Identification and Optimization of Ecological Network in Arid Inland River Basin Using MSPA and Spatial Syntax: A Case Study of Shule River Basin, NW China

Habitat fragmentation has become an important factor in the reduction of biodiversity. Identifying and optimizing ecological networks (ENs) can help alleviate the negative impact of habitat fragmentation and improve regional biodiversity. Taolai River Basin is an inland river basin in Northwest China. Due to the impact of climate change and human activities, there are many ecological problems such as grassland degradation and shortage of water resources. It is urgent that we identify and optimize the EN. This study comprehensively uses morphological spatial pattern analysis (MSPA), the minimum cumulative resistance model (MCR), and circuit theory to identify ENs, evaluates ENs based on Spatial Syntax, and determines the protection priority of ENs, then diagnoses ecological “pinch points” and ecological obstacles by combining remote sensing and GIS spatial analysis methods. The results show that: (1) the ecological source area of the basin is 3061.63 km2, with uneven spatial distribution, mainly distributed in the Qilian Mountains in the south of the basin; (2) there are 106 ecological corridors in the basin, with a total length of 2267.30 km and an average length of 21.38 km, which is not conducive to species migration; (3) the optimum widths of ecological corridors in the south, middle, and north of the basin are 100 m, 60 m, and 300 m, respectively; (4) the key areas of watershed ecological restoration include the “pinch area” between the southern core area and the central core area and 108 ecological barrier points; and (5) combined with the spatial characteristics of various key areas of ecological protection and restoration, the spatial pattern of “one core–four rings–five belts” of watershed EN construction is obtained.