Landscape ecological safety assessment and landscape pattern optimization in arid inland river basin: Take Ganzhou District as an example

Landscape ecological security assessment aims to make a comprehensive evaluation of regional landscape ecological security through the construction of regional ecological security evaluation indicator system. According to the theory of landscape ecology, spatial principal component analysis (SPCA) and GIS techniques, we obtained the distribution of landscape ecological security pattern of Ganzhou District, Gansu province, China. We obtained the ecological sources, corridors, and nodes according to the minimum cumulative resistance (MCR) model to optimize the structure and function of ecological function network. The following results were found: the comprehensive landscape ecological security situation of the research area was on the average. The spatial distribution pattern of landscape ecological security level indicated that the low level of safety were mainly distributed in the Gobi and desert areas in the north, accounting for 19.9% of the study area, while the high safety level was mainly distributed in the northwest and southeast of the Heihe River basin, accounting for 24.8% of the study area. With points, lines, and surfaces being interlaced, a regional ecological network was constructed, which was consisted of six ecological corridors, 14 ecological nodes, a large ecological source area and a plurality of small source areas, and could effectively improve landscape ecological security level of the study area.