GEOG 5 1st Edition 1 Agriculture and Domestication Agriculture o o o o o Final Exam Study Guide Cultivation of plants and animals for human use Remove certain species to focus nutrients light and water on other species weed them eradicate animals etc Most of the world works as farmers We not only are influenced by evolution but we are also involved in influencing the factors of evolution direct indirect ways we influence evolution The Origins Diffusion of Agriculture The Neolithic Revolution Begins around 10 000 B P 8000 BC Appears in several independent locations indigenous crops that were able to be cultivated Domestication o o o Gradual Unplanned Process Hunting Selective Hunting Herding Selective Breeding Genetic Modification Plant domestication Most of the World s food is directly and indirectly provided by 14 crops In order of importance Wheat Rice Maize Potatoes Sweet Potatoes Manioc Sugarcane Sugar Beet Common Beans Soybeans Barley Sorghum Coconuts and Bananas 2 Why did Hunter Gatherers Shift to Agriculture These notes represent a detailed interpretation of the professor s lecture GradeBuddy is best used as a supplement to your own notes not as a substitute In a Resource Rich Environment Hunting and Gathering Produces 50 kcal of NRG per 1kcal expended Agriculture Produces 17kcal of NRG per 1kcal expended What is the incentive to switch to agriculture o Demographic Hypotheses o o Population Growth best reason Agriculture provides more NRG per Unit of Land Hunting Technology Increasing Population Less Resources Reduced Mobility Agriculture Intensification of Land Use Agriculture is an Auto Catalytic Process o o increase in population increase in the intensification of Agriculture Loss of Hunting Gathering Knowledge Dependency 3 Grain Legume Complexes and Examples Found in Major Centers of Domestication Legumes act as Nitrogen Fixers Bacteria Nodules on Roots Legumes tend to have bacteria and live in a symbiotic relationship where the waste product is nitrogen Plants need nitrogen in order to live Serves Two Functions o o 1 Maintain Soil Fertility 2 Provide Carbohydrates Protein In our three main sources of crops each had grain legume complexes 4 Centers of Domestication and some major crops Farmland and People 2000 o o o Southwest Asia 8500 B C Wheat barley pea lentil chickpea etc Fertile Crescent Iran Iraq Independent origin o o Location Asia Africa North America South America Europe Australia World Asia intensive more labor North America extensive use of the land Agriculture diffused from the Fertile Crescent Wheat carbohydrate peas protein China 7500 BC o o o Millet Rice main crop Soybean Pig Silk Worm Millet grows in drier environments Independent Origin Indus Valley 7000 BC not independent Pakistan modern day Egypt 6000 BC not independent o Sesame Eggplant Humped Camel Pigs o o Fig Cat Donkey Agriculture from Fertile Crescent Egypt Western Europe 6000 3500 BC o o oats poppy rye not independent o o Corns Beans Squash Turkey Columbian Exchange Corn Meso America 3500 BC Andes Amazonia 3500 BC o Potatoes Manioc Llama Guinea Pig o Sugarcane Banana New Guinea 7000 BC Sahelian Africa 5000 BC Ethiopia o o Sorghum Coffee Teff West Africa 3000 BC o African Yams Oil Pams etc o Goosefoot Sunflowers Eastern North America 2500 BC 5 The Green Revolution Not an environmental revolution Agricultural Innovations from mid 1940s to 1970s Normal Borlang 1914 2009 Led to dramatically increased Food Yields n the Developing World India Philippines Mexico etc Involved o o o o o High Yielding Varieties HYVs New Management Practices New forms of Inputs Mechanization of agriculture in the developing world large food increase food production Critiques o o o o Industrialized Agriculture Fossil Fuels Worsened environmental problems Benefited Wealthy Farmers Exacerbated Wealth Gap 6 Environmental Impacts of Agriculture 1 Soil Erosion o o o o Wind Water Air Quality Plowing soil erosion Slash Burning soil erosion o Overgrazing o o o Caused by soil erosion Leeching Crop Removal Leeching in wet areas tropical areas Some Strategies to Combat Declining Soil Fertility Fallowing The practice of leaving a field idle for a period Builds up nutrients and moisture for the next crop Crop Rotation Nitrogen fixers 2 Declining Soil Fertility 3 Habitat Change Reduced Biodiversity o o o Mono cropping single crops are grown in one area ex cornfields for miles big issue in agriculture Simplified Morphological Structure Planting in Rows Complex Layered Hydrological Changes Irrigation Dams Ground Water etc Where are they taking the water from and how will that impact the environment 4 Fertilizers Eutrophication o o o Related to fertilizer use Eutrophication Heavy use of Fertilizers Livestock Manure Nutrients enter Water Bodies Increased Algae Growth Algae Die Decompose DeOxygenation of Water Dead Zones Fish and other types of aquatic life need oxygen o o o e g The Susquehanna River and the Chesapeake Bay e g The Growing Dead Zone in Gulf of Mexico China has serious problems with Eutrophication o o o Kills many beneficial insects too Alternatives to Pesticides and Herbicides Pesticides are best for pests Biological Control Uses biological predators to control pests e g Ladybugs e g Wasps help to control pests in the environment Integrated Pest Management IPM Developed and under developed worlds Use Biological Controls Pesticides as well as Altered Management Techniques etc Goal is Management of Pests not Eradication Spreading fast Globally leading to production increases Organic Agriculture Produced without Pesticides Herbicides or Hormones Usually Expensive 5 Pollution from Pesticides Herbicides o o o 6 Air Pollution Green House Gases o Fossil Fuel Use Livestock o o Agriculture produces 9 of CO2 37 of CH4 emissions Methane is a potent green house gasses 7 Strategies to counter the Env Impacts of Agriculture see above 6 Some Strategies to Mitigate Soil Erosion o o o o o o o o o Contour Plowing Strip Cropping mixing different crops with one another Technique used to reduce soil erosion Terracing traditional technique Not used in N America Riparian Buffers No Till Agriculture Stems and roots are left to bold soil and help replenish fertility No Till Increasing 7 1991 30 2001 8 Trophic Argument for Vegetarianism Each time you go up one level you are only transferring 10 of the energy because of cellular respiration We should be primary consumers If we are on the 2nd tropic level there is less energy loss and more energy