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771.
In determining the importance of criteria in the management of fisheries, two key issues stand out—the definition of a succinct set of criteria and the determination of which interest groups play a defining role in the management development process. This is indeed the case for all natural resource management problems, and many other environmental problems as well. The analytic hierarchy process (AHP) provides an effective framework for such an analysis. The AHP is generally used to evaluate importance amongst criteria based on the concept of paired comparison. This paper considers the development of a representative criteria hierarchy, and uses data obtained from a pairwise comparison survey based on the UK fisheries of the English Channel to investigate priorities that exist among different interest groups in the fisheries. The implementation of the AHP in this application provides a useful tool for analysis of criteria amongst groups involved in the management process with diverse interests.  相似文献   
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Researchers attempting to integrate socio-economic data in watershed planning often draw on nationally collected census data. However, there are critical limitations to the usefulness of this type of data for decision makers operating at the watershed scale. In this paper we demonstrate the relevance of spatially referenced socio-economic data collected using mail surveys to random selections of rural landholders. The issue explored was dryland salinity management in two large watersheds in the Murray-Darling Basin of south-eastern Australia. Contrary to the assumptions underlying public policy in Australia, but consistent with the literature on farmer knowledge, comparisons of expert maps and landholder identified salinity sites suggested that landholders in these watersheds had excellent knowledge of the current extent of salinity on their property. Our research also suggested that salinity education was a sound investment by governments. At the same time, the expert maps failed to predict half of the saline affected sites identified by landholders. Accurately mapping the extent of salinity would seem a first step in addressing this nationally significant land degradation issue.  相似文献   
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A sample of 124 deserted/infertile dipper (Cinclus cinclus) eggs was collected in south-west Ireland during six seasons (1990-1994 and 1999) and analysed for mercury and organochlorines. Mercury was detected in three of the 6 years but no trend was observed. DDT occurred above the limit of detection in only two eggs, one each in 1993 and 1994. In contrast, two derivatives of DDT (DDE and TDE) were found much more commonly. DDE occurred in over 87% of eggs, while TDE contamination was less widespread and reached a maximum of 60% in 1993, with none detected in 1991 or 1999. There was no trend in occurrence of DDE or TDE across years. PCB contamination was present consistently over the 10-year period, with little change in the proportion of contaminated eggs collected over time. In all years, the lowest recorded occurrence of total PCBs was 69% expressed on a formulation basis as Arochlor 1254. PCB congeners 138, 153 and 180 dominated. The congener pattern was similar across years with the exception of 1990 when congener 118 dominated. A distinct trend of high values of contaminants was observed in 1990 and 1993. In 1990, PCB 118 was the dominant contaminant, while in 1993, HEOD, DDE, PCB 138 and PCB 153 were primary contributors to the observed result. Other contaminants (HCB, PCB 101, gamma-HCH, PCB 170 and PCB 180) showed little obvious patterns between years and occurred at relatively low levels. No pattern was observed in contaminants when eggs were grouped according to river or altitude. These data provide a baseline for organochlorine contamination levels in Irish freshwater ecosystems against which future trends can be assessed.  相似文献   
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Social capacity building for natural hazards is a topic increasingly gaining relevance not only for so-called developing countries but also for European welfare states which are continuously challenged by the social, economic and ecological impacts of natural hazards. Following an outline of recent governance changes with regard to natural hazards, we develop a heuristic model of social capacity building by taking into account a wide range of existing expertise from different fields of research. Particular attention is paid to social vulnerability and its assessment, as well as to risk communication and risk education as specific strategies of social capacity building. We propose to distinguish between interventionist and participatory approaches, thus enabling for a better understanding of existing practices of social capacity building as well as their particular strengths and weaknesses. By way of conclusion, we encourage more research on social capacity building for natural hazards in the European context which at present is highly diverse and, at least in parts, only poorly investigated.  相似文献   
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