Investigating erosion rates and processes within Japanese forests using fallout radionuclides

Abstract

In Japan, soil erosion represents an important threat to the longer-term sustainability of Japanese cypress plantations. To confirm the dominant erosion process operating in a Japanese cypress plantation catchment, we predicted the sediment transport capacities of both overland flow, expressed as a function of the upslope contributing area and the local slope gradient, and rainsplash for 45 sampling points across the catchment. The results indicated a close correspondence between the local transport capacity of overland flow and the local erosion rates estimated using the radionuclide measurements, but there was no significant correlation between the topographic curvature and the erosion rates.