Exploring the interactions and driving factors among typical ecological risks based on ecosystem services: A case study in the Sichuan-Yunnan ecological barrier area

Human interference and climate change have led to the loss of ecosystem services in typical ecologically fragile areas, thus triggering a variety of ecological risks (ER). Assessing ER can provide decision support to managers in addressing ecological problems. However, previous studies have focused more on the improvement and practical application of assessment methods, while the interactions between different ER and their driving mechanisms remain unclear. Thus, this paper examined the Sichuan-Yunnan ecological barrier area and constructed an ER characterization method based on the relative loss of ecosystem services, analyzed the dynamic changes of single risk (i.e., soil conservation risk (SC_R), grain production risk (GP_R), carbon storage risk (CS_R), water yield risk (WY_R), habitat quality risk (HQ_R)) and comprehensive risk from 2000 to 2020, and explored the interactions between ER and their driving factors by using correlation analysis, spatial autocorrelation, self-organization method and geo-detector. The results show that (1) the SC_R and WY_R increased significantly during 2000-2020, exacerbating regional ecological degradation, while the CS_R, GP_R and HQ_R showed a decreasing trend. (2) The comprehensive risk was rising, with significant increases in the middle-high rolling hills in the southwest and the Chengdu Plain in the east, which are mainly attributed to farmland reclamation and urban expansion. (3) Competition between different land uses exacerbated the trade-offs between GP_R and CS_R, SC_R, HQ_R, while showing spatial heterogeneity under the constraints of natural factors and topography. (4) A total of four ER clusters were identified, with the SC_R-GP_R-WY_R cluster dominating, and gradually transforming into the SC_R cluster as the landscape pattern changes. (5) Compared with socio-economic and natural factors, the proportion of forest land and cropland was the dominant factor influencing most ER changes. The results can provide scientific support for ecological conservation policy formulation and ER avoidance in the Sichuan- Yunnan ecological barrier area.