ABSTRACT
The importance of the soil arises from the following considerations: Soil is a natural resource, necessary for plant growth, Erosion of the soil leads to environmental degradation and therefore needs to be controlled, Soil is a source of the sediment, Soil acts as a filter for the groundwater, and Soil serves as a bearing material for roads, pipelines, buildings, etc., and as construction material for mud-built houses. Soils are the loose mantle on the surface of the earth. They may be formed in situ from rocks or sediments, or they may be deposited after transport. The texture and structure of a soil determine its porosity, and porosity governs the water-bearing capacity and aeration of the soil. Clay soils contain a relatively high volume of fine pores. They retain a high volume of water but their permeability is low Sandy soils have coarser pores. The distribution and agricultural potential of some important soil types are given.
