soil erosion
Soil erosion is a gradual process that occurs when the actions of water, wind, and other factors eat away and wear down the land, causing the soil to deteriorate or disappear completely. Soil deterioration and low quality of water due to erosion and run off has often become a severe problem around the world. Many times the problems become so severe that the land can no longer be cultivated and is abandoned. The key to minimizing soil erosion and saving the farm lands is the farmer himself. Ultimately, he is the one who must reduce the level at which erosion sediments are dislodged from his cropland. This program will discuss the erosion process, its effects on crops and the environment, and the Best Management Practices that can be implemented to limit or contain soil movement from the land.Soil erosion can be divided into two very general categories: · Geological erosion: Geological erosion occurs where soil is in its natural environment surrounded by its natural vegetation. This has been taking place naturally for millions of years and has helped create balance in uncultivated soil that enables plant growth. A classical example of the results of geological erosion is the Grand Canyon.
OTHER SOURCES OF INFORMATION: Environment, water/hydrology, soil andagricultural agencies, FAO, IGA, ISRIC, ISSS, UNEP. RELATED ENVIRONMENTAL AND GEOLOGICAL ISSUES: Land degradation. Deposition of eroded soil particles with sorbed contaminants can endanger entire ecosystems along continental margins, in estuaries, wetlands and bottomlands, and on other areas of low slope angle. Soil erosion both affects and is affected by vegetation and crop ------------------------------------------------------------------------ When runoff occurs, less water enters the ground, thus reducing crop productivity. Soil erosion also reduces the levels of the basic plant nutrients needed for crops, trees and other plants, and decreases the diversity and abundance of soil organisms. Stream sediment degrades water supplies for municipal and industrial use, and provides an important transporting medium for a wide range of chemical pollutants that are readily sorbed on sediment surfaces. Increased turbidity of coastal waters due to sediment load may adversely affect organisms such as benthic algae, corals and fish. o Gully erosion: Gullies are larger than rills and cannot be fixed by tillage. Gully erosion is an advanced stage of rill erosion, just as rills are often the result of sheet erosion. TYPES OF MONITORING SITES: Representative sites in uplands and bottomlands. caused by rain and poor drainage. Three types of erosion are: HUMAN OR NATURAL CAUSE:Erosion is a fundamental and complex natural process that is strongly modified (generally increased) by human activities such as land clearance, agriculture (ploughing, irrigation, grazing), forestry, construction, surface mining and urbanization. It is estimated that human activities have degraded some 15% (2000 million ha) of the earth's land surface between latitudes 72° N and 57° S. Slightly over half of this is a result of human-induced water erosion and about a third is due to wind erosion (both leading to loss of topsoil), with most of the balance being the result of chemical and physical deterioration. HUMAN OR NATURAL CAUSE: Eolian erosion is a natural phenomenon, but the surfaces it acts upon may be made susceptible to active wind shaping and transport by human actions, especially those, such as cultivation and over-grazing, that result in the reduction of cover vegetation. Osterkamp, W.R. & S.A.Schumm 1996. Geoindicators for river and river-valley monitoring. In Berger, A.R. & W.J.Iams (eds). Geoindicators: Assessing rapid environmental changes in earth systems :83-100. Rotterdam: A.A. Balkema (see also paper by Lancaster).
Some common words found in the essay are:
THRESHOLDS Sediment, DESCRIPTION Erosion, Grand Canyon, EROSION Soil, THRESHOLDS Gully, MEASURE MENTStandard, ISSUES Land, NATURAL CAUSEErosion, FUTURE Knowledge, SIGNIFICANCE Soil, soil erosion, wind erosion, rill erosion, sheet erosion, gully erosion, water erosion, universal soil loss, osterkamp wr, department agriculture, universal soil, vegetation cover, soil loss equation, revised universal soil, vigil network means, network means observing,
Approximate Word count = 2293
Approximate Pages = 9 (250 words per page double spaced)
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