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861.
循环经济发展的现状及主要模式   总被引:19,自引:8,他引:11  
介绍了国内外发展循环经济的现状,提出发展循环经济的三种模式,即企业层面上的小循环模式,区域层面上的中循环模式和社会层面上的大循环模式。发展循环经济,建设循环型社会是当前经济发展与环境保护有机结合,转变经济增长方式,实现可持续发展的重要途径。  相似文献   
862.
中国环境内分泌干扰物的污染现状分析   总被引:7,自引:2,他引:5  
内分泌干扰物严重威胁着全球环境和生态健康,基于人为源内分泌干扰物的分类,分析了国内内分泌干扰物的污染现状,指出了目前研究工作的局限,提出了今后研究重点及污染控制的建议。  相似文献   
863.
生态综合指数及其在生态状况评估中的应用研究   总被引:7,自引:0,他引:7  
在综合分析国内外评估判断生态状况的理论和方法的基础上,提出适合我国国情的定量化的科学评估生态状况的方法--生态综合指数法。生态综合指数可用于对我国生态治理与生态破坏处于何种阶段进行量化的、内在的和综合的判断。结合我国生态建设的现状,从层次性、系统性、现实性、重要性4个方面综合考虑,对生态综合指数的指标进行了合理的选取,包括森林、荒漠、水土流失、生物多样性、湿地、草原、农田、城市生态状况等8项指标。生态综合指数的计算方法,分总指标公式、第一层次指标公式和第二层次指标公式3部分,从数学分析方法上属于层次分析法(AHP),各级指标层次分明,重点突出。将生态综合指数E(CI)分为3个区域:ECI<1,ECI=1(±0.05),ECI>1。经计算,我国生态综合指数为1.02,处于生态综合指数=1(±0.05)区域,据此判断,我国目前处于生态治理与生态破坏的相持阶段,国家必须继续进行大规模的生态建设,以促进生态系统向良性阶段递进。应用生态综合指数对我国生态状况进行综合判断,对于我国生态建设的理论和实践都具有重要意义。  相似文献   
864.
党的十五大把环境保护问题作为基本国策,并强调:“正确处理经济发展同人口、资源、环境的关系”。这表明生态问题已经引起高度重视,建立和发展生态工业已成为当前一项重要任务。本文在介绍生态工业定义的基础上,说明了建立和发展生态工业的必要性及其如何建立和发展生态工业。  相似文献   
865.
经济是农村生态环境保护的基石,它可以打破生态环境保护中的“囚徒困境”。当前,由于城市化进程的加快以及市场、政府力量等向社区的渗透,我国农村社区中经济正面临流失的危险,这是农村生态环境恶化的重要原因。经济流失只是一种暂时现象,它可以在现代农村社区中得以重构与再生,这种重构与再生,沿袭的是一种价值理性与工具理性相结合的路径。  相似文献   
866.
Analyzing the structure and functioning of the urban system revealed ways to optimize its structure by adjusting the relationships among compartments, thereby demonstrating how ecological network analysis can be used in urban system research. Based on the account of the extended exergy utilization in the sector of urban socio-economic system, which is considered as the composition of extraction (Ex), conversion (Co), agriculture (Ag), industry (In), transportation (Tr), tertiary (Te) and households (Do) sectors, an urban ecological network model is constructed to gain insights into the economic processes oriented to sustainable urban development. Taking Beijing city as the case, the network accounting and related ecological evaluation of a practical urban economy are carried out in this study in the light of flux, efficiency, utility and structure analysis. The results showed that a large quantity of energy and resources have to be consumed to maintain the structure and function of a city. The thermodynamic efficiencies of individual sector in Beijing remain at a low level. The social system in Beijing is a highly competitive network, and there are 8 competitive relations and only two mutualistic ones. The Domestic and Agricultural sector are the major controlling factors of the system. Moreover, the assessment results of Beijing are compared with the other three socio-economic systems, Norway, UK and Italy, and the ecological network function and structure comparisons are correspondingly illuminated and discussed. The conclusions indicate that the exergy-based network analysis can be refined to become an integrative tool for evaluation, policy-making and regulation for urban socio-economic system management concerning structure and efficiency at urban levels.  相似文献   
867.
For a community to manage hazards successfully, those who are responsible for planning and implementing responses to a disaster threat situation must understand the social and economic realities of populations at risk. A random sample survey of residents in the vicinity of a US Army chemical weapons storage depot in Alabama confirms that those in the lowest quartile of household income (i.e., less than US $25,000 in 1999) differ in important ways from the rest of the sample. Using economic status as a grouping variable resultedin identifying a concentration of individuals with special needs. This group differed significantly from the remainder of the sample as to demographic and attitudinal characteristics, hazard knowledge and concerns, emergency preparedness, and emergency decision-making and their likelihood of taking protective actions. Respondents in the lowest income quartile reported greater restrictions in physical abilities, fewer community contacts, a heightened concern about area hazards, and limited resources for taking preparedness and response actions.  相似文献   
868.
Modelling ecological or environmental problems has potential to provide understanding of the causes of such problems and to indicate how to better manage them. Özesmi and Özesmi (2004) showed that cognitive or causal mapping can be used to develop maps of socio-ecological systems but these maps were based on stakeholders concerned with one ecosystem. This article shows how maps from a number of different dairy farmers in different locations, but each considering his or her own farm, can be used in meta analysis to make maps that represent how farmers think their farm ecosystem works. It also shows that the combination of causal mapping with the additional technique of Q method provides a useful solution to the practical problem of selecting from a sufficiently broad range of factors with potential to use in a map. Causal mapping in single or multiple locations contributes to the goal of using peoples’ knowledge of ecosystems to improve our understanding of socio-ecological systems.  相似文献   
869.
Offshore wind power generation represents a chance to supply energy in a more sustainable way; however, the ecological risks associated with the construction and operation of offshore wind farms are still largely unknown. This paper uses the concept of ecological risk for analysing ecological changes during construction of offshore wind farms. “Ecological risk” is defined as the potentially reduced ability of providing ecosystem services. The ERSEM ecosystem model allows assessing ecological risk based on a number of selected variables (integrity indicators) and under the assumption that increased suspended matter concentration during construction of wind farms affects ecosystem functioning. We conclude that ecological risk is adequate to describe the effects of wind farm constructions, although the computation procedure still needs to be refined and the choice of indicators further optimised. In this context, the choice of indicators available in modelling as well as in monitoring time-series may offer the way forward.  相似文献   
870.
本文以个体生活资源基本需求为计算单位,探讨四川省主要生态资源能承载多少人口,预测四川省人口发展与生态资源的关系.根据本文给出的计算结果,四川省耕地费源已经饱和,其复耕事较高尚能满足人口需求;牧草场资源超载,面临荒漠化威胁;森林资源较为丰富,能够满足人口发展需求;水资源与人口关系富足有余,但工业污水排放和上游水源保护仍需给予关注.面对这一现实,四川省要进一步推行控制人口增长的生育政策;保护现有耕地资源,发展生态农业;合理规划草场资源,科学发展畜牧业;合理开发森林蕴藏资源,坚持合理采伐;加强水利设施建设,防治水污染,确保水资源可持续利用.  相似文献   
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