Food, Soil, and Pest Management

1. Chapter 12 Food, Soil, and Pest Management

2. We can sharply cut pesticide use without decreasing crop yields by using a mix of cultivation techniques, biological pest controls, and small amounts of selected chemical pesticides as a last resort (integrated pest management). How Can We Protect Crops from Pests More Sustainably?

3. What is a pest – interferes with human welfare • Natural enemies—predators, parasites, disease organisms—control pests • In natural ecosystems • In many polyculture • agroecosystems Nature Controls the Populations of Most Pests

4. Pesticides • Insecticides – insects killers • Herbicides – weed killers • Fungicides – fungus killers • Rodenticides – rat and mouse killers • Herbivores overcome plant defenses through natural selection: coevolution We Use Pesticides to Try to Control Pest Populations

5. First-generation pesticides-natural chemicals from plants • Second-generation pesticides • Paul Muller: DDT Nobel Prize 1948 • Benefits versus harm • Broad-spectrum agents – toxic to many pests and non-pest species. Chlorinated hydrocarbons: DDT, organophosphates : malathion, parathion • Selective or narrow spectrum agents - • Persistence – length of time they remain deadly in the environment for years, biologically magnified in food webs We Use Pesticides to Try to Control Pest Populations

6. Biologist : DDT use was increasing to control mosquitoes Silent Spring - 1962 Potential threats of uncontrolled use of pesticides Gave impetus to the US environmental movement Individuals Matter: Rachel Carson

7. Save human lives prevented deaths from malaria, typhus and bubonic plague : at least 7 million people • Increases food supplies and profits for farmers protect 55% of the world’s food supply. Profit $1:$4 • Work quickly, long shelf life, easily shipped and applied • Health risks are very low relative to their benefits • New pest control methods: safer and more effective Modern Synthetic Pesticides Have Several Advantages

8. Accelerate the development of genetic resistance, 5 to 10 years, sooner in the tropics Financial treadmill Kill natural predators and parasites that help control Only 0.1-2% of the pesticide applied by aerial or ground spraying reaches the target pest. Rest pollutes air, water, harm wild life, affect human health Expensive for farmers Some insecticides kill natural predators and parasites that help control the pest population Pollution in the environment Some harm wildlife Some are human health hazards Modern Synthetic Pesticides Have Several Disadvantages

9. David Pimentel: Pesticide use has not reduced U.S. crop loss to pests • Loss of crops is about 31%, even with 33-fold increase in pesticide use • High environmental, health, and social costs with use, $5-10 in damages for every $1 spent • Use alternative pest management practices could halve the use of chemical pesticides on 40 major US crops • Pesticide industry refutes these findings • Campbell soup tomatoes in Mexico, Rice in Indonesia, Sweden Modern Synthetic Pesticides Have Several Disadvantages

10. Best-selling herbicide (Roundup), Monsanto Advantages – does not harm living things, degrades into harmless substances within weeks Disadvantages - resistant weeds , expensive to develop other pesticides Glyphosate-Resistant Crop Weed Management System: A Dilemma

12. 1955: Dieldrin sprayed to control mosquitoes • Malaria was controlled • Dieldrin didn’t leave the food chain • Domino effect of the spraying • Happy ending Case Study: Ecological Surprises

13. U.S. federal agencies • EPA • USDA • FDA • Effects of active and inactive pesticide ingredients are poorly documented • Circle of poison, boomerang effect – residues of banned chemicals exported to other countries may come back on food, winds carry persistent pesticides such as DDT Laws and Treaties Can Help to Protect Us from the Harmful Effects of Pesticides

14. 1998 – 50 countries developed treaty that requires exporting countries to have consent from importing countries for exports of 22 pesticides , 5 industrial chemicals 2000 – 100 countries signed to phase out 12 of the most hazardous persistent organic pollutants (POP’s), 9 of them hydrocarbons (DDT) United States has not signed this agreement International Treaties

15. Fool the pest : rotate crops, adjust plant times Provide homes for pest enemies Implant genetic resistance : GMO’s Bring in natural enemies : natural predators Use insect perfumes Hormones Scald them Alternatives to Using Pesticides

16. Integrated pest management (IPM) • Coordinate: cultivation, biological controls, and chemical tools to reduce crop damage to an economically tolerable level • Disadvantages • expert knowledge Integrated Pest Management Is a Component of Sustainable Agriculture

17. Control prices – keep artificially low • Provide subsidies – price supports, tax breaks, subsidies for 31% of global farm income • Developed : $280 billion /year • Substitute traditional subsidies with ones that promote sustainable farming practices • Subsidies to fishing – promotes destructive fishing practices • Let the marketplace decide Use Government Policies to Improve Food Production and Security

18. United Nations Children’s Fund (UNICEF) suggests these measures. Can be done at an average annual cost of $5-10 / child • Immunizing children against childhood diseases • Encourage breast-feeding • Prevent dehydration in infants and children • Prevent blindness – Vitamin A capsule (75c/child) • Provide family planning services • Increase education for women Use Government Policies to Improve Food Production and Security

19. Sustainable food production will require reducing topsoil erosion, eliminating overgrazing and overfishing, irrigating more efficiently, using integrated pest management, promoting agrobiodiversity, and providing government subsidies for more sustainable farming, fishing, and aquaculture. How Can We Produce Food More Sustainably?

20. Producing enough food to feed the rapidly growing human population will require growing crops in a mix of monocultures and poly cultures and decreasing the enormous environmental impacts of industrialized food production. How Can We Produce Food More Sustainably?

21. Soil conservation, some methods • Terracing • Contour planting • Strip cropping with cover crop • Alley cropping, agroforestry • Windbreaks orshelterbeds • Conservation-tillage farming • No-till • Minimum tillage • Identify erosion hotspots Reduce Soil Erosion

22. Solutions: Mixture of Monoculture Crops Planted in Strips on a Farm

23. Organic fertilizer • Animal manure – dung , urine • Green manure – freshly cut, growing green vegetation • Compost microorganisms to break down organic waste • Commercial inorganic fertilizer active ingredients • Nitrogen • Phosphorous • Potassium Crop Rotation Restore Soil Fertility

24. Soil salinization • Prevention • Clean-up • Desertification, reduce • Population growth • Overgrazing • Deforestation • Destructive forms of planting, irrigation, and mining Reduce Soil Salinization and Desertification Flush soil (expensive and wastes water Reduce irrigation Stop growing crops for 2–5 years Switch to salt-tolerant crops (such as barley, cotton, and sugar beet Install underground drainage systems (expensive)

25. Paul Mader and David Dubois • 22-year study • Compared organic and conventional farming • Benefits of organic farming • little or no use of synthetic pesticides, fertilizers or genetically engineered seeds, fields free for 3 years • livestock raised without genetic engineering Shift to More Sustainable Agriculture

26. SOLUTIONS Organic Farming Improves soil fertility Reduces soil erosion Retains more water in soil during drought years Uses about 30% less energy per unit of yield Lowers CO2 emissions Reduces water pollution by recycling livestock wastes Eliminates pollution from pesticides Increases biodiversity above and below ground Benefits wildlife such as birds and bats Fig. 12-32, p. 308

27. Effect of different fertilizers on nitrate leaching in apple trees • calcium nitrate and alfalfa residues, composted chicken manure, integrated approach (combined) • Less nitrate leached into the soil after organic fertilizers were used – 4.4 to 5.6 times less Scientists Are Studying Benefits and Costs of Organic Farming

28. Comparison of the Roots between an Annual Plant and a Perennial Plant Roots of a tall grass prairie plant Annual Wheat Crop Plant Better at using water and nutrients

29. Supports local economies Does not have to be transported far – reduces greenhouse gas emissions, 5 to 17 times less Reduces environmental impact on food production – grow organic food or buy organic food grown locally Community-supported agriculture (CSA) Buy Locally Grown Food ……………………