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71.
Reconstructing tsunami run-up from the characteristics of tsunami deposits on the Thai Andaman Coast
Tsunamis can leave deposits on the land surface they inundate. The characteristics of tsunami deposits can be used to calculate tsunami run-up height and velocity. This paper presents a reconstruction of tsunami run-up from tsunami deposit characteristics in a simple mathematical model. The model is modified and applied to reconstruct tsunami run-ups at Ao Kheuy beach and Khuk Khak beach, Phangnga province, Thailand. The input parameters are grain-size and maximum run-up distance of the sediment. The reconstructed run-up heights are 4.16–4.91 m at Ao Kheuy beach and 5.43–9.46 m at Khuk Khak beach. The estimated run-up velocities (maximum velocity) at the still water level are 12.78–19.21 m/s. In the area located 70–140 m inland to the end of run-up inundation, estimated mean run-up velocities decrease from approximately 1.93 m/s to 0 m/s. Reasonably good agreements are found between reconstructed and observed run-up heights. The tsunami run-up height and velocity can be used for risk assessment and coastal development programs in the tsunami affected area. The results show that the area from 0 to 140 m inland was flooded by high velocity run-ups and those run-up energies were dissipated mainly in this area. The area should be designated as either an area where settlement is not permitted or an area where effective protection is provided, for example with flood barriers or forest. 相似文献
72.
73.
Southern California's marine areas are heavily contaminated with dichloro-diphenyl-trichloroethane (DDT) and polychlorinated-biphenyls (PCBs), and fish consumption advisories (FCAs) have been issued throughout the region. Between 2002 and 2003, the Montrose Angler Survey, a large-scale survey of subsistence anglers, was developed and implemented on site in Orange and Los Angeles counties. This survey was intended to assist natural resource trustees in the development of restoration programs that will address injuries to natural resources and restore lost economic services for anglers, but the data were never fully analyzed. The trustees have shown a clear preference for ecological restoration programs that may take years to improve fishing services. In contrast, this analysis, which includes a random-parameter fishing site choice model, demonstrates that simple, inexpensive programs such as better signage to warn of FCAs and transportation to clean sites have the potential to yield substantial benefits quickly. This paper also focuses on how different ethnic minority groups are affected by FCAs, and determines how best to communicate risk information and change fishing behavior through outreach programs. 相似文献
74.
In shipping, safety depends on the reliability of the technical and human components of the ship-system, although the marine environment itself may sometimes be so hostile as to give rise to accidents that are beyond technical and human control. The need for a continuous analysis of shipping accidents is dictated by the accumulated evidence for the predominance of the human factor and the ever-increasing pressure for further improvement on the safety record of shipping. In this context, the effectiveness of enforced regulations towards the promotion of safety policy in shipping is assessed and the debate and focus on this issue are maintained. 相似文献
75.
海洋动物体石油烃污染评价标准参考值的探讨 总被引:1,自引:0,他引:1
目前,国内外尚无颁布任何海洋生物石油污染评价标准,为了满足海洋生物石油污染评价的需要,本文采用综合分析与毒理学分析相结合的方法,探讨和提出了海洋动物石油污染评价标准参考值,海洋鱼类、贝类和甲壳类的石油污染评价标准参考值(干重)分别为15、70 和25 m g/kg。 相似文献
76.
[ZW(*][HT6H]〓收稿日期:;修回日期:2007 05 18.
〓作者简介:[HT6SS]张永民(1973 ),男,河南延津人,副研究员,主要从事生态系统研究.[WT6HZ]E mail: [WT6BZ]zym0810@yahoo.com.cn[ZW)]
[HT4F]
[HT5K](JZ)]
[HT5H][GK2]
摘〓要:[HT5K]简要介绍了千年生态系统评估(MA)项目情景工作组的报告《生态系统与人类福祉:情景》的核心内容。该报告主要构建和评估了全球生态系统服务在21世纪前50年可能出现的4个情景,总的来讲,生态系统服务的主要变化包括:①在实力秩序情景中,生态系统的供给服务、调节服务、文化服务和支持服务都呈现下降趋势;②在适应组合情景中,生态系统的供给服务、调节服务和文化服务呈现上升趋势,而支持服务变化不大;③在全球协同情景中,生态系统的供给服务呈现上升趋势,而调节服务、文化服务与支持服务则呈现下降趋势;④在技术家园情景中,生态系统的文化服务呈现下降趋势,供给服务和调节服务呈现上升趋势,而支持服务变化不大;⑤在4个情景中,有些供给服务与其它服务之间存在显著的此长彼消的关系;⑥在4个情景中,有些生态系统服务的变化在工业化国家和发展中国家之间存在显著的差异。 相似文献
77.
This paper considers how farmers perceive and respond to climate change policy risks, and suggests that understanding these risk responses is as important as understanding responses to biophysical climate change impacts. Based on a survey of 162 farmers in California, we test three hypotheses regarding climate policy risk: (1) that perceived climate change risks will have a direct impact on farmer's responses to climate policy risks, (2) that previous climate change experiences will influence farmer's climate change perceptions and climate policy risk responses, and (3) that past experiences with environmental policies will more strongly affect a farmer's climate change beliefs, risks, and climate policy risk responses. Using a structural equation model we find support for all three hypotheses and furthermore show that farmers’ negative past policy experiences do not make them less likely to respond to climate policy risks through participation in a government incentive program. We discuss how future research and climate policies can be structured to garner greater agricultural participation. This work highlights that understanding climate policy risk responses and other social, economic and policy perspectives is a vital component of understanding climate change beliefs, risks and behaviors and should be more thoroughly considered in future work. 相似文献
78.
最近十年来中国地理科学的进展 总被引:10,自引:0,他引:10
最近十年来中国地理科学的最重要进展有:自然地理学与人文地理学的平衡发展,人口、资源、环境的研究,遥感的应用与地理信息系统的建立,自然地理定位观测,青藏高原隆起对自然环境的影响,城市与城市规划,中国历史地理研究等。最近,并已开始研究气候变化与海平面上升对中国的影响,使我国地理科学研究紧紧跟上世界发展的步伐。 相似文献
79.
Liu Wei An Weiping Zhao XinpmgSetomological Bureau of Shanxi Province Taiyuan China 《中国地震研究》1994,(3)
In this paper,the basic conditions and characteristics of the Datong-Yanggao earthquake are described in detail.The type of the earthquake,the aftershock activity,the earthquake trend,the characteristics of damage are analyzed and discussed.This earthquake belongs to a sequence of earthquake swarm type and is of the concentratedly occurring characteristics of several main shocks in a time sequence,and the aftershock activity was normally attenuated.Because of the unreasonable design of buildings and repeated vibration by several destructive main shocks within a short period,the damage in the high intensity region was aggravated.The analysis and the prediction procedure of the 1991 Datong-Yanggao earthquake(Ms=5.8)are also briefly given. 相似文献
80.
文章给出近几年国内外研究人类活动影响全球气候变化的数值模拟的新进展。 相似文献