A DETERMINATION OF THE REVISED UNIVERSAL SOIL LOSS EQUATION (RUSLE) PARAMETERS FOR SOIL ERODIBILITY IN PARTS OF EASTERN NIGERIA.

Abstract

Soil Erosion is ravaging most parts of eastern Nigeria and the pressure on the land for infrastructural development is ever increasing and may not ease in the foreseeable future thus a study was carried out to determine the susceptibility of soils in some parts to erosion with a view to develop regional scale maps and identify combinations of soils, landforms and land cover that may respond to climate variability. The Revised Universal Soil Loss Equation (RUSLE) and Geographic Information System (GIS) were used to study the soil erodibility of the area. Field and laboratory investigations were carried out in line with American Standard for Testing and Materials (ASTM) D422-72:1984 procedures. The results obtained from the investigations, land use and land cover classifications as well as topographical maps were digitized in a GIS environment to determine the Actual soil losses. The actual soil eroded within the study area is 1725.13t/ha/yr. The results suggest that about 7.48% (243.04km²) of the area is very susceptible to soil erosion. The cover practice significantly reduced the high risk of erosion to moderate and manageable level. Adequate precaution is therefore necessary if the ground cover (vegetation) is to be disturbed for any form of development especially in the high risk areas where the erosion rate is above 30 tons/ha/year.