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Increasing Yields: The Green Revolution

Increasing Yields: The Green Revolution. Sources:. http://www.lastfirst.net/images/product/R004548.jpg. Yields have increased. British wheat yields tripled in last 50 years 15X increase from 500 years ago Cereal yield worldwide doubled since 1960s. Reasons Yields Increase. Increased inputs

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Increasing Yields: The Green Revolution

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  1. Increasing Yields:The Green Revolution Sources: http://www.lastfirst.net/images/product/R004548.jpg

  2. Yields have increased • British wheat yields tripled in last 50 years • 15X increase from 500 years ago • Cereal yield worldwide doubled since 1960s

  3. Reasons Yields Increase • Increased inputs • Labor • Fertilizer • Machinery • increased output • Using technology • without increasing inputs • Increased efficiency

  4. Production Function • Initially, as input increases, output increases • Eventually, a point of maximum efficiency will be reached • Additional input will lead to diminished increases in output

  5. Inputs • Fertilizer • Can improve yields dramatically: 20-1000% • Diminished response if keep adding • Reduces growth at high levels • Effectiveness depends on • Water/Irrigation • Timing of application • Biggest increase will be in Africa • Dem. Rep. Congo uses 1% fertilizer used in South Africa Cassava in Gambia

  6. Inputs • Animal Traction • 400 million draft animals in world • ½ World’s ag land farmed with draft animals • ¼ farmed with hand tools • ¼ mechanized China

  7. Use of Draft Animals • Do the work of 3-4 humans • Increase land able to be farmed • Animal plowing breaks soil better than by hand • Source of fertilizer • Initial cost high • Profitable if can expand land Vietnam

  8. Tractors • Poorest farmers will consider moving from hand tools to animals • Farmers using animals will consider using machinery • May not be efficient choice: • Credit limited • Gas expensive • Maintenance expensive • But labor cheap Zimbabwe

  9. Big Growers More Efficient? • Are big growers more efficient? • have the know-how to produce • Would redistribution of land would lower production? • hurt the hungry? Brazil Farm

  10. Answer • Big Growers are actually less efficient than small growers in yield/acre • Often land left idle by large landowners (89% in Brazil) • Big operations are fossil fuel intensive requiring 10 Calories for every one produced: NeoCaloric Ag

  11. Answer • Small farmers use labor more intensively • Small farmers use space more efficiently • Small landowners more motivated for production and conservation Tanzania

  12. Big Growers • Advantages of wealth and size • Big farms can more easily survive • Large operations with absentee owners (investors) tend to: • Overuse the soil • Over-spray with chemicals • Remove wealth generated from the community

  13. Land Reform • World Bank: productivity would be increased if land distribution more equitable • Land reform (redistribution) successful after WWII: • South Korea, • Taiwan • China • Recent success • Japan • Zimbabwe • Kerala, India Kerala, India

  14. Green Revolution • 1960’s: improved wheat varieties gave dramatic increase in yield in Mexico • Varieties more responsive to irrigation and petrochemical fertilizers • Soon new rice and maize varieties

  15. Norman Borlaug • Joined Rockefeller Foundation team in Mexico 1944 • Increased yield, rust resistance in wheat • Biggest contributor to Green Revolution • Won Nobel Peace Prize in 1970

  16. Green Revolution • 1970’s: spread to millions of third world farmers • 1990’s: 40% of all farms in third world • 75% Rice in Asia • 80% Wheat in third world • 70% Corn worldwide • Improved standard of living for millions people worldwide

  17. CIMMYT • CIMMYT • International Maize and Wheat Improvement Center • In Mexico • Part of CGIAR • Consultative Group on International Agricultural Research

  18. Criticisms of the Green Revolution • Green Revolution hasn’t alleviated hunger • Economic power, land controlled by few • Technology benefits wealthy • Therefore Green Revolution increases inequity • More hunger AND more food at same time

  19. Criticisms of the Green Revolution • Food Insecurity of poor not addressed • Cash Crops: food flows from the poor and hungry nations to the rich and well-fed nations • Green Revolution not sustainable • destroys resource base on which agriculture depends

  20. Example: India • Self-sufficient in grain due to Green Revolution • But 1/3 of people poor • 5,000 children die each day • Poor cannot afford to BUY the food India

  21. Criticisms of the Green Revolution • Early, poor had little access to credit • Could not buy seeds, fertilizer, irrigation to make Green Revolution work • Wealthy invested, got richer, drove out poor • Now, more emphasis on loans for poor

  22. There are still problems • Need good land (wealthy own) • Agrochemicals bad for health, environment • Expensive inputs: profits to global chemical companies • Rural people displaced from land • Mechanization reduces agricultural jobs • Not ecologically sustainable: depletes soil, pesticide race

  23. Philippines Example • Two villages studied: • large and small farmers invested in Green Revolution • Village 1 had more equal land holdings, solidarity • All benefited from Green Revolution • Village 2 dominated by a few wealthy landowners. • Wealthy increased land by 50% at expense of poor

  24. Farm Squeeze • Fertilizer use increases by huge amount • Yields do not increase proportionally • India: 6x rise in fertilizer use but 2/3 less production/ton fertilizer • Need more fertilizer, pesticide each year for same result • Thus cost go up faster than yields: cost-price squeeze

  25. Farm Squeeze • U.S. true home of Green Revolution • Yields up 3x • but prices down • To survive, must expand acreage • to make up for lower per acre profit.

  26. U.S. Farm Squeeze • Since WWII • number of farms decreased 2/3 • average farm size up ½ • rural communities gutted • production costs up from 50% of gross to 80%

  27. Soil Depletion Worldwide • Dramatic increases in yields during 1970s, 1980s • Soil now depleted, resulting in leveling off or dropping yields • 6% of Ag land in India now useless

  28. Rice • Rice breeding at International Rice Research Institute: IRRI

  29. Rice Problem • 1968: IR8 rice had 2x yield increase • Short • need herbicides to compete with weeds • Uniform genetically • susceptible to pests • Brown plant hopper devastated rice • Insecticide spraying useless • brown hopper resistant

  30. Rice Problem • 1973: IR26 Resistant to brown plant hopper • Worked 2 years • Then Biotype 2 of plant hoppers attacked

  31. Rice Problem • 1975: IR32 Resistant to Biotype 2 • Now Biotype 3 appeared • Insecticides again useless • Insecticides killed off brown hopper predators • Resulted in 40x increase in hoppers

  32. Profits • Profits from Green Revolution go to • Middlemen • Banks • Chemical companies • Biggest growers • Grain prices fall • Farms get bigger Brazil

  33. Increased Dependency • Poor countries must import: • Seeds • Fertilizer • Pesticides • Herbicides • Cost to India increased 600% 1960-1980 • Biotechnology leads to more dependency

  34. Unsustainable Agriculture • Industrial agriculture = • mining land to extract maximum output • “War” between humans and weeds, insects and disease • Market dictates weapons: • pesticides and chemical fertilizers • We are destroying our food- producing resources

  35. Destruction of Ag Resources • Desertification • Soil erosion • Pesticide contamination • Groundwater depletion • Salinization • Urban sprawl • Genetic resources shrinking • Fossil fuels depleting

  36. Sustainable Agriculture Goals • Environmental Health • Economic Profitability • Social and Economic Equity

  37. Agroecology • Sustainable farming based on ecological principles: • Diversity • Interdependence • Synergy • Complex interactions • Science to improve not displace traditional farming • Low energy, capital costs

  38. Agroecology • Intercropping • Mixing annual and perennial crops • Crop rotations • Rotate cereals and legumes • Mixing of plant and animal production • Rice paddies with edible weeds, fish and rice • Not continuous production of one crop

  39. Africa • Fragile soils must be protected • Could mix millet, cattle, and Acacia trees • Trees fix nitrogen, have deep tap roots • Cattle eat tree pods • Plant millet after leaves fall • Could support 2x population in Senegal • Aid agencies instead promoting new seeds, fertilizers, agrochemicals, biotechnology, free trade

  40. Evergreen Revolution • Swaminathan led Green Revolution in India • Agrees cannot maintain crop yields • Problems: • Excessive use of pesticides • Groundwater depletion • Pollution • Monoculture • Therefore, India needs sustainable agriculture • “Evergreen Revolution “ M.S. Swaminathan World Food Prize 1987

  41. Vandana Shiva "Ecological problems arise from applying the engineering paradigm to life." http://myhero.com/myhero/hero.asp?hero=Shiva

  42. Critic of the Green Revolution in India • “The Green Revolution has been a failure. • It has led to reduced genetic diversity, • increased vulnerability to pests, • soil erosion, • water shortages, • reduced soil fertility, • micronutrient deficiencies, • soil contamination… Vandana Shiva

  43. Critic of the Green Revolution in India • “…reduced availability of nutritious food crops for the local population, • the displacement of vast numbers of small farmers form their land, • rural impoverishment and • increased tensions and conflicts. … Vandana Shiva

  44. Critic of the Green Revolution in India • “…The beneficiaries have been • the agrochemical industry, • large petrochemical companies, • manufacturers of agricultural machinery, • dam builders and • large landowners.” -- Vandana Shiva "The Violence of the Green Revolution: Ecological Degradation and Political Conflict in Punjab." The Ecologist, 1991, 21(2):57-60

  45. Genetic Engineering:The Next Green Revolution ? http://www.businessweek.com/1999/99_15/b3624011.htm

  46. Next Green Revolution? • Biotechnology will help developing countries accomplish things that they could never do with conventional plant breeding” • “I believe genetically modified food crops will stop world hunger.” Norman Borlaug Nobel Peace Prize

  47. The Next Green Revolution? • Biotechnology helps farmers produce higher yields on less land. • Technology allows us to have less impact on soil erosion, biodiversity, wildlife, forests, and grasslands • To achieve comparable yields (1950-1999) with old farming methods, would have needed an additional 1.8 Billion hectares of land Norman Borlaug Nobel Peace Prize

  48. Biotechnology Critic • Biotechnology development • Same vision as chemical industry: • Short term goals • Enhanced yields, profit margins • Nature should be dominated and exploited • forced to yield more • Prefer quick solutions • to complex ecological problems • Reductionist thinking about farming • Instead of integrated systems • Agricultural success means • Short term profits • Not long term sustainability -- Jane Rissler, Union of Concerned Scientists

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