Quantification of surface water erosion in semi-arid hillsides of the Peru Sierra

At the Peruvian Highland, a research was conducted over 22 micro watersheds in the highlands of 12 regions with the objective of quantify the soil lost due to water erosion and the impact of the construction of erosion control infiltration ditches. The research area is a semi-arid zone with rugged topography and with an average annual rainfall that varies from 350 to 1200 mm/year. Social characteristics of this region are the highest rates of poverty and extreme poverty and high rates of water erosion. The results found indicate that the average rate of erosion on the slopes of the mountain is about 45.04 tons/ha-year, which represents a soil lost layer of 3.20 mm/year. There was also found that the construction of infiltration ditches, reduced soil loss in 20.60 tons/ha-year, which means a layer of 1.47 mm/year. These results are very useful, since the soil loss was quantified for the first time and they will help for planning soil conservation works to be done in this important region of the country.