Chapter 14 Agriculture and Food Resources

1. Chapter 14 Agriculture and Food Resources

2. Food Security • Having access to adequate food • Carryover stocks • Leftover grains • Decreasing • 2006: lower grain harvest than previous two years

3. Food Security • Consumption of animal products increasing • Environmental impacts? • China • Produces most wheat • Largest importer of wheat

4. World Food Problems • U.N. Food and Agriculture Organization • 852 million lack adequate food • Developing countries • Undernutrition • Lack of calories • WHO estimate182 million children under 5

5. World Food Problems • Malnutrition • Lack of calories or nutrients • 3 billion worldwide • Overnutrition • Too many calories • Animal saturated fats, sugar, salt • United States

6. Population and World Hunger • 86 countries • Low income • Food deficient • Food insecurity • Chronic hunger • Malnutrition

7. Food Insecurity

8. World Hunger • Causes • Population growth • Unequal food distribution • Poverty • Solutions • Control population • Promote economic development

9. World Grain Production • 1970-2006 • Grain production doubled • Grain per person did not increase

10. Poverty • Most common cause of undernutrition and malnutrition • More common in rural areas • Difficult problem to solve

11. Industrialized Agriculture • Modern agricultural methods • Developed countries • Inputs • Capital • Energy • Chemicals • High yields

12. Subsistence Agriculture • Traditional agricultural methods • Developing countries • Food for family • Inputs • Labor • Land

13. Shifting Cultivation • Subsistence agriculture • Grow crops, then leave land alone • Slash-and-burn agriculture • Clear forest • Grow crops • Soil loses productivity quickly • Supports small populations

14. Nomadic Herding • Subsistence agriculture • Land not suitable for crops • Livestock continually move • Why?

15. Intercropping • Subsistence agriculture • Variety of crops in same field • Polyculture • Plants mature at different times • Different crops harvested throughout the year

16. Agricultural Challenges • Loss of prime farmland • Loss of domesticated varieties • Improving yields • Curbing environmental impacts

17. Loss of Agricultural Land • More than 400,000 acres lost per year in U.S. • Suburban sprawl • Conservation easements • 1996 Farm Bill • Protect farmland • 30+ years

18. Loss of Domestic Varieties • Farmers using fewer varieties of plants and animals • Modern methods • Uniformity • Maximum production • Loss of genetic diversity • Save germplasm • Tissues • May need later

19. Increasing Crop Yields • Food production has increased • Green revolution • Mid-20th century • Modern methods • High-yield varieties • Chemicals

20. High-Yield Varieties • Done with breeding and biotechnology

21. Green Revolution • Benefits • Mexico increased wheat production • Indonesia self-sufficient in rice • Problems • Developing countries dependent on chemicals, machinery • High energy costs • Too many chemicals

22. Increasing Crop Yields • Demand for grains will increase • Can’t increase amount of land • Yields can only increase so much • Genetic engineering could help • Developing countries will need better farming methods

23. Increasing Livestock Yields • Hormones • Promote faster growth • European Union limits imports of hormone-treated beef: why? • Antibiotics • Animals grow larger (4 – 5%) • Resistant bacteria • WHO wants them eliminated • U.S. still using

24. Environmental Impacts • Air, water pollution • Feedlot agriculture is the norm

25. Environmental Impacts • Pesticides • Resistance • Farmers use more • Residues on food • Land degradation • Loss of productivity • Salinization • Habitat fragmentation

26. Environmental Impacts

27. Looking Towards The Future • Food requirements have been met • Environmental problems increasing • More food will be needed • Vicious circle???

28. Sustainable Agriculture • Maintains soil productivity: conservation techniques • Healthy ecological balance • Minimal long-term impacts • Natural fertilizers

29. Sustainable Agriculture • Less chemicals and antibiotics • Water and energy conservation • Diverse crops

30. Sustainable Agriculture • Organic agriculture • No non-natural chemicals • No genetic engineering • View the farm as an agroecosystem • Second green revolution!

31. Genetic Engineering • Move genes from one species to another • Could improve agriculture

32. Potential Benefits of GM Crops • Decrease nutritional deficiencies worldwide: Golden Rice • Decreased use of pesticides • Heartier plants • Feed the world • More productive farm animals • Better animal vaccines

33. Potential Drawbacks of GM Crops • Cross-pollination with native species • Widespread crop failure • Food allergies • Long-term impacts unknown

34. Controlling Agricultural Pests • Pest: interferes with human welfare or activities • Pesticides • Help control pests • Insecticides • Herbicides • Fungicides • Rodenticides

35. Pesticides • Perfect pesticide • Narrow-spectrum • Kills only intended organism • Breaks down rapidly • Stays where applied • Doesn’t exist! • Broad-spectrum • Kills variety of organisms • Many used today

36. Benefits of Pesticides • Quick, effective control • Protect crops • Save lives

37. Problems With Pesticides • Genetic resistance • 520 insect species resistant • 84 weed species resistant • Bioaccumulation • Biomagnification

38. Problems With Pesticides • Affect non-target species • New pests may emerge

39. Problems With Pesticides • Don’t stay put • Pollute water, soil, air • ≈ 14 million in U.S. have drinking water with traces of herbicides

40. Alternatives to Pesticides • Biological controls • Use naturally occurring organisms • Pheromones • Hormones • Genetics • Irradiation

41. Alternatives to Pesticides

42. Integrated Pest Management • Combination of control methods • Keep crop loss to economically tolerable level • Sustainable agriculture • Management vs. eradication • Education critical • On the increase

43. Case Study: DDT and the Bald Eagle • 1963: 417 pairs left in lower 48 states • Three reasons the population dropped?

44. Case Study: DDT and the Bald Eagle • 1972: DDT banned • Bald Eagle Protection Act • Endangered Species Act • Conservation efforts • 2007: more than 7000 nesting pairs in lower 48 • Removed from Threatened List