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Food Resources. G. Tyler Miller’s Living in the Environment 13 th Edition Chapter 13. Dr. Richard Clements Chattanooga State Technical Community College. Key Concepts. Methods of producing food. Increasing food production. Environmental effects of food production.
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Food Resources G. Tyler Miller’s Living in the Environment 13th Edition Chapter 13 Dr. Richard Clements Chattanooga State Technical Community College
Key Concepts • Methods of producing food • Increasing food production • Environmental effects of food production • Increasing sustainability
How Is Food Produced? • Sources of food • Primary plants:wheat, corn, and rice • Primary animals:beef, pork, and chicken
Major Types of Agriculture • Traditional subsistence • Traditional intensive • Plantation • Industrialized (high-input) See Fig. 13-3 p. 280
World Food Production Plantation agriculture Industrialized agriculture Nomadic herding Shifting cultivation Intensive traditional agriculture No agriculture Fig. 13-2 p. 279
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 • Increased intensity and frequency of cropping
Green Revolutions Second green revolution (developing countries) First green revolution (developed countries) Major International agricultural research centers and seed banks Fig. 13-6 p. 282
Producing Food by Traditional Techniques • Intercropping • Polyvarietal cultivation • Agroforestry (alley cropping) • Polyculture –like a home garden
Food Production • Rapidly increasing • Prices decreasing • Shortages in developing countries • Approaching limits on meat production
Nutrition • Undernutrition • Malnutrition • Overnutrition Refer to Fig. 13-11 p. 286 Refer to Solutions p. 289
Environmental Effects of Food Production • Biodiversity loss • Soil See Fig. 13-13 p. 288 • Air pollution • Water • Human health
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 See Fig. 13-16 p. 291
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 • Rangeland • Pasture • Efficiency Fig. 13-25 p. 298 • Adaptations of rangeland plants • Range condition and management • Environmental consequences (Connections p. 299)
Farm Water Use • Drip • Center Pivot • Sprinkler
Catching and Raising More Fish • Fisheries • Fishing methods (See Fig. 13-30 p. 303) • Sustainable yield • Overfishing • Commercial extinction • Aquiculture • Fish farming and ranching
Aquaculture • Farms (marine cages) –raise and cultivate fish and harvest when reach desired age or size. • Ranch –raise juveniles, then release to grow to adulthood in wild waters, then recapture when return to spawn (ex: salmon) *farm raised vs wild caught. (uncommon)
Government Agricultural Policy • Artificially low prices • Subsidies • Elimination of price controls • Food aid
Solutions: Sustainable Agriculture • Low-input agriculture • Organic farming See Fig. 13-36 p. 308 • More benefits to the poor • Increasing funding for research in sustainable techniques
Solutions: Soil Conservation • Conventional-tillage • All topsoil is turned under and exposed • to erosion and the elements. • Conservation tillage • Minimum or no-till –either loosely break • the surface or use special planting equipment • to put seeds into earth without exposing • topsoil. Refer to Fig. 10-26 p. 224
Solutions Cont.d • Cropping methods • Strip • Contour • Terrace
Windbreaks • Land Classification
Soil Restoration • Organic fertilizer • Animal manure • Green manure • Compost • Crop rotation • Commercial inorganic fertilizer
Soil Conservation 1985 Farm Act – strategy to reduce soil erosion in the US Reduce erosion & restore fertile land Conservation tilling – disturb soil as little as possible Terracing – reduce erosion on slopes Contour farming – plant along contours of gentle slopes Strip cropping – planting alternate strips of crops Alley cropping – planting between shrubs and trees Wind breaks – planting a row of trees or shrubs on perimeters Gully reclamation – fast growing vines and shrubs