Water-and sediment-yield assement in an area of degraded Caatinga

Abstract

The Caatinga is a biome that is vulnerable to desertification, where the occurrence of excessive runoff and erosion should be reduced. Vegetation thinning is a common practice in Caatinga, but its environmental impacts are not thoroughly known. The objective of this research was, therefore, to assess runoff and erosion in plots of both thinned and preserved Caatinga, comparing their results. For this purpose, two plots (3m x 30m) have been monitored for two years with both natural and artificial on-site precipitation. The conclusions were that, for the experimental facilities, no statistical difference was found between the two treatments, either concerning water or sediment yield. The reason for the high performance of the thinned Caatinga was the presence of herbaceous vegetation. However, thinned Caatinga is more vulnerable than preserved Caatinga towards degradation because of its usual association with livestock, which increments runoff and, therefore, erosion.