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561.
Is a voluntary approach an effective environmental policy instrument?: A case for environmental management systems 总被引:6,自引:0,他引:6
Toshi H. Arimura Akira Hibiki Hajime Katayama 《Journal of Environmental Economics and Management》2008,55(3):281-295
Using Japanese facility-level data from an OECD survey, we estimate the effects of implementation of ISO14001 and publication of environmental reports on the facilities’ environmental performance. While most previous studies focused on an index of emissions toxicity, this study examines three areas of impacts, none of which have been explored in the literature: natural resource use, solid waste generation, and wastewater effluent. The study is also unique in that the effectiveness of ISO14001 is considered in relation to environmental regulations. Our findings are summarized as follows. First, both ISO14001 and report publication help reduce all three impacts; the former appears more effective in all areas except wastewater. Second, environmental regulations do not weaken the effect of ISO14001. Third, assistance programs offered by local governments—a voluntary approach—promote facilities’ adoption of ISO14001. These findings suggest that governments can use command-and-control and voluntary approaches concurrently. 相似文献
562.
The steady-state assumption is a mainstay for the analysis of ecological systems with more than three or four states. However, it is well accepted in ecology that inputs to large systems come in pulses assumed to have a reasonably constant magnitude and frequency. Steady pulse inputs and the use of electro-chemical–mechanical control systems methodology enables limited short term dynamic responses of ecological systems of a scale often occurring in systems of potential engineering importance to be analyzed. This paper explores and presents a survey of multi-input–multi-output (MIMO) control systems analysis of ecosystem network models to better understand pulse frequency issues and further develop experimentally verifiable approaches to testing the MIMO concept. The analysis process is demonstrated using two network model exemplars. Two aspects of MIMO analyses appear relevant to understanding ecological systems: (1) Eigenvalue invariant analyses and singular value decomposition (SVD) analyses enable assessment of stability and relative strength of states. Eigenvalues reflect time constants and provide a check on experimentally determined system matrices. (2) Analysis of SVD versus frequency for each output indicates maximum pulse frequencies that allow system components to benefit from pulsing. As a group, MIMO analyses complement other analytical methods and provide a theoretical systems focus convenient for analyzing ecosystems from an engineering perspective. 相似文献
563.
A Markov model for assessing ecological stability properties 总被引:1,自引:0,他引:1
Ecological systems are frequently modeled as dynamic systems. It is natural then to use the techniques of dynamic systems theory to analyze such models. However, the methods and results that are produced by dynamic systems theory do not always capture the aspects of ecological systems that are of greatest interest to managers and decision-makers. We identify some of the challenges of using dynamic systems theory to explore ecological systems and propose an alternative approach that emphasizes the understanding of transient effects in light of uncertainty and variability. We illustrate this method by an examination of a model for phosphorus levels in fresh water lakes. 相似文献
564.
565.
Comparative Toxicity of PCBs and PBDEs Using Human Cancer Cell Lines and Zebrafish Embryos 总被引:2,自引:1,他引:1
SHEN Hua-ping HUANG Chang-jiang LU Fang YANG Jun-hu TANGUAY Robert SUN Lu-zhe DONG Qiao-xiang 《生态毒理学报》2009,4(5):625-633
研究了6种多氯联苯(PCBs)3,3′,4,4′-四氯联苯(PCB77)、2,3,3′,4,4′-五氯联苯(PCB105)、2,3′,4,4′,5-五氯联苯(PCB118)、3,3′,4,4′,5-五氯联苯(PCB126)、2,3,3',4,4',5-六氯联苯(PCB156)和商业型混合多氯联苯Aroclor1254,两种多溴联苯醚(PBDEs)2,2′,4,4′-四溴二苯醚(PBDE47)、十溴二苯醚(PBDE209)对人类癌细胞生长和斑马鱼脱膜与不脱膜胚胎发育的影响.8种化合物均使用0.01、0.1、1.0、10μmol·L-14个浓度进行1~6d的暴露实验.结果表明,PBDE209在最高浓度10μmol·L-1下对结肠癌细胞HCT116(暴露3d后)和RKO(暴露5d后)具有显著的生长抑制作用,所有化合物均对乳腺癌细胞没有显著影响.相比之下,化合物对受精后5~6h(5~6hpf)的斑马鱼胚胎的毒性效应显得比较明显,而各化合物对胚胎的致畸和致死效应又不相同,其毒性强弱依次为PCB126≈PCB156>PCB1254(Aroclor1254)>PBDE47>PCB77>PCB105≈PCB118≈PBDE209.其中PBDE209在未脱膜暴毒后均无致畸与致死现象,脱膜暴毒后最高浓度才表现出显著意义的致畸作用,而PBDE47在最高浓度下可产生高达80%的致畸率,这说明胚胎绒毛膜具有有效阻挡大分子物质如PBDE209进入的作用.PCBs的毒性效应与其空间结构密切相关.如PCB126和PCB105具有相同的分子式,前者在1μmol·L-1下就引起了显著的致死和致畸效应,而后者即使在10μmol·L-1下也没有显著的效应.实验结果也说明不同类型的实验对象所展示的毒性效应并不相同,化合物对体外培养的细胞和发育中的胚胎具有不同的影响. 相似文献
566.
为研究四溴二苯醚(BDE-47)对原代培养人甲状腺细胞功能的影响,分别用浓度为10-12、10-10和10-8mol·L-1的BDE-47处理原代人甲状腺滤泡上皮细胞(TEC)24h,采用化学发光酶联免疫检测法检测细胞上清液中甲状腺球蛋白(Tg)的浓度,半定量逆转录聚合酶链反应技术检测功能相关的Tg基因和双链复合蛋白8(Pax-8)基因的表达.结果表明,10-12、10-10mol·L-1暴露组Tg分泌量较对照组显著减少(p<0.05),而10-8mol·L-1BDE-47组Tg分泌量与对照组无显著性差异(p>0.05).甲状腺功能相关Tg基因和Pax-8基因的表达量随BDE-47浓度的增加而显著降低(p<0.05),呈明显的剂量-效应关系.以上结果提示,BDE-47对离体培养的原代人甲状腺细胞的功能具有抑制作用,甲状腺功能相关Tg基因和Pax-8基因的表达下调可能是其作用机制之一. 相似文献
567.
In 1997 a workshop was held on the subject of how to cope with accelerating technologies. These are industries such as aviation, air traffic control and biotechnology, amongst others, where the rate of technological development is significant. A number of papers were presented from a range of viewpoints and in a variety of different industrial contexts. The papers ranged from theoretical models to help understand the process of acceleration and its impact on organisational learning, to practical analyses of future potential risks in specific accelerating industries such as air traffic control. The aim of the papers and the workshop as a whole was to provide insight into the problems associated with accelerating technologies, and thereby derive measures to control or cope with such acceleration. The problems arising from acceleration, as predicted by the theoretical models and evidenced by experiences in accelerating industries (e.g. aviation) are manifold. Two examples of particular problems are unforeseen risks in an industry (a lack of forward vision), and a failure to learn adequately (i.e. in time) from incidents occurring in an organisation (a lack of constructive hindsight). There is also an incipient danger of society being driven by technology rather than being led by social needs. Even if each technology ultimately becomes ‘ultra-safe’, it will nevertheless have its own ‘event horizon’, limiting useful further progress. Each of the papers from the workshop is summarised and integrated into a three-part synopsis of the workshop. This covers the context of accelerating technologies, modelling their impacts, and deriving coping strategies. Four of the papers are included in their entirety as separate papers in their own right in this special issue of Safety Science. 相似文献
568.
Krystyna A. Stave 《Journal of the American Water Resources Association》2001,37(5):1369-1379
ABSTRACT: This paper examines the co‐evolution of the Las Vegas, Nevada metropolitan area, Las Vegas Wash ecosystem‐a downstream riparian wetland‐and Wash management as a case of urban‐environment dynamics. Since Las Vegas Wash provides the primary drainage for Las Vegas, changes in the urban system lead to changes in the Wash and its ecosystem. The population of the drainage area has grown from approximately 1,000 people in 1900 to more than 1.3 million in 2000. This phenomenal population growth led to increased Wash flow, from less than .03 m3/sec (1 ft3/sec) to over 7.4 m3/sec (260 ft3/sec), and consequent ecological changes from a nearly dry wash to a rich wetland, and now to an eroded system. As the Wash ecosystem changed, valuation of Wash characteristics by residents and resource managers also changed, shifting the focus of management and use, which ultimately led to further ecosystem changes. Reciprocal relationships among human activity, environmental change, and management in this urban area highlight the need for a comprehensive and dynamic systems perspective and adaptive approaches in urban environmental management and make this a particularly compelling case study. This paper describes a conceptual systems framework for adaptive urban‐environment management derived from this case. 相似文献
569.
浅析企业“绿色化”支持系统可持续设计 总被引:7,自引:0,他引:7
所谓企业“绿色化”是指企业基于绿色化战略,以绿色技术采用为其内在需求,积极开展绿色营销,建立企业绿色文化,进而创建以追求经济效益和环境效益最优化为其目标的新型企业组织形式的过程。企业“绿色化”作为企业由经济人转变为社会人,进而向生态人演进的必然选择,必须具备五大支持系统:绿色战略、绿色企业家、绿色技术创新、绿色基金、绿色企业文化。 相似文献
570.
Christine L. Jocoy 《Journal of the American Water Resources Association》2000,36(4):811-821
ABSTRACT: Research on the condition of drinking water provision in the United States documents the inequitable financial impact of environmental regulations on small water systems (those serving 3,300 or fewer people). While a variety of federal and state financial assistance programs are available for water systems, few quantitative analyses have evaluated the success of these programs in alleviating the problems of small systems. A case study of the largest aid initiative for water supply infrastructure in Pennsylvania provides the empirical framework through which to analyze government funding opportunities for water systems. This study examines the allocation practices of the Pennsylvania Infrastructure Investment Authority (PENNVEST) to water systems of varying sizes. Utilizing data from PENNVEST applications and the Pennsylvania Department of Environmental Protection, the distribution of PENNVEST award recipients and denied applicants by size characteristics are compared. The study indicates that very small water systems (those serving 500 or fewer) do not apply for or receive funds with the same frequency as their larger counterparts. Understanding the allocation of awards from PENNVEST offers insight into the ability of small communities to access capital for water supply infrastructure. 相似文献