Revealing various change characteristics and drivers of ecological vulnerability in the Luan river basin based on the SRP model

As a vital ecological barrier and water source for the Beijing-Tianjin-Hebei (BTH) region, the Luan River Basin (LRB) plays a crucial role in maintaining regional ecological balance. However, comprehensive research on Ecological Vulnerability (EV) evaluation in the LRB remains scarce, making EV evaluation and forecasting particularly significant. This study evaluated EV dynamics (2002-2022) via the SRP model with 17 indicators, with driving factors analyzed via Geodetector and 2032 scenarios forecasted by CA-Markov. Key findings revealed: (1) EVI increased from 0.397 to 0.428 (peak at 0.445 in 2017), with Microscopic vulnerability dominating (46.47% average area). (2) Spatially, EV exhibited a "low-medium-high" gradient (lower in northwestern high-altitude areas and higher in southeastern plains), confirmed by significant clustering (Global Moran's I = 0.889-0.938, p value < 0.001). (3) Geodetector identified elevation (q = 0.855), biological abundance (q = 0.812), annual temperature (q = 0.800), and cultivated land proportion (q = 0.783) as primary driving factors. (4) CA-Markov forecasts for 2032 indicate declines in Potential vulnerability (- 5.83%), Microscopic vulnerability (- 2.01%), and Severe vulnerability (- 2.30%), but increases in Mild vulnerability (+ 6.57%) and Moderate vulnerability (+ 3.57%). These findings provide a scientific basis for evidence-based ecological policies in the LRB, contributing to the promotion of regional sustainable development and the balance between ecological conservation and economic growth.