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Food and Soil Resources

Food and Soil Resources. G. Tyler Miller’s Living in the Environment 14 th Edition Chapter 14. Key Concepts. Methods of producing food. Increasing food production. Soil degradation. Increasing sustainability. How Is Food Produced?. Sources of food.

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Food and Soil Resources

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  1. Food and Soil Resources G. Tyler Miller’s Living in the Environment 14th Edition Chapter 14

  2. Key Concepts • Methods of producing food • Increasing food production • Soil degradation • Increasing sustainability

  3. How Is Food Produced? • Sources of food • Primary plants: wheat, corn, and rice Wheat, rice, maize, soybeans, barley and sorghum: Production of these crops accounts for more than 40 per cent of the land in the world used for crops, 55 per cent of the non-meat calories in food and more than 70 % of animal feed. • Primary animals:fish, beef, pork, and chicken

  4. Energy Use & Food Production 17% of total US commercial energy used is involved in food production

  5. Major Types of Agriculture • Industrialized agriculture • Plantation • Traditional subsistence agriculture • Traditional intensive agriculture

  6. World Food Production Fig. 14-2 p. 275

  7. Producing Food by Green-Revolution Techniques • High-input monoculture • Selectively bred or genetically-engineered crops • High inputs of fertilizer • Extensive use of pesticides • High inputs of water • Multiple cropping

  8. Green Revolutions Second green revolution (developing countries) First green revolution (developed countries) Major International agricultural research centers and seed banks Fig. 14-4 p. 277

  9. Producing Food by Traditional Techniques • Interplanting • Polyvarietal cultivation • Intercropping • Agroforestry (alley cropping) • Polyculture See Individuals Matter p. 279

  10. Causes of Soil Erosion Wind Water People

  11. Global Soil Erosion Areas of serious concern Areas of some concern Stable or nonvegetative areas Fig. 14-7 p. 280

  12. Soil Erosion in the US Dust Bowl – 1930s: Fig. 14-5 p. 281 Reductions in erosion since 1987 1985 Food Security Act

  13. Causes of Desertification Overgrazing Deforestation Erosion Salinization Soil Compaction Natural Climate Change Refer to Fig. 14-10 p. 283

  14. World Desertification Fig. 14-9 p. 282

  15. Soil Degradation on Irrigated Land Evaporation Evaporation Transpiration Waterlogging Less permeable clay layer • Salinization • Waterlogging Fig. 14-11 p. 283

  16. Reducing and Cleaning Up Salinization Reduce irrigation Switch to salt-tolerant crops Flush soils Not growing crops for 2-5 years Install underground drainage Refer to Fig. 14-12 p. 283

  17. Solutions: Soil Conservation • Conventional-tillage • Conservation tillage • Terracing Refer to Fig. 14-14 p. 285 • Contour farming • Strip and alley cropping • Windbreaks • Land Classification

  18. Soil Restoration • Organic fertilizer • Animal manure • Green manure • Compost • Crop rotation • Commercial inorganic fertilizer

  19. World Food Production • Now leveling off • Shortages in developing countries Fig. 14-16 p. 287

  20. Nutrition • Undernutrition-not enough calories • Malnutrition- “bad” food • Overnutrition-too many calories. • The US spends twice as much on weight loss • each year as it would take to feed the world Refer to Fig. 14-17 p. 288

  21. Environmental Effects of Food Production • Biodiversity loss • Soil degradation See Fig. 14-18 p. 290 • Air pollution • Water shortages and erosion • Human health

  22. Increasing World Crop Production • Crossbreeding and artificial selection • Genetic engineering (gene splicing) • Genetically modified organisms (GMOs) • Continued Green Revolution techniques • Introducing new foods • Working more land

  23. Same spot after 10 years of protection

  24. Producing More Meat Kilograms of grain needed per kilogram of body weight Beef cattle 7 Pigs 4 Chicken 2.2 Fish (catfish or carp) 2 • Feedlots • Rangelands • Efficiency Fig. 14-22 p. 297 • Improved rangeland management • Environmental consequences (Connections p. 295)

  25. Catching and Raising More Fish • Fisheries • Fishing methods (See Fig. 14-24 p. 299) • Overfishing • Commercial extinction • Aquiculture • Fish farming and ranching

  26. Government Agricultural Policy • Artificially low prices • Subsidies • Elimination of price controls • Food aid

  27. Solutions: Sustainable Agriculture • Low-input agriculture • Organic farming See Fig. 14-29 p. 302 • Profitable • Increasing funding for research in sustainable techniques

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