Current status and medium- and long-term variation of soil erosion by water in China

Abstract

Soil erosion is the primary factor causing the loss of soil resources and land degradation. Clarifying the current status of soil erosion in China and the characteristics of future changes under different pathways of development is important to the global management of soil resources, food security, and ecosystem services. We used the revised universal soil loss equation and the most recent and reliable soil and environmental data to characterize soil erosion in China at present and under typical Shared Socioeconomic Pathways and Representative Concentration Pathways (i.e., SSP1–2.6 and SSP5–8.5) in the medium- and long-term future (2050 and 2100). The current average rate of soil erosion in China was 14.78 t ha^-1 yr^-1, with a total amount of about 14.0 Pg yr^-1. The amount of total erosion increased by 5.0 %, 10.8 %, 9.9 %, and 25.9 % for scenarios 2050_SSP1–2.6, 2050_SSP5–8.5, 2100_SSP1–2.6, and 2100_SSP5–8.5, respectively, compared to the baseline amount in 2010. The contribution of climate change and land use to the increase in erosion ranged from 9.5 % to 31.5 % and -6.95 % to -1.78 %, respectively, with the contribution of climate change about 2.36- to 7.54-fold larger than the contribution of land use. Converting arable barren land into forest and grassland or adopting conservation tillage practices for farmland, could nevertheless effectively offset the increase in erosion under the four future scenarios. This study provides data and a scientific basis for managing soil erosion in China and provides a useful reference for conserving global land resources and formulating policies to cope with climatic and environmental changes.