Land use/cover change and ecological network in Gansu Province, China during 2000-2020 and their simulations in 2050

Land use/cover change (LUCC) constitutes the spatial and temporal patterns of ecological security, and the construction of ecological networks is an effective way to ensure ecological security. Exploring the spatial and temporal change characteristics of ecological network and analyzing the integrated relationship between LUCC and ecological security are crucial for ensuring regional ecological security. Gansu is one of the provinces with fragile ecological environment in China, and rapid changes in land use patterns in recent decades have threatened ecological security. Therefore, taking Gansu Province as the study area, this study simulated its land use pattern in 2050 using patch-generating land use simulation (PLUS) model based on the LUCC trend from 2000 to 2020 and integrated the LUCC into morphological spatial pattern analysis (MSPA) to identify ecological sources and extract the ecological corridors to construct ecological network using circuit theory. The results revealed that, according to the prediction results in 2050, the areas of cultivated land, forest land, grassland, water body, construction land, and unused land would be 63,447.52, 39,510.80, 148,115.18, 4605.21, 8368.89, and 161,752.40 km2, respectively. The number of ecological sources in Gansu Province would increase to 80, with a total area of 99,927.18 km2. The number of ecological corridors would increase to 191, with an estimated total length of 6120.66 km. Both ecological sources and ecological corridors showed a sparse distribution in the northwest and dense distribution in the southeast of the province at the spatial scale. The number of ecological pinch points would reach 312 and the total area would expect to increase to 842.84 km2, with the most pronounced increase in the Longdong region. Compared with 2020, the number and area of ecological barriers in 2050 would decrease significantly by 63 and 370.71 km2, respectively. In general, based on the prediction results, the connectivity of ecological network of Gansu Province would increase in 2050. To achieve the predicted ecological network in 2050, emphasis should be placed on the protection of cultivated land and ecological land, the establishment of ecological sources in desert areas, the reinforcement of the protection for existing ecological sources, and the construction of ecological corridors to enhance the stability of ecological network. This study provides valuable theoretical support and references for the future construction of ecological networks and regional land resource management decision-making.