Development of GIS-based FUSLE model in a Chinese fir forest sub-catchment with a focus on the litter in the Dabie Mountains, China

Land use plays an important role in soil loss and other environmental problems. Correct prediction of soil loss from different types of land use is very important to land use policy making in the Dabie Mountains, China. Field observations of water and soil loss were carried out in the Shangshe catchment in four types of land use in 1999-2002. This paper reports the study of soil loss in the sub-catchment of Chinese fir forest. Field observations of water and soil loss were carried out at micro-plot scale, Universal Soil Loss Equation (USLE)-plot scale and the sub-catchment scale in the sub-catchment of Chinese fir forest. Analysis of these field observation data shows that litter in forest has important hydrological function. In the Chinese fir forest, the micro-plot without litter and grass produced 71 times soil loss of that from a micro-plot with litter and grass at the same gradient in 2000. By integrating a linear regression method with GIS and USLE, an USLE in forest with a focus on litter (FUSLE) model was developed to predict soil loss in forest. Rain erosivity factor is turned into modified rain erosivity factor when litter is added as a new factor. These measures are believed more practical in soil loss prediction in forest because the litter factor shows the real scenario of soil loss in the forest. Further more, the meter scale plot method is able to get enough field observation data in a few years for soil loss prediction and it is less expensive. (c) 2008 Elsevier B.V. All rights reserved.