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51.
We consider how ecosystem services can be incorporated into water infrastructure planning by studying the projected deepening of the Lower Weser river channel in Germany. We recalculate the project's benefit–cost ratio by integrating the monetary value of changes in different ecosystem services, as follows: (1) the restoration costs of a mitigation measure for a loss in fresh water supply for agricultural production in the estuary region, (2) the costs of a loss in habitat services, transferring the willingness to pay from a contingent valuation study to the area assessed in the environmental impact assessment, and (3) the benefits of emissions savings induced by more efficient shipping, taking a marginal abatement cost approach. We find that including monetary values for ecosystem service changes leads to a substantial drop in the benefit–cost ratio. On this basis, we argue for a reform of the standard cost–benefit analysis to facilitate more complete welfare assessments.  相似文献   
52.
为进一步加强环境保护基础设施建设,促进我国环境保护事业的更大发展,各级人民政府和环保部门必须研究采用各种切实有效的措施。环保部门应当参与投资决策,确保资金投向基础设施建设;认真调查研究,选好选准基础设施项目,做好项目审批;采取各种措施和政策,加大投资力度;加强对基础设施建设的领导,加强投资监管,加快建设进度。  相似文献   
53.
城市基础设施安全系统的结构与和谐发展   总被引:3,自引:1,他引:3  
城市基础设施安全关系到人民生命财产的安全,也制约着城市经济、社会、环境的协调发展。整个安全系统由7个安全子系统组成,它们相对独立,协调运转,共同影响城市经济、社会和环境的效益。笔者运用ANP法(网络分析法)剖析了城市基础设施安全系统的结构及其内在规律;应用科学发展观,整合城市基础设施安全系统和经济系统、社会系统、环境系统之间相辅相成的发展关系,提出一体化的可持续发展模式;同时指出,可持续发展的动力、资源和条件都受到城市内外经济、社会、环境因素的制约,为满足整个安全系统和谐发展的要求,必须科学规划和管理城市基础设施,保证其安全运行。  相似文献   
54.
Using the development of the building stock and physical infrastructure as an example, this article highlights the difficulties in combining continuous economic growth in wealthy countries with the requirements of environmentally sustainable development. There are clear limits as to how far we can get by means of ‘eco-efficiency’, and the effect of a transition to less environmentally harmful types of consumption is not sufficient if the consumption volume keeps on increasing. This is particularly evident for societal processes such as the construction of buildings and the development of physical infrastructure. Increased consumption is both a result of and a precondition for economic growth. The development of the building stock and physical infrastructure in cities is a case showing that economic growth—at any rate, in the longer term—can hardly be consistent with the preservation of species, ecosystems and food-production resources. The growth in the building stock also makes it increasingly difficult to limit energy use and reduce carbon–dioxide emissions. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   
55.
公钥基础设施(PKI)应用中的信任问题与安全解决方案   总被引:3,自引:0,他引:3  
详细论述受信证书链的替换原理、方法和过程,及其引发的用户错误受信问题。通过分析得到安全证书链的长度为小于3,但由于实际应用的业务需要和安全性需要,证书链的长度通常至少为3。最后针对上述问题给出了一种安全解决方案,通过结合存储用户个人证书的USBKEY硬件设备,采用物理信任点代替逻辑信任点来防止受信证书的替换,为用户构建安全可靠的网络信任环境。  相似文献   
56.
目前我国正在广泛开展产业园区建设,产业园区化在带来利益的同时,园区建设对生态环境也产生了一定影响。从景观生态化、基础设施生态化和建构筑物生态化三个方面进行分析研究,提供了一条生态化产业园区规划设计路径。  相似文献   
57.
为研究陆地LNG卸料系统的物理设备、信息网络及人员操作的依赖关系和信息层、人员层对设备层故障传播的影响,基于面向基础设施弹性建模语言(Infrastructure Resilience-Oriented Modelling Language,IRML),从单层网络静态风险分析和多层依赖网络的动态传播2个方面,提出LNG...  相似文献   
58.
The collection, storage, and reuse of rainwater collected in rain barrels from urban rooftop areas assists municipalities in achieving stormwater management objectives and in some areas also serves as an adjunct resource for domestic water supplies. In this study, rainwater reuse and levels of select microbial indicators were monitored for six residential rain barrels located in the Shepherd Creek watershed of Cincinnati, Ohio. Water from rain barrels typically had poor microbial quality and was used for watering indoor and outdoor plants. Rain barrel water chemistry was slightly acidic, exhibited wide ranges in conductivity, turbidity, and total organic carbon (TOC) concentrations and gave no evidence of the presence of cyanobacterial microcystin toxins. Selected microbial water‐quality indicators indicated that counts of total coliform and enterococci were consistently above U.S. Environmental Protection Agency standards for secondary recreational contact water‐quality standards. Residential rain barrels can provide water appropriate for low‐contact reuses (such as plant watering), although there may be transient periods of high levels of indicator bacteria in the collected water.  相似文献   
59.
There is now an emerging sense of the scope and nature of response that can be implemented at building and neighbourhood scales to help adapt cities and urban areas to the changing climate. In comparison, the role of larger natural and semi-natural landscapes that surround and permeate cities is less well understood. Addressing this knowledge gap, this paper outlines two case studies that describe and map the flood risk management functions offered by green infrastructure landscapes situated within the Urban Mersey Basin in North West England. The case studies establish that areas potentially exposed to flooding can be located at some distance, and within different jurisdictions, from upstream areas where the flood hazard may be generated and could be moderated via functions provided by green infrastructure landscapes. This raises planning and governance challenges connected to supporting and enhancing flood risk management functions provided by green infrastructure landscapes.  相似文献   
60.
ABSTRACT: A mathematical model is developed to optimally schedule long-term stormwater infrastructure rehabilitation activities. The model is capable of considering multiple rehabilitation projects and is driven by overall cost eensiderations. Rehabilitation activities are scheduled based on perceived reliabilities and future deterioration expected within the specified planning horizon. Future growth within the stormwater drainage basin is incorporated using chance constraints that limit the likelihood that a stormwater discharge exceeds system conveyance capacity. Model structure and development are discussed, and a hypothetical example using a drainage network is presented.  相似文献   
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