广东省崩塌、滑坡和泥石流灾害风险评价及时空变化

崩塌、滑坡和泥石流是广东省比较常见的地质灾害，认知其风险分布的时空变化及其驱动因素，对于制定广东省防灾减灾政策具有重要意义。在现有泥石流灾害易损度评价模型基础上，通过建立农林牧副渔及其相关产业产值与土地资源价值之间的关系，获得了土地资源价值定量计算的间接方法，解决了易损性评价中土地利用资料难以获取的问题。对比分析了2000―2010年10年间广东省崩塌、滑坡和泥石流灾害风险的时空变化。2010年各区县平均风险度为0.366，以各区县面积加权平均风险度为0.363，分别比2000年升高了0.017和0.014；2010年高度风险区县43个，比2000年增加了10个；2010年高度风险区面积89 262 km2，比2000年增加了24 301 km2。2010年全省高度风险区面积主要以珠三角地区为中心连片向沿海地区扩展。经济社会发展水平的显著提高，推高了崩塌、滑坡和泥石流灾害风险，并改变了灾害风险的分布格局，成为风险时空变化的主要驱动因素。

Risk Assessment and Temporal-Spatial Changes of Collapse,Landslide and Debris Flow in Guangdong

Collapse, landslide and debris flow are common geological hazards in Guangdong, China. To understand the temporal and spatial changes of the risk of collapse, landslide and debris flow in the province and their driving factors are of great significance for the regional development and hazard prevention and reduction. As it is difficult to obtain the value of land resources directly, in this paper, based on existed evaluation model on debris flow hazard’s vulnerability, land resource value is estimated indirectly by using the regression equation between land value and the output values of farming, forestry, animal husbandry, side-line production and fishery, and related industries. Thus the problem of quantitative evaluation of vulnerability can be solved. Temporal and spatial variations of collapse, landslide and debris flow risk in Guangdong during the 10 years from 2000 to 2010 are analysed comparatively. The results show that in 2010, the average risk of collapse, landslide and debris flow in Guangdong was 0.366, and the areal weighted average risk was 0.363, increasing by 0.017 and 0.014, respectively, as compared with those in 2000. In 2010, the number of the counties with high risk was 43, increased by 10 as compared with that in 2000. In 2010, the area with high risk was 89 262 km2, which was 24 301 km2 more than that in 2000. The high risk area mainly increased in the Pearl River Delta region, and expanded to coastal area. The economic and social development of Guangdong has significantly increased, which also causes an increase of the risk of collapse, landslide and debris flow, as well as the changes of the temporal and spatial patterns of the risk. The change of the economic and social conditions is the main driving factor for the temporal and spatial variations of collapse, landslide and debris flow risk in the province.