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452.
Michael Tucker 《Environment, Development and Sustainability》2001,3(3):217-227
Northwestern United States' salmon populations have fallen precipitously. Attempts at salmon restoration are going on and dam breaching is being considered. Costs associated with the continued restoration attempts including hatchery stocking, barging and trucking salmon around the dams are high while benefits are unclear. Those costs may be greater than dam breaching. An additional impetus for dam removal is the revival of the commercial salmon fishing industry. This may not occur for both ecological and economic reasons. Ecologically complete restoration may not be feasible. Economically, the rise of competitively priced salmon aquaculture will reduce the value of any future commercial catch. A statistical relationship between falling prices for wild salmon and rising salmon aquaculture output is shown. 相似文献
453.
S.P. Kucera J.M. Swann J.R. Kennedy T.W. Schultz 《Journal of environmental science and health. Part. B》2013,48(6):779-799
Abstract The effects of the fungicide benomyl and its breakdown products, carbendazim and butyl isocyanate, were examined on canine tracheal epithelial tissue in primary culture. Changes in ciliary frequencies were monitored with an optical spectrum analysis system. Serial dilutions of the test compounds were prepared in 100% corn oil and applied to the cell cultures for intervals up to 6 hours and frequencies measured at intervals of 15 minutes to 1 hour. Benomyl and butyl isocyanate caused concentration‐dependent decreases in ciliary beat frequency. Benomyl at 300 μg/ml (3 mM) caused ciliostasis within 75 minutes of exposure. Butyl isocyanate at a molar concentration three times lower than benomyl (1 mM) caused a similar response, although within 30 minutes. The IBC50 for benomyl was 0.75 mM, while for butyl isocyanate it was 0.52 mM. Carbendazim caused a moderate decrease in frequency over a 6 hour exposure period. Benomyl caused moderate to severe swelling of the mitochondria of ciliated epithelial cells with other cell organelles appearing normal. Butyl isocyanate did not cause any noticeable effect on cell ultrastructure and the apparently low rate of penetration of carbendazim into cells made it impossible to obtain an effect which justified ultrastructural analysis. It appears, at least for benomyl and butyl isocyanate, that while the physiological effect of these two compounds (inhibition of ciliary beat) is the same, the sites of action in the cell may be different. 相似文献
454.
When an environmental sampling objective is to classify all the sample units as contaminated or not, composite sampling with selective retesting can substantially reduce costs by reducing the number of units that require direct analysis. The tradeoff, however, is increased complexity that has its own hidden costs. For this reason, we propose a model for assessing the relative cost, expressed as the ratio of total expected cost with compositing to total expected cost without compositing (initial exhaustive testing). Expressions are derived for the following retesting protocols: (i) exhaustive, (ii) sequential and (iii) binary split. The effects of both false positive and false negative rates are also derived and incorporated. The derived expressions of relative cost are illustrated for a range of values for various cost components that reflect typical costs incurred with hazardous waste site monitoring. Results allow those who are designing sampling plans to evaluate if any of these compositing/retesting protocols will be cost effective for particular applications. 相似文献
455.
As pressures on coastal zones mount, there is a growing need for frameworks that can be used to conceptualize complex sustainability challenges and help organize research that increases understand about interacting ecological and societal processes, predicts change, and supports the management, persistence, and resilience of coastal systems. The Driver–Pressure–State–Impact–Response (DPSIR) framework is one such approach that has been adopted in some coastal zones around the world. Although the application of the DPSIR framework has considerable potential to bridge the gap between scientific disciplines and link science to coastal policy and management, current applications of DPSIR in coastal environments have been limited and new innovations in the application of the DPSIR model are needed. We conducted a structured review of literature on the DPSIR framework as applied to the function, process and components of complex coastal systems. Our specific focus was on how the DPSIR framework has been used as a tool to organize sophisticated empirical scientific research, support transdisciplinary knowledge at a level appropriate for building understanding about coastal systems, and how adopting a DPSIR approach can help stakeholders to articulate and structure challenges in coastal systems and use the framework to support policy and management outcomes. The review revealed that DPSIR models of coastal systems have been largely used to support and develop conceptual understanding of coastal social–ecological systems and to identify drivers and pressures in the coastal realm. A limited number of studies have used DPSIR as a starting point for semi-quantitative or quantitative analyses, although our review highlights the continued need for, and potential of, transformative quantitative analyses and transdisciplinary applications of the DPSIR framework. The DPSIR models we reviewed were predominantly single sector, encompassing ecological or biophysical factors or focusing primarily on socio-cultural dimensions rather than full integration of both types of information. Only in eight of 24 shortlisted articles did researchers actively engage decision-makers or citizens in their research: given the potential opportunity for using DPSIR as a tool to successfully engage policy-makers and stakeholders, it appears that the DPSIR framework has been under-utilized in this regard. 相似文献
456.
457.
Emmanuel K. Mbaru Christina C. Hicks Georgina G. Gurney Joshua E. Cinner 《Conservation biology》2021,35(5):1417-1425
Many conservation interventions are hypothesized to be beneficial for both the environment and people's well-being, but this has rarely been tested rigorously. We examined the effects of adoption or nonadoption of a conservation intervention on 3 dimensions of people's well-being (material, relational, and subjective) over time. We focused on a fisheries bycatch management initiative intended to reduce environmental externalities associated with resource extraction. We collected panel data from fishers (n = 250) in villages with (adopters and nonadopters) and without (control) the conservation intervention 3 times over 2 years. We found no evidence that adoption reduced any of the 3 dimensions of well-being in the local populations affected by the intervention. There were modest improvements in material (t = –1.58) and subjective livelihood well-being (p = 0.04) for adopters relative to nonadopters over time. The variations in well-being experiences (in terms of magnitude of change) among adopters, nonadopters, and controls across the different domains over time affirmed the dynamic and social nature of well-being. 相似文献
458.
随着机械、电子器件可靠性的不断提高,系统的安全性越来越取决于人的行为。当人处于不良的精神状态,就可能做出本人意愿之外的失误,从而导致事故的发生。因此,针对人的无意识失误进行分析并提出改进措施,可以提高系统的安全水平,降低事故风险。本文提出的精神熵分析方法,以安全学原理、心理学、安全人机工程学为基础提出六个评价指标,结合熵权法的计算原理。通过班组人员岗前自评的形式,员工给出六项指标的分数,并计算自己的最终得分,以此来评估员工在岗时的精神状态。管理者依据一定原则对低分项进行询问,发现问题并提出解决办法,最终降低并控制无意识失误导致的事故风险。 相似文献
459.
Nadine Marshall Paul Marshall Ameer Abdulla 《Journal of Environmental Planning and Management》2009,52(7):901-918
The social and economic ramifications of marine conservation strategies such as marine protected areas (MPAs) are important to consider prior to their implementation to ensure that they do not exceed the resilience of resource-users and that resource protection might be maximised through compliance and low resistance. This paper presents a framework in which the human dimensions can be more easily and usefully integrated into the design and delivery of conservation initiatives. The framework espouses quantifying (1) the level of dependency on the resource; (2) perceptions towards conservation initiatives; and (3) social resilience. The framework is applied in Salum, Egypt, which is the site of a prospective MPA. 相似文献
460.
针对当前油气管道运行的现状指出第三方施工损伤风险控制的紧迫性,根据第三方施工损伤风险辨识的内容,以及油气管道第三方施工损伤风险评估中人为因素分析理论,阐述第三方施工损伤风险的影响因素,通过计算各因素的灰色关联度辨识出了第三方损伤风险的主控因素,并提出了第三方施工损伤风险控制方法. 相似文献