Estimation of Factor C to predict Soil Erosion in the Aguada Blanca Reservoir Basin – Arequipa Peru

Soil loss due to erosion is a serious problem in the western slope of the Peruvian Andes, it is lost can be estimated through the universal equation of soil loss (USLE) and depends directly on the parameters used in the equation. One of the fundamental parameters in the equation is the "C" factor that represents the effects of the vegetation and other coverage of the basin. The objective of this study is the determination of factor C, calculated based on the vegetation cover obtained from the NDVI of Landsat satellite images of 2014 for the basin contributing to the Aguada Blanca - Arequipa reservoir. It was calibrated by measurements with millimetric rules installed in the field, obtaining r2> 85%. The coefficients of the resulting factor "C" are: C = 0.51 for unimpressive cover, C = 0.46 for open grassland, C = 0.29 for pajonal and predominant of Calamagrostis - Stipa, C = 0.22 for Andean grassland with predominance of Parastrephia lepidophylla and C = 0.01 for bofedales. Applying the USLE equation with these coefficients, 145.50 t / ha / year and 128.96 t / ha / year for 2014 and 2001 images.

Key words: universal equation of soil loss, erosion, standardized difference vegetation index, erosion model.