Ecological risk assessment of an ecological migrant resettlement region based on landscape structure: A case study of Hongsibu in Ningxia

In this study, the Hongsibu district of the Ningxia autonomous region is used as an example, and remote sensing images from 1995, 2000, 2005, 2010 and 2015 were selected as data sources. Landscape pattern index, ecological risk index, spatial analysis, and geographic detector were used to study the temporal and spatial characteristics of the ecological migration resettlement area. The results showed that the landscape pattern of the study area changed greatly from 1995 to 2015, the area of grassland decreased by 2.97 × 10~4 hm~2, and the cultivated land, forest land, and construction land increased by 1.90× 10~4 hm~2, 0.42×10~4 hm~2, and 0.43×10~4 hm~2, respectively. During the study period, the overall patch number of the landscape increased, and the overall fragmentation of the landscape increased accordingly. The ecological risk of the study area was dominated by low and medium risk. Among these, the ecological risk of the construction land, the sandy land, and the unused land were high; the average ecological risk decreased from 0.166 to 0.154, and the ecological risk value of the study area decreased. The geographical detectors showed that the landscape patch number, landscape fragmentation degree, landscape dominance degree, landscape loss degree, and patch density were the main influencing factors of ecological risk in the resettlement area.