Simulated impacts of climate and land‐cover change on soil erosion and implication for the carbon cycle, 1901 to 2100

Abstract

The impacts of climatic change and land‐cover change on soil carbon displacement by water erosion were investigated using a global ecosystem carbon cycle model (Sim‐CYCLE) and an empirical erosion model (RUSLE). Simulations considering the climate and land‐cover changes were performed in two phases, from 1901 to 1990 on the basis of historical data, and from 1991 to 2100 using climate projections in the IPCC Forth Assessment Report. During the first phase, total lateral displacement of soil carbon was estimated to be 1.6 ± 0.1 Pg C y−1 with remarkable geographical heterogeneity, and it was gradually intensified in regions where forests were converted into croplands. During the second phase, both projected rainfall and land‐use changes affected the erosion regime in many regions. Consequently, the total amount of soil carbon displacement increased by 32–57%, implying an intensified vulnerability to soil loss and further perturbations in the carbon cycle.