Spatiotemporal Evolution of Ecosystem Service Value in the Yellow River Basin of China: Factor Revision, Driving Forces, and Interactive Effects

The ecological conservation and high-quality development of the Yellow River Basin (YRB) is a major national strategy. Scientifically assessing its ecosystem service value (ESV) and driving mechanisms is a key prerequisite for achieving regional ecological protection and sustainable development. Existing studies predominantly rely on static or locally adjusted equivalent factors, making it difficult to capture the dynamic evolution of ESV in response to changes in ecosystem structure and socio-economic conditions. Moreover, there is a lack of quantitative analysis on the interactive driving mechanisms behind the spatial differentiation of ESV. To address this, this study establishes a dynamically adjusted ESV equivalent factor framework based on localized parameter calibration, conducting multi-period dynamic accounting of ESV in the YRB from 2000 to 2020. Combined with the geographical detector model, it identifies the dominant driving factors of ESV spatial differentiation and their interactive effects. The results show: ① From 2000 to 2020, the overall ESV of the YRB exhibited a fluctuating growth trend (“rise-decline-recovery”) with an increase of 13.3%. The trends in the upper and middle reaches were generally consistent with the whole basin, while the lower reaches experienced continuous decline with an expanding rate, reflecting a regional differentiation pattern of “improvement in upper/middle reaches and degradation in lower reaches”. ② The spatial distribution of ESV showed a pattern of “higher in the west and south, lower in the east and north.” Hotspots (high-value clusters) significantly contracted, while cold spots (low-value clusters) expanded, with a trend of “expansion in middle/lower reaches and contraction in upper reaches”. ③ Land use type was the primary driver of ESV spatial differentiation. The explanatory power of any two-factor interaction exceeded that of a single factor, demonstrating a two-factor enhancement effect and highlighting the synergistic driving mechanism of natural and socio-economic factors. ④ The interaction between land use and other factors was most prominent but showed a weakening trend, indicating that the spatial differentiation of ESV in the YRB is transitioning from “single strong-constraint driving” to “multi-objective comprehensive dominance”. By dynamically adjusting equivalent factors, this study clarifies the spatial differentiation patterns of ESV under multi-factor interactions and reveals the evolutionary process of ESV in the YRB as “stable pattern-stage differentiation-mechanism transition”. It provides a quantitative basis and decision-making reference for precise spatial governance, optimization of ecological security patterns, and the design of coordinated pathways for ecological conservation and high-quality development in the YRB.