ABSTRACT
Soils are indeed initially formed by a process of slow natural erosion over thousands of years, but they can be damaged by heavy rain or wind erosion almost in a matter of hours. The erosion potential of any soil is a function of its structure, the land topography and the weather to which it is subjected. Surface weather conditions tend to alter fairly rapidly with situation, and so it is appropriate to consider questions of site and general topography. Weather conditions, and hence the climate, change rapidly with increase in height above sea level, both in the air and in the soil. The altitude of any field is therefore an important factor in regard to the combined effects of soil and weather. Evaporation from the soil and transpiration from plants decrease with height, but on the other hand the rainfall is greater at higher levels.
