【作者】 赵艳萍；

【导师】 马金珠；

【作者基本信息】 兰州大学 ， 水文学及水资源， 2013， 硕士

【摘要】 泥石流是一种突发性地质灾害,其发生、发展与地形地貌的形成演化过程息息相关。近年来,泥石流灾害频繁发生,对当地的生态环境及人们的生命财产造成了巨大威胁。随着地区经济的发展,人类活动日益增加,人口和经济的相对集中使得区域易损性增大,因而泥石流灾害导致的潜在风险也不断增高。目前对于泥石流研究的理论方法尚不完善,大多停留在定性分析阶段,相对较为滞后,因而对泥石流灾害的研究意义重大。本文选择泥石流灾害较重的白龙江流域,拟通过泥石流灾害野外调查及相关资料整理分析,利用统计学方法和GIS空间分析方法,对1960年以来泥石流灾害的数量、规模和损失等进行分析,以揭示其时间和空间分布特征。主要成果如下：(1)根据前人工作的经验以及相关文献资料,同时尽可能考虑本地区的适用性,选取地质条件、地形地貌、水文及人类活动条件等影响因素作了深入的分析。其中,侧重分析了当地地层岩性、地质构造、坡度、高程、植被指数、土地利用因子与泥石流灾害分布之间的关系,以及作为触发因子的降水与泥石流间的关系,并探究了每类条件下的主要因子对泥石流活动的影响。(2)采用AHP方法构建白龙江流域泥石流影响因子的层次结构模型,并对每层中的各影响因子进行两两比较,得到任意两个影响因素的相对权重值以及每个层次下的判断矩阵。通过求解判断矩阵的最大特征值及它所对应的特征向量,进一步得到该影响因子相对于它所对应的层次中所有影响因子的相对重要性。(3)泥石流灾害主要分布在泥盆纪、志留纪的千枚岩、板岩、灰岩等岩层以及15。-35。坡度之间和海拔高度在1000-1500m的范围内；同时,植被指数在0.2～0.3范围之间的泥石流分布广泛,山地旱地区域内泥石流灾害最集中。通过AHP层次分析,得到各影响因子的权重如下：地层岩性>暴雨>坡度>地质构造>植被指数>高程>降水变差系数>大雨>土地利用>月降水量>年降水量,故可知地层岩性和暴雨是泥石流灾害的主要影响因素。与实际调查情况所得到的结果较一致,则此结论可为后期泥石流灾害风险评价因子的选取提供依据。更多还原

【Abstract】 Debris flow disasters occur frequently in the study area and widely distributed, its great destructive power, with the economic development of the area, human activity is increasing; the relative concentration of population and the economy makes regional vulnerability increases, and thus lead to debris flows potential sub-first constant increase. Debris flow research is not perfect, it has remained mostly in the qualitative analysis stage; relatively lag, so the study is significant debris flow.Firstly, on the basis of the analysis of the debris flow disaster field investigations in the area and data compilation, using statistical and spatial analysis of GIS, the study area since1960, the number of debris flow, size and loss analysis, reveal the time and the spatial distribution characteristics.Secondly, according to the previous work experience and relevant literature, but also, as far as possible, to the applicability of the area, selected made-depth analysis of the geological conditions, topography, hydrology and human activities conditions and other factors, which focuses on analysis of the relationship between the factor of formation lithology, geological structure, slope, elevation, vegetation index, land-use and the distribution of debris flows, as well as the triggering factor of the relationship between rainfall and debris flow, and to explore the main factors in each type of conditions mudslides activity.Thirdly, AHP method to build the hierarchy model of debris flow impact factor in study area, and multiple comparisons in each layer of the impact factor, get any two influencing factors relative weights, and each level under the judgment matrix. The maximum eigenvalue of judgment matrix, it corresponds to the feature vector further relative to the corresponding level impact factor relative importance of the impact factor.Through this analysis, it shows that the principle character of the time and the spatial distribution of debris flow in the study area and get the spatial distribution map of debris flow disaster, and then applied the overlapping functions of the GIS software and Spatial Analyst, statistical analysis of each factor, the result of the spatial relationships of each impact factor with the existing debris flows, and reflects the influence of the different lithology, different levels of slope, elevation with the debris flow. According to this results the debris flows are mainly distributed in the phylite, slate and limestone of the Devonian, Silurian, and15°-35°slope and altitude within the range of1000-1500m; mudslides distribution in the0.2-0.3range of the vegetation index and it most concentrated in Mountain and dry land. Finally, according to the AHP method obtained the results that the formation lithology> rainstorm> slope> geological structure>NDVI> elevation> the variation coefficient of annual rainfall> heavy rain> Land Use> monthly precipitation> annual precipitation, so we can see the formation rock and heavy rainfall are the main factors of debris flows. More consistent with the results obtained by the actual investigation, this conclusion can be provide the basis for selected to the risk assessment factors in which the latter research of debris flow disaster.更多还原