【作者】 赵洪涛；

【导师】 孟兴民；

【作者基本信息】 兰州大学 ， 自然地理， 2010， 博士

【摘要】 探讨滑坡、泥石流灾害多发频发区的孕灾成灾机制,研究可行的以防灾减灾为基础的可持续发展战略是减灾防灾与区域发展研究的重大课题,也是世界性的研究热点与难点。甘肃中南部地区独特的自然环境条件和人为活动的深刻影响,致使区域生态恶化,滑坡、泥石流灾害活动强烈、频繁,经济落后与贫困加剧,出现了生态、灾害与贫困之间的相互影响互为因果。本研究在分析研究区环境背景条件、陆地系统特征以及不同时间尺度滑坡、泥石流活动机制的基础上,建立区域评价指标体系,基于GIS结合MATLAB、FUZZY方法,确定基本评价栅格单元,进行区域滑坡、泥石流活动强度评价。以此为基础建立区域滑坡、泥石流灾害对区域可持续发展影响指标体系,以区县为基本单元进行滑坡、泥石流灾害对可持续发展影响评价。根据评价结果与有关因素分析,划分研究区滑坡、泥石流灾害孕灾区域类型。通过对滑坡、泥石流灾害对区域可持续发展影响程度分析,结合本区经济发展战略取向与生态建设现状,滑坡、泥石流活动灾害与可持续发展影响关系等,探讨以防治滑坡、泥石流灾害为基础的可持续发展战略实施要点与区域战略选择措施,为当地区域发展提供科学咨询和决策依据。主要研究结论如下：1.滑坡、泥石流历史过程与活动机制研究区是我国陆地系统敏感性、脆弱性最强的地区之一,也是我国滑坡、泥石流多发易发、活动强烈频繁的地区之一。陆地系统脆弱性是本区滑坡、泥石流高强度频繁活动的根本原因。本区第四纪中早期的滑坡、泥石流规模、强度远远大于今天。近50年是本区人类改造环境的高潮,也是人为作用促发滑坡、泥石流的高潮。触发响应机制是控制区域滑坡、泥石流活动规模、强度的核心机制,掌握不同滑坡、泥石流类型区触发响应阈值,有助于认识滑坡、泥石流活动时空分布规律并进行滑坡、泥石流灾害预警预报。2.区域滑坡、泥石流活动强度评价基于GIS结合MATLAB、FUZZY的评价方法,可以进行区域高分辨率评价以及区划研究。本评价结果表明,研究区存在四种滑坡、泥石流活动强度分布模式,即Ⅰ高触发、高响应、高强度区(陇南西部)；Ⅱ高触发、低响应、低强度区(陇南东部区)；Ⅲ低触发、高响应、低强度区(陇中中南部)；Ⅳ低触发、低响应、低强度区(陇中北部)。3.区域滑坡、泥石流灾害对可持续发展影响滑坡、泥石流灾害使本区人地关系矛盾激化,基本建设投资加大,对财产、资源、环境损失破坏巨大,形成与增强了“PPE怪圈”与“多米诺”现象。单纯实施防灾措施存在诸多问题困难,实施防灾可持续发展是必然选择。4.滑坡、泥石流灾害对区域可持续发展影响评价陇南西部、甘南高原东部与天水连片区域的市县滑坡、泥石流灾害危险性最强,陇南东部与陇中中南部市县属于潜在高危险性致灾区。兰州、武都、天水形成三个易灾中心,环绕武都的西和、礼县、宕昌、文县、舟曲、成县形成较强易灾区；以渭河干流为轴天水为核心向中上游分布的武山、甘谷、秦安、庄浪、陇西、漳县形成较强易灾区。减灾能力最弱的是卓尼、迭部、舟曲、积石山、东乡、和政、临夏等少数民族贫困县,以及处于偏远贫困县的宕昌、康县、文县、两当、岷县。对可持续发展强烈影响有,武都、文县、舟曲、宕昌、天水、礼县、兰州；较强影响的有,西和、武山、迭部、岷县、甘谷、漳县、秦安、康县。5.区域滑坡、泥石流孕灾类型分区研究区可分为10个孕灾类型区,即陇中黄土高原北部低危险—低易灾区,陇中黄土高原中北部较高危险—较高易灾区,陇中黄土高原中南部较高危险程度—较高、中度易灾区,陇中黄土高原西南部较高、中低危险程度—中低易灾区,陇中黄土高原东南部高、较高、中度危险程度—中高易灾区,陇南山地西部高危险—高、较高易灾区,陇南山地北部高、较高危险性—较高易灾区,陇南山地东部较高、中度危险—较高易灾区,陇中、陇南、甘南山地高原过渡区较高危险—较高、中低易灾区,甘南高原东部高原山地区较高危险—低易灾区。6.防灾可持续发展战略实施要点是,加快经济发展、改变发展方式,发展建设符合滑坡、泥石流防治原则；通过完善生态建设措施,建立滑坡、泥石流灾害防治有效模式；拓宽防灾投资渠道、遵循价值效益原则、分期治理重大滑坡、泥石流灾害；预防为主与土地利用集约化；控制人口、移民与城镇化；发展信息科技、文化教育事业与提高人口素质;强化滑坡、泥石流灾害管理措施；加强滑坡、泥石流灾害监测、预警预报与防治技术研究,提高灾害防治能力。更多还原

【Abstract】 It has become focal research topics worldwide to make researches on both the formation mechanism of disasters in landslide and debris flow prone areas, and sustainable development strategies based on prevention and mitigation of disasters. The vulnerable natural environmental conditions and human’s negative impacts in central and southern Gansu Province, China resulted in ecological degradation, active and frequent landslides and debris flow, and continuous poverty.A regional evaluation system was set up based on analysis of study region’s environmental factors, land system and landslide mechanism at deferent time scales, and raster cells as our basic study unit to evaluate the magnitude of landslide debris hazards were identified by using Geographic Information Systems (GIS), MATLAB and fuzzy methods in the paper. In addition, a system of indicators of impact of regional landslide and debris flow on regional sustainable development was developed, which can be used for impact assessment of landslides and debris flow on sustainable development based on county levels. The potential hazard areas and types can be clarified according to the assessing results and analysis of related factors. Therefore, key strategic points and regional strategic measures for sustainable development as well as scientific consulting and decision-making will be worked out in accordance with prevention and mitigation of landslides and debris flow by taking into account of economic development priorities, ecological conditions and impact of landslides and debris flow on sustainable development. Main conclusions drawn from the research are as follows:1. The formation mechanism and process of landslide and debris flowThe study region is characterized with being one of the most sensitive and fragile land systems as well as one of most frequent and prone areas of landslide and debris flow in China. The fragile land system is the root cause for high frequency and magnitude of landslides and debris flows in this region. In early Quaternary Period, the frequency and magnitude of this kind of natural hazards were even much worse than what they are today. However, the past 50 years had become a peak period when more improper intensive human activities intensified the frequency of such hazards greatly. The trigger-response mechanism is the core mechanism for controlling the spatial scale and magnitude of landslide and debris flows. Therefore, it is very important to know the trigger-response threshold in the region where hazard risk is higher in order to develop a better hazard forecasting system and to know the distribution pattern of the landslides and debris flows.2. Strength assessment of landslide and debris flowsBy using GIS, MATLAB and FUZZY method, the strength of landslides and debris flows could be evaluated based on high resolution images. Four kinds of strength scales were divided in the research area:Ⅰ. Area with high frequency, high response and high strength (western Longnan area);Ⅱ. Area with high frequency, low response and low magnitude (eastern Longnan area);Ⅲ. Area with low frequency, high response and low magnitude (central and southern region in central Longzhong);Ⅳ. Area with low frequency, low response and low magnitude (northern of central Longnan area).3. Impacts of landslides and debris flows on sustainable development in the study region In this study region, hazards of landslides and debris flows have intensified the conflicts between humanity and land system. As a result, economic development has consumed natural resources greatly and caused more serious environmental degradation. Thus, in this region, these two factors have integrated together and created both Domino Effect and PPE Circle (The vicious circle among the increase of population, poverty and environmental degradation). As a result, hazard prevention strategy in a sustainable way is much more effective than simple hazard prevention methods.4. Assessment of impacts of landslide debris flows on sustainable developmentCounties located in western Longnan, eastern Gannan Plateau and Tianshui have the highest risk of landslide and debris flows. Counties in eastern Longnan and central and southern Longzhong have the highest potential risk possibilities. Lanzhou, Wudu and Tianshui have formed three areas prone to hazards. Xihe, Lixian, Dangchang, Wenxian, Zhouqu and Chengxian that surround Wudu area have higher risk possibilities as well. Along the Wei River, six counties that are distributed around Tianshui, including Wushang, Gangu, Qin’an, Zhuanglang, Longxi and Zhangxian, are areas having higher hazard risk as well. Those areas having the lowest hazard mitigation capacities include the state-designated poverty and minority counties including Zhuoni, Diebu, Zhouqu, Jishishan, Dongxiang, Hezhen, and Linxia as well as some remote disadvantaged poverty countries such as Diexian, Kangxian, Wenxian, Liangdang, and Mingxian. Wudu, Wenxian, Zhouqu, Dangchang, Tianshui, Lixian and Lanzhou are areas where hazards have formed most strength impact on sustainable development, and Xihe, Wushan, Diebu, Mingxian, Gangu, Zhangxian, Qingan and Kangxian have potential strength impact on sustainable development.5. Regional hazard types classification The area can be divided into 10 types of hazards according 10 the hazard risk possibilities of landslides and debris flows:Lower risk--less hazard region in Northern Loess Plateau, higher risk-higher to medium hazard region in central and northern Loess Plateau, higher to lower risk--moderate hazard region in central and southern loess plateau; the high, higher to medium risk-medium to high hazard region in the southeastern parts of Longzhong Loess Plateau; High risk-high and higher hazard region in western parts of Longnan hills; high and higher risk-higher hazard region in northern parts of Longnan hills; higher to medium risk-higher hazard region in eastern parts of Longnan hills; low risk hazard region in southwestern Loess Plateau; high, higher and moderate risk--moderate to high hazard region in the western mountain region; higher risk-higher and medium hazard region in the transition zone of Longzhong, Longnan and Gannan Plateau; and higher risk-lower hazard region in the eastern parts of Ganan plateau.6.Sustainable hazard prevention strategiesKey strategies consist of following points:6.1 To speed up economy development and adjust development approaches;6.2 To develop principles of prevention of landslide and debris flows;6.3 To develop an effective model for prevention of and control for landslides and debris flow through ecological rehabilitation;6.4 To control major landslides and debris flows in phases by expanding channels for disaster funds, by abiding by the cost-benefit principle;6.5 To focus on prevention-oriented strategies and utilize land resources in a more intensification way;6.6 To control population, migration and urbanization;6.7 To increase population quality by improving information technology and education;6.8 To strengthen the hazard management measures;6.9 To strengthen research on the disaster monitoring, early-forecasting and warning technologies in order to improve hazard prevention ability.更多还原