1. Food Resources G. Tyler Miller’s Living in the Environment 13 th Edition Chapter 13 G. Tyler Miller’s Living in the Environment 13 th Edition Chapter 13

2. Key Concepts Methods of producing food Methods of producing food Increasing food production Increasing food production Environmental effects of food production Environmental effects of food production Increasing sustainability Increasing sustainability

3. How Is Food Produced? Sources of foodSources of food – cropland (76%) – rangeland (17%) – ocean fisheries (7%) Primary plantsPrimary plants – wheat, corn, rice Primary animalsPrimary animals – beef, pork, chicken

4. Major Types of Agriculture Traditional AgricultureTraditional Agriculture –Traditional subsistence uses human labor and draft animalsuses human labor and draft animals produce only enough food for a family’s survival.produce only enough food for a family’s survival. –Traditional intensive increased human and draft labor, fertilizer, and waterincreased human and draft labor, fertilizer, and water higher yields producing enough food for their family and to sell for income.higher yields producing enough food for their family and to sell for income.

5. Major Types of Agriculture Industrialized (high input)Industrialized (high input) –uses large quantities of fossil fuel energy, water, commercial fertilizer, and pesticides –produces huge quantities of single crops or livestock (monoculture) PlantationPlantation –growing cash crops on large monoculture plantations –Mostly for sale in developed countries.

6. Industrialized agriculture in developed countries Intensive traditional agriculture in developing countries Land Labor Capital Fossil fuel energy Land Labor Capital Fossil fuel energy

7. Industrialized agriculture Shifting cultivation Plantation agriculture Nomadic herding Intensive traditional agriculture No agriculture World Food Production

8. Challenge to Farmers: Produce More Food! 1.Farm more land 2.Produce higher yields per unit area

9. Green Revolution Refers to dramatically increased agricultural productivity resulting from the introduction of new, high- yielding strains of grain (rice, wheat, and maize) Ongoing since 1950s

10. Producing Food by Green-Revolution Techniques High-input monoculture High-input monoculture Scientifically bred or genetically- engineered crops Scientifically bred or genetically- engineered crops High inputs of fertilizer High inputs of fertilizer Extensive use of pesticides Extensive use of pesticides High inputs of water High inputs of water Increased intensity and frequency of cropping (multiple cropping) Increased intensity and frequency of cropping (multiple cropping)

11. Green Revolutions First green revolution (developed countries) First green revolution (developed countries) Second green revolution (developing countries) Second green revolution (developing countries) Major International agricultural research centers and seed banks Major International agricultural research centers and seed banks 1950- 1970 1967- today

12. Producing Food by Traditional Techniques (Low input agrodiversity) Interplanting - simultaneously growing a variety of crops on the same plot 1)Polyvarietal cultivation –Planting several varieties of the same crop in a plot 2)Intercropping –Two or more different crops are grown at the same time on a plot

13. Producing Food by Traditional Techniques (Low input agrodiversity) 3)Agroforestry (alley cropping) –Crops and trees are planted together 4)Polyculture –Different plants maturing at various times are planted together Less fertilizerLess fertilizer Protection from wind and water erosionProtection from wind and water erosion Little or no insecticidesLittle or no insecticides Insurance against bad weatherInsurance against bad weather

14. Food Production – good news Total World Grain Production 2,000 1,500 1,000 500 0 Grain production (millions of tons) 1950196019701980199020002010 Year Production is increasing!!

15. Food Production – bad news World Grain Production per Capita 400 350 300 250 150 Per capita grain production (kilograms per person) 1950196019701980199020002010 200 Year Population growth outstripped production

16. Human Nutrition MacronutrientsMacronutrients –Protein, carbohydrates, and fats MicronutrientsMicronutrients –Vitamins A, C, and E –Minerals (iron, iodine, and calcium) Undernutrition – consuming insufficient food to meet one’s minimum daily energy needs.

17. Nutrition Malnutrition – faulty nutrition, caused by a diet that does not have enough protein, essential fats, vitamins, minerals and other nutrients needed for good health. MarasmusMarasmus –Diet low in both calories and protein KwashiorkorKwashiorkor –Severe protein deficiency

18. Marasmus – “wasting disease”

19. Kwashiorkor “displaced child”

20. PovertyMalnutrition Decreased resistance to disease High death rate for children Decreased energy Decreased ability to learn Decreased ability to work Shortened life expectancy Feedback loop

21. Environmental Effects of Food Production  Biodiversity loss  Soil  Air pollution  Water  Human health

22. Biodiversity Loss Loss and degradation of habitat from clearing grasslands and forests and draining wetland Fish kills from pesticide runoff Killing of wild predators to protect livestock Loss of genetic diversity from replacing thousands of wild crop strains with a few monoculture strains Soil Erosion Loss of fertility Salinization Waterlogging Desertification

23. Air Pollution Greenhouse gas emissions from fossil Fuel issue Other air pollutants from fossil fuel use Pollution from pesticide sprays Water Aquifer depletion Increased runoff and flooding from land cleared to grow crops Sediment pollution from erosion Fish kills from pesticide runoff Surface and groundwater pollution from pesticides and fertilizers Overfertilization of lakes and slow-moving rivers from runoff of nitrates and phosphates from fertilizers, livestock wastes, and food processing wastes

24. Human Health Nitrates in drinking water Pesticide residues in drinking water, food, and air Contamination of drinking and swimming water with disease organisms from livestock wastes Bacterial contamination of meat

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

27. Crop Cross breeding Desired trait (color) ApplePear Offspring Cross breeding breeding Best results New offspring Desired result Traditional Crossbreeding 1)Slow process 2)Can combine traits only from closely related species

28. Phase 1 Make Modified Gene Identify and extract gene with desired trait Identify and remove portion of DNA with desired trait Remove plasmid from DNA of E. coli Insert extracted DNA (step 2) into plasmid (step3) Insert modified plasmid into E. coli Grow in tissue culture to make copies cell gene DNA Plasmid E. coli DNA Genetically modified plasmid

29. Phase 2 Make Transgenic Cell Transfer plasmid copies to a carrier agrobacterium Agrobacterium inserts foreign DNA into plant cell to yield transgenic cell Transfer plasmid to surface microscopic metal particle Use gene gun to inject DNA into plant cell A. tumefaciens (agrobacterium) Plant cell Nucleus Host DNA Foreign DNA

30. Phase 3 Grow Genetically Engineered Plant Transgenic cell from Phase 2 Cell division of transgenic cells Culture cells to form plantlets Transgenic plants with new traits 1)Half the time as conventional crossbreeding 2)Cuts costs 3)Allows insertion of genes from almost any other organism

31. Increasing World Crop Production Continued Green Revolution techniques?Continued Green Revolution techniques? –Without fertilizer, water, and pesticides green revolution varieties are no more productive than traditional varieties –Green revolution varieties and their needed inputs cost too much for subsistence farming. –Grain yields are increasing at a much slower pace.

32. Increasing World Crop Production Continued Green Revolution techniques?Continued Green Revolution techniques? –Actual gains from green and gene revolutions may be overstated. –Crop yield may start dropping for a number of environmental reasons. –Increased loss of biodiversity can limit genetic raw material.

33. Increasing World Crop Production Introducing new foodsIntroducing new foods –Getting farmers to take risk of growing new types of food. –Getting consumers to try new foods.

34. Increasing World Crop Production Working more landWorking more land Not usable Arid land 6% Tropical forest 8% Cultivated 10% Grazed 11% Forests, arid lands 14% 51% Ice, snow, deserts mountains “Many analysts believe that significant expansion of cropland is unlikely over the next few decades.”

35. How about producing more meat… Rangeland is land that is… –too dry –too steeply sloped –too infertile … to grow crops (40% of ice-free land area) Pastures –managed grasslands or enclosed meadows

36. How is meat produced? Open grazingOpen grazing –80% of cattle, sheep and goats are raised on rangeland Kilograms of grain needed per kilogram of body weight Beef cattle 7 7 Pigs 4 4 Chicken 2.2 Fish (catfish or carp) Fish (catfish or carp) 2 2 FeedlotsFeedlots –Account for 40% of the world’s meat production

37. Producing more meat Condition of the world’s rangelandsCondition of the world’s rangelands –DECLINING! Environmental consequences of meat productionEnvironmental consequences of meat production –See Connections page 299 –Read Spotlight page 300

38. Catching and Raising More Fish Fisheries – concentrations of aquatic species suitable for commercial harvesting in a given body of waterFisheries – concentrations of aquatic species suitable for commercial harvesting in a given body of water 55% of annual commercial catch comes from the ocean.55% of annual commercial catch comes from the ocean. 33% from aquaculture.33% from aquaculture. 12 % from inland freshwater fishing.12 % from inland freshwater fishing.

39. sonar trawl lines float Spotter airplane Fish farming in cage Trawler fishing Purse-seine fishing trawl flap trawl bag Long line fishing lines with hooks Drift-net fishing Fish caught by gills buoy fish school Commercial Fishing Methods

40. Potential to harvest more fish 1950-19821950-1982 +Fish catch increased 5-fold +Per capita seafood catch doubled Since 1982Since 1982 –Little increase in commercial fish catch –Per capita commercial fish catch falling

41. Potential to harvest more fish The primary cause of depletion of fish stocks is too many fishing boats pursuing too few fish or OVERFISHING (Tragedy of the Commons) Habitat destructionHabitat destruction Global warmingGlobal warming

42. Aquaculture Fish farmingFish farming –Cultivating fish in a controlled environment. –Harvesting them when they reach the desired size. –Catfish are the leading aquaculture product in the US

43. Aquaculture ProblemsProblems –Raises demand for ocean fish as fish meal to feed aquaculture species –Creating vast amounts of animal waste in coastal areas –Farming of carnivorous fish increases over-fishing of smaller marine species.

44. Future Increasing wild catch and aquaculture will not increase world food supplies significantly.Increasing wild catch and aquaculture will not increase world food supplies significantly. Fish and shellfish supply only 1% of the energy and 6% of the protein in the human diet.Fish and shellfish supply only 1% of the energy and 6% of the protein in the human diet.

45. Government Agricultural Policy Financially risky businessFinancially risky business Forms of assistance.Forms of assistance. –Keep food prices artificially low. –Give farmers subsides to keep them in business and encourage them to increase food production. –Eliminate price controls and subsides and let farmers and fishers respond to market demand without government control. Increase aid for the poorIncrease aid for the poor

46. Future limitations to increased food production Lack of water for irrigationLack of water for irrigation Reduced genetic diversityReduced genetic diversity Leveling off of yieldsLeveling off of yields Environmental effects which degrade existing croplandEnvironmental effects which degrade existing cropland

47. Solutions: Sustainable Agriculture 1)Slowing population growth 2)Reducing poverty 3)Phasing in systems of sustainable agriculture (also called organic farming)

48. ‘Organic’ foods Plants Produced without synthetic pesticides, fungicides, and herbicides Cannot include genetically engineered foods or be irradiated Cannot be grown on soils fertilized with sewage sludge Animals Produced from 100% organically grown feed. Given access to outdoor range or pasture Produced without use of hormones and antibiotics Animals Produced from 100% organically grown feed. Given access to outdoor range or pasture Produced without use of hormones and antibiotics

49. Principles of Sustainability Most ecosystems use renewable solar energy as the primary source of energy.Most ecosystems use renewable solar energy as the primary source of energy. Ecosystems replenish nutrients and dispose of wastes by recycling chemicals.Ecosystems replenish nutrients and dispose of wastes by recycling chemicals.

50. Principles of Sustainability Biodiversity helps maintain the sustainability of ecological functioning of ecosystems and serves as a source of adaptation to changing environmental conditions.Biodiversity helps maintain the sustainability of ecological functioning of ecosystems and serves as a source of adaptation to changing environmental conditions. In nature there are always limits to population growth and resource consumption.In nature there are always limits to population growth and resource consumption.