Erosion and ecology in semi-arid spain (basin of mula, murcia)

Abstract

In recent years the investigation of soil erosion in semiarid environments has concentrated on the controls on runoff and sediment production on hillslopes. A key facter in these controls is vegetation. In this research proyect we seek to establish the relationships between vegetation cover and erosional processes through the effects of interception, litter production and ground cover and other hydrological effects. We have established an experimental plot on marls about 30 km. from Murcia and soil moisture, litter production, runoff and sediment yield are being regularly monitored and observed after temporal variations in the main parameters and to provide inputs to a theoretical model of erosion on the slope. Preliminary results are presented for infiltration curves and these show a very clear destruction between unweathered marls, weathered marls, stone-covered marls and vegetated marls. The first observations of sediment yields, for only two storms, have a poor relation to standard models and indicate the need for a m ove careful consideration of the vegetation cover.