A Spatio-Temporal Study of Land Degradation and Land Use/Land Cover Trends in the Upper Tyume Catchment Using Remote Sensing and Geographic Information Systems

Abstract

The study traced land degradation trends and land use changes and their relationships over time in the Upper Tyume Catchment of the Eastern Cape Province of South Africa. An integrated approach was used to investigate the reasons behind the occurrence of physical land degradation and how land use changes could have influenced degradation. A GIS-based soil erosion potential model and interpretation of aerial photographs (1: 10 000) spanning 47 years (1949-1996) were used to identify areas of differing soil erosion susceptibility. The erosion model used soils, slope, hydrology and land use as variables. Predicting slope areas susceptible to gully initiation was based on a 20m resolution DEM from which slope classes were computed. The modelling results were compared with aerial photo interpretation results and fieldwork.