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Ryon MG 《Environmental management》2011,47(6):1096-1111
The long-term recovery process for fish communities in a warm water stream in East Tennessee was studied using quantitative
measurements over 20 years. The stream receives effluents from a U. S. Department of Energy (DOE) facility, but since 1985
these effluents have been greatly reduced, eliminated, or diluted as part of a substantial long-term pollution abatement program.
The resulting changes in water quantity and quality led to a recovery of the fish communities, evidenced by significant changes
in species richness, abundance (density and biomass), and community composition (e.g., number of fish species sensitive to
stress). The fish community changes occurred over a spatial gradient (downstream from the headwater release zone nearest the
DOE facility) and temporally, at multiple sampling locations in the stream. Changes in measured parameters were associated
with specific remedial actions and the intervening steps within the recovery process are discussed with regard to changes
in treatment processes. 相似文献
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邛海水质变化趋势及保护对策研究 总被引:1,自引:0,他引:1
本文通过对邛海流域现状污染源进行调查,邛海流域COD、氨氮、总氮和总磷产生量分别为5892.1t/a、995.6t/a、2888.2t/a和1105.1t/a,污染负荷主要来自面源污染.通过2002 ~ 2011年邛海水质监测数据分析,邛海水质近10年总体保持Ⅱ~Ⅲ类,处于中营养状态,2004~ 2006年水质相对较差,2006年以后水质逐渐好转.总磷、总氮是邛海主要污染因子,海河口是邛海污染最严重的区域.为实现邛海水质和流域生态环境持续改善,从产业结构优化、流域污染源治理、生态保育和流域生态环境综合监管等方面提出对策建议. 相似文献
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Karianne Kalshoven Franck L. B. Meijboom 《Journal of Agricultural and Environmental Ethics》2013,26(1):101-117
Sustainability and welfare are concepts that are often mentioned in the context of fishing and fish farming. What these concepts imply in practice, how they are defined and made operational is less clear. This paper focuses on the role of fish buyers as a key actor in the supply chain between the fisher or fish farmer and the consumer. Using semi-structured interviews, we explore and analyze whether and how the interviewed fish buyers define and implement moral values related to animal welfare and sustainability. The eight fish buyers who were interviewed suggest that moral values are used in their work, but also result in a number of value conflicts (moral and non-moral). The focus on sustainability and animal welfare appear to be driven by external and market factors. Sustainability mainly reflects fishing methods and quotas and fish welfare is seen as part of sustainability. Fish welfare seems more important for farmed than for wild fish as the buyers feel a responsibility regarding these kept animals. Further, the decision whether a product is sustainable is mainly based on labels. Fish buyers argue that labels are useful as a business-to-business tool. Nonetheless, based on the interviews, we argue that the relevance of these labels for addressing the ethical dilemmas of buyers is limited. Labels often are a rather procedural solution that deals with the genuine dilemmas only to a limited extent. We conclude that in order to move forward, the sector needs to further reflect and elaborate on its core values. 相似文献
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More of the Same: High Functional Redundancy in Stream Fish Assemblages from Tropical Agroecosystems 总被引:1,自引:0,他引:1
Lilian Casatti Fabrício Barreto Teresa Jaquelini de Oliveira Zeni Mariela Domiciano Ribeiro Gabriel Lourenço Brejão Mônica Ceneviva-Bastos 《Environmental management》2015,55(6):1300-1314
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Depleting Fish Resources,Declining Fishing Communities,and the State Revitalization Project in Korea
Cheong SM 《Environmental management》2003,32(3):382-390
This paper reviews recent declines in fish resources and fishing communities in Korea, evaluates major factors of declines, and examines a subsequent community-based revitalization project. Factors leading to depleting fish resources include global regulations, technological advances in fishing, national economic development policies, land reclamation projects, and pollution. The negative economic and societal impact of depleting fish resources is addressed using demographic and income levels of the communities. In response, the state initiated revitalization projects and invested in local fishing cooperatives promoting community-based management. The result has been less than effective as it led to mismanagement of investment and created an attitude of dependence on the government for financial assistance. 相似文献
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Elizabeth Wilson 《Local Environment》2006,11(6):609-625
Climate change is a major issue for all levels of government, global, national and local. Local authorities' responses to climate change have tended to concentrate on their role in reducing greenhouse gases. However, the scientific consensus is that we also need to adapt to unavoidable climate change. Spatial planning at a local level has a critical anticipatory role to play in promoting robust adaptation. This paper reviews the shift in local authorities' planning policies for climate change adaptation in the UK since 2000, and provides evidence of underlying attitudes amongst planning professionals to climate change. It shows that, while the issue of climate change is becoming recognized with respect to flood risk, the wider implications (for instance, for biodiversity and water resources) are not yet integrated into plans. The reasons for this lie in lack of political support and lack of engagement of the planning profession with climate change networks. But the paper also argues there are difficulties in acknowledging the need for adaptation at the local level, with the short-term horizons of local plans at odds with perceptions of the long-term implications of climate change. 相似文献
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A landscape-level approach was applied to eight rural watersheds to assess the role that wetlands play in reducing phosphorus loading to surface waters in the Lake Champlain Basin. Variables summarizing various characteristics of wetlands within a watershed were calculated using a geographic information system and then compared to measured phosphorus loading through multiple regression analyses. The inclusion of a variable based on the area of riparian wetlands located along low- and medium-order streams in conjunction with the area of agricultural and nonwetland forested lands explained 88% of the variance in phosphorus loading to surface waters. The best fit model coefficients (Pload = 0.86Ag + 0.64For – 30Ripwet + 160) suggest that a hectare of riparian wetland may be many times more important in reducing phosphorus than an agricultural hectare is in producing phosphorus. These results provide additional support for the concept that protection of riparian wetlands is an important management strategy for controlling stream water quality in multiuse landscapes. 相似文献
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Abstract: Stream and riparian managers must effectively allocate limited financial and personnel resources to monitor and manage riparian ecosystems. They need to use management strategies and monitoring methods that are compatible with their objectives and the response potential of each stream reach. Our objective is to help others set realistic management objectives by comparing results from different methods used to document riparian recovery across a diversity of stream types. The Bureau of Land Management Elko Field Office, Nevada, used stream survey, riparian proper functioning condition (PFC) assessment, repeat photographic analysis, and stream and ecological classification to study 10 streams within the Marys River watershed of northeast Nevada during all or parts of 20 years. Most riparian areas improved significantly from 1979 to 1992‐1993 and then additionally by 1997‐2000. Improvements were observed in riparian and habitat condition indices, bank cover, and stability, pool quality, bank angle, and depth of undercut bank. Interpretation of repeat photography generally confirmed results from stream survey and should be part of long‐term riparian monitoring. More attributes of Rosgen stream types C and E improved than of types B and F. A and Gc streams did not show significant improvement. Alluvial draws and alluvial valleys improved in more ways than V‐erosional canyons and especially V‐depositional canyons. Stream survey data could not be substituted for riparian PFC assessment. Riparian PFC assessments help interpret other data. 相似文献
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青海湖主要旅游景区旅游环境承载力研究 总被引:1,自引:0,他引:1
文章测算了青海湖鸟岛和151景区的年、月、节假日游览环境承载力,作出了评价,并对可能出现旅客满载、超载的情况提出了对策和建议。 相似文献
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This article stresses the importance of within-government capacity build as the optimal approach to minimizing landslide risk
to the most vulnerable communities in the developing world. Landslide risk is an integrated issue that demands strong managerial
leadership and multidisciplinary inclusion to develop structures that deliver sustainable improvements in the reduction of
risk. The tension between projects demanding international technical and financial intervention and those capable of “within-country”
solutions are examined. More particularly, the challenges of developing a management methodology capable of energizing inter-ministry
collaboration to achieve community-level action is examined in the context of a recently established program of slope stability
management in St. Lucia. The program, Management of Slope Stability in Communities (MoSSaiC), is shown to have successfully
fostered not only extensive technical collaboration within government but also to have energized local communities in the shared mission of capacity build through their direct involvement
in the management process. 相似文献
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Hatcheries have long been used in an attempt to mitigate for declines in wild stocks of Pacific salmon (Oncorhynchus spp.), though the conservation benefit of hatcheries is a topic of ongoing debate. Irrespective of conservation benefits, a fundamental question is whether hatcheries will be able to function as they have in the past given anticipated future climate conditions. To begin to answer this question, we developed a deterministic modeling framework to evaluate how climate change may affect hatcheries that rear Pacific salmon. The framework considers the physiological tolerances for each species, incorporates a temperature-driven growth model, and uses two metrics commonly monitored by hatchery managers to determine the impacts of changes in water temperature and availability on hatchery rearing conditions. As a case study, we applied the model to the US Fish and Wildlife Service’s Winthrop National Fish Hatchery. We projected that hatchery environmental conditions remained within the general physiological tolerances for Chinook salmon in the 2040s (assuming A1B greenhouse gas emissions scenario), but that warmer water temperatures in summer accelerated juvenile salmon growth. Increased growth during summer coincided with periods when water availability should also be lower, thus increasing the likelihood of physiological stress in juvenile salmon. The identification of these climate sensitivities led to a consideration of potential mitigation strategies such as chilling water, altering rations, or modifying rearing cycles. The framework can be refined with new information, but in its present form, it provides a consistent, repeatable method to assess the vulnerability of hatcheries to predicted climate change. 相似文献
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JOSEPH L. EBERSOLE WILLIAM J. LISS CHRISTOPHER A. FRISSELL 《Environmental management》1997,21(1):1-14
/ Ecological restoration is increasingly invoked as a tool for the maintenance and regeneration of biodiversity. Yet the conceptual foundations and assumptions underlying many restoration management activities are frequently unclear or unstated. Unforeseen, undesirable consequences of restoration activities may emerge as a result. A general conceptual framework for restoration is needed to better accommodate dynamic habitat systems and evolving biota in restoration strategies. A preliminary framework for stream habitat restoration emphasizing stream habitat-biota development is proposed. As developing systems, streams and stream biota exhibit temporal behaviors that change with stream environments. Underlying the dynamic development of streams is potential capacity. Streams express this capacity as an array of habitats over time and across the landscape. Human land uses in the western United States have rapidly altered aquatic habitats and the processes that shape habitat. As a result, the diversity of native fishes and their habitats has been suppressed. Restoration is fundamentally about allowing stream systems to reexpress their capacities. Several steps are provided to guide stream restoration activities. Key tasks include: identification of the historic patterns of habitat development; identification of developmental constraints; relief of those constraints; classification of sensitive, critical, or refuge habitats; protection of the developmental diversity that remains; and monitoring of biotic responses to habitat development. KEY WORDS: Stream habitat; Stream biota; System capacity; System development; Restoration; Classification 相似文献
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Rubens S. Gondim Marco A.H. de Castro Aline de H.N. Maia Sílvio R.M. Evangelista Sérgio C. de F. Fuck 《Journal of the American Water Resources Association》2012,48(2):355-365
Gondim, Rubens S., Marco A.H. de Castro, Aline de H.N. Maia, Sílvio R.M. Evangelista, and Sérgio C. de F. Fuck, Jr., 2012. Climate Change Impacts on Irrigation Water Needs in the Jaguaribe River Basin. Journal of the American Water Resources Association (JAWRA) 48(2): 355‐365. DOI: 10.1111/j.1752‐1688.2011.00620.x Abstract: Climate change is conceptually referred to as a modification to the average of climate variables and their natural variability, due to both natural and anthropogenic driving forces, such as greenhouse gas emissions. Climate change potentially impacts rainfall, temperature, and air humidity, which have relationship with plant evapotranspiration and consequently to irrigation water needs (IWN). The purpose of this research is to assess climate change impacts on irrigation water demand, based on climatic impacts stemming from future greenhouse gas emission scenarios. The study area includes eight municipalities in the Jaguaribe River Basin, located in the Ceará State of semiarid northeast Brazil. The FAO Penman‐Monteith method is used for the calculation of a reference evapotranspiration with limited climatic data. IWN projections are calculated using bias‐corrected climate projections for monthly rainfall and surface temperature derived from the United Kingdom’s Hadley Centre Regional Climate Model simulations. The increase in the average IWN is projected to be 7.9 and 9.1% over the period 2025‐2055 for the A2 and B2 scenarios, respectively with respect to 1961‐1990 baseline. 相似文献