Integrating LULC and ecosystem services into multi-scale ecological security assessment and management zoning in fragile mountainous regions

Ecological security (ES) is a crucial indicator of regional ecosystem health and integrity, serving as a fundamental basis for formulating sustainable ecological management strategies, particularly in ecologically fragile regions. This study developed a multi-scale assessment framework based on the Pressure-State-Response (PSR) model, integrating land use and land cover (LULC) structure and ecosystem service capacity, to evaluate the spatiotemporal dynamics and drivers of ES in the Wuling Mountainous Region from 2000 to 2020. Regional ES showed an overall upward trend, with the mean value increasing from 0.1070 to 0.1294. Very insecure areas decreased by 66.27%, whereas very secure areas increased by 111.66%. At the county scale, relatively secure and very secure counties increased from 18 to 35, with their total area expanding by 90.43%. Spatially, ES exhibited a persistent east–west gradient, with higher levels in the central and eastern continuous forest landscapes and lower levels in the northwestern and southeastern margins. Spatial patterns were consistent across both grid and county scales. Geodetector analysis indicated that ES variation was primarily associated with LULC structure and ecosystem service capacity. The proportion of cropland area, habitat quality, land-use intensity, and soil organic carbon exhibited the highest explanatory power, whereas socioeconomic factors showed weak and declining direct effects, indicating that their influence is primarily mediated through LULC changes. Based on the multi-scale assessment, 412 subbasins were classified into four ecological management zones to support differentiated governance in mountainous systems.