Delineating ecological improvement zones based on impact thresholds of ecosystem health changes in Northwest Hubei, China

• Significant ecosystem health improved under different scenarios in 2040. • Ecosystem health showed inverted “U”-shaped and concave wave-shaped responses to drivers. • Notable reduction in ecological improvement zones occurred in 2040 compared to 2020. • Southeastward shift of ecological improvement zones centers in 2040 relative to 2020. The impacts of different driving factors on ecosystem health involve complex nonlinear response mechanism. Here, we focus on northwest Hubei Province in China, an ecologically sensitive area designated as a national ecological function reserve, and employ a multi-source data and multi-model integration framework to investigate the mechanisms by which different drivers influence ecosystem health. We also delineate zones of ecological improvement under various land cover change scenarios. The research results show that: The Kappa coefficients of land cover prediction under different scenarios in 2040 are above 0.9. The nonlinear relationship between different drivers and ecosystem health, such as inverted “U”-shaped and concave wave-shaped curves, is depicted using constraint lines. Based on this, restricted cubic spline functions were employed to determine the impact thresholds of different driving factors. For example, the DEM threshold in the ecological functional zone1 (BIO-CS synergetic bundle) decreased from 1,160 m in 2020 to 450 m in 2040. And spatial overlay analysis was used to delineate ecological improvement zones (EIZs). Compared with 2020, the centers of EIZs under different land cover change scenarios in 2040 shifted to southeast, and the areas showed a decreasing trend. Among them, the economic development scenario decreased the most, with an area of 1,826.22 km2. This study aims to provide a scientific basis for decision-making in the construction of the regional ecological security pattern.