A novel modification framework for evaluating ecosystem service value in China’s five major freshwater lakes and their surrounding cities from 2002 to 2022
Yan Lu, Chi Xu, Xiqian Wang
Abstract
Ecosystem services (ES) are essential for human survival and ecological balance. Ecosystem Service Value (ESV) quantifies ES and aids policy and resource management. However, rapid urbanization and population growth have increased pollution and shrinking areas in freshwater lakes, significantly reducing their ESV. Existing studies mainly focus on single regions and often neglect integration of natural-socio-economic factors, limiting accuracy. We used an innovative equivalent factor method modification framework combining natural and socio-economic dimensions to analyze the spatial–temporal evolution of ESV in China’s five major freshwater lakes from 2002 to 2022. Based on this framework, an XGBoost-SHAP nonlinear model was used to explore the driving mechanisms. The results indicate that: (1) From 2002 to 2022, ESV followed a trend of ‘increased, then decreased, but grew overall’, with Poyang, Dongting, Taihu, Hongze and Chaohu Lakes seeing increases of 4.62, 2.16, 3.32, 2.18 and 0.66 billion CNY, respectively; (2) Medium- and high-grade ESV zones exhibited an ‘increased, then decreased, but grew overall’ pattern, with water bodies consistently showing high ESV; (3) Population density (PD), net primary productivity (NPP) and normalized difference vegetation index (NDVI) are key factors influencing freshwater lake ESV variability, with impact values concentrated between −0.1 and 0. (4) ESV in Poyang and Dongting Lake is primarily driven by NPP and NDVI , while other lakes are more influenced by PD. These findings support the sustainable management of freshwater lakes and the coordinated optimization of ecological conservation and social-economic development.