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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. Two Worlds. Soil, a limited resource we depend upon, but take for granted. Chapter 14: Key Concepts. Methods of producing food. Increasing food production. Soil degradation.

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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. Two Worlds

  3. Soil, a limited resource we depend upon, but take for granted

  4. Chapter 14: Key Concepts • Methods of producing food • Increasing food production • Soil degradation • Increasing sustainability

  5. Aldo Leopold There are two spiritual dangers in not owning a farm. One is the danger of supposing that breakfast comes from the grocery store, and the other that heat from the furnace.

  6. Section 1: How Is Food Produced? What systems provide us with food? What plants and animals feed the world? What are the major types of food production?

  7. How Food Is Produced Historically: • Croplands (77%) • Rangeland (16%) • Ocean Fisheries (7%) Since 1950 there has been a staggering increase in all production. Huge technology increase

  8. How Food Is Produced Technology Changes: Farm machinery Fishing equipment Fertilizers Pesticides Irrigation GE Foods Feedlots Fish farms Each improvement brings new challenges

  9. How Food Is Produced Can we meet the challenge of feeding 9 billion people by 2050? • W/O Degradation of environment • And reduce poverty (1 of 5 do not produce enough food)

  10. How Food Is Produced • 30,000 possible plant species people can eat • Since ag. rev. 10,000 consumed • Today: 14 plants, 8 terrestrial animals provide 90% calories • 3 (wheat, rice and corn) provide ½ world’s calories – all annuals (potatoes huge also) • Dramatic reduction in biodiversity of agriculture • Most cannot afford meat

  11. How Is Food Produced? • Sources of food • 3 Primary plants:wheat, corn, and rice • 4 Primary animals:fish, beef, pork, and chicken

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

  13. Major Types of Agriculture Industrial Agriculture: • Fossil Fuel Energy • Heavy Water Use • Single Crops (monoculture) • Commercial fertilizers • ¼ of all cropland • Mostly in developed countries

  14. Industrial agriculture in California

  15. Major Types of Agriculture Plantation Agriculture: • Form of industrial agriculture in tropical developing countries • Cash crops: banana, coffee, sugar cane, cocoa • Monoculture for sale in developed countries • Increasing large livestock Coffee Plantation

  16. Major Types of Agriculture Traditional Subsistence Agriculture: • Human labor and draft animals producing food form family survival • Nomadic herding • 42% of world’s people uses traditional agriculture

  17. Major Types of Agriculture Traditional Intensive Agriculture: • Increasing human and animal labor, fertilizers, water to get higher yields • Enough food for family and to sell locally • Agriculture is world’s leading industry

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

  19. Hunterdon County, New Jersey

  20. Section 2: 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

  21. Green Revolution in Agriculture Since the 1950s farmers having been getting huge increases in crop production per unit of land. First Step: develop and plant monocultures of GM high-yield crops like corn, rice and wheat Cavendish Banana

  22. Green Revolution in Agriculture Second Step: Use large inputs of fertilizers, pesticides and water. Third Step: Increase number of crops grown per year on a plot of land (more crop less land) These techniques produce huge increases in crops BUT need lots of water, fossil fuels, machinery, pesticides, fertilizers * Uses 8% of world’s oil *

  23. Green Revolution in U.S. Agribusiness: loss of the family farm to corporate farming…Superfarms • U.S. Ag. More total sales than auto, steel and housing combined • 18% of Gross National Income (1/5 of all U.S. private sector jobs) • 0.3% of world’s farmers produce 17% of world’s grain (1/2 of world’s corn and soybeans) • Huge increase in efficiency

  24. Green Revolution in U.S. Developed Countries: People spend about 40% of income on food Developing Countries: 70% Industrial Ag. Needs cheap fossil fuels…putting food on table accounts for 17% of energy used in U.S. Energy used to grow, store, process, package, transport, refrigerate, cook 10 units of energy for 1 unit of food energy in your stomach

  25. 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

  26. Producing Food by Traditional Techniques • Interplanting • Polyvarietal cultivation • Intercropping • Agroforestry (alley cropping) • Polyculture Look up terms on page 278

  27. Showing where energy is used in food production in U.S. Food travels avg. of 1,500 miles from farm to fork in U.S.

  28. New Jersey Peach Farm: What are the advantages and disadvantages of eating locally grown food?

  29. Section 3: Soil Erosion What causes soil erosion? How serious of a problem is it? Good news and bad news from the U.S. What is desertification? How do salts degrade the soil?

  30. Causes of Soil Erosion Wind Water #1 People Why care about soil erosion?

  31. Impacts of Soil Erosion • Loss of soil fertility • Sediment runoff causes problems in surface water (pollution, clog ditches, boat channels, reservoirs) • #1 source of U.S. water pollution • Renewable only on LONG timeframes (200-1,000yrs. for 1 inch)

  32. Soil Erosion On Ag. land in U.S. today, soil is eroding 16 times faster than it is created

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

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

  35. Huge Erosion Problems During “Dust Bowl” era

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

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

  38. Desertification: causes and consequences. • Occurring on 1/3 of world’s land

  39. Salinization • Irrigation water contains small amounts of dissolved salts • Evaporation and transpiration leave salts behind • Salt builds up on soil

  40. 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

  41. Soil Degradation on Irrigated Land Evaporation Evaporation Transpiration Waterlogging Less permeable clay layer • Salinization • Waterlogging • Precipitation and irrigation water percolate downward • Water table rises • Bad for roots Fig. 14-11 p. 283

  42. Section 4: Soil Conservation What is soil conservation and how does it work? What are some methods for reducing soil erosion? Inorganic versus organic fertilizers

  43. Soil Conservation Involves many ways of reducing soil erosion and restoring fertility to soil.

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