agriculture n.
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  1. Agriculture • Definition, origins, classification • Agriculture in LDCs • Agriculture in MDCs

  2. I. Definition, origins, classification • Agriculture: • Deliberate modification of a portion of earth’s surface through cultivation of plants or raising animals • To obtain sustenance (LDCs) or for economic gain (MDCs)

  3. Hunting and gathering: • Small groups, fewer than 50 people • Today, only ¼ million people still survive by hunting and gathering


  5. Invention of agriculture • Accident and deliberate experiment • Two types of cultivation: • Vegetative planting: cloning from existing plants • Seed agriculture: came later, planting of seeds, practiced by most farmers today

  6. Hearths: agriculture began in multiple, independent hearths (points of origin) (Carl Sauer) • Vegetative planting • Southeast Asia • West Africa • NW South America

  7. Seed agriculture • 3 hearths in the Eastern Hemisphere • Western India • Northern China • Ethiopia • 2 hearths in Western Hemisphere • Southern Mexico/Mesoamerica (squash and corn) • Northern Peru


  9. The Fertile Crescent • Mesopotamia, between the Tigris and Euphrates Rivers

  10. Advantages of the Fertile Crescent • 1. Mediterranean climate • 2. Numerous edible and productive plants • 3. Self pollinate, cross pollinate • 4. Wide range of elevations • 5. Numerous large animals • 6. East-west axis

  11. Classifying agricultural regions • Difference between LDCs (subsistence) and MDCs (commercial) • 1. Subsistence agriculture: growing food for consumption by farmer’s family • 2. Commercial agriculture: growing food for sale off the farm (machinery and technology)

  12. Commercial Subsistence

  13. Today the US is losing farmland1.2 million acres per year of a total of 1 billion acres

  14. urban expansion

  15. Agribusiness • Commercial farming in the US and other MDCs is called agribusiness • Agribusiness includes processing, packaging, storing, distributing, and retailing; tractor manufacturing, fertilizer production, seed distribution… • Farmers are less than 2% of the US labor force • But 20% of US labor works in food production and service • Many aspects of agribusiness are controlled by large corporations


  17. II. Agriculture in LDCs • Shifting cultivation • Humid low-latitude/tropical zones (high temp and rainfall), low population density • 2 types • Slash-and-burn: clearing land by cutting vegetation and burning debris (tropical zones) • Rotation: using a field for a few years, then leaving it fallow for many years


  19. Pastoral nomadism • A form of subsistence agriculture based on herding domesticated animals • Dry climates, where crops can’t grow, low population density • Most in arid and semi-arid land in North Africa, the Middle East, and Central Asia (Eastern Hemisphere) • Transhumance: seasonal migration of livestock between mountains (summer) and lowland pastures (winter) • Pasture: land used for grazing, and grass or other plants grown for feeding grazing animals


  21. Intensive subsistence agriculture • Farmers must work more intensively to subsist on a parcel of land • Farms are smaller, so more pressure for productivity • Practiced in densely populated areas (East, South, and Southeast Asia) • Wet rice dominant: mostly in river valleys and deltas, or in flat or terraced fields • Wet rice not dominant: climate prevents farmers from growing wet rice in parts of Asia, where summer precipitation is low and winters are harsh


  23. Plantation farming • A form of commercial agriculture in tropics and subtropics (Latin America, Africa, Asia) • Mostly in LDCs, but many owned by people in MDCs, and most products for sale in MDCs • Plantation: a large farm that specializes in one or two crops


  25. III. Agriculture in MDCs • Mixed crop and livestock • Most crops fed to animals

  26. Crop rotation systems • Farm split into fields, and each field planted on a planned cycle, often several years (1 year fallow and cycle is repeated) • Different from shifting agriculture in LDCs because LDCs leave fields fallow for many years and productivity is lower • 2-field crop rotation system (Northern Europe, 5th century) • Cereal grain planted in Field A for one year, Field B fallow • 3-field system (8th century) • Field 1 planted with a winter cereal, Field 2 a spring cereal, Field 3 left fallow • 4-field system (NW Europe, 18th century) • First year: root crop in Field 1, cereal in Field 2, rest crop in Field 3, and cereal in Field 4 • Second year: cereal in Field 1, rest crop in 2, cereal in 3, and root in 4

  27. Dairy farming • Dairy used to be consumed on farms or in rural villages, but in the 19th century demand from urban residents increased • Dairy farms locate near urban areas: the ring surrounding a city from which milk can be supplied without spoiling is known as the milkshed • Before the 1840s, milksheds had a radius of less than 30 miles • Today milk can be transported more than 300 miles

  28. Von Thunen Model

  29. Grain farming • Grain: the seed from various grasses, like wheat, corn, oats, barley, rice, millet, and others • Grain is the major crop on most farms • Different from mixed crop and livestock farming because crops on a grain farm are grown primarily for consumption by humans

  30. Wheat • Benefits: • Can be sold for a higher price • Has more uses than other grains • Can be stored easily • Can be transported a long distance • Grown extensively for international trade and the world’s leading export crop • The US and Canada account for half the world’s wheat exports

  31. In North America, large-scale grain production is concentrated in 3 areas: • 1. Winter-wheat belt (Kansas, Colorado, Oklahoma): planted in fall, harvested in summer • 2. Spring-wheat belt (Dakotas, Montana, southern Saskatchewan): planted in spring, harvested in summer • 3. Palouse region in Washington state • The result in the US is a staggered harvest, starting in the south and progressing north


  33. Livestock ranching • Ranching: the commercial grazing of livestock over an extensive area (semiarid and arid land in MDCs) • The only European countries involved in cattle ranching are Spain and Portugal • Outside the US: Spain and Portugal, Argentina and Brazil, and Australia • Ranching has gone through stages • Herding of animals over open ranges (seminomadic) • Fixed farming by dividing land into ranches • Farms converted to growing crops and ranching confined to drier lands

  34. Mediterranean agriculture • Where? • Lands that border the Mediterranean Sea in southern Europe, North Africa, and western Asia • Also in CA, Chile, South Africa, and Australia • Every area borders a sea • Sea winds provide moisture and moderate the winter, summers are hot and dry • Land is hilly and mountainous • Tree crops and horticulture (the growing of fruits, vegetables, and flowers) • Olives, grapes, fruit, vegetables, citrus, tree nuts • Half the land devoted to growing cereals (wheat for pasta and bread)