泥石流灾害胁迫下贺兰山东麓生态系统潜在损失风险评估OA

Assessing the potential loss risk of ecosystems under the threat of regional natural disasters is a crucial foundation for optimizing ecological security patterns and formulating risk management strategies.This study focuses on the eastern foothills of Helan Mountain as the research area.To assess debris flow disaster haz-ard,an evaluation index system is constructed based on eight factors:slope,topographic wetness index,surface cutting depth,earthquake kernel density,geological time,monthly average precipitation from April to October,distance to river,and fractional vegetation cover.A coupled model combining the Certain Factor(CF)model and the Logistic Regression(LR)model is applied to conduct the debris flow disaster hazard assessment for the study area.Meanwhile,the Ecosystem Service Value(ESV)of the study area is evaluated based on equivalent factor method,incorporating eleven service types such as food production,material production,water resource supply,gas regulation,climate regulation,environmental purification,hydrological regulation,soil conservation,maintaining nutrient cycling,biological diversity,aesthetic landscape.By spatially overlaying the debris flow di-saster hazard and ESV assessment results,the potential ecological loss risk across the study area is identified.The results indicate that there is a significant spatial variation in the potential loss risk of the ecosystem in the study area.The high-risk zones are highly coupled with the high-hazard zones,which are concentrated in the northern regions of Hebin,Shitanjing,and Baijigou Subdistrict Offices.This region accounts for 78.10%of the disaster points while covering 34.32%of the total area.There is a spatial mismatch between the distribution of ecosys-tem service value and the occurrence of disasters,exhibiting two patterns of vulnerability.The moderate-ESV zones account for 83.85%of the total area,contribute 76.07%of the total ecosystem service value,and contain 86.67%of the disaster points,facing a relatively severe threat of ecosystem service value loss.In contrast,the high-ESV zones account for only 8.83%of the total area,with fewer disaster points,yet the average potential loss reach as high as 2.51×108 yuan per disaster point,reflecting significant hidden ecological vulnerability.The re-search findings can offer scientific support for maintaining ecological security and formulating differentiated risk prevention and control strategies in the ecologically fragile areas of Northwest China.