Landscape ecological risk assessment in the Dongjiangyuan region, China, from 1985 to 2020 using geospatial techniques

Anthropogenic activities can greatly affect the ecological environment. As an ecological protection area, it is necessary to scientifically evaluate the landscape ecological risk (LER) in the Dongjiangyuan region to provide scientific guidance for regional sustainable development. In this study, the LER was calculated, and the spatial and temporal characteristics of the LER from 1985 to 2020 were analysed using geospatial techniques. The results show that the proportion of low-risk and extremely low-risk areas increased from 87.65% to 94.26% during the 1985-2020 period. The extremely high-risk and high-risk areas had a decreasing trend, and the extremely high-risk areas were concentrated in areas with impervious surfaces and croplands. The rate of risk was negative, especially in south-eastern Xunwu County, southern Dingnan County and central Anyuan County, indicating that the ecological risk has been greatly improved. The LER centre gradually migrated to the geometric centre of the study area. However, the gravity centre of extremely high risk and high risk remained in Xunwu County. The spatial agglomeration of LER changed significantly, and the overall difference between cold areas and hot areas decreased. The hot spot areas in the Dongjiangyuan region are key areas for ecological governance in the future.