Spatiotemporal pattern of wind erosion on unprotected topsoil replacement sites in Mainland China

Abstract

Topsoil is required to be stripped and reused to maintain land productivity in mining and construction activities. However, as a great threat to unprotected soil, wind erosion on topsoil replacement sites has not received enough research attention, which hinders the efficient implementation of wind erosion control measures in the right time and place on a national scale. This study aims to evaluate wind erosion on unprotected topsoil replacement sites (WEUTRS) in mainland China, examining its spatiotemporal pattern and demonstrating its significance for the relevant research and industry. The WEUTRS was calculated by the Revised Wind Erosion Equation with meteorological data (1988-2017) and raster data of soil properties. The results showed a strong spatiotemporal heterogeneity of WEUTRS. The highest (>300 kg m-2) and the lowest (<0.5 kg m-2) WEUTRS appeared in Northwest and Central Southern China, respectively. The most drastic temporal change through the year was in Northwest China (as high as 335.4 kg m-2 on the example site), followed by Qinghai-Tibet Plateau and Shandong Province. By contrast, almost no temporal changes happened in Central Southern China. The ratio of monthly WEUTRS to respread the topsoil mass (Rw) in Northwest China and Mongolia Plateau reached 10% or more in specific months, and less than 0.1% in most of Southern China. The WEUTRS quantification could be applied to the wind erosion control on topsoil replacement sites on both a national scale and a regional scale. The spatiotemporal pattern of WEUTRS may be a scientific basis for a nationwide or regionwide differentiated policy on the wind erosion control on topsoil replacement sites for policy makers, as well as the reference to the proper working schedule and the control measures for local mining and construction projects for management authorities and practitioners.