【作者】 焦金鱼；

【导师】 杨东；

【作者基本信息】 西北师范大学 ， 自然地理学， 2009， 硕士

【摘要】 近年来,随着中国山区经济的发展,甘肃省岷县人口的迅速增长使得河谷平地及缓坡地不能满足人们对粮食的需要,导致陡坡地垦荒越来越多,造成山地植被的严重破坏,加剧了水土流失,引起了较多泥石流等地质灾害的发生,直接威胁当地人民的生命和财产的安全。因此,必须加强对贫困山区泥石流灾害机理的研究、危险性评价以及科学的防治措施。本论文征对岷县具体的自然地理环境,通过野外实地考察,结合以往泥石流灾害历史记录和已有文献资料,对全县148条泥石流沟就其发育特征和成因进行了初步的分析和研究。本文将泥石流灾害形成机理和模糊数学理论、突变理论结合起来,分别运用模糊综合判别法和突变级数评价法对研究区90条单沟泥石流和6个泥石流流域单元进行了危险性评价,评价结果与当地实际情况相符合,并提出了合理的防治措施及对策,对岷县经济建设和防灾减灾实践具有重要意义和参考价值。同时,采用突变理论与模糊数学相结合的评价方法,为解决泥石流多准则因子区域危险性评价提供了一种新思路。全文内容共分以下七部分:第一部分为引言部分。简要阐明了论文的研究背景和意义、国内外研究进展、研究的理论基础和方法,确定了本文的总体研究思路。和研究区域,提出了目前岷县泥石流的灾害现状问题。第二部分对岷县气象、水文、土壤植被、地形地貌、地质构造、新构造运动及地震、地下水类型及补、径、排特征作了简要说明。第三部分通过前面对该区泥石流灾害特征的分析研究,从泥石流形成的三个必备条件地形、松散固体物质、充足的水源入手,分析了岷县泥石流灾害的分布及其发育特征。第四部分针对岷县所处的地质环境和条件的多样性、变异性、复杂性,泥石流沟谷从形成、发展至消亡受到了很多因素的影响,从而形成了的这样一个较为复杂的泥石流灾害“模糊”巨系统,本文将模糊数学理论引入泥石流危险度的评价研究中。运用模糊综合评判法,参考国内刘希林、宫雪、陈伟等的相关文献,最后确定了沟谷纵比降、流域相对高差、泥沙沿程长度补给比、冲淤变幅、植被覆盖率等8个因素作为泥石流危险性评判因子,对岷县洮河流域90条泥石流沟做了单沟危险性评价,然后分析了泥石流形成和致灾的内在和外在原因,并对将来泥石流灾害的发展趋势做了预测分析。第五部分是在对泥石流灾害机理分析的基础上,先对突变理论的原理和特征作了总体阐述,然后将泥石流灾害形成机理和突变理论结合起来,运用突变级数模糊隶属度函数评价法对研究区6个泥石流流域单元进行了区域危险性评价,其评价结果为:属于高危险性的区域为洮河干流流域(县城——维新)段、洮河干流流域(县城——西寨)段、纳纳河流域中上游(禾驮)地区,属于中危险性的区域为十里——秦许——寺沟——麻子川南山区、蒲麻——申都——闾井东山区,属于低危险性的区域为马坞-锁龙东山区。最后总结了使用突变级数评价法进行对该区泥石流危险性区划的优点及科学性,并根据评价结果作了危险性综合区划图。第六部分综合前几部分的研究结果,突出“以人为本”的原则,系统性的提出岷县泥石流灾害的防治对策和措施、建立泥石流灾害监测网点和群测群防的预警系统,为当地政府有计划的开展泥石流灾害防治、减少灾害损失、保护人民生命财产安全提供必要的依据和参考。第七部分为全文的概括和总结。更多还原

【Abstract】 Recently, with the development of the economy of mountain area in China, the rapid increase of population in Min county Gansu province, river gulley level land cann’t satisfy people to the grain need and it results in more and more steep slope field to be reclaimed year by year. Meanwhile, the mountain vegetation deterioration , water and soil loss will lead to the more occurrence of the mud-rock flow geology disaster, threatening safety of the local people’s lives and property directly. Therefore, the mud-rock flow disaster mechanism research, hazard assessment, scientific prevention measures of the debris flows must be strengthened. This paper, according to physical geography environment of Min county, field investigation, combining with preliminary records and document data of debris flow disaster in the past, analyzed characteristics and contributing factors of 148 debris flows in Min county. Combining formation mechanism of debris flows hazard with fuzzy mathematics and catastrophe theory, this paper completed hazard assessment of 90 single debris flows and 6 valley units of debris flow in Min county Gansu Province and proposed reasonable prevention measures and countermeasures using respectively fuzzy comprehensive evaluation method and Catastrophe Progression Method. The results are found to be coincident with practical situation. It is a important significance and reference value for economic construction, defending and reducing disaster practice of Min county. Meanwhile, the method of evaluation combining catastrophe theory with fuzzy mathematics theory proved a new way in solving multiple rule-decision regional dangerons evaluation of debris flows.This thesis is devided into seven parts.The first part is the preface, briefly introduced the research background, significance, progress of debris flows’home and abroad, as well as the theoretical foundations and methods used in this study, determined the overall research idea .The second part determined the study area, illustrated briefly characteristics of meteorology, hydrology, soil vegetation, topography, geological structure, earthquake, as well as supply, runoff and drainge of the groundwater. At last, proposed the current disaster situation and facing problems of debris flows.The third part, according to the previous analysis and research to the characteristic of the debris flows disaster, three basic factors such as rich solid material resource, essential terrain and enough hydrodynamic, analyzed characterrisitics of disitribution and development of the debris flows disaster. According to the diversity, variability, complexity of the geological environment and conditions in Min County, debris flow gully formed a more complicated disaster“fuzzy”system from the formation, development to the disappearance by a lot of factors influence. The fouth part introduced fuzzy mathematics theory into the dangerons evaluation study of the debris flows. This paper which used fuzzy comprehensive evaluation method and referenced domestic relevant literature of Liu Xilin, Gongxue, Chen Wei, finally selected eight dangerons factors such as valley relative elevation,degree of vegetation cover and so on. It completed single gully risk assessment about the 90 debris flows in the Taohe valley of Min county and analyzed inherent and external causes of formation to the debris flows disaster based on natural and human ecnomical activities, assumed forecast analysis of the develeping trend of Min county debris flow disaster in future.The fifth part , based on analysing the mechanism of the mud-rock flow disaster , generally expounds the principle and characteristic of the catastrophe theory. Then, combining the mechanism of the mud-rock flow disaster with the catastrophe theory, it gave the regional dangerons evaluation of the six river basin with the Catastrophe Progression Method. The evaluation result is that: the areas belonging to high danger are the main stream river of the Taohe river basin (Town- Weixin), (Town-Xizhai), the middle and upper reaches of the Nanahe river basin (region of Hetuo) . The areas belonging to middle danger are Shili-Qinxu-Sigou-Mazichuan southern moutainous district, Puma-Shendu-lvjing eastern moutanious district. The area belonging to low danger is Mawu-Suolong eastern moutanious district. Eventally, it sumed up the merit and the scientific of the zonation of the debris-flow hazards in Min country with the Catastrophe Progression Method, and made the map of the comprehensive zonation of the debris-flow hazards according to the results of the evaluation.Part VI integrated the parts of the previous research results, highlighted the“people-oriented”principle , proposed systematicly prevention measures and countermeasures of the debris flows disaster in Min county, established monitoring networks and early warning system of mass monitoring and preventing of the debris flows disaster. Meanwhile, it provided the necessary basis and reference according to the plan for the local government to carry out the debris flow disaster prevention, to reduce disaster loss and to protect people’s lives and property.The seventh part is the paper’s summarization and main conclusions.更多还原