Lahar hazard micro-zonation and risk assessment in Yogyakarta city, Indonesia

Yogyakarta urban area (500,000 inhab.) is located in Central Java on the fluvio-volcanic plain beside Merapi volcano, one of the most active of the world. Since the last eruption of Merapi in November 1994, the Code river, which goes across this city, is particularly threatened by lahars (volcanic debris flows). Until now, no accurate hazard map exists and no risk assessment has been done. Therefore, we drew a detailed hazard map (1/2,000 scale), based on morphometric surveys of the Code channel and on four scenarios of discharge. An additional risk assessment revealed that about 13,000 people live at risk along this river, and that the approximate value of likely loss is US $ 52 millions. However, the risk level varies between the urban suburbs. This revised version was published online in July 2006 with corrections to the Cover Date.     

苍山5.2Ms级地震前后地震前兆综合危险度的变化

地震前兆综合危险度是以系统论为基础的一种综合地震预报的新方法。利用山东省每年年底的地震会商报告给出的地震前兆异常,而不是取震后的震例总结或论文给出的异常,通过“专家系统”的思想,对每一异常事件进行综合评估,计算出无量纲的、归一化的地震前兆综合危险度,分析了１９９５年９月２０日山东苍山５２Ｍｓ级地震前综合危险度的变化特征。震前综合危险度出现了一次明显的高值异常变化,震后危险度很快下降恢复到正常水平。     

QUANTIFYING AND MITIGATING FLOOD RISK IN RAPIDLY AGGRADING FLUVIAL SYSTEMS

ILOWERGUADALUPERIVER,SANJOSECALIFORNIATheLowerGuadalupeRiverProjectAreadoesnothavetheabilitytoconveytheflowofthe100-yearfloodevent.LocatedbetweentheSanrranciscoBayandDowntownSanJose,theLowerGuadalupeRiverProjectareaissubjecttomanynaturalandman-inducedagentsandnaturalphysicalprocessesthataffectthehydraulicandsedimenttransportcharacteristicsoftheRiver.Themostsignificantagentsandprocessesincludethelocalgeology,regionalseismicity,tidalprocesses,pastsubsidenceintheregion,risings…     

城市震害预测中设定地震的确定问题

提出了一个确定震害预测中设定地震的方法,包括：确定贡献量最大的潜在震源区、潜在震源区内贡献量最大的震级档和设定地震的构造位置等。以福建省泉州市为例,获得５０年超赵概率６３％、１０％和２％等３个概率水平下的设定地震。本文给出的设定地震方法纵使了确定论方法和概率论方法的优点,有助于地震危险性分析方法的发展。     

The seismic history of Catania

A detailed study of the most significant seismic effects that took place in the city of Catania has been performed in order to build up a site catalogue, to assess seismic hazard directly from it and to provide the picture of damage scenarios which happened in the past. In the last 1000 years Catania was destroyed twice (1169 and 1693) and more or less severely damaged twelve times (e.g., 1542, 1818, 1848, etc.). Destruction or severe damage are mainly related to earthquakes occurring in the coastal sector of the Hyblean foreland, while slighter, moderate effects are usually due to earthquakes taking place in the seismogenic sources of the Messina Straits and in the inner Hyblean region. The analysis of the historical reports allowed to delineate the damage scenarios of the most relevant events. In particular, for the 1693 case-history it has also been possible to map the damage distribution with reference to the existing urban settlement of the city. The site catalogue was used for assessing seismic hazard; the obtained estimates show that the probability of occurrence for intensity 7 and 10 exceeds 99.9% for 150 and 500 years, respectively. These values, associated with the high vulnerability caused by the city growth which occurred mainly before the introduction of the seismic code (1981) and without ad-hoc planning policies, implies that the urban system is exposed to high seismic risk.     

洪涝风险图的编制与应用——以太湖流域湖西区为例

洪涝风险图的编制,是洪涝平原管理中的一项重要内容,对洪涝平原生产布局和人类经济活动具有指导作用。本文介绍了一种洪涝风险图的编制方法。首先概化平原内河图,用明渠一维非恒定流模拟水流运动,得到各地的水位和流量,比较水位和数学地形模型（ＤＥＭ）的高程,将水位高过ＤＥＭ的地方划为洪涝危险区,本文以太湖流域湖西区为例作出洪涝风险图,并且介绍了洪涝风险图在国民经济部门的应用。     

中国典型水域磺胺类合成药物的环境生物地球化学特征

作为广谱抗菌的人工合成药物——磺胺类(SAs)是应用最早的一类人工合成抑菌剂之一,被广泛用于人类医疗、禽畜及水产养殖等。大量磺胺类药物的应用随代谢进入水环境中,对水生生态系统和人类健康产生重要影响并构成潜在风险,截至目前,这些影响和风险并未被探明。因此,对8种典型磺胺类合成药物在我国典型水环境中的分布特征进行了阐述,评估了它们对不同水生生物的生态毒性及生态风险,并诠释了它们在生物体内的代谢及其在生态系统中的降解途径。结果表明,不同水环境中磺胺类合成药物的浓度分布差异显著,磺胺甲恶唑和磺胺嘧啶分别在水体及沉积物中的浓度和污染程度最高;水体藻类是磺胺类合成药物最敏感的水生物种,其次是甲壳类和鱼类,磺胺甲恶唑对水生生态系统构成高风险;磺胺类合成药物进入体内后被代谢成不同的产物,与母体合成药物一同进入水环境中经历降解过程;生物降解是水生生态系统中磺胺类合成药物去除的主要途径,不同种细菌、真菌及藻类均可降解磺胺类合成药物。在以后的研究中,应当进一步加强磺胺类合成药物对水生生物的慢性毒性以及合成药物混合毒性的研究,明晰水环境磺胺类合成药物的分布-代谢-传输-效应的综合过程,探析磺胺类合成药物在水生...     

Comparison of short-term toxicity of 14 common phycotoxins (alone and in combination) to the survival of brine shrimp Artemia salina

Toxic harmful algal blooms(HABs) can cause deleterious effects in marine organisms, threatening the stability of marine ecosystems. It is well known that different strains, natural populations and growth conditions of the same toxic algal species may lead to different amount of phycotoxin production and the ensuing toxicity. To fully assess the ecological risk of toxic HABs, it is of great importance to investigate the toxic effects of phycotoxins in marine organisms. In this study, the short-te...     

基于GIS/RS的洪湖东分洪区洪水风险制图

本文计算了洪湖东分洪区洪灾损失.洪水风险带以模拟的洪水淹没深度表示.这是洪水风险综合评价模型的基础.本项研究基于GIS为基础的水动力模型计算洪水淹没深度;并以GIS/RS为基础建立了单位洪水风险评价模型,计算不同洪水风险带的直接损失.研究表明,综合洪水风险评价模型在长江流域应用是可行的.     

全球变暖导致洪水风险增加——长江洪水前景分析

近期在很多地方洪水越来越频繁且破坏性更大.20世纪90年代以来全球大洪水造成社会经济财产巨大损失,30次大洪水每次总损失额均超过10×10⁸美元.1990-1998年的9a时间的大洪水爆发的次数比1950-1985年期间Ma大洪水次数还要多.近年来中国大陆也遭受了若干重大洪水灾害(包括1996和1998年两次大的财产损失).与气候变率和变化相关的洪水灾害和易爆发程度的显著增加,这是当前最紧迫的问题.随着气温升高大气中持水量也增加,因此大规模强度的降水的可能性也增大.己观测到高而集中的大降水事件而且这种趋势在未来气候变暖条件下可能增加,大降水事件的增加是洪灾增加的必然条件.当然也有一些其它的非气象因素加剧洪灾的发生,比如土地利用变化(森林砍伐、城市化)导致土壤持水能力下降,径流系数增加;此外,人类占据了洪泛区,可能导致洪水损失增大.另外物质财富在洪泛区的积聚也导致了洪灾损失增加.毫无疑问,由于人类活动和气候的共同作用,未来洪水风险在很多地方可能增加.洪水易爆发程度被认为是暴露系数和调节能力的函数,而且在许多地方所有这些变量都可能增加.而随着暴露系数比人类调节能力增加快,因此洪水易爆发程度增大.然而,要完全从径流变化中区分气候因素导致的强烈自然变率还是直接的人为环境变化是很困难的.由于使用不同的假定情景和不同的气候模型,得到的未来环境的预测结果差异也很大.IPCC第三次评估报告中广泛讨论了气候变化与洪水之间的关系.IPCC第三次评估报告警告说,在东亚季风区非常湿润的季风季节出现的可能性非常大,进而会导致相应地区洪水风险增加.本文总结了迄今为此可收集到的有关长江洪水的资料.利用一些案例来分析研究未来假定情景下气候对水文的影响,并对东亚地区的模拟结果进行了讨论.