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11/4 Bellringer : Conventional Agriculture What is agriculture? What is the #1 crop produced in the U.S.? What are the positive results of large scale agriculture? Wha t are the negative impacts of industrial agriculture. . Conventional Agriculture. The History of Agriculture.
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11/4Bellringer: Conventional Agriculture • What is agriculture? • What is the #1 crop produced in the U.S.? • What are the positive results of large scale agriculture? • What are the negative impacts of industrial agriculture.
The History of Agriculture • Agriculture is the raising of crops and livestock for food or for other products that are useful to humans. • Began over 10,000 years ago • This period was called the Agricultural Revolution • Prior to humans were primarily hunter-gatherers • Agriculture allowed human population to grow at unprecedented rates http://www.xtimeline.com/timeline/History-of-agriculture-1
Origins of Agriculture • Farming was first used in the Middle East, in a region running from present-day Turkey to Iraq and Israel, called the Fertile Crescent. • Barley and wild wheat were abundant and flood river plains were used.
Agricultural Revolution: Crash Course (1:05-6:45) • https://www.youtube.com/watch?v=Yocja_N5s1I
Agricultural Revolution • Plants we grow and eat (domesticated) today are descended from wild plants • Teosinte: ancestor of modern corn • Farmers collected seeds from plants that exhibited the qualities they desired • Seeds were planted and harvested again and again Evolution of Corn Teosinte vs. Zea Mays
Agriculture Models • Subsistence agriculture: growing food for consumption by farmer’s family • Commercial (modern) agriculture: growing food for sale off the farm, heavy use of machinery, fossil fuels, and technology • Modern Agriculture • Large acreage • Monoculture • Extensive use of fertilizers • Extensive use of pesticides • Irrigation • Subsidies to overproduce • Selection of cash crops following subsidies • Crop selection for animal feed • Sustainable Agriculture • Small acreage • Crop rotation • Co-planting • Fallow fields • Regionally-appropriate crops • Locally eaten and sold
Agricultural Revolution • Destruction of habitats • Grasslands, forests, and wetlands were replaced with farmland • Replacement of forest • Soil loss • Floods • Water shortages
Agribusiness • Agribusiness is a term that encompasses all the businesses involved in agricultural food production, including farming, contract farming, seed supply, agrichemicals, farm machinery, distribution, processing, marketing, and retail sales. • One of the largest and most diverse industries in the US. Estimated 2012 revenue = $2.4 trillion • Major industry stakeholders • Monsanto, Cargill, ADM (Archer Daniels Midland), etc.
U.S. Crop Production • U.S. farmers produce roughly $100 billion worth of crops and about $100 billion worth of livestock each year. (EPA 2012) • In 2010, 335 million acres of land were used for crop production. (Census 2012) • USDA Land Use Survey in 2002, 442 million acres (20%) were used for crop land • 587 million acres (26%) were used for grassland pasture and range land. If you combine crop and rangeland, that’s nearly ½ of the United States!
U.S. Crop Production http://www.epa.gov/oecaagct/ag101/cropmajor.html
Farmers in the U.S. • In 1935, the number of farms in the United States was 6.8 million. In 2007, the number of farmers was down to 2.2 million. • The need for human labor has also declined as evidenced by the increase in agricultural labor efficiency over the the past century. • Average age of farmers is 54 years old in 1997. Average age of farmers is 57 years old in 2007. Average age of farmers is increasing.
Earl Butz and Subsidies • Earl Butz was the head of the Department of Agriculture in the 1970’s. • His major change was that he promoted bigger farms and encouraged “get big or get out.” • He was responsible for creating direct payments to grow corn = subsidies.
Corn (Zeamays) • Corn is the most heavily subsidized crop by the U.S. Department of Agriculture (USDA) • Corn is the major source of food in the American diet • Almost everything Americans eat contains corn: high fructose corn syrup, corn-fed meat, and corn-based processed foods are the staples of the modern diet. • One bushel of industrial corn requires ¼ to 1/3 gallons of oil for production (Pollan, Omnivore’s Dilemma) • = 50 gallons of oil/acre of corn
Monocultures • Growing a single crop or plant species over a wide area for many years. • ex. lawns, corn fields, tree farms • Widely used in industrial agriculture for large crop yields with little labor input. • However, they can lead to quicker spread of disease or use more soil nutrients.
Livestock, Dairy, & Poultry • Domesticated animals raised for product output or slaughtered for consumption. • Animal products account for over half of the value of U.S. agricultural products, often exceeding $100 billion per year. (USDA 2012) • Issues include overcrowding to maximize profit in large-scale operations, disease spread in monocultures, use of antibiotics, excessive waste output, and treatment.
Dairy Cows • Trace amounts of hormones, blood, and pus can be found in milk from industrial processes
Poultry Farms • Chickens are often “debeaked” to prevent damage and cannibalism at crowded farms
Energy Inputs vs. Outputs Kilocalories of fossil fuel input per kilocalorie of protein output Feed lot beef Pigs Broiler Chicken Free range beef Sheep Vegetables
Fish Farms • Issues include over crowding (does not occur in the wild) - can cause disease, stress, and pollution, and local habitat destruction • Dead or diseased fish are often ground up and fed to live fish Sea lice
Slash and Burn • Agricultural technique which involves cutting and burning of forests to create fields • commonly used practice in the Amazon • Typically used in subsistence farming since it needs little technology or tools
Environmental Impacts of Agriculture • High use of fossil fuels and pesticides • Air pollution • Pressures on non-renewable resources • Untreated animal wastes and agricultural chemicals • Water pollution • Harms fisheries • Insects, weeds, and disease-causing organisms developing resistance to pesticides • Contaminate food supply
Pesticides Residue on Produce Highest Lowest Apples Asparagus Bell peppers Avocados Celery Bananas Cherries Broccoli Imported grapes Cauliflower Nectarines Corn (sweet corn) Peaches Kiwi Peas Mangos Potatoes Onions Red Raspberries Papayas Spinach Pineapple Strawberries Peas (sweet) Released 10/21/2003 by EWG
Environmental Impacts of Agriculture • Land degradation • Decreases future ability of land to support crops or livestock • Habitat fragmentation • Breakup of large areas of habitat into small, isolated patches • Cultivating marginal lands • Irrigating dry land • Cultivating land prone to erosion
Genetic Engineering • Manipulation of genes by taking specific gene from a cell of one species and placing it into the cell of an unrelated species
Your Assignment: • On a separate sheet of paper: • Draw (with labels) an IDEAL Sustainable Farm that doesn’t have all the problems that Conventional Farming does.
Modern Agriculture • Exit Slip