面向国土空间规划的地质灾害易发性评价模型——以自然遗产地梵净山为例

Geological disaster susceptibility evaluation model in territorial spatial planning:a case study of Fanjing Mountain World Heritage Site

结合降水、地形、植被、土壤、水文和土地利用等数据构建最大熵模型和地理探测器模型相融合的乡镇单元尺度地质灾害易发性评价模型,以世界自然遗产地梵净山为案例进行模型应用.结果表明,梵净山地质灾害发生的高风险区和较高风险区主要位于梵净山东北侧的寨英镇、怒溪镇以及梵净山西侧的罗场镇、缠溪镇,中部的自然保护地灾害发生概率较低;梵净山地质灾害的发生与人类活动关系更大,最重要的影响因子为距居民点的距离;降雨是梵净山地质灾害发生的催化变量,能够强化多个影响因子的作用.采用受试者操作特征曲线以及Kvamme增益统计对模型精度进行验证,训练集和测试集的曲线下面积值分别为0.890和0.885,Kvamme增益统计值为0.89,表明所构建的模型精度较高,划分的地质灾害易发性等级区分度明显.

By means of the precipitation,topography,vegetation,soil and land use data,a township scale geological disaster susceptibility evaluation model was established based on an integration of the maximum entropy model and the geodetector model,and applied to the World Natural Heritage Site:the Fanjing Mountain.The model found that the high-risk areas and extremely high-risk areas were mainly distributed in the northeast of the Fanjing Mountain,Zhaiying town,Nuxi town,the same as the west area of Fanjing Mountain,covering Luochang town and the Chanxi town.There was a low probability of the disaster occurring in the nature-protected area in the center middle of Fanjing Mountain.The findings in there proved an apparent correlation between human activities and the occurrence of geological disasters,and the most important influencing factor was distance to settlement.The model also found that precipitation to be a catalytic factor of the geological natural disaster occurrence in Fanjing Mountain,which would strengthen the function of impact factors.The area under the curve value of the model's training set was 0.890,the model's test set was 0.885,respectively.The Kvamme gain statistic was 0.89.According to the model identification results and case application findings,the township scale geological disaster susceptibility evaluation model established could arrive at high precision and an apparent observation differentiation degree of geological disaster susceptibility.