Construction and Optimization of Ecological Security Patterns Based on Self-Organizing Map and Multisource Data at Different Scales

Establishing ecological security patterns (ESPs) is essential for protecting regional ecological integrity and guiding land-use optimization. Accurate identification of ecological sources is crucial; therefore, a multiscale identification framework has been proposed to address conventional approaches that homogenize sources and overlook scale-dependent effects. A Self-Organizing Map (SOM) was applied in the Dongting Lake Basin within a dual-scale (grid/sub-watershed) “importance–sensitivity–connectivity” framework. The ecological resistance surface was refined using socio-ecological factors, and circuit theory was used to construct ESPs and generate targeted optimization strategies. Key findings include the following: (a) Ecological sources exhibited similar spatial distributions across both scales, concentrating in western mountainous regions and basin margins, and largely absent from urban areas. Grid-scale sources totaled 38 (45,035.47 km 2 ), compared with 28 sub-watershed sources (92,349.85 km 2 ), with the former showing stronger connectivity. (b) Both scales revealed sparse ecological corridors in central regions; at the grid-scale, 90 corridors (3,779.51 km) were mainly in western areas, whereas 56 optimal corridors (2,256.59 km) were concentrated in eastern areas at the sub-watershed scale. (c) The ecological nodes identified at the grid and sub-watershed scales are 129 and 45. Grid-scale nodes were clustered in the western and southern corridors, whereas the sub-watershed nodes were mostly in the eastern and southern corridors. (d) Spatial optimization frameworks were developed as “one ring, two corridors, three zones, multiple cores” (grid-scale) and “one ring, one corridor, three zones, multiple cores” (sub-watershed scale), guiding conservation planning. This framework integrates functional ecological zoning with holistic governance, providing insights for ecological restoration and sustainable management.