1. Environmental Problems With Food Production Ch. 12

2. Producing Food Has Major Environmental Impacts Harmful effects of agriculture on – Biodiversity – Soil – Water – Air – Human health

3. Fig. 12-10, p. 289 Natural Capital Degradation Food Production Biodiversity LossSoilWaterAir PollutionHuman Health Loss and degradation of grasslands, forests, and wetlands in cultivated areas Erosion Water waste Emissions of greenhouse gas CO 2 from fossil fuel use Nitrates in drinking water (blue baby) Loss of fertility Aquifer depletion Pesticide residues in drinking water, food, and air Salinization Increased runoff, sediment pollution, and fl ooding from cleared land Emissions of greenhouse gas N 2 O from use of inorganic fertilizers Fish kills from pesticide runoff Waterlogging Contamination of drinking and swimming water from livestock wastes Killing wild predators to protect livestock Desertification Pollution from pesticides and fertilizers Emissions of greenhouse gas methane (CH 4 ) by cattle (mostly belching) Increased acidity Loss of genetic diversity of wild crop strains replaced by monoculture strains Algal blooms and fish kills in lakes and rivers caused by runoff of fertilizers and agricultural wastes Bacterial contamination of meat Other air pollutants from fossil fuel use and pesticide sprays

4. Environmental Problems with Food Production 1. Soil erosion – Movement of soil by wind and water – Natural causes – Human causes Two major harmful effects of soil erosion – Loss of soil fertility – Water pollution

5. Topsoil Erosion on a Farm in Tennessee Fig. 12-11, p. 289

6. Natural Capital Degradation: Gully Erosion in Bolivia Fig. 12-12, p. 290

7. Wind Removes Topsoil in Dry Areas Fig. 12-13, p. 290

8. Natural Capital Degradation: Global Soil Erosion Fig. 12-14, p. 291

9. Environmental Problems with Food Production 2. Desertification Conversion of rangeland or cropland into destertlike land with a drop in agricultural productivity of 10% or more. – Moderate – Severe – Very severe Human agriculture accelerates desertification Effect of global warming on desertification

10. Severe Desertification Fig. 12-15, p. 291

11. Natural Capital Degradation: Desertification of Arid and Semiarid Lands Fig. 12-16, p. 292

12. Environmental Problems with Food Production 3. Salinization Accumulation of salts in the soil – Gradual accumulation of salts in the soil from irrigation water – Lowers crop yields and can even kill plants – Affects 10% of world croplands

13. Natural Capital Degradation: Severe Salinization on Heavily Irrigated Land Fig. 12-17, p. 292

14. Environmental Problems with Food Production 4. Waterlogging – Irrigation water gradually raises water table – Can prevent roots from getting oxygen – Affects 10% of world croplands

15. Environmental Problems with Food Production 5. Habitat Fragmentation Reduction in Biodiversity

16. Environmental Problems with Food Production 6. Climate Change Clearing and burning of forests creates air pollution Agriculture = ¼ of all human generated greenhouse gases

17. Environmental Problems with Food Production 7. Loss of agrobiodiversity Worlds genetic variety of animal and plant species used to provide food. Since 1900 lost ¾ of genetic diversity in agricultural crops