Unveiling ecosystem service dynamics under land use/cover changes in a plateau lake basin: a trajectory-scenario coupled approach

Accurately assessing the dynamic response of ecosystem service values (ESV) to land use/land cover (LULC) change is fundamental to sustainable spatial planning in sensitive plateau lake basins. However, conventional assessment methods often fail to capture the cumulative effects of these changes, thereby limiting their practical utility. To address this limitation, we developed a “trajectory-scenario coupled” framework, focusing on the Fuxian Lake Basin (FLB) in China as a case study. This approach integrates an improved stable mapping method to reconstruct the historical evolutionary pathways of ESV from 2005 to 2020 and employs the Markov-PLUS model to simulate future scenarios for 2035 under four distinct policy-driven scenarios. Historical analysis revealed that the total ESV exhibited a “decline-recovery-stabilization” trend, with 89.73% of the area remaining stable. Spatially, ESV losses were concentrated around the lake, primarily driven by the conversion of cultivated land to construction land. Future scenario simulations demonstrated that an ecological conservation strategy could significantly enhance ESV, whereas an economic development pathway would lead to its severe degradation, highlighting the pivotal role of conservation policies. Ultimately, by fusing historical trajectories with future projections, we delineated targeted ecological conservation, control, and risk zones, providing a robust decision-support tool for managing sensitive ecosystems.