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121.
Marek Makowski Lszl Somlydy David Watkins 《Journal of the American Water Resources Association》1996,32(5):937-951
ABSTRACT: This paper presents the implementation of one element of a decision support system (DSS) for regional water quality management, applied to the Nitra River Basin in Slovakia. A model-based, aspiration-led methodology for multicriteria decision support has been used for the study. Several reusable, modular software tools have been developed and implemented: a problem-specific generator to produce the core part of the mathematical programming model, tools for the generation and interactive modification of multicriteria problems, and a solver for the resulting mixed-integer optimization problem. Provided in the paper are the following: a complete formulation of the mathematical model (including the imbedded water quality model), a summary of the aspiration-reservation-led multiple criteria optimization approach applied to decision support, and an overview of results that illustrate the applied approach and provide some interesting insights to the case study. 相似文献
122.
Løkke S 《Environmental science and pollution research international》2006,13(5):342-349
Background, Aim and Scope
The paper investigates the development of the institutional basis of the present modes of chemicals regulation and management, with special attention to interrelations with the precautionary principle. Main Features: The paper elucidates on how the precautionary principle has been shaped in relation to chemicals regulation and management since Carson's Silent Spring (years before the principle was confirmed as a policy-principle in German and European legislation. Furthermore, it is examined how the precautionary principle interacted with the development of the present chemicals regulatory regime, in a complex interplay within the OECD and Member Countries. The present modes of precaution in the new EU chemical legislation – REACH – are investigated with respect to the precautionary principle, and tested against two contemporary problems; brominated flame retardants and endocrine disrupting substances. Results: The analysis demonstrates the changing character of the integration of the precautionary principle. The main tendencies are from implicit to more explicit precaution and from a closed expert-orientation towards a more deliberative approach to scientific knowledge and uncertainty. The results demonstrate that the precautionary principle is manifest in both the design of the testing strategy and in policy provisions. In particular, the substitution of hazardous substances with less hazardous is important. Discussion: Despite explicit attention to the precautionary principle, is the present reformulation of the European Chemicals policy in danger of falling into loop-holes that equal problems related to the present regulation of existing chemicals? 'Precaution' has been reduced virtually to an abstract concept that is more or less devoid of practical meaning in the regulatory process. Conclusions: It is concluded that the role of the precautionary principle in chemicals regulation will require continued scrutiny in the future shaping of the REACH strategy. Perspectives: Continued development of robust and precaution-based chemicals regulation will have to involve both new data-generation strategies and new forms of political decision-making, with special attention given to transparency and deliberative policymaking. 相似文献123.
We investigate the stock market response to firm disclosure of positive environmental information and the link from that information to environmental outcomes. We classify environmental media releases by informational content and value relevance, and assess the abnormal stock returns of each type of event. While announcements of future environmental activities lead to the largest favorable stock market reactions, there is no guaranteed link from this type of information to environmental outcomes. Further analysis of the abnormal returns shows that the magnitude of the stock market reaction depends on firm financial characteristics across all event types rather than on firm environmental performance. Our results indicate that the ability for voluntary environmental information disclosure to induce environmental self-regulation is limited to the extent that firms are able to follow through with their announcements of planned environmental activities. 相似文献
124.
Over the last three decades, ambient concentrations of sulfur dioxide (SO2) air pollution have declined by approximately 80%. This paper tests whether the 1970 Clean Air Act and its subsequent amendments caused this decline. The centerpiece of this legislation is the annual assignment of all counties to SO2 nonattainment or attainment categories. Polluters face stricter regulations in nonattainment counties. There are two primary findings. First, regulators pay little attention to the statutory selection rule in their assignment of the SO2 nonattainment designations. Second, SO2 nonattainment status is associated with modest reductions in SO2 air pollution, but a null hypothesis of zero effect generally cannot be rejected. This finding holds whether the estimated effect is obtained with linear adjustment or propensity score matching. Overall, the evidence suggests that the nonattainment designation played a minor role in the dramatic reduction of SO2 concentrations over the last 30 years. 相似文献
125.
生态县建设是实施可持续性战略的重要内容,在目前基础设施落后,资金短缺,技术力量不足的情况下,建设颇具复杂性、艰巨性,先进性和综合性的生态工程,是每个县政府的历史责任,生态建设理论的核心是社会-经济-自然复合生态系统理论、系统生态学理论,持续发展和同步建设理论三个方面的基本构架、近年来我国在农业生态工程、工业生态工程、水陆生态工程、生态县建设方面,取得了一定的经验。 相似文献
126.
论流域水质与水量集成规划 总被引:2,自引:0,他引:2
“水量”与“水质”是流域大系统的两个特征,水环境研究偏重于水质,而水资源研究则更偏重水量,但是“质”与“量”是不能截然分开的,它们之间既相互关联,又互影响,相互制约,构成矛盾的统一体,基于这一出发点,本文从规划方法学的历史发展与流域水环境大系统的结构分析入手,系统阐述了提出流域水质与水量集成规划基本概念,目标及其策略与技术路线。 相似文献
127.
Summary The distinguishing characteristics of secondary metabolism and its associated metabolites are outlined. Current theories relating to the function of secondary metabolism in plants and micro-organisms are enumerated and the view that consideration of the processes rather than the products may best explain the origins of secondary metabolism is discussed. 相似文献
128.
耕地保护中的政府责任 总被引:4,自引:0,他引:4
认为各级政府是耕地保护的主体,负有建设、管理和保护耕地的责任。十几年来,由于政府耕地保护责任的缺失,全国出现了相关法律法规缺乏协调、政策不连贯、执法力度不够、违法用地现象普遍等问题。今后应进一步落实政府责任制,为耕地保护创造良好的工作机制和条件,管理部门要提高耕地管理水平,公开政务信息,疏通司法审判渠道,切实保障农民的合法权益。 相似文献
129.
徐州市景观生态调控途径 总被引:1,自引:0,他引:1
从全新的角度提出了城市景观生态调控的概念。在分析了徐州市景观现状和问题的基础上,根据调控理念和调控目标,从空间、技术、政策3个方面提出了4个调控途径10个调控措施,从而可以在一定程度上缓解徐州可持续发展中的景观生态瓶颈问题,并为其它城市解决景观问题提供借鉴。 相似文献
130.
顾志龙 《中国安全科学学报》1998,8(1):73-77
论述了将小型链条炉排工业锅炉的炉拱设计成在运行中可以全量调节的结构,以适应燃用多种煤种的需要,并减少与固定拱操作有关的意外伤亡事故。这项技术有创新性,适用性和推广价值 相似文献