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The soiling loss represents the fraction of energy lost due to soiling. The soiling deposition rate (or soiling rate ) is the rate of change of the soiling loss, typically given in %/day. Note that most sources define the soiling rate to be positive in the case of increasing soiling losses' [ 1 ] [ 17 ] [ 18 ] but some sources use the opposite ...
The Act also gave directives to conserve the soil in the "high plains"—soil that was being raised into huge dust bowls during the 1930s. This period, known as the Dust Bowl, coupled with the economic hardships of the Great Depression, hit farmers particularly hard. The act attempted to correct earlier government policy that encouraged farmers ...
The rows formed slow surface water run-off during rainstorms to prevent soil erosion and allow the water time to infiltrate into the soil. Soil conservation is the prevention of loss of the topmost layer of the soil from erosion or prevention of reduced fertility caused by over usage, acidification, salinization or other chemical soil contamination
[11] [12] Soil degradation is a gradual process involving the natural and anthropogenic processes that result in the physical loss (erosion) and reduction in soil quality. [7] The recognition of anthropogenic effects on soil degradation has influenced discourse of urban soil management, and formulation of policies by regional organizations. [13]
Soil can be over-irrigated due to poor distribution uniformity or management wastes water, chemicals, and may lead to water pollution. Over-irrigation can cause deep drainage from rising water tables that can lead to problems of irrigation salinity requiring watertable control by some form of subsurface land drainage .
The controls often involve the creation of a physical barrier, such as vegetation or rock, to absorb some of the energy of the wind or water that is causing the erosion. They also involve building and maintaining storm drains .
Soil erosion is the main factor for soil degradation and is due to several mechanisms: water erosion, wind erosion, chemical degradation and physical degradation. Erosion can be influenced by human activity. For example, roads which increase impermeable surfaces lead to streaming and ground loss.
A problem with no-till farming is that the soil warms and dries more slowly in spring, which may delay planting. Harvest can thus occur later than in a conventionally tilled field. The slower warming is due to crop residue being a lighter color than the soil exposed in conventional tillage, which absorbs less solar energy.