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Periphytic diatoms were studied to evaluate the water quality of a newly created lake, formed by the enclosure of the formerly tidal Cardiff Bay (Wales, UK), and the effects of two inflowing rivers which drain densely populated and industrialised catchments. Seven sites in Cardiff Bay and two locations on the inflowing rivers were monitored for diatoms and water chemistry over 2 years. Water quality was assessed using a revised UK trophic diatom index (TDI) and new methods to determine ecological quality ratios and ecological status classes as required by the EU Water Framework Directive. Diatom assemblages reflected spatiotemporal variations in environmental conditions between the rivers and Cardiff Bay and within the bay. In the bay, diatoms reflected differences in river quality and possibly local pollution in certain areas of the lake. High values of the TDI indicated eutrophic to hypertrophic conditions in both rivers and in the bay and diatoms indicated poor ecological status.  相似文献   
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Single-species tests allow the assessment of chronical effects of endocrine disruptors on organisms under laboratory conditions. In the current study, three-generation tests with Ceriodaphnia reticulata and Sida crystallina were carried out to examine the influence of the synthetic hormone 17alpha-ethinylestradiol (EE) on the reproduction of these cladoceran species. For each species, six different concentrations (10-500 microg/l EE) and two controls were tested with eight replicates for a duration of 4 weeks. The test was initiated by transferring one neonate individual into a test vessel which was incubated under standardized conditions. Every 2 days, the medium was renewed and life history parameters such as survivorship of the adults and juveniles, clutch size, first appearance and number of produced offspring were investigated. Acute toxicity tests showed that C. reticulata (EC50 (24 h) 1814 microg/l) was more sensitive towards the substance compared to S. crystallina (EC50 (24 h) >4100 microg/l). The juvenile phase of S. crystallina was significantly shorter at concentrations above 100 microg/l EE. For C. reticulata, 17alpha-ethinylestradiol caused a higher mortality of the newly hatched juveniles at EE concentrations above 200 microg/l. No effects were found for mortality of adult animals, birth rate, number of juveniles per female and net reproduction rate of S. crystallina and C. reticulata. Thus, sublethal effects on parental generation exposed to EE lead to disturbances in reproduction and to affection of their offspring. Negative consequences for the population dynamic cannot be excluded, e.g. the decrease of a population.  相似文献   
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This article introduces Quality Function Deployment (QFD) as a method for improving the environmental performance of the Norwegian fishing fleet. Systems engineering has been introduced as a feasible process for handling sustainability issues in the fisheries, because it contains methods for general system design, operation, and support in a life-cycle perspective. QFD is related to systems engineering as a method for translating stakeholder needs into detailed system requirements at each life-cycle stage. Eco-QFD extends the scope of QFD, and combines QFD, Life-Cycle Cost (LCC), and Life-Cycle Analysis (LCA) to evaluate environmental effects and costs in the system development process. The article assesses the usefulness of Eco-QFD in fisheries management decision-making regarding sustainability in the fishing fleet, and for shipyards in their design of fishing vessels. It is concluded that Eco-QFD may be difficult to use for fisheries management in its present form, due to the complexity of sustainability, and the time and efforts demanded to carry out the analyses. Nevertheless, the structuring of the stakeholder needs and requirements may contribute to improved understanding of the decision-situation.  相似文献   
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