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1.
Predicting who may leave a fishery is an important consideration when designing capacity reduction programs to enhance both ecological and economic sustainability. In this paper, the relationship between satisfaction and the desire to exit a fishery is examined for the Queensland East Coast Trawl fishery. Income from fishing, and changes in income over the last 5 years, were key factors affecting overall satisfaction. Relative income per se was not a significant factor, counter to most satisfaction studies. Continuing a family tradition of fishing and, for one group, pride in being a fisher was found to be significant. Satisfaction with fishing overall and the challenge of fishing were found to be the primary drivers of the desire to stay or leave the fishery. Surprisingly, public perceptions of fishing, trust in management and perceptions of equity in resource allocation did not significantly affect overall satisfaction or the desire to exit the fishery.  相似文献   
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This study focuses on the verification of test interpretations for different state analyses of diffusion experiments. Part 1 of this study identified that steady, quasi-steady and equilibrium state analyses for the through- and in-diffusion tests with solution reservoirs are generally feasible where the tracer is not highly sorptive. In Part 2 we investigate parameter identifiability in transient-state analysis of reservoir concentration variation using a numerical approach. For increased generality, the analytical models, objective functions and Jacobian matrix necessary for inverse analysis of transient-state data are reformulated using unified dimensionless parameters. In these dimensionless forms, the number of unknown parameters is reduced and a single dimensionless parameter represents the sorption property. The dimensionless objective functions are evaluated for individual test methods and parameter identifiability is discussed in relation to the sorption property. The effects of multiple minima and measurement error on parameter identifiability are also investigated. The main findings are that inverse problems for inlet and outlet reservoir concentration analyses are generally unstable and well-posed, respectively. Where the tracer is sorptive, the inverse problem for the inlet reservoir concentration analysis may have multiple minima. When insufficient measurement data is collected, multiple solutions may result and this should be taken into consideration when inversely analyzing data including that of inlet reservoir concentration. Verification of test interpretation by cross-checking different state analyses is feasible where the tracer is not highly sorptive. In an actual experiment, test interpretation validity is demonstrated through consistency between theory and practice for different state analyses.  相似文献   
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The least-cost-first extraction rule for deposits with different extraction costs previously has been shown to be invalid in general equilibrium. This paper demonstrates that this rule also does not hold in partial equilibrium when extraction capacity is limited. Necessary and sufficient conditions for several surprising extraction orders are presented. If extraction from a high-cost resource is constrained, it may be optimal to begin extraction from a high-cost deposit (or backstop) strictly before extracting from a lower-cost deposit. If extraction from a low-cost resource is limited, it may be optimal to exhaust a high-cost deposit strictly before the low-cost deposit is exhausted or to abandon extraction temporarily from a high-cost deposit and then to exhaust it later. The analysis demonstrates how extraction constraints affect the order of extraction and shows that certain cost reversals are caused by limited extraction capacity rather than by the general equilibrium definition of extraction costs.  相似文献   
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Although set-up costs are prevalent and substantial in natural resource extraction, it is known that a Walrasian competitive equilibrium cannot exist in simple extraction models with set-up costs. This paper demonstrates that this result is sensitive to the assumption of unlimited extraction capacity and derives sufficient conditions for existence. An equilibrium exists if extraction is limited such that each firm earns sufficient surplus to cover its set-up costs or if firms choose extraction capacity subject to non-increasing returns. The resulting competitive equilibrium price either grows at the rate of interest when total extraction is below industry capacity or is constant when industry capacity is fully utilized. In the equilibrium, identical deposits are opened simultaneously, and set-up costs for new deposits are incurred when the industry has excess capacity rather than when capacity is fully utilized.  相似文献   
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The concept of carrying capacity is derived from ecology, with widespread contentions of its theoretical connotations and applications in the international academic community, especially the impact of human activities on the environment. Disputes on carrying capacity have been occurring not only among biologists and ecologists, but also among mainstream economists. Based on their efforts, the author makes an attempt to describe its origin, connotations, problems, measurement, and at the same time note the latest international progress in this field.  相似文献   
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Making Capacity Building Meaningful: A Framework for Strategic Action   总被引:1,自引:0,他引:1  
This paper aims to give practical meaning to ‘capacity building’ through (a) identifying a suite of practical measures, such as mentoring or best practice guidelines, that have been shown to or are considered to build human, social, institutional, and economic capital; (b) placing these measures within a broader systems framework; and (c) exploring stakeholder feedback on specific measures to inform framework implementation. The 29 measures described provide actors, whether government or nongovernment, with a suite of practical investment choices for building capacity. These measures are then clustered into eight groups according to their primary purpose and placed within a systems framework. The framework provides a tool for actors with responsibilities for or an interest in capacity building to inform more holistic and strategic targeting of effort and investment. Stakeholder feedback gathered through surveys and workshops is subsequently reported to further inform implementation of specific measures within the framework’s eight groupings. The framework presented may be built upon through the identification and inclusion of further capacity building measures. The research is conducted within the context of decentralized governance arrangements for natural resource management (NRM), with specific focus on Australia’s recently formalized 56 NRM regions and their community-based governing boards as an informative arena of learning. Application of the framework is explored in the Australian setting through the identification and comparison of measures supported and most preferred by four major stakeholder groups, namely board members, regional NRM organization staff, policy/research interests, and Indigenous interests. The research also examines stakeholder perceptions of capacity issues, and whether these issues are likely to be addressed through implementing their preferred measures.
Lisa RobinsEmail:
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8.
城市环境噪声管理的新探索——环境噪声的总量控制   总被引:1,自引:0,他引:1  
本文对目前城市环境噪声源的评价方法和管理方法作了研究和阐述,并针对其缺点提出了一种值得尝试的新方法——环境噪声的总量控制:由城市区域环境噪声标准和环境背景噪声计算出环境噪声的容量,并以此为尺度来控制噪声污染源的排放量。文中对此评价方法和管理方法作了必要的阐述和论证。  相似文献   
9.
Current demand analysis methods do not formally cover the case of chronic deficits in quantity or quality of water and sanitation services. These services include drinking water supply (DWS), wastewater and sewage treatment (WST), and municipal solid waste management (MSW). Formal analysis of this case would, at minimum, define the deficit state and evaluate appropriate options for reducing it. This paper proposes for a formal analytical model for municipal sanitation systems (MSS) that operate with deficits in at least one of the constituent services of DWS, WST, or MSW. The model introduces definitions and notation for describing the deficit state for conducting demand analysis on municipal sanitation systems. This model of demand analysis for systems with chronic deficits will hereinafter be referred to as deficit analysis. A case study for Bacoor, Philippines is presented as an example.  相似文献   
10.
A broadly defined scientific Capacity Building (CB) for Sustainable Development (SD) is needed all around the world, and the development of innovative capacities in the developing countries is a priority. For this, first we need to know how this concept is applied in some developing countries. In this paper we present some Mexican experiences in the field of capacity building for sustainable development. The main problems are the monodisciplinary training of the specialists, the absence of a sound policy for promotion, career development and assessment of researchers, as well as of their projects when they are interdisciplinary and development-oriented. The main proposals to solve these problems are the creation of mechanisms that foster and legitimize interdisciplinary work; a decentralized planning process with the specific objective of establishing the needs and orientations on a regional basis; provide resources to long-term projects, and finally, consensus on asking international funding agencies for stronger support for public higher education institutions in developing countries in order to increase and strengthen their capacity for education and research in general, and in the field of SD in particular.  相似文献   
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