrigation, and improved crop varieties. This has increased food production dramatically.

Green Revolution led to Industrial Farming With fossil fuel use came more efficient farming and this led to industrial agriculture Energy subsidy –the energy input per calorie of food produced For example if we used 5 calories to produce food and we receive 1 when we eat that food then the food has an energy subsidy of 5. Increasing the Yield Per Acre Programs that have led to the development of new strains of crops with higher yields, better resistance to disease or better ability to grow under poor conditions Improved Irrigation Fertilizers Mechanization

Mono cropping Large plantings of a single species or variety This improves productivity

Pesticides Mono cropping encourages the use of pesticides Pesticide- substance that controls or kills organisms that people consider pests. Insecticides kill insects Herbicides kill weeds Broad-spectrum pesticides- designed to kill many different types of pests. Selective pesticides- designed to kill a narrower range of organisms. Persistent- pesticides that remain in the environment a long time. Nonpersistent- pesticide that breaks down relatively rapidly, usually in weeks to months.

Bioaccumulation An example was DDT. Bioaccumulation- some pesticides are found to build up over time in the fatty tissues of predators. An example was DDT. When an organism containing the pesticide is eaten, the chemical is transferred to the consumer. This eventually leads to very high pesticide concentrations at high trophic levels.

Pesticide Treadmill Resistance- pest populations may evolve resistance to a pesticide over time. Pesticide treadmill- the cycle of pesticide development followed by pest resistance, followed by development of a new pesticide.

Six Ways Agro Ecosystems Differ from Natural Ecosystems Try to stop ecological succession and keep the agroecosystem in an early successional state Monoculture: Large areas planted with a single species Crops are planted in neat rows Farming greatly simplifies biological diversity Plowing is unlike any natural soil disturbance Genetic modification of crops.

Farming Methods Conventional agriculture- industrial agriculture where labor is reduced and machinery is used. Traditional farming- still used in the developing world where human labor is used and not machinery. Shifting agriculture- used in areas with nutrient poor soils. It involves planting an area for a few years until the land is depleted of nutrients and then moving to another area and repeating the process. Nomatic grazing- moving herds of animals to find productive feeding grounds.

Many environmental problems result from agriculture: Soil erosion Sediment transport and deposition downstream On-site pollution from fertilizers and pesticides Deforestation Desertification Degradation of water aquifers Salinization Accumulation of toxic metals and organic compounds Loss of biodiversity

Desertification Desertification is the deterioration of land in arid, semi- arid and dry sub humid areas due to changes in climate and human activities Can be caused by Poor farming practices Conversion of marginal grazing lands to croplands

Where Eroded Soil Goes: Sediments Also Cause Environmental Problems Ways to slow erosion: Making Soil Sustainable Contour Plowing No-Till Agriculture Combination of farming practices that include not plowing the land and using herbicides to keep down weeds.

Sustainable Agriculture Sustainable agriculture- producing enough food to feed the world’s population without destroying the land, polluting the environment, or reducing biodiversity. Intercropping- two or more crop species are planted in the same field at the same time. Crop rotation- rotating crops species from season to season. Agroforestry- intercropping trees with vegetables. Contour plowing- plowing and harvesting parallel to the land to prevent erosion.

Sustainable Agriculture

No Till Agriculture No-till agriculture- helps to stop soil degradation by leaving crop residues in the fields and not tilling the land after each harvest.

Integrated Pest Management Integrated pest management- using a variety of techniques designed to minimize pesticide inputs. Crop rotation Intercropping Planting pest resistant crop varieties Creating habitats for predators Limited use of pesticides

Organic Farming Organic agriculture- production of crops without the use of synthetic pesticides or fertilizers. 3 Qualities It is more like natural ecosystems than monocultures It minimizes negative environmental impacts The food that results from it does not contain artificial compounds

What do you think? Do you(your family) buy organic? Would you buy organic if it was cheaper?

Genetically Modified Food Genetically Modified Crops are modified by genetic engineers to produce higher crop yields and increase resistance to drought, cold, heat, toxins, plant pests and disease.

Benefits of Genetically modified food Increased crop yield Greater food quality Increased profits Increase in nutrition Could reduce the need for pesticides and herbicides Decrease hunger world wide

Concerns about genetically modified food Concerns about safety for humans and the environment Who is testing and researching GMO’s Effects on natural biodiversity Who is regulating When is nature allowed to modify How can we really know when it is safe

The Terminator Gene A genetically modified crop which has a gene to cause the plant to become sterile after the first year This way farmers have to keep buying new seeds but it does not allow for natural processes to take place.

Do you worry about the safety of GMO’s? Discuss- why or why not?

Animal Farming Animals need food too. Rangeland: Provides food for grazing and browsing animals without plowing and planting Pasture: Plowed, planted and harvested to provide forage for animals We also grow food to feed to animals which takes away from the food we need to eat.

High Density Animal Farming CAFOs (concentrated animal feeding operations)- large structures where animals are being raised in high density numbers.

Annual Meat Consumption

White Boards Would you eat less meat if you knew it was damaging the environment? How can we encourage people to eat less meat?

Harvesting of Fish and Shellfish Fishery- a commercially harvestable population of fish within a particular ecological region. Fishery collapse- the decline of a fish population by 90% or more. Bycatch- unintentional catch of non-target species.

Aquaculture Aquaculture Mariculture The farming of food in aquatic habitats Can also cause environmental harm and damage native fish. Can help ocean fish populations by keeping up with food demands. Mariculture The farming of ocean fish Most catfish, salmon, trout, and shrimp are farmed.