agriculture chapter 10. origins of agriculture agriculture- deliberate modification of earth’s...
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Origins Of Agriculture
Agriculture- deliberate modification of Earth’s surface through cultivation of plants and rearing of animals to obtain sustenance or economic gain– Cultivate-to care for– Crop-any plant cultivated by people
Agriculture began when humans first domesticated plants and animals for their use
Hunters and Gatherers
Small familial groups of 50 or less who survived by gathering plants and hunting wild animals
Most of time used to search for food Lived nomadic lifestyle with few possessions Approx. 250million people sill live this way
– Isolated areas of the Arctic, the interior of Africa, Australia, and South America
Invention of Agriculture
Plant cultivation most likely evolved from a combination of accidental and deliberate experiments
Carl Sauer theorizes there are 2 types of cultivation1. Vegetative agriculture- reproduction of plants by direct
cloning from existing plants, such as cutting stems and dividing roots (earliest form)
2. Seed agriculture- reproduction of plants through annual planting of seeds that result from sexual fertilization
Location of Agricultural Hearths
Agriculture has multiple, independent points of origin
Sauer believes vegetative planting originated in SE Asia– Climate and topography encouraged wide variety
of plants suitable for dividing and transplanting– People relied on fishing which made them more
sedentary—more time to devote to plants
continued
Crops probably included roots such as taro and yam, and tree crops such as the banana and palm
Animals probably included the dog, pig, and chicken
Other early vegetative planting hearths were in West Africa and northwestern South America
Location of First Seed Agriculture
Sauer identified 3 seed agricultural hearths in the Eastern hemisphere (western India, northern China, and Ethiopia) and 2 in the Western hemisphere (southern Mexico and northern Peru)
The western India hearth diffused quickly into southwest Asia– where wheat and barley were first domesticated
– Also first to integrate domestication of herd animals such as sheep, cattle and goats
continued
Mexico was the point of origin for squash and maize Beans and cotton may have originated in Peru Diffusion occurred from these two hearths, but
agriculture was not widespread until the arrival of the Europeans
The only domesticated animals were the llama, alpaca, and turkey before the arrival of the Europeans
Classifying Agricultural Regions
The most fundamental differences in agricultural practices are between those in LDCs and MDCs
LDCs practice subsistence agriculture Production of food primarily for consumption by the
farmer’s family
MDCs practice commercial agriculture Production of food for sale
Differences Between Subsistence and Commercial Agriculture
Five principal features distinguish commercial agriculture from subsistence agriculture
1. Purpose of farming2. % of farmers in the labor force3. Use of machinery4. Farm size5. Relationship of farming to other businesses
Purpose of Farming
For own consumption Little surplus might be
sold Might not be any
surplus because of growing conditions
Products grown for sale Sold to food-processing
companies such as General Mills or Kraft
% of Farmers in the Labor Force
More than 50% involved in agriculture
Less than 10% employed in farming
Only 2% in US and Canada, yet still produce a large surplus to sell internationally
# of farmers declined drastically during 20th century
Use of Machinery
Most work is done with hand tools and animals
Use of machinery allows a small # of farmers to feed many people
Transportation improvements such as railroads and highways get fresh products out quickly
Scientific advances also used to increase productivity– fertilizers, herbicides, hybrid plants, and animal breeding
Farm Size
Farm size is relatively large esp. in US and Canada– avg. 444 acres
98% are still family owned in US
The biggest 1.4% of US farms account for 48% of all agricultural sells they average 3000 acres
About half of all US farms generate less than $5000 a year in sales (about 100 acres on average)
continued
Large size is a consequence of mechanization
Machines work more efficiently on large plots of land and they are also too expensive to justify on small farms
continued
US is losing about 1.2 million acres of farmland per year of its 1 billion acres of farmland
Prime agricultural land- most productive farmland—alarming problem
Decreasing in US because of urban sprawl
Relationship of Farming to Other Businesses
Commercial farming is closely tied to other businesses
Agribusiness-commercial agriculture char. by integration of different steps in the food-processing industry, usually through ownership by large corporations
– farmers are less than 2% of US workforce, but 20% of labor force works in food production and other services related to agribusiness such as fertilizer production, tractor manufacturing, etc.
Mapping Agricultural Regions
Derwent Whittlesey (1936)identified 11 main agricultural regions plus an area of nonexistent agriculture– Subdivided between 5 regions that are important
in LDCs and six that are important in MDCs– Used climate to sort agricultural practices
Influences crops that are grown and if animals are raised instead of growing crops
continued
The correlation b/w agriculture and climate is not perfect, but it definitely exists– Geographers warn not to put too much emphasis
on climate because of environmental determinism
Cultural preferences explain some agricultural differences in areas of similar climate– Ex. No hogs in Muslim areas
Agricultural Characteristics of LDCs
There are 4 agricultural types characteristic of LDCs
1. Shifting Cultivation
2. Pastoral Nomadism
3. Intensive Subsistence Agriculture
4. Plantation Farming
Shifting Cultivation
Practiced in much of the world’s Humid Low-Latitude, or A, climate regions, which have relatively high temperatures and abundant rainfall
Prevalent in the Amazon are of SA, Central and West Africa, and SE Asia
Def- a form of subsistence agriculture in which people shift activity from one field to another; each field is used for crops for a relatively few years and left fallow for a relatively long time
Characteristics of Shifting Agriculture
1. Slash-and-burn agriculture
2. Fields are used until the nutrients are depleted then they are left fallow for many years so the soil can recover
People who practice usually live in small villages and grow food on surrounding land, which the village controls
The Process of Shifting Cultivation
Trees removed, undergrowth cleared and burned, ashes soak into the soil with rain to provide nutrients
Cleared land called by many names such as:– Swidden– Ladang– Milpa– Chena– kaingin
continued
Fields are prepared by hand with simple tools such as hoes—plows and animals are rarely used
Land is usually only good for three years before all the nutrients are used
– The second year after burning usually brings the best harvest
When the swidden is no longer fertile, a new area is prepared
The old field will be left to nature for a period of 6 to 20 years before it is used again
Crops of Shifting Cultivation
Predominately upland rice in SE Asia, maize and manioc (cassava) in South America, and millet and sorghum in Africa
Yams, sugarcane, plantain, and vegetables are also grown in some regions
Ownership and Use of Land In Shifting Cultivation
Land usually owned by the village and the chief or ruling council assigns individual patches to families
Private individuals do own the land in some places, especially in Latin America
About ¼ of World’s land area is used for shifting cultivation
Future of Shifting Agriculture
Land used for shifting cultivation is declining by about 30,000 sq. miles per year
Being replaced by logging, cattle ranching, and cultivation of cash crops
Leads to a lot of deforestation in the tropics
Pastoral Nomadism
Def.- a form of subsistence agriculture based on the herding of domesticated animals– Adapted to dry climates where planting crops is
impossible
Primarily done in North Africa, the Middle East, and parts of Central Asia
Only 15 million in the World, but sparsely occupy 20% of land area
Characteristics of Pastoral Nomadism
Depend on animals for survival– Provide milk, skins and hair are used for clothing
and shelter– Usually don’t slaughter for food, but those that die
may be eaten– Grain still the main source of food
May trade for it, or plant a small amount if the land will support it
Choice of Animals
Type and # chosen based on local customs and physical characteristics of land
Camels the animal of choice in North Africa and the Middle East, followed by sheep and goats
Movements of Pastoral Nomads
Have a strong sense of territoriality Groups try to control enough territory to
contain the forage and water needed for survival
Routes are based off of best chances to find water during the various seasons of the year
continued
Some nomads practice transhumance Seasonal migration of livestock between mountains and
lowland pasture areas Pasture- grass or other plants grown for feeding grazing
animals, as well as land used for grazing
The Future of Pastoral Nomadism
Declining form of agriculture Governments try to resettle them to gain land
that can be irrigated for crops or for the mining and petroleum industries
Intensive Subsistence Agriculture
Shifting cultivation and pastoral nomadism are found only in areas of low density in LDCs—they don’t produce enough to support higher densities
In those areas intensive subsistence agriculture is used
– Form of subsistence agriculture in which farmers must expend a relatively large amount of effort to produce the maximum feasible yield from a parcel of land
continued
Done in densely populated areas of Asia Because of the high agricultural density in
East and South Asia, families must produce enough food for survival off a very small piece of land
Most work done by hand or with the help of animals
Virtually no land is wasted
Intensive Subsistence with Wet Rice
Wet rice- the practice of planting rice on dry land in a nursery and then moving the seedlings to a flooded field to promote growth
Occupies small part of Asia’s agricultural land but is the most important source of food
Common in SE China, East India, and much of SE Asia
continued
Growing of rice has many steps
1. Field plowed with help of oxen or water buffalo
2. Land is then flooded with water (not too much, not too little, but just right) Flooded land called a
sawah not a paddy, which actually means wet rice
continued
3. Plant seedlings on dry land then transplant them into the sawah
4. Plants are harvested by hand using knives
5. The husks (chaff) are separated from the seeds by beating them (threshing) on the ground
6. Threshed rice is put in a tray and the lighter chaff is winnowed—blown away by the wind
continued
Wet rice more easily grown on flat land
– Most takes place in river valleys and deltas
– Hillsides are often terraced t provide more land for cultivation
continued
Double cropping, harvesting two crops in one year from the same field, is used in places with warm winters to increase food production
Involves alternating between wet rice in the wetter summer months with wheat or barley in the winter
Intensive Subsistence with Wet Rice Not Dominant
The climate in some parts of Asia is not conducive to growing wet rice (interior of India and NE China)
The crop is different but the characteristics are much the same
Land used to its fullest, and hand tools and animals are used
Wheat and Barley are the most important crops grown for food
Cotton, flax, hemp, and tobacco are grown for sale
continued
In some areas crop rotation can be used to get more than one harvest
– Def. as the practice of rotating different fields from crop to crop each year to avoid exhausting the soil
Plantation Farming
Found in tropics and subtropics of Latin America, Africa, and Asia
Often owned by Europeans or North Americans and crops are made for sale in MDCs
Def.- a large farm that specializes in one or two crops– Cotton, sugarcane, coffee, rubber, and tobacco
are common crops
continued
Import workers and provide food, housing, and social services
Managers try to spread the work as evenly as possible throughout the year to make full use of the large labor force
Where climate permits, more than one crop is planted and harvested during the year
Where are Agricultural Regions in More Developed Countries?
6 main types of commercial agriculture in MDCs:
1. Mixed crop and livestock
2. Dairy farming
3. Grain farming
4. Livestock ranching
5. Mediterranean agriculture
6. Commercial gardening and fruit farming
Mixed Crop and Livestock Farming
Most common type of agriculture west of the Appalachians and in much of Eastern Europe
Most of crops are fed to animals rather than consumed by humans
The livestock supply manure to improve fertility to grow more crops
Typical farm devotes almost all land to growing crops, but gets more than ¾ of income from sale of animal products like beef, milk, or eggs
continued
This type of farming allows farmers to distribute the workload more evenly throughout the year– animals always need tending to, not just during planting and harvesting
Also reduces seasonal variations in income
continued
Crop rotation is often used in mixed crop and livestock farming
Corn is the most common crop in the US because higher yields than other crops
Some of the corn is consumed by humans directly or as oil, margarine, and other food products, but most is fed to pigs and cattle
continued
The Corn Belt, Ohio to the Dakotas, is the most important mixed crop and livestock farming region
Soybeans have become the second most important crop in US mixed commercial farming regions
Dairy Farming
Most important commercial agriculture practiced near large urban areas of the NE US, SE Canada, and NW Europe
India is now the World’s largest producer of Milk, followed by the US, Pakistan, China, and Russia
Why Dairy Farms Locate Near Urban Areas
Milkshed- the geographic ring around a city from which milk can be supplied without spoiling– Since milk is highly perishable dairy farms must
be closer to their markets than other types of farms
– Transportation improvements have allowed dairy farms to be located further away than their market
– 1840s milkshed was about 30 miles, now about 300 miles
continued
Some dairy farms specialize in products other than milk such as butter and cheese
In the US, the product selection is based upon whether the farms are within the milkshed of a large urban area
The farther away the farm from an urban area, the less milk they produce
Most farms in the East make milk, in Wisconsin most is processed into cheese and butter
Continued
Like most commercial farmers, dairy farmers do not sell their products directly to consumers
– Produce is sold to wholesalers, who distribute to retailers, who sell it to consumers
Challenges for Dairy Farmers
Face declining revenues and rising costs Farming is labor intensive-cows must be milked 2
times every day Cows must be fed in winter months when they can’t
graze on grass # of farms with milk cows declined in the US by 2/3
between 1980 and 2000, but the # of cows declined by only 1/8, and production increased by ¼
– Individual cows are producing more milk
Grain Farming
Grain- the seed from various grasses, like wheat, corn, oats, barley, rice, millet, and others
On a grain farm the crops are grown for consumption– Crops sold to food manufacturers
Most important crop is wheat, which is used to make flour
Can be sold for a higher price than other grains and stores well without spoiling
It is also the World’s largest export crop
continued
US and Canada account for half of world’s wheat exports
Plains areas are called the world’s “breadbasket”
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The US is by far the world’s largest commercial producer of grains for sale
Canada, Argentina, Australia, France, and the UK are amongst the few others that produce grain on a large scale
continued
In North America, large-scale grain production is concentrated in three areas:
1. Winter-wheat belt (planted in autumn to develop roots before winter and harvested in early summer)- runs thru Kansas, Colorado, and Oklahoma
2. Spring-wheat belt (planted in spring and harvested in late summer)- includes the Dakotas, Montana and southern Saskatchewan
3. Washington State – Palouse region 2/3 comes from winter and spring belt
continued
Grain farming is heavily mechanized McCormick reaper (1830s) permitted large-
scale wheat production– Allowed grain to be cut while its standing in the fields
Today the combine performs in one operation the tasks of reaping, threshing, and cleaning
continued
Amount of work is not uniform throughout the year
Farms often include two sets of fields – one in spring-wheat belt and one in the winter-wheat belt to spread work to other times of year
Same set of machines can be used on both farms in this manner
Livestock Ranching
Ranching- the commercial grazing of livestock over an extensive area
– Adapted to arid or semi-arid land– Done in MDCs where crops cannot be supported
Cattle not indigenous to the Americas– First brought by Columbus on his second voyage
Thrived and multiplied on plains of NA Demand for beef in Eastern US cities drove the expansion of
ranching during 1860s “Cattle drives”
Fixed Location Ranching
Cattle ranching declined in the 1880s when it began to conflict with sedentary agriculture
“open range” owned by US government, began to be sold to farmers who didn’t want cattle roaming thru their fields
Cattle ranchers now had to buy land to graze their cattle
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The predominant breed of cattle also was changed to be better suited to fixed location ranching– Ex. Herefords are better suited to fixed location
than longhorn who were better suited for the long drive
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Ranching has declined as irrigation has allowed more land to be planted with crops
Ranches are very large and are often operated by meat-processing companies
Ranching Outside the US
Rare in Europe– Except the Iberian Penn. (Spain and Portugal)
Large portions of Argentina, southern Brazil, and Uruguay are used for cattle and sheep
Australia, the Middle East, New Zealand, and South Africa have lots of sheep
Commercial Ranching is different than pastoral nomadism in that ranching is part of the meat processing industry rather than just small isolated farms
Mediterranean Agriculture
Exists primarily on lands that border the Mediterranean Sea in Southern Europe, North Africa, and Western Asia
– Also done in CA, central Chile, and southwestern South Africa
These places have similar physical environments Sea winds provide moisture, winters moderate,
summers hot, land hilly– Strips of flat land along the coast
continued
Smaller proportion of income comes from animals than in mixed crop and livestock farming
Transhumance used with sheep and goats Most crops are grown for human consumption Horticulture, the growing of fruits, vegetables, and
flowers, along with tree crops make up the bulk of Mediterranean agriculture
– Olives, grapes, fruits, and vegetables are grown here
continued
2/3 of world’s wine produced in the actual Med. Sea area – other 1/3 produced in Med. Agricultural regions
Largest supply of Olive Oil also comes from Med. Sea area
Much of Med. Sea land is also used for cereal grains to make bread and pasta
In CA, much land is devoted to fruit and vegetable horticulture –citrus fruits, tree nuts and deciduous fruits
Commercial Gardening and Fruit Farming
Predominant type of agriculture is SE US– Long growing season, humid climate, and accessible to
large markets in Eastern US
Often called truck farming From the Middle English word meaning bartering or the
exchange of commodities
Grow many of the fruits and vegetables that consumers demand in more developed societies
– Ex. Apples, asparagus, cherries, lettuce, mushrooms, and tomatoes
continued
Some sold fresh to consumers, but most sold to large processors for canning or freezing
Highly mechanized Hire migrant workers to keep costs down Individual farms tend to specialize in a few crops,
and sometimes a handful of farms dominate the production of some fruits or veggies
Specialty farms have spread to New England– Type of truck farm that specializes producing veggies for
wealthy markets –things like peppers, asparagus, and strawberries
Importance of Access to Markets
Purpose of commercial agriculture is to sell the produce– Therefore, the distance from the farm to the
market influences the type of crop Ex. Dairy needs to be relatively close to the market
Von Thunen Model
Attempts to explain the importance of proximity to the market in the choice of crops
First proposed in 1826 in a book called The Isolated State
Farmers look at two type of costs
1. Want a crop that can be sold for more than the land costs
2. The cost of transporting the crop to the market
continued
The value of the yield per hectare and the cost of transporting the yield per hectare are used to select the most profitable crop
Crops with higher transportation costs are grown closer to the market, distant farms are likely to select crops that can be transported less expensively
Challenges for Commercial Farmers
They are victims of their own success They produce so much that it drives down
the price Government subsidies help prop up farm
income
continued
US gov. has three policies to address the problem of excess production
1. Farmers are encouraged to avoid producing crops that are in excess supply
2. Gov. pays farmers when certain commodity prices are low (gov. sets target and pays farmers the diff. b/w target and what they actually sell it for)
3. Gov. buys surplus production and sells or donates it to foreign gov.s
continued
US spent $25 billion on farm subsidies in 2005
Farming in Europe is subsidized even more in the US
In MDCs farmers are encouraged to grow less food. whereas LDCs struggle to increase food production to match the rate of growth in the population
Sustainable Agriculture
Def.- an agricultural practice that preserves and enhances environmental qulaity– Generate lower revenues, but also have lower
costs
Organic farming is a pop. form
continued
3 practices distinguish sustainable agriculture from conventional agriculture
1. Sensitive land management
2. Limited use of chemicals
3. Better integration of crops and livestock
Sensitive Land Management
Ridge tillage- practice of planting crops on ridge tops– Helps lower production costs and increases soil
conservation
Limited Use of Chemicals
Little to no herbicides used to kill weeds– Does require more time and expense
Integrated Crop and Livestock
Sustainable agriculture is sensitive to the complexities of biological and economic interdependence between crops and livestock
Read page 353 to learn more
Challenges for Subsistence Farmers
2 major issues challenge subsistence farmers in LDCs
1. LDCs= stage 2 of demographic transition-therefore, must feed a rapidly growing pop.
2. Because of international trade approach to economic development, subsistence farmers must grow food for export rather than direct consumption
Strategies to Increase the Food Supply
1. Expand the land area used for agriculture
2. Increase the productivity of land now used for agriculture
3. Identify new food sources
4. Increase exports from other countries
There are challenges to each of these options
Expanding Cultivated Land Area
Can lead to desertification if land is not used properly
– Process of land deteriorating to desert-like conditions because of human use
Happens in semi-arid areas
Increase Food Supply Through Higher Productivity
Green revolution- the rapid development and diffusion of more productive agricultural practices during the 1970s and 1980s
Involved the introduction of higher yield seeds and the expanded use of fertilizers