Term
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Definition
| Accumulation of salts in soil that can eventually make the soil unable to support plant growth. |
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Term
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Definition
| Occurs when surface water or wind peel off fairly thin sheets or layers of soil. |
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Term
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Definition
Clearing a plot of ground in a forest, especially in tropical areas, and planting crops on it for a
few years (typically 2 - 5 years) until the soil is depleted of nutrients or the plot has been
invaded by a dense growth of vegetation from the surrounding forest. Then a new plot is
cleared and the process is repeated. The abandoned plot cannot successfully grow crops for
10 - 30 years. See also slash-and-burn cultivation. |
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Term
slash-and-burn cultivation
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Definition
Cutting down trees and other vegetation in a patch of forest, leaving the cut vegetation on the
ground to dry, and then burning it. The ashes that are left add nutrients to the nutrient-poor
soils found in most tropical forest areas. Crops are planted between tree stumps. Plots must
be abandoned after a few years (typically 2 - 5 years) because of loss of soil fertility or
invasion of vegetation from the surrounding forest. See also shifting cultivation. |
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Term
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Definition
| Methods used to reduce soil erosion, prevent depletion of soil nutrients, and restore nutrients already lost by erosion, leaching, and excessive crop harvesting. |
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Term
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Definition
Movement of soil components, especially topsoil, from one place to another, usually by wind,
flowing water, or both. This natural process can be greatly accelerated by human activities
that remove vegetation from soil. |
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Term
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Definition
Planting regular crops and close-growing plants, such as hay or nitrogen-fixing legumes, in
alternating rows or bands to help reduce depletion of soil nutrients. |
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Term
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Definition
Supplementing solar energy with energy from human labor and draft animals to produce
enough food to feed oneself and family members; in good years enough food may be left over
to sell or put aside for hard times. Compare industrialized agriculture. |
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Term
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Definition
Method of growing crops and raising livestock based on organic fertilizers, soil conservation,
water conservation, biological pest control, and minimal use of nonrenewable fossil-fuel
energy. |
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Term
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Definition
Planting crops on a long, steep slope that has been converted into a series of broad, nearly
level terraces with short vertical drops from one to another that run along the contour of the land to retain water and reduce soil erosion. |
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Term
traditional intensive agriculture
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Definition
Producing enough food for a farm family's survival and perhaps a surplus that can be sold.
This type of agriculture uses higher inputs of labor, fertilizer, and water than traditional
subsistence agriculture. See traditional subsistence agriculture. Compare industrialized
agriculture. |
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Term
traditional subsistence agriculture
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Definition
Production of enough crops or livestock for a farm family's survival and, in good years, a
surplus to sell or put aside for hard times. Compare industrialized agriculture, traditional
intensive agriculture. |
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Term
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Definition
Consuming insufficient food to meet one's minimum daily energy needs for a long enough
time to cause harmful effects. Compare malnutrition, over nutrition. |
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Term
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Definition
Saturation of soil with irrigation water or excessive precipitation so that the water table rises
close to the surface. |
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Term
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Definition
Row of trees or hedges planted to partially block wind flow and reduce soil erosion on
cultivated land.
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