基于GIS的福州市滑坡灾害综合风险评估

Integrated Risk Assessment of Landslide Hazard in Fuzhou Municipality based on the GIS Technique

滑坡灾害是福州市最为严重的地质灾害之一,并时有发生,具有极强的破坏性和突发性的特点。本文立足于福州市现存的滑坡点,利用GIS分析方法,综合考虑孕灾坏境、致灾因子以及承灾体来进行滑坡灾害的综合风险评估。研究结果表明:福州市滑坡灾害的综合风险整体偏低,主要集中于中等风险、中低风险和低风险,其对应的面积占比分别达到了34.83%、36.16%和18.39%;各县域之间的滑坡灾害综合风险存在较大的空间异质性,滑坡灾害综合风险高的地区主要是鼓楼区、仓山区、台江区和晋安区等市中心地带,而滑坡灾害综合风险较低的地区主要集中于闽侯县、连江县、马尾区、永泰县和闽清县等郊区地带,这主要是由于滑坡灾害综合风险是由滑坡灾害的危险性和承灾体脆弱性共同叠加得到的,其空间分布特征的内在驱动可能是市中心的人口密集、经济发展水平较高,导致了该地区的人口脆弱性较强、危险性较高,进而引发地区的滑坡灾害综合风险也较高,而郊区的城市引力作用较弱,导致了其综合风险也较低。

Frequently occurred, landslide hazard is one of the most serious geological disasters in Fuzhou Municipali- ty, with the characteristics of strong destructiveness and sudden. Based on the existing landslide sites in Fuzhou, with the GIS analysis method, it was conducted the comprehensive risk assessment by considering comprehensively disaster environment, disaster causing factors and hazard bearing body. The results show that the comprehensive risk of land- slide disasters is overall low in Fuzhou Municipality, which is mainly concentrated in the levels of medium risk, medi- um and low risk and low risk, with the corresponding area accounting for 34.83% , 36.16% and 18.39% , respective- ly. There is significant spatial heterogeneity in comprehensive risk of landslide disaster among the counties, the higher comprehensive risk of landslide disaster mainly concentrates in the downtown area such as Gulou, Cangshan, Taijiang and Jinan Districts, and the lower risk of landslide disaster mainly concentrates in the suburbs such as Minhou, Lian- jiang, Mawei, Yongtai and Minqing Districts. This is mainly due to the common combination of landslide hazard and vulnerability of hazard bearing body. The internal driving of the characteristics of spatial distribution may be the higher population density in the center area and higher level of economic development, which has led to the vulnerability and landslide hazard, and then to the higher higher population comprehensive risk of landslide disaster in the region. While the urban gravity effect is lower in the suburb areas, leading to the lower comprehensive risk.