Evaluating the Impacts of Climate Change on Soil Erosion Rates in Central Mexico

Abstract

Although water-eroded soil (WES) resulting from human activities has been recognized as the leading global cause of land degradation, the soil erosion risks from climate change are not clear. Studies have reported that WES is the second most significant cause of soil loss in Mexico, and its future trajectory has not been sufficiently evaluated. The aims of this study are to 1) determine the impacts of climate change on WES and its distribution for the State of Aguascalientes, Mexico, and to 2) compare the present and future soil loss rates for the study unit (SU). The State of Aguascalientes is located in the “Region del Bajio.” The impact of climate change on WES was evaluated using the near-future divided world scenario (A2) presented in the IPCC Fourth Assessment Report. Daily temperature and precipitation data from 18 weather stations were downscaled to model historic laminar water erosion (HLWE) and changes therein in the A2 near-future scenario for 2010–2039 (LWEScA2). Due to future changes in mean annual rainfall (MAR) levels, a change in the LWEScA2 of between 1.6 and 8.9% could result in average soil losses up to 475.4 t ha-1 yr-1, representing a loss of slightly more than a 30-mm layer of mountain soil per year. The risk zones, classified as class 4 for LWE, are located to western of the State in part of municipalities of Calvillo, Jesus Maria, San Jose de Gracia y Cosio, where there are typical hills and falls with soil very sensitive to rain erosion.