Determination of Cover-Crop Management Factor (C) for Selected Sites in Imo State Using Remote Sensing Technique and (GIS)

Abstract

Human interference through various activities such as road construction, mineral exploration, lumbering, excavation and rural-urban migration has placed a high demand on the availability of land for agriculture and exposed croplands to extensive degradation and erosion. This study therefore aims at determining the cover-crop management factor (C) for selected sites in Imo State representing different soil groups by the use of remote sensing (RS) and geographical information system (GIS) tools. Satellite Images of the study area were analyzed using ArcGIS 10.1 software on a raster distribution array to generate maps for normalized differential vegetative index (NDVI), Land use land cover (LULC) and crop-cover management factor (C). From the maps generated for NDVI values for the sites were between -0.1035-0.386 and the C-factor values were between 0.33-1.34, thus placing the study area within a region of medium vegetative cover. The location with the lowest NDVI was Okigwe while the highest NDVI value was observed in Ohaji. Though the area lies within the tropical rainforest zone, the vegetation is unevenly distributed thereby creating an enabling environment for soil detachment and sediment transport through runoff from heavy downpours resulting from absence of soil surface resistance. The C-factor values obtained therefore encourages tree planting exercises, forest regeneration activities, shrub development and balanced vegetation maintenance so as to create limited soil surface to encourage soil erodibility and runoff so as to allow agricultural activities which will guarantee food security and sustainable environmental management.