Ecological Security Pattern Construction in Hilly Areas Based on SPCA and MCR: A Case Study of Nanchong City, China

Urban expansion is constantly encroaching upon and destroying ecological spaces, and the construction of an ecological security pattern with the goal of ensuring ecological security has become a problem that must be considered during urban development. At present, little attention is paid to hilly cities. In this paper, Nanchong City, a typical hilly city, is selected as the research object, and the classic "source-corridor-node" paradigm is adopted to construct the ecological security pattern of Nanchong City. First, the core ecological protection area is taken as the ecological source. Secondly, the index of the ecological resistance surface is selected, and the weight of the index is determined by using the spatial principal component analysis (SPCA) method to construct the ecological resistance surface. The results show that the area of low-resistance biological migration in Nanchong City equals 854 km(2), which accounts for 6.86% of the total area. Secondly, based on the minimum cumulative resistance (MCR) model, 34 potential ecological corridors and 41 ecological strategic nodes are identified. Finally, ideas for how to the prioritize ecological security pattern construction in Nanchong City are put forward to provide a reference for the construction of ecological security patterns in hilly cities.