西安市户县教场沟泥石流发育特征及危险性分析

我国山区泥石流灾害频发,其中秦巴山区就是我国泥石流灾害的多发区之一。前后两次对秦岭北麓户县涝峪镇教场沟进行了详细的野外考察。在考察过程中,对沟道内泥石流物源的总储量及空间分布,沟道的横、纵断面参数进行了详细的调查和测量;在此数据基础上,以小流域降雨-径流计算模型对不同降雨条件下,泥石流峰值流量及单次泥石流过程总量进行了计算分析。计算结果表明,该流域在遭遇50 a及以上年数一遇的强降雨时,将形成规模可观的泥石流灾害;结合沟口的实际地形资料,通过经验模型对不同降雨条件下的泥石流堆积范围进行了分析及预测,旨在为秦巴山区泥石流防灾减灾工作提供科学参考。     

中巴公路盖孜河段降雨型泥石流的激发雨型及临界阈值研究

目前针对新疆南疆干旱少雨地区降雨型泥石流的研究较为薄弱,开展泥石流发生的激发雨型和临界阈值研究具有重要理论意义和应用价值。以中巴公路盖孜河段为研究区,分析降雨型泥石流发生的降雨过程数据,探讨泥石流的激发雨型及激发雨量特征,建立研究区降雨型泥石流发生的临界降雨阈值。研究表明:(1)研究区降雨型泥石流的激发雨型包括快速、中速和慢速3个类型,这三种降雨历时的泥石流分别约占总数的64.3%、14.3%和21.4%,说明短历时的降雨更容易激发泥石流;(2)研究区降雨历时和诱发泥石流所需的平均雨强之间呈反比例关系,但降雨历时与泥石流发生所需的累计降雨之间是正比例关系;(3)利用有限的泥石流降雨过程数据拟合出降雨阈值函数,并对研究区无降雨资料区发生泥石流所需的激发雨量指标进行了合理预测。研究成果可为中巴公路沿线泥石流预警中降雨阈值确定提供基础数据,也可为新疆干旱地区的降雨型泥石流预警预报研究提供参考依据。     

基于雨量(强)条件的泥石流预测预报研究现状、问题与建议

在对基于雨量(强)条件泥石流预测预报现状综合分析的基础上,提出了目前降雨型泥石流预测预报中存在的问题:①前期降雨对泥石流发生的贡献问题;②前期降雨对泥石流影响的衰减问题;③前期有效降雨天数的确定问题;④前期降雨和短历时降雨的权重衡量问题;⑤基于前期有效雨量的泥石流预测预报模式的确定问题。提出了降雨型泥石流预测预报程式框架和相关建议:①基于雨量(强)条件的泥石流预测预报应同机理研究密切结合;②单沟泥石流临界雨量条件和预测预报应同泥石流类型密切结合;③区域泥石流临界雨量条件和预测预报应同环境地质背景密切结合。     

下游集中补给型泥石流动力学特征与防治对策——以四川省泸定县干沟泥石流为例

干沟泥石流是一条典型的下游集中补给型泥石流沟,其物源的启动、流通与堆积在700 m范围内完成.以2005年干沟泥石流过程为例,应用三种计算公式对该沟泥石流的动力学参数进行了计算.通过计算发现,三种公式计算结果差别不大,并取其平均值作为计算结果.根据干沟泥石流流量计算和形态调查对比分析,认为2005年干沟泥石流的形成过程具有明显的堵溃效应,且前期降雨对泥石流的发生影响较为明显.在对干沟泥石流动力学参数计算、物源补给特征及形成过程分析的基础上,认为干沟在2005年后易形成高频泥石流,对该沟泥石流开展监测预警尤为必要,提出了该沟泥石流监测预警方式并予以实施,可为干沟泥石流的防灾减灾提供科学依据.     

震后泥石流防治工程减灾效益评价研究

汶川地震后物源增多、泥石流规模增大,而震后泥石流防治工程设计尚缺乏理论指导,导致众多泥石流防治工程在建成后短期内就被淤满或冲毁,防治效果不理想。为探讨震后泥石流工程防治效果和工程改良,以北川县青林沟泥石流防治工程为例,采用数值模拟软件Massflow对不同降雨条件和不同防治工程条件下泥石流进行模拟,结合危险度模型,开展泥石流防治工程减灾效益评价。研究表明:1#坝(主要工程)拦截作用弱,减灾效益不明显,2#坝在防灾减灾中起主导作用;2013年青林沟内按20年一遇设计标准建成的防治工程仅能拦截一次10年一遇泥石流;对比8种工程改良和组合条件的减灾效益,最优模式为加高2#坝1m并沿用现有导流堤的"拦排"治理模式;震后进行泥石流防治工程设计时要适当考虑增大堵塞系数,提升设计年限标准,结合不同工程的作用,合理布置工程。     

东南沿海山区小流域突发地质灾害动态风险评价与应急预警

降雨作用下山区小流域突发地质灾害动态风险评价与应急预警是值得探讨的研究课题。选择浙中丘陵山区衢江区铜山源典型小流域为研究区,基于风险评价理论和模糊数学方法,构建降雨作用下山区小流域突发地质灾害动态风险预警模型,以典型代表性降雨事件为实例,以动态风险水平为预警判据,开展研究区地质灾害动态风险评价,指导区域地质灾害应急防灾。实例验证表明:在"2011·6·19"代表性降雨事件下,研究区地质灾害动态风险水平划分为极低、低和中3级区,对应于应急预警Ⅴ级、Ⅳ级和Ⅲ级区,以此有效指导分区地质灾害应急处置和防灾;而且经实际地质灾害发生情况检验与验证,本次新发生点位于地质灾害动态风险中级(应急预警Ⅲ级)区,可见动态风险水平分区评价是合理可靠的;通过降雨作用下山区小流域突发地质灾害动态风险评价可以有效指导区内地质灾害应急预警和防灾处置,具有积极的指导和实践意义。     

基于信息流理论的降雨指标与滑坡泥石流因果分析

降雨是滑坡泥石流灾害形成与发生的主导因素,但对其间的因果关系却缺乏定量的分析与验证。本文基于重庆地区2004～2016年的滑坡泥石流灾害数据与降水资料,具体分析了灾害与降雨的相关关系;并利用Liang-Kleeman信息流方法分别计算相应降雨指标与滑坡泥石流的信息流,结果表明:重庆滑坡泥石流灾害发生频次与年均降雨量的相关系数分别为0. 51、0. 53,均达到α=0. 1水平的显著性相关;年均降雨量、Pa指数、降雨日数、暴雨频次、暴雨量到滑坡泥石流均存在单向因果关系;暴雨量到滑坡泥石流的信息流最大,是诱发滑坡泥石流的最主要的因素。基于信息流理论的降水与滑坡泥石流灾害的因果分析,不仅为滑坡泥石流灾害降水预报模式提供理论支撑,也对提高滑坡泥石流灾害预报预警准确率以及开展防灾减灾工作具有重要意义。     

四川色达县切都柯沟"7·8"泥石流灾害风险评价

2004年7月8日,四川甘孜州色达县歌乐沱乡切都柯沟暴发泥石流.由于前期断断续续一个多月的降雨,使得切都柯沟多处发生崩塌,大量松散固体物质含水量趋于饱和,致使在7月8日一场不大降雨的情况下触发了泥石流.这次泥石流灾害造成的损失虽不十分严重,但泥石流过程比较典型.我们将考察结果整理成文,并用已有的泥石流风险评价模型对其危险度、易损度和风险度作了分类评价,以期为今后的深入研究和防灾减灾实践提供基础.     

基于NAM模型的长白山北景区泥石流降雨阈值研究

泥石流严重影响山区生活和建筑环境安全，建立泥石流降雨I-D阈值可以有效降低泥石流灾害的影响。但是现有的建立曲线的统计方法高度依赖于大量的泥石流和降雨事件，对于缺乏观测数据的山区来说是非常困难的，且以统计方法建立起来的阈值曲线精度有限。该文采用由NAM模型和物理模型耦合的阈值模型，其中NAM模型是集总式概念性水文模型，模拟的是流域范围内发生的降雨径流过程，可以模拟出降雨所引发的径流值。该模型在长白山北景区得到验证，长白山北景区是一个典型的泥石流沟谷，历史上记载了数次泥石流事件。利用历史引发泥石流的降雨观测数据，对提出的阈值模型进行了验证，该新模型的精度被确定为85.72%,证明该模型在泥石流预测预警方面具有很大的应用潜力。     

RS和GIS在滑坡泥石流防灾减灾中的应用

本文论述了遥感和地理信息系统在滑坡敏感性分析、可能性分析、风险分析以及在泥石流信息系统、泥石流危险度分析和泥石流预警等方面的应用,并展望了3S技术支持下的滑坡泥石流的预测、干涉测量合成孔径雷达在滑坡监测中的应用和防灾减灾决策支持系统等三个方面的前景.     

突出重点 全面防御 健全体系 强化管理 社会参与 共同抵御

陈建民局长在2011年全国地震局长会暨党风廉政建设工作会议上指出,科学规划＂十二五＂时期的事业发展,按照＂科学防灾、积极避灾＂的要求,大力开展基础探测工作,加强抗震设防要求与行业抗震设计规范的衔接,强化监管,把防震保安工作纳入新农村建设,全面提升民居的抗震能力,实现有效减灾。     

岩土矿物与疾病

地方病是与地质环境有一定依存性的疾病。它的致病物质除直接来自人类生产和生活制品外,主要源于自然界的大气、水土、岩石中。换言之,人类生存发育与一定地区的水、土和生物化学元素含量有关,当某些元素含量过高,与人需要量不相适应时,就可能导致人发生某种疾病。归纳与地质因素有关的地方病有甲状腺肿(克汀病)、克山病、硒中毒、氟中毒、铜毒、铅毒症、不孕症、食道癌、肝癌、布鲁氏菌病、鼻咽癌、口腔癌、乳腺癌等。     

陕西汉中“98.7”洪涝灾害剖析

对汉中市１９９８年７月上旬的雨情、灾情作了初步统计,分析了致灾原因及经验与教训。     

Foundations of community disaster resilience: well-being,identity, services,and capitals

If community disaster resilience is to mature into a robust and lasting area of research, methodologically facilitated dialogue between empirical observations and theory is necessary. However, methodological and empirical research has outpaced community disaster resilience theory. To address this gap, a theoretical framework called WISC is presented. WISC is named after four constructs of the framework: well-being, identity, services, and capitals. WISC relates the two concepts of community and infrastructure, broadly defined, to the four constructs it is named after. The 4 constructs are respectively defined by 29 variables. The broadest interpretation of WISC is that infrastructure supports and facilitates components of community within human settlements. Infrastructure is represented as combinations of capitals and services; community is represented by connections of identity and well-being. Ultimately, well-being of a community is dependent on that community's collective capital. But these two constructs are mediated by the intervening constructs of identity and services. WISC goes beyond existing frameworks by addressing essential elements of theory building that have been overlooked in the literature, while synthesizing other frameworks and areas of knowledge. WISC provides a powerful foundation for posing and evaluating hypotheses, improving data collection efforts, and, most importantly, enabling critical theory building.     

Social entrepreneurship,co-production,and post-disaster recovery

Post-disaster recovery requires co-production; that is, the inputs of citizens are essential for successful community recovery to occur. Citizens contribute to post-disaster recovery by volunteering, taking on consultative and decision-making roles within their communities, and directly participating in post-disaster reconstruction efforts. Without meaning ful contributions from citizens—the intended beneficiaries—unilateral efforts by public officials and authorities will inevitably fail. This study shows that social entrepreneurs can thus play a critical role in spurring post-disaster recovery by facilitating co-production. It focuses on the role of social entrepreneurs after disasters and centres on one rural village, Giranchaur Namuna Basti in the Sindhupalchowk District of Nepal. Specifically, the study uses the case of the Dhurmus Suntali Foundation's Namuna village project in Giranchaur following the 7.8-magnitude earthquake that struck on 25 April 2015 to examine the pivotal role that social entrepreneurs assume in promoting voluntary activities, community engagement, and participation in post-disaster recovery efforts.     

Ethnicity,income, and disaster preparedness in Deep South Texas,United States

This paper examines the influence of a series of demographic and socioeconomic factors on preparedness outcomes for a sample of residents of the Rio Grande Valley in the southernmost part of Texas, United States. Data were collected as part of the regional Pulse of the Valley Study, a general social survey of south Texas residents conducted by the Center for Survey Research at the University of Texas‐Rio Grande Valley. The purpose of this investigation is to understand better the effects of ethnicity and income on preparedness within a region of the US that suffers from widespread poverty and limited infrastructure and is prone to flooding and hurricanes. Taken together, the results suggest that while age, disaster experience, and income are associated with preparedness, the relationship between preparedness and ethnicity remains complex. Furthermore, policymakers should consider initiatives that address the socioeconomic and other issues that shape preparedness for a disaster.     

Immediate behavioural responses to earthquakes in Christchurch,New Zealand,and Hitachi,Japan

This study examines people's immediate responses to earthquakes in Christchurch, New Zealand, and Hitachi, Japan. Data collected from 257 respondents in Christchurch and 332 respondents in Hitachi revealed notable similarities between the two cities in people's emotional reactions, risk perceptions, and immediate protective actions during the events. Respondents' physical, household, and social contexts were quite similar, but Hitachi residents reported somewhat higher levels of emotional reaction and risk perception than did Christchurch residents. Contrary to the recommendations of emergency officials, the most frequent response of residents in both cities was to freeze. Christchurch residents were more likely than Hitachi residents to drop to the ground and take cover, whereas Hitachi residents were more likely than Christchurch residents to evacuate immediately the building in which they were situated. There were relatively small correlations between immediate behavioural responses and demographic characteristics, earthquake experience, and physical, social, or household context.