Optimal Scale and Scenario Simulation Analysis of Landscape Ecological Risk Assessment in the Shiyang River Basin

Abstract

The evaluation of landscape ecological risk (LER) in a river basin holds significant importance for the overall ecological environmental protection of the basin and subsequent sustainable development. The Shiyang River basin, a typical arid inland river basin, was selected as the research object, and the optimal scale of LER research was explored. Multi-period land use data was used to build an LER assessment model and reveal the temporal and spatial changes of LER in the Shiyang River basin. The PLUS model was used to simulate the spatial distribution characteristics and change trends of LER under different scenarios in 2030. The results show that the LER in the Shiyang River Basin has obvious scale dependence, with optimal granularity and magnitude of 60 m and 4.5 km, respectively. LER is dominated by higher risk and high risk categories, with significant spatial differences, showing a trend of low in the southwest and high in the northeast. The LER of the Shiyang River Basin decreased from 2000 to 2020. It is expected that the LER value under different scenarios in 2030 will show a downward trend, and the LER value under the ecological conservation priority scenario will be the lowest. This study can provide a reference for LER assessment in arid inland river basins.