Determination of Slope of Enugu for Erosion Models

Slope in soil erosion models (soil loss equations) refer to slope components known as the LS factor. Generating the LS values poses the largest problem in using the Universal Soil Loss Equation (USLE). This work gives the practical solution to slope determination using two methods; the direct field measurement and the topomap techniques. From direct field measurement technique, slope was ascertained by excavation of the study area and measurement of the selected vertical distance (rise) over a selected horizontal distance (run), which was used for the determination of the slope length and gradient (angle) using the general slope equations. Using the topomap method, point A and B were identified on the map sheet, the elevations of point A and B were obtained from the contour lines while the distance of the two points were obtained from the map using a meter rule and the map scale. The values of their elevations (rise) over their distances (run) were used to compute slope length which was useful in obtaining slope angle. Either way, the values of L and S were multiplied together to generate a single value known as the LS factor which is applicable in the Universal soil loss equation and other erosion models to be developed in the area in future years. These models can be used to calculate and predict soil erosion occurrence in the study area; Enugu State of Nigeria. Slope management techniques to minimize erosion were also prescribed as a prevention strategy rather than remediation of eroded soil.