Effect of Surface Runoff on Sediment Yield of Some Soils in Gidan Kwano Area of Niger State Nigeria.

Abstract

The process of surface runoff is made possible when the rainfall reaching the soil surface is more than the infiltration capacity, all the water is absorbed into the soil, and as the rain continues, plant surfaces become saturated, the interception-loss rate declines and infiltration capacity is reduced. Thus the detaching soil particles from its parent source which leads to the movement and transportation of soil particles from one point to another. An experimental runoff plot was established with a dimension of 3m by 6m of land was set up in areas where the various types of soil were being considered during the rainy season of the year 2010 with the slope of each of the plots determined. Disturbed sandy soil had the highest soil loss of 0.266kg/m2 while that of the undisturbed sandy soil is 0.192kg/m2 for the month of July. In the month of August, undisturbed sandy soils loss was calculated to be 0.183kg/m2 which shows a reduction in the total soil loss when compared with the month of July which could be due to the fact that most of the top loosed soils have been detached during the first sets of rainfall in the earlier months and also the August break experienced. Disturbed clay soil had the least quantity of soil loss of 0.128kg/m2 while that of the undisturbed clay soil was higher which may be due to the human and animal movement within the area before the plot was set up.