What is Erosion?

'Erosion is the wearing away of the land surface by rain or irrigation water, wind, ice or other natural or anthropogenic agents that abrade, detach and remove soil from one point on the earth’s surface and deposit it elsewhere.' (Glossary of Soil Science Terms. Soil Sci. Soc. Am. 1997) 

Soil erosion is a global problem. Erosion of soil can contribute to instability in a region because of inability to produce adequate food and fiber. (see article - Soil Erosion as Big a Problem as Global Warming Say Scientists. (pdf)). In the U.S., the cost of water and wind erosion each year is estimated in billions of dollars. This high cost is attributed to erosion removing the upper soil layer from lands and subsequently reducing their productivity and polluting water and air.