Erosion Types Erosion is the wearing away of the earths surface by the forces of water and wind. It is a natural process which can have striking results, such as the Grand Canyon or the North Dakota Badlands, but most often is a slow, less dramatic process. A large portion of the worlds population gets its food supply from soils formed as a result of natural geologic erosion. When the natural landscape is disturbed by activities of man such as tillage, timber harvesting, or over grazing, erosion can become accelerated and destructive. Healthy productive soil is lost and sediments damage or clog water bodies, rivers, streams and reservoirs.
Erosion is divided into two main categories, water and wind.
Suspension very fine soil particles are lifted from the surface by the impact of saltation and carried high into the air, remaining suspended in the air for long distances. These erosion prediction models are used to estimate water and wind erosion on several land uses. Classic and ephemeral gully erosion and stream bank erosion are not included in NRI erosion estimates, but may cause significant soil loss in some areas. Information on USLE and WEQ is found in Agriculture Handbook 537 and the National Agronomy Manual. Additional data are displayed in Table 10 - Average Annual Sheet and Rill Erosion by Year .