Chapter 19 Food Resources: A Challenge For Agriculture

Overview of Chapter 19 o o Food and Nutrition o o World Food Problems o o Principle Types of Agriculture o o Challenges of Producing More Crops and Livestock o o Environmental Impact of Agriculture o o Solutions to Agricultural Problems o o Fisheries of the World

Food and Nutrition o o Carbohydrates Sugars and starches metabolized by cellular respiration to produce energy o o Proteins Large, complex molecules composed of amino acids that perform critical roles in body o o Lipids Include fats and oils and are metabolized by cellular respiration to produce energy o o Vitamins and Minerals

Human Foods

World Food Problems o o Feeding growing population is difficult o o Annual grain production (left) has increased since 1970 o o Grain per person has not (right)

World Food Problems o o Famine Failure of crops caused by drought, flood or catastrophic event Temporary but severe shortage of food o o Maintaining World Grain Carryover Stockpiles Amounts of rice, wheat, corn and other grains remaining from previous harvest Provides measure of food security Decreased each year since 1987 UN feels carryover stock should not fall below 70 days

World Grain Carryover Stock o o Why the decline? Rising temperatures Falling water tables and droughts Ethanol production More grain is going towards feeding livestock

World Food Problems Already read in text book that major food-producing countries produce enough grain to feed the rest of the world. So why are people hungry? Poverty billion people are so poor they cannot afford proper nutrition poverty increasing in developing countries rural areas poorer than urban areas infants, children and the elderly most at risk unequal distribution of available food supplies loss of or decline in arable land increasing rate of population growth population growth control would ease food related problems (more in next unit)

World Food Problems o o Economics costs money to produce, store, transport, and distribute food countries (usu. developing countries) with the greatest need for food cannot afford to pay for it food-producing nations (usu. developed countries) cannot afford to give it away o o Politics corruption, greed, power o o Developing countries need to become agriculturally self-sufficient

Principle Types of Agriculture o o Industrialized Agriculture relies on high inputs of capital ($) and energy requires less land and labor produces high yields through monoculture land degradation air pollution – use of fossil fuels and pesticides surface water and groundwater pollution by manure from CAFOs (livestock factories) eutrophication - fertilizer enrichment of surface water pesticide resistance in many insect, weeds, and disease-causing organisms habitat fragmentation by clearing grasslands & forests, and draining wetlands to grow crops

Principle Types of Agriculture o o Subsistence Agriculture Traditional agricultural methods, which are dependent on labor and large amounts of land o o Examples: Shifting cultivation Slash and burn agriculture Nomadic herding Intercropping

Principle Types of Agriculture o o Sustainable Agriculture alternative or low-input agriculture combination of methods best suited to problems maintain soil fertility – crop rotation (nitrogen) control soil erosion - conservation tillage, and contour plowing increase biological diversity organic fertilizers - compost and manure conserve of water and energy

Principle Types of Agriculture o o Sustainable Agriculture (cont.) integrated pest management (IPM) natural predator-prey relationships to control pests limited use of pesticides only when necessary

Solutions to Agricultural Problems- Sustainable Agriculture

Challenges of Producing More Crop and Livestock o o Domestication and Genetic Diversity Domestication of crops and livestock Farmer selects and propagates animals with desirable agricultural characteristics Benefit: development of high yielding crops or high producing livestock (meat and milk) Drawback: loss of genetic diversity - Many high yielding crops are genetically uniform High likelihood that if bacteria, fungi, viruses, etc. attack, will destroy entire crop. Why?

o Increasing Crop Yield Challenges of Producing More Crop and Livestock Food production increased in developed countries (wheat (left) Pesticides Selective breeding

Case-In-Point Green Revolution Increasing Crop Yields What was the green revolution? o o using modern cultivation methods, such as inorganic chemical fertilizer and pesticides, and the high-yielding varieties of certain staple crops to produce more food per acre of cropland o o Selective Breeding

Case-In-Point Green Revolution High Yielding Rice Varieties

o o Increasing Livestock Yields Hormone supplements US and Canada do this Europe does not citing human health concerns Antibiotics 40% of antibiotics produced in US are used in livestock operations Problems with increased bacteria resistance Challenges of Producing More Crop and Livestock

Antibiotic Use and Resistance

o o Manipulation of genes by taking specific gene from a cell of one species and placing it into the cell of an unrelated species Genetic Engineering

Issue with Genetically Modified Organisms (GMOs) o o Determined to be safe for human consumption o o Concerns about GMO seed or pollen spreading in wild o o Backlash against GMOs o o GMOs are not currently labeled FDA finds it would be counterproductive and expensive to label

Environmental Impacts of Agriculture o o High use of fossil fuels and pesticides Air pollution o o Untreated animal wastes and agricultural chemicals Water pollution Harms fisheries o o Insects, weeds, and disease- causing organisms developing resistance to pesticides Contaminate food supply

Environmental Impact of all kinds of Agriculture o o Land degradation Decreases future ability of land to support crops or livestock o o Habitat fragmentation Breakup of large areas of habitat into small, isolated patches o o Cultivating marginal lands Irrigating dry land Cultivating land prone to erosion

Fisheries of the World- Problems o o No nation lays claim to open ocean Resource susceptible to overuse and degradation Tragedy of the Commons o o Overharvesting Many species are at point of severe depletion Cod (right) 62% of world’s fish stock are in need of management action

Fisheries of the World- Problems o o Overharvesting due to sophisticated fishing equipment o o Bycatch killed off because often illegal to take from ocean

Fisheries of the World- Problems o o Ocean Pollution – degradation of marine environments oceans used as dumping grounds old saying: “dilution is the solution to pollution” oil heavy metals (such as …) litter - deliberate dumping stormwater runoff from cities and agricultural areas

Fisheries of the World- Problems o o Aquaculture growing of aquatic organisms for human consumption both fresh and marine waters great potential to supply food locations of fisheries may degrade natural habitats produce waste that pollutes adjacent water use of antibiotics in feed spread of disease and sea lice due to close quarters

Aquaculture