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This paper provides an analysis of the socio-economic impacts of river restoration schemes, and is novel in considering how a wide range of socio-economic variables can be used to understand impacts on the entire resident population within an area. A control-impacted approach was applied to explore differences in socio-economic characteristics of areas within which a restoration scheme had been carried out compared to areas without such a scheme. The results show that significant differences exist between control and impacted areas for a range of socio-economic variables. However, due to constraints in the methods and the data available, there are currently limitations in the extent to which socio-economic impacts of river restoration schemes can be fully explored. Additional datasets that become available in the future may increase the ability to detect associations between improvements in the water environment and socio-economic benefits. However, whilst the secondary data used in this paper are potentially powerful, they should be used alongside other techniques for assessing the impacts of decisions as part of future frameworks to deliver sustainable water management.  相似文献   
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On a mathematical interaction model, developed to model metal uptake by plants and the effects on their growth, we introduce a modification which considers also effects on variations of acidity in soil. The model relates the dynamics of the uptake of metals from soil to plants and also variations of uptake according to the acidity level. Two types of relationships are considered: total and available metal content. We suppose simple mathematical assumptions in order to get as simple as possible expressions with the aim of being easily tested in experimental problems. This work introduces modifications to two versions of the model: on the one hand, the expression of the relationship between the metal in soil and the concentration of the metal in plants and, on the other hand, the relationship between the metal in the soil and total amount of the metal in plants. The fine difference of both versions is fundamental at the moment to consider the tolerance and capacity of accumulation of pollutants in the biomass from the soil.  相似文献   
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International projects frequently struggle with the dilemmas of community participation, whether the community in question is the object of a development or aid intervention, or is to be persuaded to cooperate on a conservation project. This paper discusses the challenges facing interventionists and the obstacles and opportunities that local people encounter as they come into contact with exogenous conservation and development projects. The key issues presented can be summarized as legacy, legitimacy, agency and communication. We argue that project planners need to understand the history of past interventions in order to respond appropriately to local expectations. At the same time, the complexity of community leadership and representation complicates the sometimes conflicting agendas of project developers and communities. Much depends on personal relations, individual agency, and initiative. Finally, the physical means of communication—language, print and broadcast media, transport and telecommunications—are important aspects to consider when assessing the limitations to community participation. Although there have been valuable successes in international projects in Russia, as in other regions of the world, a better understanding of community participation is needed to ensure more effective and sustainable means for engaging communities in project development and implementation. This paper explores these questions through a locally-grounded analysis based on the academic research and practitioner experience of the two authors in the remote home of a World Heritage site—the Kamchatka Peninsula, in the Russian Far East.  相似文献   
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Parentage in emus (Dromaius novaehollandiae) was examined by microsatellite analysis using four independent loci. Of 106 chicks sampled in one breeding season from 18 nests, 54 (51%) were not fathered by the nesting male, 12 (11%) were not from the observed mate of the sitting male, and 9 (8%) represented intra-specific brood parasitism, having no alleles in common with either nest parent. Some males (11%) fathered all chicks in their nests, but the majority showed high levels of cuckoldry. Those males commencing incubation earliest in the season tended to have the highest levels of paternity in their own nests. These results reveal a high frequency of extra-pair fertilisations and resultant cuckoldry in a predominantly socially monogamous bird and support recent reports which have described the emu mating system as a complexity of polyandrous, promiscuous and monogamous behaviour. Parentage assignment of chicks resulting from extra-pair fertilisations revealed an evenly scattered pattern of paternity that did not show any particular male dominance in reproductive success. These results lead to a reassessment of behavioural observations of emus, the consequences of parentage distribution, and theories about mating systems and sexual selection. The frequency of extra-pair copulations and intra-specific brood parasitism suggests patterns of descent that differ greatly from those implied by social monogamy. Received: 27 November 1999 / Received in revised form: 8 January 2000 / Accepted: 8 February 2000  相似文献   
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The effects of monoterpenes on the degradation of 14C-2,4-dichlorophenol (DCP) were investigated in soils collected from areas surrounding monoterpene and non-monoterpene-emitting vegetation. Indigenous microorganisms degraded 14C-2,4-DCP to 14CO2, after 1 d contact time. Degradation was enhanced by prior exposure of the soils to 2,4-DCP for 32 d, increasing extents of mineralisation up to 60%. Monoterpene amendments further enhanced 2,4-DCP degradation, but only following pre-exposure to both 2,4-DCP and monoterpene, with total 2,4-DCP mineralisation extents of up to 71%. Degradation was greatest at the higher monoterpene concentrations (≥1 μg kg−1). Total mineralisation extents were similar between concentrations, but higher than the control and the 0.1 μg kg−1 amendment, indicating that increases in monoterpene concentration has a diminishing enhancing effect. We suggest that monoterpenes can stimulate the biodegradation of 2,4-DCP by indigenous soil microorganisms and that monoterpene amendment in soils is an effective strategy for removing organic contaminants.  相似文献   
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