Soils are the main terrestrial reservoir of organic carbon, nitrogen and phosphorus. Thus, any type of disturbance, e.g. landuse changes, that alters soil integrity is a threat to planetaryscale biogeochemical cycles that sustain the life-support systems of the Earth. Soil erosion impacts the residence time of these elements (carbon, nitrogen, phosphorus) in soils, as well as their flux rates, storage and distribution.
Soil erosion is the removal, transport and deposition of soil particles by water or wind from their original place to another location. Factors that influence soil erosion are topography (slope steepness and length), soil erodibility (determined by properties such as texture, structure, moisture, organic carbon content, etc.), vegetation cover and management practices. When soil is left bare, the fine, carbon- and nutrient- rich fractions are removed first, altering physical, chemical and biological soil properties, such as soil albedo, temperature, evapotranspiration, water holding capacity and soil biodiversity at a variety of scales, which disrupt ecosystem functioning. Recent scientific insights, however, place soil degradation, including erosion, in a broader perspective. Soil erosion is not only a biophysical factor but also a feedback component in complex socio-environment systems that disrupts fundamental ecosystem services and the human economic systems that rely on them.
--- World Atlas of Desertification