Soil erosion, the most widespread and severest of natural calamities, through its invidious attack on the entire agricultural economy of the land, is intimately related to the geography of the place. Soil, as a definite element in the physical milieu of man, is the fundamental basis of three distinct types of ecological processes-agricultural, pastoral and nemoricultural, of which the former constitutes the main occupation of the majority of human race living on the earth.
Soil erosion, the gravest of the natural menaces to the agriculture of a country, thus becomes a vital issue in the geographical problem of the land. Further, as will be seen later, erosion; processes over the surface of the earth are governed by definite geographical elements of Nature and as such geographic research in the domain of agriculture, soil erosion, and soil conservation constitutes one of the primary steps in the national reconstructive programme of a nation.