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821.
试论长江中游沿岸地区区域环境特征与洪涝灾害 总被引:2,自引:1,他引:1
首先论述了长江中游沿岸地区的区域环境基本特征:①以平原为主体的层状地表结构;②亚热带季风气候;③河网密布,湖泊众多;④过渡性的土壤和植被。然后分析了该区洪涝灾害的概况,揭示了洪涝灾害的自然原因与人为影响。 相似文献
822.
Graham A. Tobin Robert Brinkmann Burrell E. Montz 《Environmental geochemistry and health》2000,22(3):219-232
The link between sediment contamination and flooding is not well established, since flooding may exacerbate problems by spreading pollutants throughout the floodplain, or alternatively may dilute contaminants in source areas. To determine the substance of such relationships, the pattern of sediment contamination was examined in a small Idaho town following flooding in 1996. Four heavy metals were tested, nickel, chromium, zinc and copper, in 97 soil samples obtained from sites across the floodplain of the St. Joe River. Flood history and land-uses at each sample site were noted. Results showed that contamination levels generally were not high, with flood areas having lower concentrations than non-flood areas. A stronger relationship could be argued for land-use, with higher concentrations of contamination associated with some industrial sites. High levels of contamination were also found in several samples taken from recreational areas. Further research looking at the potential sources of contamination in relation to characteristics of the flood hydrology would seem pertinent. 相似文献
823.
湖北省旱涝灾害的若干统计特征及对农业生产的影响 总被引:3,自引:2,他引:1
着重分析了湖北省40多年来旱涝灾害的若干统计特征及其对农业生产的影响,指出了旱涝灾害的演变趋势,以及人类活动对灾害加剧的主导作用,为防、抗旱涝灾害提供参考。 相似文献
824.
Bolanle Wahab 《Journal of Environmental Planning and Management》2018,61(3):385-405
Frequent floods have led to loss of lives and destruction of property in both coastal and landlocked cities across the globe, particularly where floodplains have been developed without recourse to space standards. This paper investigated the contributions of contravention of building codes to flooding in flood-prone areas in the Lagos metropolis. Global Positioning Systems (GPSs) were used to determine the location and elevation above sea level of 1,025 buildings situated in 211 streets that were prone to flooding. The distance of buildings from drainage channels/the lagoon was determined in ArcGIS 10.2 environment. Findings revealed that building code contravention contributed significantly to flooding (r = 0.926). About 63.5% and 63.3% of sampled buildings contravened building-plot ratio and statutory setbacks from drainage channels/the lagoon, respectively. Proactive urban planning, strict enforcement of building codes and development control regulations are required to reduce flooding and its consequences in cities of developing nations where flooding has become an annual occurrence. 相似文献
825.
Although the impacts of federalism on environmental policy-making are still contested, many policy analysts emphasise its advantages in climate policy-making. This applies to the mitigation of climate change, in particular when federal governments (as in the U.S.) are inactive. More recently, federalism is also expected to empower sub-national actors in adapting to local impacts of climate change. The present paper analyses the role federalism in Austria played in greening the decentralised building sector (relevant for mitigation) on the one hand, and in improving regional flood risk management (relevant for adaptation) on the other. In line with the so-called matching school of the environmental federalism research strand we conclude that Austrian federalism proved to be more appropriate for regional flood protection than for mitigating climate change. We highlight that it is not federalism per se but federalism embedded in various contextual factors that shape environmental policy-making. Among these factors are the spatial scale of an environmental problem, the nitty-gritty of polity systems, and national politics (such as federal positions on climate change mitigation). 相似文献
826.
基于模糊集合分析的汛期分期方法及其应用 总被引:1,自引:0,他引:1
在模糊集合分析理论及一般方法的基础上,充分考虑汛期的发展变化具有的模糊性、随机性和过程性,以及降雨径流响应过程的特征,以汛期正向累计雨量序列及反向累计雨量序列为基础,重新构造出一新的累计雨量序列,并作为汛期划分研究的基本研究对象,提出了出入汛最高标准(ASMAX)的概念以及消除出入汛标准影响的处理方法。最后对于桥水库控制区域汛期的分期规律进行了实际应用研究,研究结果表明:于桥水库控制流域汛期开始于6月11日,结束于9月18日,其中主汛期开始于7月21日,结束于8月4日。这基本符合海河流域主汛期在“七下八上”的统计规律。也表明累计雨量序列在一定程度上可以反应出汛期所具有的过程性,更适合汛期的分期分析。〖 相似文献
827.
分形维数在洪水分期的应用 总被引:2,自引:0,他引:2
分数阶积分是分形理论的一个重要分支,应用分数阶积分进行时间序列维数估计,其精度比box维数、量规法等方法高。在此方法的基础上,以金沙江上游石鼓站42年的流量数据为研究对象,对流量散点序列进行了分形分析,在初步证明洪峰散点序列是一种分形的前提下,将分数阶积分应用到洪水分期上,通过估算的维数确定洪水分期原则并定量划分了洪水的分期时间,论证了洪水分期的合理性,并将分数阶积分估算维数法与容量维数法进行比较。对比传统洪水分期方法,分形维数分期结果较为客观,受经验和人为影响较小,但是容量维数方法需要选择大量的洪峰点,分析计算的工作量很大,而分数阶积分具有运算方便、结果准确等优点,而且建立的分形函数关系方便进一步分析研究。〖 相似文献
828.
The United Kingdom has experienced several exceptional summer flash floods in recent years and there is growing concern about the frequency of such events and the preparedness of the population. This paper uses a case study of the upper Ryedale flash flood (2005) and questionnaire and interview data to assess local perceptions of upland flash flooding. Experience of a major flash flood may not be associated with increased flood risk perception. Despite local residents’ awareness of a trend towards wetter summers and more frequent heavy rainfall, the poor maintenance of rivers was more frequently thought to be a more significant factor influencing local flood risk than climate change. Such findings have important implications for the potential success of contemporary national flood policies, which have put greater emphasis on public responsibility for responding to flooding. This study recommends, therefore, the use of fresh participatory approaches to redistribute and raise awareness of locally‐held flood knowledge. 相似文献
829.
淮河流域洪涝变化的混沌特征 总被引:15,自引:2,他引:15
从功率谱结构,Lyapunov指数,吸收子维数和可预报时间等方面分析了淮河流域洪涝变化的混沌性质,研究表明淮河流域洪涝变化是一类混沌变化序列,洪涝系统是一类混沌为动力系统,系统时初值极端敏感,长期和不可预测,其可报预时间约为5-6年。 相似文献
830.
洪水风险管理研究进展与中国洪水风险管理模式初步探讨 总被引:14,自引:3,他引:14
在对国内外洪水风险管理研究领域的主要文献进行综述的基础上,针对中国目前防洪减灾的具体情况,提出了分别从家户与企业、保险公司、政府与社会三个不同层面和利益主体加强洪水管理的思路,并进一步探讨了适合中国国情的洪水风险管理模式。 相似文献