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Agriculture. Origins of Agriculture Subsistence & Commercial Agriculture Agricultural Regions Economic & Cultural Issues. Agriculture: Terms.

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    1. Agriculture Origins of Agriculture Subsistence & Commercial Agriculture Agricultural Regions Economic & Cultural Issues

    2. Agriculture: Terms • “Agriculture is the deliberate modification of the Earth’s surface through cultivation of plants and rearing of animals to obtain sustenance or economic gain.” • “Cultivate” means “to care for.” • Any cultivated plant is called a “crop.”

    3. The Pre-Agricultural World • Human beings – or something very like human beings – have been around for several million years. • But we’ve only been practicing agriculture for something like 10,000-20,000 years. • Before agriculture there was what we call hunting and gathering.

    4. Just a few hundred thousand people (0.005% of humanity today) live an exclusively hunter-gatherer lifestyle. Based on what we know about them, and on archaeological evidence, we can make statements about what most people probably did before agriculture: Small groups (less than 50 people), low population density. Gathering is usually much more important than hunting (usually 60% to 80% of the food). In most societies men hunt and fish, and women gather. Getting food usually takes no more than 10% of people’s time. Politics are informal, consensus based; little social stratification; beliefs are animistic. Limited material culture; no permanent settlements. Strong ties to land, but nomadic and mobile. Hunters & Gatherers

    5. Origins of Agriculture • We can never know where agriculture began – it began in prehistory, and it probably began in more than one place. • However, historians, archaeologists, agronomists, geographers and other scholars have worked for over a century now trying to determine just where the processes that lead to agriculture – and to civilization – began.

    6. What does “domestication” look like? • Some of the changes that happen when plants are domesticated: • Gigantism (bigger seeds or fruits). • Loss of seed dispersal mechanisms. • Loss of bitter or toxic substances. • Loss of anti-predator mechanisms. • Some of the changes that happen when animals are domesticated: • Fast growth rate. • Tolerance of captivity. • Modified behavior (less aggressive, friendly to people, not likely to panic). • Modifiable social hierarchy (lets people be dominant). Adapted from:

    7. Carl Sauer’s theory: Not in response to hunger. Not among nomads. Not in grasslands or river valleys. In places of high environmental diversity. In places of high plant diversity. Beginning with vegetative reproduction (roots), not grains.  SE Asia 14,000-35,000 BP More conventional theory: As a consequence of gathering seeds, gatherers noted which plants produced best, and began (perhaps accidentally) to care for them. Agriculture began with crops like grains, lentils and possibly dates. Agriculture began in the river valleys – the Tigris & Euphrates, the Nile, the Indus, the Huang He, and the high valleys of Mexico and Peru.  Near East 10,000-20,000 BP Origins of Agricultureaka ‘Morphology of Landscape’

    8. Vegetative agriculture: According to Sauer, the earliest agriculture appeared in Southeast Asia, probably with root vegetables like taro and yams, and perhaps tree crops like bananas. Later diffused throughout Asia and eventually to the Near East and Europe. Independent inventions in Africa (oil palm, yam) and South America (manioc, arrowroot). Seed-based agriculture: Began in at least three places according to Sauer: Western India Northern China Ethiopia Diffused quickly from India to the Near East, then to Europe. Also developed independently in Mexico and Northern Peru. Agricultural Hearths

    9. Contrasting Theories • Your book doesn’t mention them, but at least two other people should be included here: • Nikolai I. Vavilov (1887-1943) • Looked for “centers of diversity,” which he believed were also “centers of domestication.” • Collected more than 250,000 seed samples; identified 8 agricultural hearths: Southeast Asia; China; India; Turkey-Iran; Mediterranean; Ethiopia; Mexico/Central America; Andes/Brazil/Paraguay. • Jack R. Harlan (1917-1998) • Agronomist and geneticist; actually met Vavilov at a meeting in Washington in 1932. • Defined • Three "centers": the Near East, Northern China, and Meso America. • Three “non-centers”: S.E. Asia, S. America, and Africa

    10. Diet • Most people today get most of their caloriesfromgrains – mostly corn, wheat or rice. • Protein sources can include grains or meat. • The percentage of meat consumed varies – it tends to be high in developed countries, low in developing countries.

    11. Nutrition & Hunger • According to the UN’s Food and Agriculture Organization (FAO), the average person needs to eat a minimum of 1,800 calories per day. • Actual consumption varies – in some parts of the world people eat much more than is necessary. • In developing countries the average is usually far less. Percent Undernourished Source:

    12. Nutrition is Not Just Calories Vitamin A deficiency Iron deficiency Iodine deficiency Sources:;

    13. Subsistence vs. Commercial Agriculture • Subsistence and commercialagriculture differ in five ways: • PURPOSE (consumption vs. off-farm sale) • FARM SIZE (small vs. large) • PERCENTAGE OF FARMERS (majority vs. minority of population) • MACHINERY (mostly hand vs. mostly mechanized) • FARMS & OTHER INDUSTRIES (mostly isolated vs. highly integrated)

    14. Farm Size • Data on farm size is hard to get – and different farm types (e.g. ranches vs. gardens) make meaningful comparisons difficult. • Nevertheless – we can say that in developed countries, farms do tend to be larger than in developing countries. Adapted from:

    15. Mass FarmingPros/Cons

    16. Labor Force In Agriculture • In developed countries relatively few people work in agriculture. • In developing countries the percentage of people in agriculture can be very high – often a majority.

    17. Machinery • The reason that a small number of farmers are able to feed large numbers of people in developed countries is because of machinery – tractors, cultivators, milking machines, etc. • Transportation systems are also important, as are the use of fertilizers, herbicides, advanced plant and animal breeding programs, and even electronic monitoring of crops.

    18. Also known as “slash and burn.” Most common today in tropical areas (as an adaptation to poor soils). Small-scale, no machines. Temporary – short occupation, long fallow period. Crops vary from region to region. Only 5% of the world’s population practice shifting cultivation today. Farmers clear land and burn the debris. Poor soils can only support crops for two-three years. Subsistence Agriculture:Shifting Cultivation Source:

    19. Based on herding domesticated animals. Adapted to dry climates where other types of agriculture are basically impossible. Mostly in North Africa, Near East and Central Asia Choice of animals varies – dromedary camels, sheep and goats in North Africa and Arabia, bactrian camels and horses in Central Asia, etc. Nomads don’t just “wander” – precise migration patterns, strong sense of territory. Some nomads practice transhumance: seasonal migration up and down mountains. Subsistence Agriculture:Pastoral Nomadism Source:

    20. Practiced in areas of high population den- sity – East, South and Southeast Asia. Extremely small farms, worked by hand (few machines), focused on rice. Rice is unique: it can grow in water (well, in flooded fields). Flooded fields have many advantages: pest control, easy fertilizing, fish production. Where climate is favorable, farmers can double crop – raise more than one crop per field per year. Wet rice (“paddy” or “sawah” grown) cultivation is complex: Rice seed is planted in a nursery, and raised until ready to be transplanted. Fields are prepared and plowed. Fields are flooded. Individual seedlings are planted, individually, in the flooded field. Each plant is cared for individually until harvested, by hand, with special knives. Subsistence Agriculture:Intensive (Wet Rice Dominant) Source:

    21. Rice Farming in Japan…make the Lousiana

    22. Subsistence Agriculture:Intensive (Wet Rice Not Dominant) • This is a very ancient form of agriculture – think of places like Medieval Europe, or rural Latin America, as well as more arid parts of South and East Asia. • Widely practiced in areas where climate doesn’t support wet rice. • Similar in many ways to areas where wet rice dominates, but emphasizes different crops (wheat, barley, corn, etc.). • In these areas farmers practice crop rotationto increase yields and maintain the health and fertility of their farms. Source:

    23. European Crop Rotation

    24. Integration of livestock (sheep, cattle, goats, chickens etc.) and crop farming. Most crops raised are fed to animals. Most land is devoted to crops. Most money is generated from animals and animal products. Advantages: Livestock supply manure to fertilize the crops. Workload can be more evenly distributed throughout the year. Less seasonal variation in income. Commercial Agriculture:Mixed Crop & Livestock Farming Source:

    25. Dairy products (butter, cheese, etc.) are extremely valuable. Mostly produced in Western Europe, North America, Russia, Australia and New Zealand. Because milk is extremely perishable, dairy operations traditionally located near markets – in the milkshed. Today, transportation makes it possible for milk producers to locate hundreds of miles from markets. However, the further from markets, the less likely dairy operations are to produce fluid milk (favoring butter, cheese and powdered milk). Commercial Agriculture:Dairy Farming Source:

    26. Grains – wheat, corn, oats, barley, rice, etc. – are grasses. Globally, though more rice and corn are actually grown, the most important crop is wheat – more wheat is exchanged in international commerce than any other grain. Wheat is usually produced in areas where it is too dry for mixed farming (or corn). The US is the largest grain producing region on earth. Winter wheat region (wheat planted in fall, dormant through winter, grows and is harvested in late spring or summer). Spring wheat region (wheat planted in spring, harvested in late summer). Other wheat regions (Eastern Washington) Other major producers include Canada, Argentina, Australia, France and the UK. Large scale production only became possible in the 19th century, with the development of mechanized agriculture. Commercial Agriculture:Grain Farming Source:

    27. Ranching is, in some ways, a commercial version of pastoral nomadism. Ranching is a type of commercial agriculture adapted to areas which are too dry for other forms of agriculture. Ranching is not as profitable per acre as farming – if irrigation makes farming possible, ranching usually ends. Commercial Agriculture:Livestock Ranching

    28. Intensive vs. Extensive • Intensive: • Large amounts of labor and capital relative to the land being used • Examples: Large ranches and small farms • Extensive: • Small amounts of labor and capital relative to the land being used • Examples: small ranches and large farms

    29. US Cattle Ranching • Cattle ranching in the Americas began with Columbus's second voyage. • Cattle ranching was small scale on the US East Coast in the 16th to 18th centuries; it was large and based on open rangeland in Northern Mexico (including California). • Rapidly expanding cities became major markets for beef. • In the Western US, arid areas could be used to produce beef cattle – the problem was getting the beef to market. • The solution – long-distance cattle drives, from rural areas to the nearest railroad. • By the end of the 19th century, long-distance cattle drives were basically over: • End of open range. • Expansion of railroads. • Changes in cattle breeding. • Cattle ranching changed to mostly fixed location ranching. Deep Hollow Ranch on Long Island, New York, was established in 1658, and claims to be the oldest cattle ranch in the US. Sources:;

    30. Some cattle are still raised on ranches, but most are on shifting pastures. Many cattle are now shipped to feed lotsfor fattening near their market. Ranching is also practiced in other developed countries: Spain and Portugal. Argentina, Brazil, Uruguay. Australia. Ranching Today Sources:;;

    31. “Commercial Gardening & Fruit Farming” – or “Truck farming” – has nothingto do with trucks or trucking! The word "truck" comes from an old English word meaning "to carry" or "to exchange." Specialty fruit and vegetable farming. Fresh fruits and vegetables – perishable produce. Farmers tend to specialize in a few profitable crops. Traditionally grown near markets, on small plots. With modern transportation, areas like California's Central and Imperial Valleys, Arizona's Gila River Valley, parts of Texas, Florida, Georgia, etc. have basically become truck farming areas for the whole country. Commercial Agriculture: Truck Farming Source:

    32. Adapted to the Mediterranean climate region – warm dry summers, mild wet winters (this is a very odd pattern – most places get plenty of precipitation in summer). Most crops grown for human consumption – not animal feed. Primary source of the world's olives, grapes, etc. Wheat and other grains are also grown in traditional Mediterranean areas (but mostly for local consumption). Animals and animal products of less importance (at least traditionally). Commercial Agriculture:Mediterranean Agriculture Source:

    33. No matter what your book says – plantations are not a form of subsistence agriculture! Plantations today are almost always in the tropics, and in less developed countries. Often foreign or absentee owners. Labor can be imported to an otherwise uninhabited area. Crops are grown almost exclusively for sale in distant markets – mostly in developed countries. Specialization in one or two crops (for example, bananas, tea, coffee, teak, oil palm, sugar, rubber, tobacco, etc.). Commercial Agriculture:Plantation Agriculture Teak, Thailand Pineapples, Hawaii Sources:;

    34. Fishing & Aquaculture • Globally, fish supply just 6% of the protein people consume – but in East Asia it’s over 25%. • The world’s oceans are divided into 18 major fishing regions. Most – especially in the North Atlantic, and East China Sea – have been badly overfished. • As a result, aquaculture – “fish farming” – has become very important.

    35. Fishing vs. Aquaculture and the “Law of the Sea” Under the 1994 “Law of the Sea,” countries can claim an “Exclusive Economic Zone” of 200 miles along their coasts. Notice that the area countries claim can be much larger than the country itself. The US has not signed or ratified the Law of the Sea treaty. Source:

    36. Aquaculture: Farming the Seas Sources:;;;

    37. Agriculture & the Environment • Agriculture is constrained by: • Climate • Terrain • Soil • Yes, it's possible to grow tomatoes in Iceland or lettuce in Saudi Arabia – but it's expensive, and takes sophisticated technology. • Agriculture can have a strong – even devastating – impact on the natural environment: • Slash-and-burn agriculture (if poorly done, can ruin forest lands for years) • Overgrazing (can cause soil loss, erosion) • Desertification (agriculture practiced on marginal lands can degrade land, expanding arid areas) • Irrigation • Salinization • Waterlogging Severe salinization, San Joaquin Valley Source:

    38. Climate & Agriculture Regions • Climate and agriculture regions are similar –not identical, but similar.

    39. Soil Salinization • Salinization is the concentration of salts in topsoil. • Salinization occurs naturally in arid areas. • Poor agricultural practice — especially in arid climates — can turn fertile farms into a wasteland.

    40. Global Soil Degradation

    41. Challenges: Agriculture & Population Growth • Population growth: • A rising population means that subsistence farmers mustproduce more food. To do that, there are different strategies: • Expand agricultural land • Increase productivity (“green revolution”) • New food sources (new crops) • Expand exports (bring in food from other places) • Diet modification

    42. Expanding Agricultural Land • Only about 11% of the world’s land is currently being used for agriculture. • By increasing the area in production, we can expand the food supply. • Problems • Environmental problems (soil degradation, salinization) have made some farmland unusable. • Expanding urban areas frequently take farmland out of production. • Most of the earth’s remaining land is not suitable for agriculture – too hot, too cold, too steep – without enormous modification and improvement.

    43. Arable Land Per Capita Source:

    44. Reducing Environmental Damage: No-Till Farming • Traditionally, farmers till the soil (hoe, weed, turnover, furrow, etc.) to prepare the land for planting. • Tilling works – but it has side effects: • Soil compaction • Loss of organic matter • Loss of soil bacteria • Soil loss • To stop these problems, starting in the 1940s agricultural scientists started exploring the idea of “no-till” farming. • No-till has great promise: • Reduce costs • Reduce need for fertilizer, irrigation • Improve soil • Reduce erosion • There are some problems: • May increase need for pesticides • May require new equipment, skills • May require crop rotation No-Till in Nebraska 1990-2006 % Acreage Planted Sources:;

    45. Increasing Productivity • We have already made enormous improvements in productivity – better fertilizers, pesticides, herbicides, farm machinery – and better plants through the green revolution. • By continuing to improve technologically (especially with genetically modified crops), we can increase food supplies for the foreseeable future. • Problems • Hybrid seed, fertilizers, pesticides, farm machinery, etc. are expensive, and may be impossible for poor farmers to afford. • Genetically modified crops are controversial, and may be unacceptable.

    46. New Food Sources • We get most of our food from a very limited number of plants and animals – rice, wheat, corn, sorghum and millet, potatoes, sweet potatoes, cows, pigs, chickens and sheep. • By expanding our horizons we can gain access to enormous new resources. • Strategies • Ocean farming • New high-protein cereals • Encourage use of underused foods • Problems • Most of the strategies are enormously more difficult than our current approaches – which is why haven’t been doing them. • In many cases they require expensive inputs of energy and resources, and may require people to change their way of life.

    47. High-Protein Cereals Golden rice “Green Revolution” rice Eastern gamagrass Sources:;;

    48. New Food Sources Cuphea species for oil Amaranth species for grain, oil, and vegetables Indian Rice Grass flour Sources:;;

    49. Increasing Food Exports • As productivity increases around the world, countries that once had to import food can become food exporters – and the price of food will come down. • Problems • Not all areas can produce surpluses, even with new crops or techniques. • Increasing reliance on foreign sources of food is a potential political problem, as well as a source of economic uncertainty.

    50. Agricultural Trade: Exporters & Importers