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In seeking to answer the question ‘who should be included in fisheries co-management?’, a constructive critique of the existing co-management literature is provided by filling the gaps of Habermas’s deliberative theory of democracy with Dewey’s pragmatism. Three conditions for ensuring democratic co-management are extrapolated from the theories: actors’ authority over decision making (empowerment), actors’ diversity (membership), and the right to self-nomination (procedures for external inclusion). The theoretical insights developed are supported with two examples of co-management institutions for inshore fisheries in the UK: Scottish Inshore Fisheries Groups (IFGs) and English Inshore Fisheries Conservation Authorities (IFCAs). 相似文献
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Two different test methods for assessing the toxicity of aminotriazole to Selenastrum capricornutum are compared. Growth medium composition is demonstrated to have a significant effect on the toxicity of aminotriazole. 相似文献
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To determine the extent of metal accumulation in some aquatic macrophytes from contaminated urban streams in southeast Queensland, plants were sampled from six sites, along with contiguous sediments. In all, 15 different species were collected, the most common genera being Typha (Cattails or Bulrushes) and Persicaria (Knotweeds). Before heavy metal analysis, plants were further separated into various morphological tissues, and five selected samples were separated into various physiological tissues. The cadmium, copper, lead and zinc content of the plants were analysed using flames AAS. In general, plant roots exhibited higher metal concentrations than the contiguous sediments. Of the metals of interest, only for zinc was there a relatively clear pattern of increasing accumulation in aquatic macrophytes with increasing sediment metal concentrations. Comparison between morphological tissues of the sampled plants found that roots consistently presented higher metal concentrations than either the stems or leaves, however unlike previous studies, this investigation revealed no consistent trend of stems accumulating more metals than the leaves. For Typha spp., metal concentrations followed the order of roots > rhizomes > leaves, while for Persicaria spp. the order was roots > leaves > stems. The submerged species Myriophyllum aquaticum accumulated the highest levels of metals overall (e.g. Zn 4300 micrograms g-1 dry weight and Cd 6.5 micrograms g-1), and the emergent macrophytes also exhibited relatively high metal contents in their roots. The leaves of the submerged and floating-leafed species collected contained relatively high quantities of the four metals of interest, compared with the leaves of emergent aquatic macrophytes. In the Typha rhizome and Persicaria stem samples analysed for internal variation in metal content, there was a pattern of increasing metal concentrations towards the external sections of the stem, both for subterranean stems (rhizomes) and above-substrate stems. For Persicaria stems, no clear pattern was observed for cadmium and lead, the two metals investigated that are not required by plants for survival. 相似文献
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The octachlorodibenzo-p-dioxin (OCDD) concentrations have been determined in aged samples of commercial pentachlorophenol (PCP), in wood protection formulations containing PCP and in wood treated with PCP as a preservative or as an anti-sapstain treatment. The concentrations of OCDD found in the various samples are within the range expected from the amount of commercial PCP initially present in the samples. In view of the known stability of OCDD the results are interpreted as indicating that the formulation, treatment and ageing processes have not led to any substantial conversion of PCP to OCDD; although one result indicates that outdoor exposure of treated samples increased the OCDD concentration by a factor of approximately 2 after years. Analysis of aged samples of treated wood indicate that OCDD is lost much less rapidly from the wood than PCP. 相似文献
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Richard N. Palmer Hal E. Cardwell Mark A. Lorie William Werick 《Journal of the American Water Resources Association》2013,49(3):614-628
Participatory planning applied to water resources has sparked significant interest and debate during the last decade. Recognition that models play a significant role in the formulation and implementation of design and management strategies has encouraged the profession to consider how such models can be best implemented. Shared Vision Planning (SVP) is a disciplined planning approach that combines traditional water resources planning methodologies with innovations such as structured public participation and the use of collaborative modeling, resulting in a more complete understanding and an integrative decision support tool. This study reviews these three basic components of SVP and explains how they are incorporated into a unified planning approach. The successful application of SVP is explored in three studies involving planning challenges: the National Drought Study, the Lake Ontario‐St. Lawrence River Study, and the Apalachicola‐Chattahoochee‐Flint/Alabama‐Coosa‐Tallapoosa River Basin Study. The article concludes by summarizing the advantages and limitations of this planning approach. 相似文献
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The results of analyses for polychlorodibenzofuran (PCDF) content in two samples of polychlorobiphenyl (PCB) from used electrical transformers are presented and discussed. In neither sample was there evidence for enhanced PCDF concentrations even though one of them had been subjected to overheating while in service. 相似文献
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Results of analyses of eight samples of technical pentachlorophenol conducted by three different analytical methods are presented and discussed. 相似文献
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Wood samples treated with technical pentachlorophenol (PCP), technical sodium pentachlorophenoxide (NaPCP) and octachlorodibenzo-p-dioxin have been exposed outdoors for periods up to years. Analysis of extracts from the samples show that photolytic reductive dechlorination of highly chlorinated dibenzo-p-dioxins to less chlorinated isomers occurs. However there is no discernible increase in polychlorodibenzo-p-dioxin concentrations in the technical PCP treated wood presumably because further photolytic reactions and volatilisation compete effectively with the photolytic formation. There is no evidence for formation of octachlorodibenzo-p-dioxin (OCDD) in technical PCP treated wood in this study, probably because photolytic destruction and volatilisation compete effectively with formation reactions when the initial OCDD concentration is relatively high. 相似文献