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Explore the history and impact of food production, from ancient agricultural practices to modern industrialized farming. Learn about key inventions, major crops, and the Green Revolution's contribution to global food security.
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CHAPTER 12 The Production and Distribution of Food
Introduction to food production Half of the world’s people eat rice High in energy; low in vitamins and other nutrients Vitamin A deficiency: blindness, immune system failure Affects 195 million children Iron deficiency: anemia and immune system failure Causes 100,000 maternal deaths/year Golden rice (GR2): genetically modified rice Added genes allow rice to synthesize beta carotene (used to synthesize vitamin A) and iron
Frankenfoods The golden rice concept has not been welcomed by all It is a genetically modified (GM) crop It contains genes from corn and beans Greenpeace has waged a campaign against golden rice Frankenfoods: foods that contain foreign genes Created in the laboratory Genetic-engineering technology may be needed to feed billions more, with better nutrition Decades of rapid population growth have left millions dependent on imported food or food aid
Successes Humans have done well at putting food on the table World food production doubled in the past 30 years Rising faster than the population The amount of food in developing countries has increased World food trade is a major economic production in many countries More people are overweight than are hungry But will it be possible to feed 10 billion? Reaching the MDG goal of halving the number of hungry is in question
Patterns of food production 12,000 years ago the Neolithic Revolution introduced agriculture and animal husbandry Fostered development of civilization Major crops and animals were established in the first 1,000 years Food exchange and discovery (1450–1700) From the New World: potatoes, maize, beans, squash, tomatoes, pineapples, cocoa From the Orient: rice From Europe: wheat, onions, sugarcane, animals
Modern industrialized agriculture Until 150 years ago, most Americans lived and worked on small farms Supplied a robust and growing nation Farmers used traditional approaches to pests and erosion Crop rotation, multiple crops, animals wastes as fertilizer People left the farm for jobs in cities and towns The Industrial Revolution in the mid-1800s impacted farming
Transformation of traditional agriculture The Industrial Revolution profoundly changed agriculture Three million U.S. farmers feed the nation Plus produce enough for export This revolution increased farming efficiency Farm numbers went from 6.8 million to 2.1 million Farms increased in size fourfold (to 449 acres) Farm jobs account for 15% of the U.S. workforce The U.S. has frequently produced surpluses Other industrialized nations have had this revolution
Components of the agricultural revolution Infrastructure: transformed agriculture Rural electrification, roads, university programs, markets, transportation, loans, extension programs Price and income support subsidies Subsidies favor corporate farms, not poor farmers Machinery: handles every need for working soil Seeding, irrigating, weeding, harvesting Tractors, combiners, handlers, mowers, toppers, etc. Farmers can cultivate far more land Creates a dependency on fossil fuels
More components of the revolution Land under cultivation: U.S. pastureland and crops comprise one-third (987 million acres) of the total land area Since 1960, increased yields and surpluses reduced the need for land conversion Conservation Reserve Program: reimburses farmers for retiring erosion-prone land and planting it with trees or grasses More land will be used to grow corn for ethanol Globally, valuable and fragile forests and wetlands are converted to cropland
Components of the agricultural revolution Fertilizers: increase yields One ton of fertilizer increases grain yields 15–20 tons Current use is higher than ever High demand is tied to high food prices Most increase is in China, India, Brazil Pesticides: control insect and plant pests But pests have become resistant to many pesticides Despite increased use, losses to pests remain constant Pesticide use is decreasing due to health and environmental effects
More components of the revolution Irrigation: occurs on 18% of all cropland It produces 40% of all food Irrigation is still expanding but at a slower pace Problems include groundwater depletion, salinization, and waterlogging High-yielding varieties of plants: plant geneticists have developed new varieties of wheat, corn, and rice Yields double or triple that of traditional varieties Photosynthetic product is diverted to seeds, not stems, leaves, or roots
The Green Revolution The Green Revolution: technologies that resulted in remarkable increases in crop production In 1943, Norman Borlaug and others bred dwarf hybrid wheat with a large head and thick stalk Mexico tripled wheat production Borlaug was awarded the Nobel Peace Prize in 1970 Many other countries increased crop yields Grain production exceeded population growth The Green Revolution has done more than any other single achievement to prevent hunger and malnutrition
Panacea? High-yielding varieties are now used around the world Has decreased deforestation in developing nations The Green Revolution is not a panacea for all difficulties Grains do best on irrigated fields But water shortages are increasing Grains require fertilizer, pesticides, and energy-using mechanized labor It has not eradicate hunger or poverty People can’t afford to buy food There is no safety net
Impacts of the Green Revolution Research now focuses on disease, pests, and climatic stresses The early revolution helped Asia and Latin America Later years mainly helped Africa and the Middle East Without a Green Revolution, yields in developing nations would have been lower Would have led to higher food prices, more cultivated land, increased hunger, and higher infant mortality Sub-Saharan Africa still lags behind in agriculture Due to the dominance of subsistence agriculture
Subsistence agriculture Subsistence farming: developing world farmers use labor-intensive traditional agricultural methods Practiced on marginal land Described as the “silent giant” that feeds most of the world’s poor Subsistence farmers live on small plots of land They raise food for their household They may sell a small cash crop They do not consider themselves poor Subsistence farming is practiced in regions with rapid population growth But is best suited for low population densities
Problems in Africa 67% of people in sub-Saharan Africa depend on agriculture for their livelihood They experience low yields, rapid population growth, poverty, hunger, and high child mortality The World Bank’s World Development Report 2008 states that agriculture carries the potential for lifting rural Africa out of poverty But most rural farmers lack fertilizer and seeds to improve yields Government subsidies in Malawi have doubled yields
Alliance for a Green Revolution Money from wealthy countries allows subsistence farmers to: Improve irrigation, soil health, and markets Grow enough food for their families Produce enough to encourage economic development Subsistence agriculture works well in some areas Slash-and-burn agriculture: involves shifting cultivation within tropical forests Cleared land supports a few years of crops Gradually shifts into agroforestry (tree plantations with ground crops)
Animal farming and its consequences 25% of the world’s croplands feeds domestic animals 70% of U.S. grain goes to animals The livestock economy: one of the most important activities Four billion four-footed animals; 18 billion birds People enjoy eating meat and dairy products In the developed world, animals are raised in confined animal feeding operations (CAFOs) In the developing world, animals are raised on family farms or by subsistence farmers
CAFOs hurt the environment and people Feeding crops to animals causes the same problems as industrialized agriculture Manure in developing countries is used as fertilizer It is wasted in developed countries Manure overwhelms treatment systems and enters water Fish kills, algal growth, and contamination with pathogens Crowded animals allow diseases to spread Even to humans (e.g., avian flu) Salmonella causes $2.5 billion lost/year in the U.S. Heavy antibiotic use causes bacteria to become resistant
Rain forest crunched 58 million acres (23 million hectares) of rain forests in Latin America have been converted to cattle pasture Most land is held by few ranchers with huge spreads Government policies encouraged colonization of land to produce meat for domestic use Cattle production in the Amazon basin has expanded It is now export driven Brazilian beef brings in $1.5 billion/year
Climate change Deforestation and other land use changes in the tropics release 1.6 billion tons/year of CO2 Livestock belching and flatulence release 100 million tons of methane/year Methane is another greenhouse gas Anaerobic decomposition of manure releases 30 million tons of methane/year Methane released by livestock makes up 3% of all gases causing global warming
Good cow Although livestock contribute to the methane problem, they enhance people’s diets and quality of life Heifer Project International distributes livestock, bee hives, fowl, and fish to families Local people oversee the projects Projects improve the environment Recipients must pass livestock offspring to others Animal farming is more sustainable in rural farms in developing countries than CAFOs in developed nations
Biofuels and food production Burning fossil fuels causes climate change Releases CO2 (a greenhouse gas) Biofuel: a renewable fuel made from ethanol and oil derived from crops Can mitigate climate change No new CO2 is released With rising oil prices, biofuel prices are competitive Ethanol: made from corn (in the U.S.) and sugar (Brazil) One-third of U.S. corn is devoted to ethanol production Food prices have risen worldwide
Consequences Critics say ethanol diverts corn from food production The U.S. produces 40% of the world’s corn and 55–60% of the corn on the market Price increases take food away from children Does ethanol production decrease food? Wheat, rice, and soy prices have risen more than corn Land previously planted in soybeans is planted in corn Field corn is used to produce ethanol Only cornstarch is used for ethanol, leaving proteins, vitamins, and fiber to produce food
Factors contributing to high food costs Increased costs of oil for farm machinery and fertilizer China and India are competing for oil Bad weather and poor harvests in Australia A major wheat exporter Rising demand for meat and animal products from emerging economies 30% of increased prices from 2000 to 2007 is due to biofuels Ethanol could be produced from grasses and timber instead of corn
Future prospects for reducing hunger Projections predict grain production to remain the same Will slightly outpace population growth Also predict increased meat consumption in developing countries Developing countries will not be able to meet rising grain demands Most suitable land is already farmed Increases in grain yields are slowing down Many countries can’t afford to pay for grain imports Sub-Saharan Africa will continue to have hunger
Global picture There are only two ways to increase food production: Increase crop yields Grow food crops on land now being used for feedstock crops, biofuels, or cash crops Yields differ because of weather Soil, rainfall, and sunlight limit productivity It is impossible to predict how climate change will affect rainfall patterns Developing countries could lose 334 million acres of farmland due to tropical temperature increases
Less meat and biofuels What is the possibility of switching from feed grain and cash crops to food for people? Feed grain is a buffer against world hunger More people could eat lower on the food chain The trend is in the opposite direction Land could be converted from cash crops to food But land reform and a balance of trade are needed Biofuel production will increase By using marginal land and switching from other crops Less corn will be available for animal feed and exports
A second Green Revolution A Doubly Green Revolution would Be more productive than the first Green Revolution Conserve natural resources and the environment It must repeat the first revolution’s successes Be equitable, sustainable, and environmentally friendly This new revolution is possible through biotechnology and genetic manipulation
From Green Revolution to Gene Revolution Genetic engineering incorporates desired traits into plants and animals Producing transgenic (generically modified [GM]) organisms Genetic research of the Green Revolution used genes that already existed or mutated in a species Genes can now be exchanged among plants, animals, and bacteria This technology can help produce more food But there are concerns about its development and use
The promise The earliest and most common genetically altered crops Pest-resistant cotton Herbicide-resistant corn and soybeans More recent crops include Sorghum resistant to a parasitic plant (witchweed) Insect-resistant corn, potatoes, cotton Rapidly growing trees and salmon Farmers have grown transgenic corn, soybeans, and cotton 282 million acres were planted with bioengineered crops in 2007
Objectives of agricultural biotechnology Stacked products: a crop containing two or more biotech genes Traits directed toward different pests For example, pest resistance plus herbicide tolerance Agricultural technology aims to: Incorporate disease and pest resistance in tropical plants Increase tolerance to drought, salt, etc. Improve the nutritional quality of crops (e.g., golden rice) Produce pharmaceutical products (“pharma crops”)
Environmental benefits of bioengineered crops Reduced pesticide use Crops are already resistant to pests Less erosion No-till cropping Herbicide-resistant crops Less land brought into production Existing agricultural land produces more food
Marker-assisted breeding New technologies improve crops without transgenic traits Marker-assisted breeding: DNA sequencing locates genes of desirable traits in crops or their wild ancestors Plants with these traits are bred with modern crops High-calcium carrots; higher-yield pigeon peas DNA screening of seedlings for the desired genes means plants don’t need to grow to maturity to see if they were transformed This approach does not need special testing or permits It is also cheaper, faster, and less controversial
Problems of genetic engineering: environmental concerns Pests may become resistant to the toxin in pest-resistant transgenic crops The crop loses its advantage Resistance has been found in weeds that infest fields Resistant weeds can spread rapidly Pollen from transgenic crops can spread to natural areas Kills beneficial insects This occurred in monarch butterflies in the lab Genes can spread by pollen to ordinary plants Create “super” weeds
Problems of genetic engineering: safety issues Transgenic crops contain proteins from other organisms This could trigger an allergic reaction in people Brazil nut genes incorporated in soybeans induced an allergic reaction to people allergic to the nuts Antibiotic-resistant genes are put into organisms This could convey resistance to pathogens Antibiotics could become ineffective Plants could produce new substances in response to foreign genes None of these concerns has become evident in the field
Pharma crops Pharmaceuticals are produced by engineering genes for desirable products into crops The U.S. Department of Agriculture (USDA) has given 200 permits for field tests Involving hormones, enzymes, drugs, etc. The Union of Concerned Scientists (UCS) asked the USDA to stop outdoor production of these crops Pharma crops could contaminate other crops Corn that produces pig vaccine was almost used in food So instead, produce pharmaceuticals with noncrop plants
Problems of genetic engineering: access in the developing world Large agricultural-industrial firms developed early genetically modified organisms Profit is their major motive Poor farmers can’t afford to buy the seeds Some noncommercial and donor-funded labs are helping Research in other countries allows farmers access to crops Genetically modified seeds are spreading through “piracy” The UN FAO reports that benefits are still mostly theoretical But millions have benefited from higher yields, etc.
