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Food, Soil, and Pest Management. Chapter 12. Core Case Study: Grains of Hope or an Illusion?. Vitamin A deficiency in some developing countries leads to Blindness Death 1999: Porrykus and Beyer Genetically engineered rice with beta-carotene and more iron
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Food, Soil, and Pest Management Chapter 12
Core Case Study: Grains of Hope or an Illusion? • Vitamin A deficiency in some developing countries leads to • Blindness • Death • 1999: Porrykus and Beyer • Genetically engineered rice with beta-carotene and more iron • Is this the answer for malnutrition in these countries? • Challenge of increased food production • ~225,000People born each day
Golden Rice: Genetically Engineered Strain of Rice Containing Beta-Carotene
12-1 What Is Food Security and Why Is It Difficult to Attain? • Concept 12-1A Many of the poor suffer health problems from chronic lack of food and poor nutrition, while many people in developed countries have health problems from eating too much food. • Concept 12-1B The greatest obstacles to providing enough food for everyone are poverty, political upheaval, corruption, war, and the harmful environmental effects of food production.
Many of the Poor Have Health Problems Because They Do Not Get Enough to Eat • Food security: every person in a given area has daily access to enough nutritious food to have an active & healthy life • Food insecurity: living with chronic hunger & poor nutrition which threatens their ability to lead healthy & productive lives • Root cause: poverty • Prevents them from growing or buying enough food • Leads to political upheaval corruption, & war which interferes with food distribution & transportation
Many People Suffer from Chronic Hunger and Malnutrition (1) • Macronutrients • Carbohydrates • Proteins • Fats • Micronutrients • Vitamins: A, C, C • Minerals: iron, iodine, & Ca
Many People Suffer from Chronic Hunger and Malnutrition (2) • Chronic undernutrition, hunger • Face mental retardation, stunted growth & death from infectious diseases • Chronic malnutrition: deficiencies of protein or other key nutrients • Poor live on low protein, high carbohydrate, vegetarian diet: wheat, rice, or corn • What progress in being made? • Undernourished or malnourished has fallen between 1970-2006 • But corn is going to ethanol rather than food
Many People Do No Get Enough Vitamins and Minerals • Most often vitamin and mineral deficiencies in people in developing countries • Iron: component of hemoglobin transports oxygen to blood lack of it causes anemia: causes fatigue, increased infection, increased chance of death at childbirth • Vitamin A: golden rice, DNA from daffodil • Iodine: thyroid gland: metabolism, chronic lack cause stunted growth, mental retardation & goiter
Acute Food Shortages Can Lead to Famines • Famine: severe shortage of food in an area accompanied by mass starvation, leads to death, economic chaos, & social disruption • Usually caused by crop failures from • Drought • Flooding • War • Other catastrophic events
War and the Environment: Starving Children in Famine-Stricken Sudan, Africa
Many People Have Health Problems from Eating Too Much • Overnutrition: food energy intake exceeds energy use & causes excess body fat • Similar health problems to those who are underfed • Lower life expectancy • Greater susceptibility to disease and illness • Lower productivity and life quality
12-2 How Is Food Produced? • Concept 12-2A We have sharply increased crop production using a mix of industrialized and traditional agriculture. • Concept 12-2B We have used industrialized and traditional methods to greatly increase supplies of meat, fish, and shellfish.
Food Production Has Increased Dramatically • Three systems produce most of our food • Croplands: 77% • Rangelands, pastures, and feedlots: 16% • Aquaculture: 7% • Importance of wheat, rice, and corn: 47% of calories, 42% of protein • Estimated that there are 50,000 plant species that people can eat, only 14 supply most of the world’s food • Tremendous increase in global food production • Since 1960: Technological advances, inorganic chemical fertilizers, irrigation, pesticides, high-yield grain, large #’s of livestock, poultry, fish in factory like conditions
Industrialized Crop Production Relies on High-Input Monocultures • Industrialized agriculture, high-input agriculture: uses heavy equipment & large amounts of financial capital • Goal is to steadily increase crop yield • Plantation agriculture: cash crops (bananas, soy beans, sugar cane, coffee usually for export to developed countries)
Industrialized Agriculture Continued • Greenhouses: used to raise crops along arid land • Hydroponics: plants grow in troughs of water, water is pumped from troughs and sprayed on plants as artificial rain
Satellite Images of Greenhouse Land Used in the Production of Food Crops
Traditional Agriculture Often Relies on Low-Input Polycultures • Traditional subsistence agriculture: human labor & draft animals to produce only enough for the family • Traditional intensive agriculture: farmers increase inputs of human labor, fertilizer & water to obtain higher crop yields • Polyculture • Benefits over monoculture: protection from pests, higher yields • Slash-and-burn agriculture: clearing small plots in tropical forests, grow a variety of crops for a few years until soil is depeleted & move to other plots
Science Focus: Soil Is the Base of Life on Land • Soil composition: rock, mineral, decaying organic matter, water, air, billions of living organisms • Soil formation: bedrock broken down by physical chemical, & biological processes (weathering) • Layers (horizons) of mature soils • O horizon: leaf litter • A horizon: topsoil • B horizon: subsoil • C horizon: parent material, often bedrock • Soil erosion: concern is the A horizon
Wood sorrel Oak tree Earthworm Organic debris builds up Millipede Grasses and small shrubs Rock fragments Mole Honey fungus Moss and lichen Fern O horizon Leaf litter A horizon Topsoil Bedrock B horizon Subsoil Immature soil Young soil C horizon Parent material Mite Nematode Root system Red earth mite Fungus Mature soil Bacteria Fig. 12-A, p. 281
A Closer Look at Industrialized Crop Production • Green Revolution: increase crop yields: since 1950 • 1. Monocultures of high-yield key crops • E.g., rice, wheat, and corn • 2. Use large amounts of fertilizers, pesticides, and water • 3. Multiple cropping • Second Green Revolution: Since 1967, Introduced fast growing varieties of rice & wheat for tropical climates • World grain has tripled in production
Global Outlook: Total Worldwide Grain Production (Wheat, Corn, and Rice)
Case Study: Industrialized Food Production in the United States • Agribusiness: small number of giant multi-national corporations increasingly control the growing, processing, distribution, & sale of food in the U.S. & globally • Annual sales: Total is bigger than the country’s automotive, steel, & housing combined • Food production: very efficient • Since 1950 more that doubled the yield-has kept large areas of forests, grasslands, & wetlands from being converted • Percent of income spent on food • U.S. 2% • Developing Countries 40% • Poorest 70%
Crossbreeding and Genetic Engineering Can Produce New Crop Varieties (1) • Gene Revolution • Cross-breeding throughartificial selection • Slow process: 15 years or more to produce a commercially valuable new crop variety • Remains useful for 5-10 years before pests & disease reduce their effectiveness • Genetic engineering • Genetic modified organisms (GMOs) or transgenic organisms: Improved strains of crops & livestock animals
Crossbreeding and Genetic Engineering Can Produce New Crop Varieties (2) • Age of Genetic Engineering: developing crops that are resistant to • Heat and cold • Herbicides • Insect pests • Parasites • Viral diseases • Drought • Salty or acidic soil • Advanced tissue culture techniques: • Ex. Mass produce only orange juice sacs which
Meat Production and Consumption Have Grown Steadily • Animals for meat raised in • Pastures • Feedlots & confined animal feeding operations that are fed grain or meal produced from fish • Meat production increased fourfold between 1961 and 2007 • Demand is expected to go higher: likely to double by 2050 as affluence rises, more land goes to feeding the livestock
Fish and Shellfish Production Have Increased Dramatically • Aquaculture, blue revolution: raising marine & freshwater fish in ponds & underwater cages • World’s fastest-growing type of food production • Dominated by operations that raise herbivorous species • Polyaquaculture: • Ex. integrating crop growing & aquaculture by using rice straw, pig & duck manure & other agricultural wastes to fertilize farm ponds & rice paddies to produce phytoplankton eaten by carp
12-3 What Environmental Problems Arise from Food Production? • Concept 12-3 Food production in the future may be limited by its serious environmental impacts, including soil erosion and degradation, desertification, water and air pollution, greenhouse gas emissions, and degradation and destruction of biodiversity.
Producing Food Has Major Environmental Impacts • Harmful effects of agriculture on • Biodiversity • Soil • Water • Air • Human health
Topsoil Erosion Is a Serious Problem in Parts of the World • Soil erosion: movement of soil components from one place to another by wind & water • Natural causes • Flowing water largest cause of erosion • Human causes • Farming • Clear cut logging • Overgrazing • Off road vehicle use • Two major harmful effects of soil erosion • Loss of soil fertility: depletion of plant nutrients in topsoil • Water pollution: eroded soil ends up as sediment, also includes residues of fertilizers & pesticides
Natural Capital Degradation: Severe Gully Erosion on Cropland in Bolivia
Drought and Human Activities Are Degrading Drylands • Desertification: productive potential of soil, especially on arid or semiarid lands falls by 10% or more because of prolonged drought & human activities that reduce or degrade topsoil • Moderate: 10-25% drop • Severe: 25-50% drop • Very severe: More than 50% drop • Effect of global warming on desertification
Natural Capital Degradation: Desertification of Arid and Semiarid Lands
Excessive Irrigation Has Serious Consequences • Irrigation problems • Salinization: gradual accumulation of salts due to irrigation: stunts crop growth, lowers crop yields, kills plants & ruins the land • Waterlogging: irrigated water raises the water table with salts
Natural Capital Degradation: Severe Salinization on Heavily Irrigated Land
There May Be Limits to Expanding the Green Revolutions • Can we expand the green revolution by • Irrigating more cropland? • Improving the efficiency of irrigation? • Cultivating more land? Marginal land? • Using GMOs? • Multicropping?
Industrialized Food Production Requires Huge Inputs of Energy • Industrialized food production and consumption have a large net energy loss • From farm to table about 10 units of non-renewable fossil fuel energy are needed to put 1 unit of food energy on the table • Compare that to: 1 unit of energy from human labor in traditional farming is 10 units of food energy
Industrialized Agriculture uses ~17% of All Commercial Energy Used in the U.S.
There Is Controversy over Genetically Engineered Foods • Pros • Cons • What about chimeraplasty? (Inserting chemical instructions that attach to a gene instead of gene altering)
Discussion Question 1 • Do you think that the advantages of genetically engineered golden rice outweigh its disadvantages? Explain
Food and Biofuel Production Systems Have Caused Major Biodiversity Losses • Biodiversity threatened when • Forest and grasslands are replaced with croplands • Agrobiodiversity (world’s genetic variety of animals & plants used to provide food) threatened when • Human-engineered monocultures are used • Importance of seed banks • Newest: underground vault in the Norwegian Arctic