Evaluating landscape ecological risk through Supply-Demand balance in ecosystem services Evidence from China

The ecosystem service (ES) supply-demand balance (SDB) is important for reducing ecological effects and improving landscape structure. Landscape ecological risk (LER) evaluations have traditionally focused on the possibility of ES supply loss instead of the supply-demand coupled connection, meaning they do not provide an entire overview of the ecological risk scenario. Utilizing Southwest China (SWC) as a case study, this research tried to address this gap by proposing a new LER evaluation approach promoting ecosystem services SDB. It then used geo-detectors, risk area assessment and geographically temporally weighted regression (GTWR) techniques to analyze the geo-temporal features of LER and its contributing variables in the Southwest China from 2001 to 2021. By comparing the findings with the conventional LER assessment method, the results reveal that (1) the revised method is more reasonable and reliable. The overall landscape ecological risk of the Southwest China during the past 20 years presented fluctuations, with a higher value in the northeast area and a lower value in the southwest. The comparatively considerable geographical heterogeneity in high-risk regions was mainly allocated to the combination of natural elements and landscape structure features in low-risk areas. In contrast, it was primarily due to human activity in high-risk regions. Additionally, it was found that the significant evolution of the elements was non-stationary in time. Shannon diversity index's (SHDI) detrimental impacts were more pronounced with time, whereas the beneficial effects of landscape fragmenting and land use intensity (LUI) became less intense. The findings can inform theoretical arguments and policy suggestions for the SWC's ecological preservation and effective urban planning initiatives.