A Landuse Change and Land Degradation Study in Spain and Greece Using Remote Sensing and Gis

The relationship between landuse/landcover (LULC) changes and land degradation in two Mediterranean sites is investigated using remotely sensed and ancillary data. The areas of study, the Xaló river catchment in the north of the Alicante province in southeast Spain and the Aegean island of Lesbos, Greece, have both been subjected to changes in LULC, such as abandonment, overgrazing, forest fires and tourist development. Landsat MSS data dating back to the 1970s were used for the mapping of historic landuse/cover types whereas Landsat TM and ETM+ data were employed for the analysis of their recent state. A soil erosion model was then used within a GIS in order to study the susceptibility of the areas affected by changes to overland flow and rainsplash erosion. The model consists of four parameters, namely soil erodibility, slope, vegetation cover and overland flow. The results show increased susceptibility to runoff and erosion mostly for those areas were forest fires, urbanization, and/or overgrazing were the main causes of change and suggest that mitigation measures should be taken for the prevention of further degradation. The readily implemented methodology proposed, based on modest data requirements, is a useful tool for catchment to regional scale LULC change and land degradation studies.