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481.
基于2001—2020年影响华东地区的90个台风资料,利用统计学方法,分析台风年际、月际及登陆分布特征,采用信息扩散理论方法,统计风和雨2个主要致灾因子发生概率,在此基础上,开展台风致灾因子危险性评价。结果表明:影响华东地区的台风以强台风和台风为主,年均4.5个,主要集中在7—9月,8月最多,登陆台湾省频次最多,其次为福建省和浙江省;台风的最大风速在30~40 m/s的概率较大,最大降雨量在200~400 mm的概率较大;福建省、浙江省和江西省的台风致灾因子危险性较大,为台风严重影响区;山东省和安徽省的台风致灾因子危险性中等,为中度影响区;江苏省和上海市的台风致灾因子危险性较小,为轻度影响区。  相似文献   
482.
Wetlands are major sources of various ecological goods and services including storage and distribution of water in space and time which help in ensuring the availability of surface and groundwater throughout the year. However, there still remains a poor understanding of the range of values of water quality parameters that occur in wetlands either in its impacted state or under natural conditions. It was thus imperative to determine the health of Lunyangwa wetland in Mzuzu City in Malawi in order to classify and determine its state. This study used the Escom's Wetland Classification and Risk Assessment Index Field Guide to determine the overall characteristics of Lunyangwa wetland and to calculate its combined Wetland Index Score. Data on site information, field measurements (i.e. EC, pH, temperature and DO) and physical characteristics of Lunyangwa wetland were collected from March, 2013 to February, 2014. Results indicate that Lunyangwa wetland is a largely open water zone which is dominated by free-floating plants on the water surface, beneath surface and emergent in substrate. Furthermore, the wetland can be classified as of a C ecological category (score = 60–80%), which has been moderately modified with moderate risks of the losses and changes occurring in the natural habitat and biota in the wetland. It was observed that the moderate modification and risk were largely because of industrial, agricultural, urban/social catchment stressors on the wetland. This study recommends an integrated and sustainable management approach coupled with continuous monitoring and evaluation of the health of the wetland for all stakeholders in Mzuzu City. This would help to maintain the health of Lunyangwa wetland which is currently at risk of being further modified due to the identified catchment stressors.  相似文献   
483.
Catastrophic natural hazards,such as earthquake,pose serious threats to properties and human lives in urban areas.Therefore,earthquake risk assessment(ERA)is indispensable in disaster management.ERA is an integration of the extent of probability and vulnerability of assets.This study develops an integrated model by using the artificial neural network–analytic hierarchy process(ANN–AHP)model for constructing the ERA map.The aim of the study is to quantify urban population risk that may be caused by impending earthquakes.The model is applied to the city of Banda Aceh in Indonesia,a seismically active zone of Aceh province frequently affected by devastating earthquakes.ANN is used for probability mapping,whereas AHP is used to assess urban vulnerability after the hazard map is created with the aid of earthquake intensity variation thematic layering.The risk map is subsequently created by combining the probability,hazard,and vulnerability maps.Then,the risk levels of various zones are obtained.The validation process reveals that the proposed model can map the earthquake probability based on historical events with an accuracy of 84%.Furthermore,results show that the central and southeastern regions of the city have moderate to very high risk classifications,whereas the other parts of the city fall under low to very low earthquake risk classifications.The findings of this research are useful for government agencies and decision makers,particularly in estimating risk dimensions in urban areas and for the future studies to project the preparedness strategies for Banda Aceh.  相似文献   
484.
地震灾害风险评估工作的开展是践行新时期防震减灾工作的必然要求,是了解抗震薄弱环节和高风险地区的有效手段。本文针对现有地震灾害风险评估系统在市县层级应用薄弱、针对性不强、基本未考虑地质灾害的影响等问题,在分析总结最新研究成果的基础上,以宝兴县为例,设计并构建操作方便简单、针对性强的地震灾害风险评估系统。为地方政府地震灾害风险管理、防御和风险处置等提供方法和方案,切实提高地震灾害风险防御能力,有效降低地震灾害损失。  相似文献   
485.
为填补滨海旅游灾害防范的空白,文章详细介绍了国家海洋局海洋减灾中心着手开展我国典型滨海旅游区裂流危险评估、安全警示、公众科普等技术工作。归纳总结了地形动力学概化分析、精细化数值模拟、遥感影像分析、现场勘测等裂流灾害危险性评价技术方法;详细介绍了我国海南省三亚、陵水地区重点滨海旅游岸段的裂流灾害风险及安全警示现状的调查评估情况;分析探讨了近期国内频繁出现的海滩裂流溺水事故以及国内裂流灾害公众科普宣传动态;并提出了滨海旅游灾害防范下一步的专业技术工作和科学探索方面可能的发展方向。  相似文献   
486.
The aim of this paper is to propose an integrated low cost system for monitoring the performance of beach defence works during storms. For this purpose, the site of Igea Marina, Northern Adriatic Sea, Italy, which is protected by low crested detached breakwaters, is selected. The monitoring system is composed by a video installation, for the identification of the shoreline position and of the intertidal bathymetry at high space and time resolution, and a 2DH numerical model, to reconstruct the hydrodynamics induced by coastal defenses. The accuracy of the monitoring system is verified against available measurements of waves and currents performed during a field campaign with acoustic Doppler profilers. Assimilation of data on the shoreline position in 2DH model operatively working is challenging in the improvement of the production of risk maps. These show the current intensities and flooded areas during forecasted storms. First promising results suggest the possibility of setting up an early warning tool.  相似文献   
487.
This research is an effort to develop a Risk Management-based Decision Analysis (RMDA) framework based on the common fundamental elements that define the nature of resilience in Port Infrastructure Systems (PIS). While developing a systematic process for making strategic and investment decisions, RMDA guides the decision-makers to identify, analyze, and prioritize risks involved in PIS operations; to define ways for risk mitigation, plan for contingencies, and devise mechanisms for continuously monitoring and controlling risk factors and threats to the system; and to value the adopted resilience investment plans and strategies. Our suggested RMDA framework is a policy making tool that utilizes a Decision Tree Analysis (DTA) methodology for assessing the cost-effectiveness of the devised strategies.  相似文献   
488.
我国沿海地区是极端天气和气候事件易发频发区,也是重要的人口和经济聚集地。在全球气候变化背景下,风暴潮、海浪、海冰和海啸等海洋动力灾害的形成机理、发生规律、时空特征、损失程度呈现出新的特点,重特大海洋动力灾害对我国沿海地区造成的威胁不容忽视。文章阐述海洋动力灾害时空分布特征,在分析我国沿海地区应对海洋动力灾害现状基础上,提出我国沿海地区应对重特大海洋动力灾害的对策与建议:建议开展重特大海洋动力灾害防御相关立法研究,制订国家层面应对重特大海洋动力灾害专项应急预案,建立健全重特大海洋动力灾害保险风险补偿机制以及提升重特大海洋动力灾害科技支撑能力。  相似文献   
489.
The actual or potential effects on fishing health and safety of the full scope of national and international regulatory regime components governing commercial fishing are often poorly understood. Especially lacking are comprehensive reviews of all the government policies that directly and indirectly affect fishing risk within countries with significant commercial fisheries. We present the results of a comprehensive, multi-national project that compares the regulatory regimes of six countries (Canada, US, UK, Iceland, New Zealand, and South Africa) and examines the impacts (either real or perceived) of legislation and regulations on fishing occupational health and safety outcomes. A conceptual model is proposed that identifies potential sources of direct and indirect risks to fishing health and safety in order to throw light on potential pathways from regulation to fishing safety. Our results highlight differences and gaps in the regulatory frameworks of the countries studied and point to the urgent need for improved assessment and for access to accurate and standardized statistics regarding fishing-related injuries and illnesses. We conclude with several recommendations for moving forward.  相似文献   
490.
基于GIS的徐水县干旱灾害风险区划   总被引:2,自引:0,他引:2  
以河北省保定市徐水县干旱灾害为例,对其干旱灾害风险区划进行研究。利用GIS技术,建立气象数据库,集成基础地理数据、气象观测数据和人口经济等资料;选择适当指标,实现干旱灾害致灾因子危险性、孕灾环境敏感性、承灾体脆弱性和防灾减灾能力栅格化的计算。通过建立干旱灾害风险评估模型,完成干旱灾害风险区划的绘制,并分析了徐水县干旱灾害风险区划的分布特点。结果表明,徐水县干旱灾害风险分布呈地区性差异,中部地区发生干旱灾害的风险较高,西南地区风险较低。  相似文献   
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