闽三角城市群地质灾害敏感性评价

生态安全是地区社会经济可持续的根本保障,然而地质灾害会对地区的生态安全造成严重威胁,对闽三角城市群进行地质灾害敏感性分析具有重要意义。本文分别选取坡度、高程、土壤类型、NDVI、岩性、多年平均降水量、距主要公路距离和5 km格网内的地质灾害点数目这8个指标,基于SPCA、全局Moran's I和局部Moran's I,对闽三角城市群的地质灾害敏感性进行综合评价。结果表明：闽三角城市群整体处于中度敏感,不同敏感性的面积大小顺序为：中度敏感>高度敏感>轻度敏感>极敏感>不敏感,占比分别为26.96%、25.67%、23.89%、11.75%和11.72%;地质灾害敏感性由东南沿海向西北内陆呈现出由不敏感向极敏感逐渐过渡的整体趋势,并存在着明显的地带性特征;不同县（市、区）间及其内部的地质灾害敏感性均存在较大的空间异质性;地质灾害敏感性存在显著的空间自相关性,且为显著正相关,并呈现出显著的空间集聚性特征,在德化县、永春县、安溪县和南靖县为高高聚集,在惠安县、丰泽区、鲤城区、晋江市和石狮市为低低聚集;不同土地利用类型下的地质灾害敏感性综合指数大小顺序为：林地>草地>未利用地>耕地>水域>建设用地,林地和草地整体处于中度敏感,水域、耕地、建设用地和未利用地整体处于轻度敏感;多年平均降水量、坡度、距主要公路距离、地质灾害点数目、岩性和土壤类型是研究区地质灾害的主要驱动因子。

Sensitivity Assessment of Geological Hazards in Urban Agglomeration of Fujian Delta Region

Ecological safety is the fundamental guarantee for the sustainable development of regional society and economy. However, geological hazards will pose serious threats to the ecological safety of the area. It has great significance to analyze the sensitivity of geological hazards in Urban Agglomeration of Fujian Delta Region. In this paper, eight indicators are selected including slope, elevation, soil types, NDVI, lithology, average annual precipitation, the distance from the main road and the geological hazards points in 5km grids, for comprehensively assessing the sensitivity of geological hazards in urban agglomeration of Fujian Delta Region based on SPCA, global Morans'I and local Morans'I. The results show that the urban agglomeration of Fujian Delta Region is moderately sensitive in the overall, and the areas of different sensitivities decrease in the order of moderately sensitive>highly sensitive>light sensitive>extremely sensitive>insensitive, accounting for 26.96%, 25.67%, 23.89%, 11.75% and 11.72% of the regain, respectively. The sensitivity of geological hazards from southeast coast to northwest inland shows a gradual transition from insensitivity to extreme sensitivity with obvious zonal characteristics. There is significant spatial heterogeneity in sensitivity of geological hazards between different counties (cities and districts) and their internal areas. The sensitivity of geological hazards has significant spatial autocorrelation, which is a significant positive correlation, showing significant spatial clustering characteristics with the high-high clustering in Dehua, Yongchun, Anxi and Nanjing, low-low clustering in Huian, Licheng, Jinjiang, Shishi. The sensitivity synthesis index of geological hazards between different land use types is in the order of forestland > grassland > unused land > farmland > wetland > construction land. The forestland and grassland are overall moderately sensitive, while wetland, farmland, construction land and unused land are light sensitive in the overall. The average annual precipitation, slope, distance from the main road, number of 5 km grid geological hazards points, lithology and soil types are the main driving factors of geological hazards in the study area.