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261.
Pamela A. Heidell Paul H. Kirshen 《Journal of the American Water Resources Association》1982,18(1):105-110
ABSTRACT: The potential for hydroelectric power development at existing dams is great in oil dependent New England where there are over 10,000 dams presently in existence. Over 400 developments have been proposed in the region, the majority of which are small scale, and do not have major environmental impacts. Nevertheless, a variety of constraints may hinder development. A study of three efforts by municipalities in unique positions to develop hydropower reveals that organizational and political considerations are significant factors affecting development. Successful hydropower development requires: (1) the cooperation and interaction of citizens, government, and the private sector; (2) community interest and education; and (3) strong resolve. 相似文献
262.
Albrecht Hase R. Hesse Adolf Mayer Paul Weiss Karl Bělař 《Die Naturwissenschaften》1929,17(44):863-866
263.
Olen Paul Matthews 《Environmental management》1988,12(4):413-427
The Supreme Court's interpretation of the commerce clause controls the balance of power between state and federal governments in the United States. An understanding of the relationship between the different government levels is essential for resource managers concerned with resource and environmental issues. This study examines selected Supreme Court decisions between 1976 and 1988 to answer three questions raised by the commerce clause: (1) Is the regulated item an article of commerce? (2) Do state laws burden interstate commerce? (3) Is federal commerce regulation limited? The balance of power among the justices and the commerce clause theories affecting the federal role in resource management are also examined. Since ratification of the Constitution, the Supreme Court has continuously increased federal power, but states have power to act independently as long as contradictory federal laws do not exist and state law does not impermissively affect commerce. If Congress regulates an individual's use of resources, their power is unquestioned. Future Court decisions will not significantly reduce the federal role in resource management even if the Court's membership changes. Even the supporters of states' rights on the Court realize increased federal power is a necessary part of the country's evolution. The purpose of the commerce clause is to create a national economic unit with free location principles. The Court supports this purpose today and will in the future. 相似文献
264.
Geotechnical and leaching properties of flowable fill incorporating waste foundry sand 总被引:1,自引:0,他引:1
Waste foundry sand (WFS) can be converted into flowable fill for geotechnical applications. In this study, WFS samples were obtained from 17 independent metal casting facilities with different casting processes, thus representing a good range of WFS properties. The laboratory studies include physical, geotechnical and leaching properties of flowable fills consisting of WFS, cement, and fly ash mixed to different water contents. The main properties measured include WFS physical properties (density, particle gradation, grain shape, and fine content), WFS flowable fill geotechnical properties (unconfined compressive strength, hydraulic conductivity, setting time, and bleeding), and the fill's leaching properties (heavy metals and organics in the bleed water and the leachate extracted from hardened WFS flowable fills). The test results indicate that in terms of the physical properties, most of the data fall within narrow ranges, although data from the copper/aluminum-based WFS samples might fall beyond the ranges. Geotechnical properties of WFS flowable fills in both fresh and hardened phases were verified conforming to the features of specified flowable fills. Material leaching analyses indicate that the toxicity of WFS flowable fills is below regulated criteria. A mix formulation range originated from this study is proposed for the design of WFS made flowable fill. 相似文献
265.
266.
Maria Lumbierres Prabhat Raj Dahal Moreno Di Marco Stuart H. M. Butchart Paul F. Donald Carlo Rondinini 《Conservation biology》2022,36(3):e13851
Area of habitat (AOH) is defined as the “habitat available to a species, that is, habitat within its range” and is calculated by subtracting areas of unsuitable land cover and elevation from the range. The International Union for the Conservation of Nature (IUCN) Habitats Classification Scheme provides information on species habitat associations, and typically unvalidated expert opinion is used to match habitat to land-cover classes, which generates a source of uncertainty in AOH maps. We developed a data-driven method to translate IUCN habitat classes to land cover based on point locality data for 6986 species of terrestrial mammals, birds, amphibians, and reptiles. We extracted the land-cover class at each point locality and matched it to the IUCN habitat class or classes assigned to each species occurring there. Then, we modeled each land-cover class as a function of IUCN habitat with (SSG, using) logistic regression models. The resulting odds ratios were used to assess the strength of the association between each habitat and land-cover class. We then compared the performance of our data-driven model with those from a published translation table based on expert knowledge. We calculated the association between habitat classes and land-cover classes as a continuous variable, but to map AOH as binary presence or absence, it was necessary to apply a threshold of association. This threshold can be chosen by the user according to the required balance between omission and commission errors. Some habitats (e.g., forest and desert) were assigned to land-cover classes with more confidence than others (e.g., wetlands and artificial). The data-driven translation model and expert knowledge performed equally well, but the model provided greater standardization, objectivity, and repeatability. Furthermore, our approach allowed greater flexibility in the use of the results and uncertainty to be quantified. Our model can be modified for regional examinations and different taxonomic groups. 相似文献
267.
Local Agenda 21 (LA21) has emerged as the principal means of addressing sustainable development practice at the local government level. In the UK, progressive local authorities have emphasised the need for participatory processes and innovative policy options. This requires commitment and active involvement from a variety of individuals and organisations. Participants in LA21 have been interviewed to determine their motivations and perceptions, and their responses are represented in terms of the storylines of various constituencies of interest. The key themes seem to be those of actively promoting widespread participation, gaining competence in innovative techniques, taking a holistic approach to quality of life concerns, and claiming the legitimacy of local government as a key player in sustainable development. 相似文献
268.
Paul J. Favara Todd M. Krieger Bob Boughton Angela S. Fisher Mohit Bhargava 《补救:环境净化治理成本、技术与工艺杂志》2011,21(3):39-79
The US Sustainable Remediation Forum (SURF) proposes a nine‐step process for conducting and documenting a footprint analysis and life‐cycle assessment (LCA) for remediation projects. This guidance is designed to assist remediation practitioners in evaluating the impacts resulting from potential remediation activities so that preventable impacts can be mitigated. Each of the nine steps is flexible and scalable to a full range of remediation projects and to the tools used by remediation practitioners for quantifying environmental metrics. Two fictional case studies are presented to demonstrate how the guidance can be implemented for a range of evaluations and tools. Case‐study findings show that greater insight into a study is achieved when the nine steps are followed and additional opportunities are provided to minimize remediation project footprints and create improved sustainable remediation solutions. This guidance promotes a consistent and repeatable process in which all pertinent information is provided in a transparent manner to allow stakeholders to comprehend the intricacies and tradeoffs inherent in a footprint analysis or LCA. For these reasons, SURF recommends that this guidance be used when a footprint analysis or LCA is completed for a remediation project. © 2011 Wiley Periodicals, Inc. 相似文献
269.
Paul Harvey 《Disasters》1998,22(3):200-217
The paper examines the challenge of rehabilitation from complex political emergencies (CPEs) and identifies a strategy that is characterised as a civil society rebuilding approach. It focuses on Somalia and a case study of a CARE project that aims to build the capacity of local NGOs. The paper argues that civil society in CPEs is simultaneously being undermined and contested by warring parties and emerging after state collapse. The scope of the paper is limited to one case study and that case study examines only a single aspect of civil society: national and international NGOs. The paper therefore presents tentative and preliminary results based on limited research. However, in reviewing the literature and presenting a way of approaching the subject, it aims to suggest a starting-point for developing a theoretical framework for such research. The paper finds that international agencies have tended to focus on civil society institutions simply as conduits for aid money and that this has tended to create organisations which lack downward accountability, are dependent on donors and are not addressing the wider roles for civil society envisaged in the approach. Rebuilding civil society does hold out the promise of giving non-military interests a stronger voice and starting a process of changing the aid delivery culture. Achieving these objectives, however, will be a slow and largely indigenous process and there is a need for lowered expectations about what outside assistance can achieve 相似文献
270.