Author(s): Yangwen Jia; Hui Peng; Cunwen Niu
Keywords: Eco-hydrological model; Water and soil conservation; Loess Plateau
Abstract: The Loess Plateau of China is ecologically vulnerable region due to serious soil erosion and strong impacts of human activities. Study on the interaction of ecological and hydrological processes in the region is of important theoretical meaning and practical application value to ecosystem protection and water resources management. In this study, we developed a distributed eco-hydrological model to simulate and predict hydrological and vegetation growth processes by coupling a vegetation ecosystem model, BIOME-BioG eoC hemical Cycles (BIOME-BGC) and a distributed hydrological model, Water and Energy transfer Processes in Large river basins (WEP-L). BIOME-BGC updates the vegetation parameters of WEP-L in a daily time step, and WEP-L provides hydro-meteorological data to BIOME-BGC. To obtain vegetation growth data, we carried out on-site ecological observation using photosynthesis apparatus. We applied the eco-hydrological model to the Jinghe River basin (45421km 2) of the Loess Plateau. The model validation shows that the simulated results have good agreement with the field observation data or literature values of Leaf Area Index (LAI), Net Primary Production (NPP) of vegetation and river discharge. For future water and soil conservation measures, five scenarios based on land use changes were used for the eco-hydrological model to predict eco-hydrological response in the Jinghe River Basin. Results show that under the water and conservation measures impact, the average annual and flood season discharge may decrease, the average annual NPP may increase, and Net Ecosystem Production (NEP) may decrease. This means a big challenge to the water resources management in the basin and adaption measures are desired to be worked out.