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191.
城镇化的发展使不透水面积不断增加,往往导致地区的水文过程发生较为明显的改变。以太湖上游西苕溪流域内的安吉城镇化实验小区为例,在对研究流域50多a长系列水文气象资料和区域城镇化特征作较详细分析的基础上,结合2005~2008年短时间尺度降雨径流观测实验,通过雨量、水位以及下垫面等数据分析,选用Storm Water Management Model这一暴雨洪水管理模型对该地区的典型洪水过程进行了模拟,对其降雨径流规律进行了分析。结果表明:该模型对该区域的模拟效果较好,误差较小,可以用于该城镇化地区的降雨径流过程模拟和洪水规律定量分析;分析该实验小区降雨径流过程可知,城镇化使该地区洪水上涨过程明显加快,6场典型洪水的峰型系数均值为305,洪峰流量增大而滞时缩短,较快的汇流速度使该地区的防洪压力较大。实验观测方法及模拟分析成果将有助于对太湖地区小流域城镇洪水过程特征与规律的认识,对我国东部城镇地区的防洪、规划与管理也具有重要的借鉴意义  相似文献   
192.
徐国莉 《环境与发展》2020,(4):206-208,210
本文依据规划指导原则、适时调整原则、协调一致原则、相邻适用区达标原则和国家《城市区域环境噪声适用区划技术规范》(GB/T15190-2014)中方法和要求,在扎兰屯市城市总体规划(2012-2030)的基础上,对扎兰屯市中心城区进行声环境功能区域划分,并提出了相应的声环境管理要求和城市噪声控制措施及对策。  相似文献   
193.
China's water scarcity   总被引:1,自引:0,他引:1  
China has been facing increasingly severe water scarcity, especially in the northern part of the country. China's water scarcity is characterized by insufficient local water resources as well as reduced water quality due to increasing pollution, both of which have caused serious impacts on society and the environment. Three factors contribute to China's water scarcity: uneven spatial distribution of water resources; rapid economic development and urbanization with a large and growing population; and poor water resource management. While it is nearly impossible to adjust the first two factors, improving water resource management represents a cost-effective option that can alleviate China's vulnerability to the issue. Improving water resource management is a long-term task requiring a holistic approach with constant effort. Water right institutions, market-based approaches, and capacity building should be the government's top priority to address the water scarcity issue.  相似文献   
194.
Experimental trampling trials using a standardized methodology were undertaken in 10 replicate blocks in three vegetation types in an urban reserve in the subtropics of Australia. In each block different intensities of trampling (controls, 10, 25, 50, 100, 150, 200, 250, 300, 400 and 500 passes) were applied, and vegetation parameters were measured pre-trampling, immediately after trampling and 2 weeks later. A Fern understorey had low resistance to trampling intensity, with reductions in relative vegetation height and cover with as few as 10 passes. A Tussock grass understorey showed moderate resistance with reduction in height at 25 passes and cover at 50 passes. A Disturbed grassland dominated by lawn grasses had the highest resistance, with reductions in vegetation height at 100 passes, but cover was affected by as few as 10 passes. The resistance indices (number of passes required to reduce vegetation cover by 50%) of three vegetation types were 210, 360 and 860 passes, respectively. When these values were compared with those for 52 other vegetation types considerable variation was found within life forms, climatic zones and vegetation types indicating that the response of a specific community may not always be predictable.  相似文献   
195.
环境应急监测管理体系研究   总被引:6,自引:4,他引:2  
从环境应急监测制度建设和突发性环境事件应急预案两个方面就环境应急监测管理体系问题进行了论述。在制度建设方面主要介绍了环境应急事件应注意的几个问题及解决办法,从环境主管部门、企业、人员、装备及应对的方式方法等几个方面提出了自己的想法和观点。在突发性环境事件应急预案方面主要介绍了应包含的内容、制订要求及演练过程。  相似文献   
196.
In this article we present a framework for assessing climate change impacts on water and watershed systems to support management decision-making. The framework addresses three issues complicating assessments of climate change impacts—linkages across spatial scales, linkages across temporal scales, and linkages across scientific and management disciplines. A major theme underlying the framework is that, due to current limitations in modeling capabilities, assessing and responding to climate change should be approached from the perspective of risk assessment and management rather than as a prediction problem. The framework is based generally on ecological risk assessment and similar approaches. A second theme underlying the framework is the need for close collaboration among climate scientists, scientists interested in assessing impacts, and resource managers and decision makers. A case study illustrating an application of the framework is also presented that provides a specific, practical example of how the framework was used to assess the impacts of climate change on water quality in a mid-Atlantic, U.S., watershed.  相似文献   
197.
In The Netherlands shoreline retreat is actively counteracted, mostly by means of beach nourishment in which some allowance is made for natural fluctuations. For some parts of the coast, however, a more active socalled ‘seaward coastal defence strategy’ might be more profitable. This applies to coasts with a small dune ridge subject to severe erosion. According to this strategy the morphological system is influenced in such a way that erosion is prevented, which will result in a stable or even an accretion coastline. The effectiveness of the seaward coastal defence strategy has to be compared with maintenance by beach nourishment. The effects on the morphological system, the environment and other interests must also be analysed. Several seaward solutions are possible. In order to gain more insight into the behaviour of these solutions, comparative pilot studies have been executed for the most vulnerable locations. This paper gives an overview of the main conclusions of the pilot studies in comparison with sand nourishment, the main coastal defence measure.  相似文献   
198.
叙述了安全与经济效益及安全管理与施工进度、工期的关系,指出安全工作必须从严从细、从实管理,走现代化的管理之路。  相似文献   
199.
The assessment of human-induced pressures on the coastal area is essential to target management plans effectively, and moreover is required by the EU Water Framework Directive. A simple and cost-effective assessment of human-induced pressures on the coastal zone is applied using two methodologies: a qualitative visual assessment which uses satellite images; and a quantitative assessment based on governmental census data. These methods are applied to defined areas (23 areas) of four Italian regions: Liguria, Tuscany, Latium and Sardinia. The results show a high agreement (83%) between these two methods, in which only four of the 23 areas are classified differently. These differences may mainly be ascribed to the qualitative or quantitative properties of the methods, and to the different geographical units adopted. These characteristics however provide complementary information, which suggests that the application of both proposed methods confirms reliability and allows fine-tuning of the assessment. The pressure assessment proposed is simple, time and cost-effective, and repeatable over time and space. It therefore can be applied in different contexts to respond to legislative requirements or to target management plans and remedial actions effectively.  相似文献   
200.
天然气管道工程风险对策研究   总被引:3,自引:0,他引:3  
风险管理对策包括风险规避、风险控制与消减、风险自留和风险转移四个方面,风险管理的目标即是通过科学的风险管理策略使风险降到可以接受的水平。企业对风险的容忍程度除与风险控制的期望成本相关外,还与企业的风险偏好,以及政治、经济等外部环境因素相关。管道建设工程面临的风险因素复杂,可以从人的因素、物的因素、环境的因素和管理的因素四个方面进行识别和归类。各风险事件发生的町能性以及后果严重性各不相同,在管道建设工程风险管理中过程中要综合采用各种风险对策,使每一风险因素降低到企业所能够承受的水平,甚至可以采用改线绕过特定风险地域或保险转移的策略,使项日业主不再承担特定的风险责任。  相似文献   
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