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181.
沼气工程是养猪场废弃物污染治理的主要途径,可在一定程度上缓解农村的环境压力和能源问题。金融政策对具有正外部性的沼气项目具有激励作用,并可通过市场手段提高其综合效率。文章通过对影响养猪场的融资因素进行分析并对国内外金融政策进行比较,提出了促进规模化养猪场沼气工程发展的建议。  相似文献   
182.
解决城市生态环境问题的生态基础设施途径   总被引:9,自引:1,他引:9  
对待城市生态环境问题,该研究放弃了就事论事的单一分析和工程途径,而是提出解决生态环境问题必须依靠综合、系统的途径,即:通过建立生态基础设施来整合相关的生态过程与景观结构。以山东东营市为例,论文提出从3个步骤来实现综合问题的综合解决:①通过德尔菲法实现问题的综合与多目标的确定;②通过建立生态基础设施,综合地解决以水为核心的多个生态环境问题,实现多个目标;③评价生态基础设施对解决多目标问题的作用和效益,并为修正方案提供依据。文章在区域、城市和场地3个尺度上,提出解决东营市生态环境问题的生态基础设施实施战略。  相似文献   
183.
120 years or more of unsustainable urban development has damaged the natural environment and disrupted essential ways to stabilize water body overflow and even mitigate pluvial flooding. In light of catastrophic flooding that has occurred globally, a renewed commitment to transforming built surfaces and incorporating more green infrastructures (GIs) has emerged. In fact, one could argue that an overcommitment to GI is being touted in the literature, but largely disconnected from more real-world possibilities, considering all things. In this commentary, we make the case that as cities transition from development patterns of the past and even considering climate-induced storm characteristics of the future, a hybridized solution (e.g., Green–Gray) should be considered. Smaller approaches to urban greening have been implemented in areas that need larger-scale restorations, thus proving to be insufficient. Likewise, the uncertainty surrounding rainfall and storm events has forced us to be more strategically balanced in our efforts to achieve resilience in our stormwater infrastructure. Hybridized solutions that include a diverse set of systems, anchored in local conditions, position us best for effective urban stormwater management. In the absence of such solutions, runoff volumes will continue to rise, flooding will prevail, and disenfranchised communities will remain disproportionately impacted by these impacts of urbanization.  相似文献   
184.
重要基础设施脆弱性计算理论   总被引:1,自引:1,他引:0  
为了给重要基础设施的保护提供决策理论支持,基于重要基础设施保护中出现的安全问题,在综述脆弱性概念的发展基础上,提出脆弱性的一种可操作性概念,并将重要基础设施保护中的脆弱性分为2类:一类为保护方面的脆弱性,一类为响应方面的脆弱性。在此基础上研究了综合脆弱性的数学表达式,提出了重要基础设施综合脆弱性的评价程序,该评价程序可以应用于重要基础设施的防灾减灾研究中。  相似文献   
185.
Urban stormwater runoff nearly discharges directly into bodies of water through gray infrastructure in China, such as sewers, impermeable ditches, and pump stations. As urban flooding, water shortage, and other environment problems become serious, integrated water environment management is becoming increasingly complex and challenging. At more than 200 ha, the Oriental Sun City community is a large retirement community located in the eastern side of Beijing. During the beginning of its construction, the project faced a series of serious water environment crises such as eutrophication, flood risk, water shortage, and high maintenance costs. To address these issues, an integral storrnwater management master plan was developed based on the concept of low impact development (LID). A large number of LID and green stormwater infrastructure (GSI) approaches were designed and applied in the community to replace traditional stormwater drainage systems completely. These approaches mainly included bioretention (which captured nearly 85th percentile volume of the annual runoff in the site, nearly 5.4 x 10^5 m3 annually), swales (which functioned as a substitute for traditional stormwater pipes), waterscapes, and stormwater wetlands. Finally, a stormwater system plan was proposed by integrating with the gray water system, landscape planning, an architectural master plan, and related consultations that supported the entire construction period. After more than 10 years of planning, designing, construction, and operation, Oriental Sun City has become one of the earliest modem large-scale LID communities in China. Moreover, the project not only addressed the crisis efficiently and effectively, but also yielded economic and ecological benefits.  相似文献   
186.
针对雨水的南方丘陵城市环境景观基础设施网络问题,以雨水排泄和汇集为导向,以GIS为分析工具,计算出雨水汇集点和排泄路径的适宜性分析图,结合城市内现有环境,如公园、广场、废弃地、绿地等用地选择环境景观基础设施节点,根据现有城市用地布局、水系、道路系统,具体计算出这些环境景观设施廊道,构建一个多功能景观基础设施网络体系,在一定程度上缓解环境雨水内涝问题,同时又能改善城市景观环境,促进城市环境景观基础设施与城市环境基础设施的融合.  相似文献   
187.
目前,国内外已开展了大量农业非点源污染核算研究,但大部分经验模型缺乏对非点源污染入水体过程的考虑,而机理模型则受到资料限制,大尺度应用难度较大.针对传统研究面临的未考虑入水体过程、难以精细化模拟等核心问题,本研究基于源-流-汇理念和栅格汇流算法,构建了耦合源负荷核算、入水体过程核算、植被截留核算等模块的农业非点源污染物全过程核算方法(Grid confluence based agricultural nonpoint source pollution calculation method,GC-ANPSM).案例研究表明,GC-ANPSM方法具有较好的适用性,径流模拟误差为24.3%,总氮模拟误差为9.78%.该方法可为少监测资料地区的农业非点源污染物全过程核算提供理论和技术基础,同时为制定农业环境保护政策提供决策依据.  相似文献   
188.
针对移动无线射频识别(RFID)技术应用的日益重要性及其服务的安全性现状,基于RFID和移动通信技术相关理论,从安全和隐私的角度阐述移动RFID技术及其应用服务,分析移动RFID服务所面临的主要安全问题和安全性要求;建立一种适用于超高频移动RFID系统的安全增强型服务架构,并提出一种基于原始标签身份隐藏的隐私保护方案,以期为解决移动RFID服务各种安全问题提供帮助。分析表明,采用具有透明传输方式的安全增强型服务架构,并定期修改标签ID可以有效地保护移动RFID用户的隐私。  相似文献   
189.
The irrigation sector constitutes the backbone of Uzbekistan's economy, providing social and economic stability in the region. The sector collapsed with the fall of the Soviet Union, due to worsening of infrastructure conditions causing tensions among resource users. Subsequent irrigation management reforms were implemented in a top-down manner. More than a decade after the initial reforms – which established local Water Consumers Association (WCA) and transferred operation and maintenance responsibilities for on-farm irrigation canals – the poor performance of these associations is still apparent, illustrating the heritage of the strong role of state agencies in Uzbek water management that still affects collective irrigation management today. This paper identifies the necessary and sufficient conditions for successfully managing common pool resources (CPRs) and, more specifically, irrigation canal maintenance in the rural Bukhara region of Uzbekistan. Fifteen WCAs were examined regarding conditions that may facilitate successful irrigation canal maintenance. Methods involved focus group discussions and in-depth interviews with the associations concerned. Data gathered was analyzed using fuzzy-set qualitative comparative analysis. The results indicate that two paths of local factors can lead to well-maintained irrigation canals: (1) the combination of appropriate chairmanship skills with sustainable resource appropriation or (2) the combination of appropriate chairmanship skills with the presence of effective participatory governance. The results also illustrate the role of path-dependence and traditional co-production of irrigation management in Uzbekistan.  相似文献   
190.
运用系统工程方法和大系统理论,分析区域性森林资源-环境-经济复合大系统(FREES)的结构与原理。在可持续发展的总体要求下,将森林资源、森林环境和林业经济三个子系统作为一个有机整体,构建基于ε-约束法的多目标优化模型,以及包含各子系统的目标函数模型、约束条件模型和关联模型在内的FREES大系统分解-协调优化模型。然后,将该模型用于江苏省FREES可持续发展优化问题,得出了具有实际指导意义的最优方案。  相似文献   
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