Mapping gully erosion in Abia State, Nigeria using Geographic Information Systems (GIS) and remote sensing techniques

Abstract

Soil erosion is of major concern in Abia State, Nigeria. This study adopts a combination of Geographic Information Systems (GIS) and Remote Sensing as a tool to study and map soil erosion menace in Abia State. For this research, several datasets that represent climate, soil, geology, topographic and anthropogenic factors were used as the basic requirements for environmental modeling of soil loss using Universal Soil Loss Equation (USLE) for 1986 and 2003. The results show that 1082.58 tons/acres were lost in 1986 and 1120.59 tons/acres in 2003 in the study area. Also, a negative correlation was found to exist between soil loss and NDVI (Normalized difference vegetation index) value. Soil erosion vulnerability index map as well as risk prone areas maps was produced. This study shows the integration of GIS with remote sensing as an efficient and effective tool in the study and mapping of soil erosions.

Gully Erosion and Landslides in Southeastern Nigeria: Causes, Consequences and Control Measures

“…Several authors have applied mathematical and predictive models to determine rate of soil losses and erosion processes [28][29][30][31][32]. The Universal Soil Loss Equation (USLE) is a mathematical model used to describe soil erosion processes [28,29] in an area.…”

“…Therefore, the greater the length of slope of a field the greater the concentration of water and run off. A Digital elevation Model data (DEM) if used together with ArcGIS tools, flow direction and flow accumulation of the study area can be computed[30]. The equation used for computing slope length is: Slope steepness factor: S factor is the slope steepness factor.…”

Soil Vulnerability Assessment of Afikpo South Local Government Area, Ebonyi State, Nigeria

“…The slope length factor determines the concentration of water. The greater the slope length of a field, the greater the concentration of water and runoff [13]…”