Ecosystem service value under changing land use in rocky mountainous area of Northern China: spatiotemporal evolution and driving mechanism

The Yihe River Basin (YRB) is a typical rocky mountainous area in northern China, where decades of human activities have significantly altered land use, affecting landscape patterns and ecosystem service value (ESV). These transformations have profound implications for regional ecological integrity and the sustainable development of socio-economy systems. This study seeks to quantitatively assess ESV in the YRB and to investigate its spatiotemporal heterogeneity, as well as the factors influencing these variations. Utilising the revised equivalent factor (REF) method, this research evaluated ESV in the YRB from 1975 to 2020. Furthermore, the study employed optimal parameters-based geographic detector (OPGD) model to identify the primary driving factors affecting ESV. The findings indicated that ESV showed a fluctuating upward trajectory, increasing from 33.37 billion CNY in 1975 to 33.81 billion CNY in 2020, with regulating services comprising 54.14 % of the total value. Spatial analysis showed that ESV initially increased then declined with altitude, whereas hot spots were mainly located near mountains and reservoirs. Key land use types, namely forest land, grassland, and water body, significantly influenced ESV, while anthropogenic activities were the primary drivers of changes in ESV within the YRB. Land use intensity (LUI) proved to be more influential than climatic factors. Positive interventions related to LUI, along with natural factors, contributed to enhancing ESV. Therefore, it is essential to develop and implement scientific land use policies. Efforts should prioritize forest land and grassland protection, restrict overdevelopment, and promote ecological restoration to enhance ecosystem services and sustain the YRB landscape.