Evaluation of water conservation function of Danjiang River Basin in Qinling Mountains, China based on InVEST model.

With the shortage of water resources becoming a global concern, the water conservation function has become one of the most important service functions and the key factor in the sustainable development of watershed ecosystem. The Danjiang River Basin as an important source of water for the middle route of China's South-to-North Water Diversion Project, its water conservation function has attracted extensive public attention under global climate change. In this study, InVEST water yield model based on Budyko hydrological method was employed to analyze the spatio-temporal dynamics of water conservation, and the response of water conservation to climate, land use and soil changes for the period from 2000 to 2019. The results show that the water conservation of Danjiang River Basin tends to decrease under the comprehensive influence of various factors. The spatial analysis of the importance of water conservation identified Shangnan County, the southern part of Danfeng County and the northern part of Shanyang County as important water conservation areas in the study area, which should be regarded as the key and priority protection areas in the regional water resource and ecological protection. The study provides insights for sustainable water management and ecological protection policies, and the InVEST model with localized parameters can also be applied to other areas lacking climate, hydrological and geological data.