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91.
Perceptions of Community Benefits from Two Wild and Scenic Rivers   总被引:1,自引:0,他引:1  
Wild and Scenic Rivers provide a host of psychological, social, ecological, and economic benefits to local communities. In this study, we use data collected from recreational users of two Wild and Scenic Rivers to examine perceptions of the benefits provided by the rivers to local communities. Our purposes are (1) to determine if similar perceptions of community benefits exist across the two rivers, (2) to determine if individuals’ proximity to the rivers are related to the benefits they perceive, (3) to determine if individuals’ prior recreation experience on the river is related to variations in perceived benefits, (4) to determine if users’ sociodemographic characteristics are related to perceived community benefits, and (5) to determine if the influence of these characteristics on perceived community benefits is similar across the two resource areas. Perceived benefits were found to be analogous across both rivers as individuals consistently ranked ecological/affective benefits as well as tangible benefits similarly. Recreationists living further from the river ranked ecological and affective benefits as significantly less important than those individuals living closer to the river. Women perceived the community benefits produced by the resource areas to be significantly more important when compared to men. Significant relationships were also found between perceived benefits and recreationists’ previous use of the river, their age, and their level of education. With the exception of resource proximity and prior use history, the effects of user characteristics on perceived community benefits were not statistically different across the two rivers. These findings imply similar patterns of perceived community benefits exist across distinct resource areas and that the relationships between user characteristics and perceived benefits are also similar across the study rivers.  相似文献   
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93.
ABSTRACT

This paper employs qualitative content analysis to assess 28 brownfield redevelopment plans produced as part of a US Environmental Protection Agency programme. The analysis framework followed the economic, ecological, and social equity dimensions of sustainable development. The findings illustrate that, in terms of economic dimensions, most plans discussed financing the overall project, but few mentioned site values or the pivotal cost of remediating brownfield sites or addressed questions related to liability, the transfer of ownership of sites, or the end use of remediated sites. In terms of ecological dimensions, while many plans suggested “green” uses of existing brownfields, few discussed the impacts of the plans on urban ecological issues or offered technical feasibility of remediating the sites. In terms of social equity dimensions, half of the plans described potential local jobs stemming from the proposed redevelopment, but many did not discuss the human impacts of remediating contaminated sites or the costs of doing nothing. Most plans mentioned community engagement methods but not their outcomes, making the degree to which the lessons gleaned from such engagement influenced the plans totally unclear. Despite the programme’s explicit focus on the nexus of environmental justice and local environments, many plans struggled to address the topic in favour of tackling broader economic, environmental, and equity issues. Overall, this paper contributes to the understanding of brownfield redevelopment planning by not only summarising and synthesising the tendencies of existing plans but also suggesting strategies to address areas in which current planning efforts fall short.  相似文献   
94.
Depletion of plant-available soil phosphorus (P) from excessive to agronomically optimum levels is a measure being implemented in Ireland to reduce the risk of diffuse P transfer from land to water. Within the Nitrates and Water Framework Directive regulations the policy tool is designed to help achieve good status by 2015 in water bodies at risk from eutrophication. To guide expectation, this study used soil plot data from eight common soil associations to develop a model of Soil Test P (STP) (Morgan's extract) decline following periods of zero P amendment. This was used to predict the time required to move from excessive (Index 4) to the upper boundary of the optimum (Index 3) soil P concentration range. The relative P balance (P balance : Total soil P) best described an exponential decline (R2 = 63%) of STP according to a backwards step-wise regression of a range of soil parameters. Using annual field P balance scenarios (?30 kg P ha?1, ?15 kg P ha?1, ?7 kg P ha?1), average time to the optimum soil P boundary condition was estimated from a range of realistic Total P and STP starting points. For worst case scenarios of high Total P and STP starting points, average time to the boundary was estimated at 7–15 years depending on the field P balance. However, uncertainty analysis of the regression parameter showed that variation can be from 3 to >20 years. Combined with variation in how soil P source changes translate to resulting P delivery to water bodies, water policy regulators are advised to note this inherent uncertainty from P source to receptor with regard to expectations of Water Framework Directive water quality targets and deadlines.  相似文献   
95.
Marine fisheries in coastal ecosystems in many areas of the world have historically removed large-bodied individuals, potentially impairing ecosystem functioning and the long-term sustainability of fish populations. Reporting on size-based indicators that link to food-web structure can contribute to ecosystem-based management, but the application of these indicators over large (cross-ecosystem) geographical scales has been limited to either fisheries-dependent catch data or diver-based methods restricted to shallow waters (<20 m) that can misrepresent the abundance of large-bodied fished species. We obtained data on the body-size structure of 82 recreationally or commercially targeted marine demersal teleosts from 2904 deployments of baited remote underwater stereo-video (stereo-BRUV). Sampling was at up to 50 m depth and covered approximately 10,000 km of the continental shelf of Australia. Seascape relief, water depth, and human gravity (i.e., a proxy of human impacts) were the strongest predictors of the probability of occurrence of large fishes and the abundance of fishes above the minimum legal size of capture. No-take marine reserves had a positive effect on the abundance of fishes above legal size, although the effect varied across species groups. In contrast, sublegal fishes were best predicted by gradients in sea surface temperature (mean and variance). In areas of low human impact, large fishes were about three times more likely to be encountered and fishes of legal size were approximately five times more abundant. For conspicuous species groups with contrasting habitat, environmental, and biogeographic affinities, abundance of legal-size fishes typically declined as human impact increased. Our large-scale quantitative analyses highlight the combined importance of seascape complexity, regions with low human footprint, and no-take marine reserves in protecting large-bodied fishes across a broad range of species and ecosystem configurations.  相似文献   
96.
Cadmium (Cd) is a carcinogenic metal contaminating the environment and ending up in wastewaters. There is therefore a need for improved methods to remove Cd by adsorption. Biogenic elemental selenium nanoparticles have been shown to adsorb Zn, Cu and Hg, but these nanoparticles have not been tested for Cd removal. Here we studied the time-dependency and adsorption isotherm of Cd onto biogenic elemental selenium nanoparticles using batch adsorption experiments. We measured ζ-potential values to assess the stability of nanoparticles loaded with Cd. Results show that the maximum Cd adsorption capacity amounts to 176.8 mg of Cd adsorbed per g of biogenic elemental selenium nanoparticles. The ζ-potential of Cd-loaded nanoparticles became less negative from ?32.7 to ?11.7 mV when exposing nanoparticles to an initial Cd concentration of 92.7 mg L?1. This is the first study that demonstrates the high Cd uptake capacity of biogenic elemental selenium nanoparticles, of 176.8 mg g?1, when compared to that of traditional adsorbents such as carboxyl-functionalized activated carbon, of 13.5 mg g?1. An additional benefit is the easy solid–liquid separation by gravity settling due to coagulation of Cd-loaded biogenic elemental selenium nanoparticles.  相似文献   
97.
Internet-based research is increasingly important for conservation science and has wide-ranging applications and contexts, including culturomics, illegal wildlife trade, and citizen science. However, online research methods pose a range of ethical and legal challenges. Online data may be protected by copyright, database rights, or contract law. Privacy rights may also restrict the use and access of data, as well as ethical requirements from institutions. Online data have real-world meaning, and the ethical treatment of individuals and communities must not be marginalized when conducting internet-based research. As ethics frameworks originally developed for biomedical applications are inadequate for these methods, we propose that research activities involving the analysis of preexisting online data be treated analogous to offline social science methods, in particular, nondeceptive covert observation. By treating internet users and their data with respect and due consideration, conservationists can uphold the public trust needed to effectively address real-world issues.  相似文献   
98.
Marine resource management programs face conflicting mandates: to scale-up marine conservation efforts to cover larger areas and meet national and international conservation targets, while simultaneously to downscale and decentralize management authority to resource users and local communities. These conflicting goals create tensions in marine resource management. This paper explores these tensions by presenting and evaluating the outcomes of a fisheries co-management program on the island of Pemba, Tanzania, where institutions and scale were configured and reconfigured under externally funded programs to improve marine conservation through co-management. The initial institutional arrangements for co-management supported a functioning system to protect marine resources, ensure fishermen’s access, and distribute tourism revenues. However, a subsequent push to scale-up marine management reconfigured institutional arrangements and power in a more hierarchical and potentially weaker system. With the expansion of the co-management program, protected area coverage, financial resources, and the number of community organizations created for fisheries co-management expanded tremendously; however, community participation in marine management decreased, and the fishermen’s association previously involved in co-management dissolved. Several factors contributed to this outcome: inadequate time to solidify co-management institutions and arrangements, diverse resource users inexperienced with local management, a sudden and substantial new source of funding, and political pressures to restructure marine management. Rather than focusing primarily on expanding coverage and devolving authority, it is important to adapt co-management arrangements to the local contexts in which they operate.  相似文献   
99.
A fresh perspective on policy-making and planning has emerged which views disproportionate policy as an intentional policy response. A disproportionate policy response is understood to be a lack of ‘fit’ or balance between the costs of a public policy and the benefits that are derived from this policy, and between policy ends and means. This paper applies this new perspective on the proportionality of policy-making to the area of climate change. The first part of the paper discusses the underlying causes of disproportionate policy responses in broad terms and then applies the theoretical reasoning to understand the conditions in which they are likely to appear in relation to climate change. These conditions are hypothesized to relate to four main factors: economic considerations; levels of public demand; focusing events; and strategic considerations. It concludes with the suggestion that societal actors may be able to manipulate these four factors to encourage politicians to adopt policies that mitigate climate change more rapidly than is currently the case in most countries.  相似文献   
100.
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