Soil erosion has occurred for over 450 million years. Erosion is the consequent of displacement of soil, mud, stones, rock and other particles by water, ice, rivers, streams, ocean currents, wind or living organisms. Gravity helps in soil erosion. Erosion is a natural process but time and again is made worse by human in the name of deforestation, overgrazing, over building and building of roads. Excessive erosion leads to damage of the ecosystem, loss of topsoil and water sedimentation. The effects of erosion are made worse due to overpopulation. Soil erosion can be minimized by improved land use techniques such the building of terraces, tree planting, the use of cover crops and minimal deforestation.
Generally soil erosion occurs at the about the same rate as soil is formed, but increased soil erosion at an alarming rate has lead to land left unprotected, exposed and vulnerable. In expanding to man's irresponsible actions, simply occurring rainfalls or windstorms make erosion a huge environmental concern. Erosion occurs in both agricultural and farming areas as well as in the natural environment. Effects of erosion impact 2 places, on-site and off-site.
Tillage erosion occurs with the introduction of today's qualified agricultural equipments. Soil erosion must be studied over short and long-term spans. The main impact of soil erosion is the discount of soil quality. Crops are reliant on the upper topsoil, which is the part most susceptible to erosion from wind and water. The erosion of the topsoil causes loss of nutrient rich upper layers of soil, as well as the discount in water keeping capacity of this eroded soil. Erosion removes the 'cream of the soil'. In affluent countries this qoute is combated with the use of artificial fertilizers and technology but in poorer countries this is not an option. Loss of nutrient rich soil is a long time problem. Globally, the threat to long- term sustainability of agricultural productivity is the moist serious consequence of erosion.
The connection between soil erosion and crop productivity is not an exact science due to the large variability in outcomes. Monitoring the effects on yield is hampered since erosion is a gradual process and its consequent on yield is often obscured. The destructive impact of erosion is well known in developing countries such as Africa and Asia but even in industrialized countries this is also a huge environmental concern. Erosion caused by water is a serious issue in Austria, New Zealand, Eastern and Southern Europe as well as some parts of the Usa.
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