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61.
Like many small-scale fishing communities around the world, the community of Buen Hombre in the Dominican Republic is dealing with a set of challenges to reconcile its fishing activities with the ecology on which it depends. Also like many such communities, this case has been examined at a particular period in time by a group of social scientists, but not over substantial lengths of time in order to examine the longitudinal validity of the conclusions made during this period. In this paper we combine data from previous anthropological work with our own primary social and ecological data to conduct a longitudinal case study of the Buen Hombre fishery. Our over-time comparison focuses on a suite of mostly social and institutional variables to explain what we find to be a continued degradation of the fishery, and we conclude the analysis by presenting a causal-loop diagram, summarizing our inferences regarding the complex interactions among these variables. We find that a mix of factors, notably changes in gear and fishing sites used, the number of fishermen and their livelihood diversity, as well as an increased connectivity between Buen Hombre and its external environment, have contributed to the decline of the condition of Buen Hombre coral reef fishery. We conclude with a discussion of what may lie ahead for this particular case and others like it.  相似文献   
62.
Academics and practitioners alike emphasise that public policy plays a key role to support efforts to reduce disaster risks and to buffer the impacts of natural hazards when they occur. This involves developing public policies to promote disaster risk reduction (DRR). However, the public policy dimension has only recently begun to receive attention in empirical research on DRR. Processes of policy change are discussed, yet less often studied, and more empirical research is needed to advance the understanding of the conditions for DRR policy change. Combining insights from adaptation research and public policy theory, this study investigates the long-term development of DRR policy in Mozambique as perceived by multiple stakeholders. The study identifies barriers and enabling factors influencing the DRR policy process over time. Using data from 37 semi-structured interviews, the study finds six main enabling factors supporting DRR policy change. Among the most important enabling factors are past disasters and broad stakeholder involvement. The study also unveils several barriers to DRR policy change, including resource insufficiency and lack of coordination among stakeholders. The study concludes with suggestions for integrating DRR and policy process research and lessons for policymaking in support of DRR over time.  相似文献   
63.
Integrating biodiversity conservation into forest management requires changes in the practices of those public and private actors that have implementing responsibilities and whose strategic and operational opportunities are at stake. Understanding this kind of context-dependent institutional adaptation entails bridging between two analytical approaches: policy implementation and organizational adaptation. This article combines these two approaches by reviewing them, and their caveats, and by summarizing empirical analyses of organizational competences, specialization, professional judgment, and organizational networks in the organizational field of non-industrial private forestry in Finland. Drawing on these theoretical and empirical analyses, the article discloses the broad phenomenon of institutional adaptation in the integration of biodiversity conservation and forest management. The empirical analyses point to the dominance of hierarchical policy implementation over strategic organizational adaptation. Together with the detected isomorphism of professional norms and networks, these contribute to meeting minimum standards but can constrain the ways in which the organizations and professionals respond to the challenge of biodiversity conservation. The detected inertia signals lack of alertness. It is perhaps also an indication of self-sufficiency among the actors. The interpretation of these responses to challenges and responsibilities across the public and private sector boundaries demonstrates the necessity of combining the two traditionally segregated approaches.  相似文献   
64.
Low-concentration gas transported in pipelines may lead to explosion accidents because gas with a concentration of less than 30% is prone to explode. To reduce the incidence of gas explosions, water sealing of fire barriers is implemented, and explosion venting devices are installed along the pipeline. To investigate their suppression effect on low-concentration gas explosion, experiments using methane–air premixed gas under different conditions were implemented on a DN500 pipeline test system. The effects of three types of explosion venting forms (rupture disc, asbestos board, and plastic film) on explosion overpressure and flame were compared and analysed. Results show that the rupture disc, asbestos board, and plastic film can achieve adequate explosion venting, causing the peak decay rates of explosion overpressure to reach 82.37%, 81.72%, and 90.79%, respectively. The foregoing indicates that the greater the static activation pressure of the explosion venting form, the higher the peak explosion overpressure at each measurement point. Moreover, the shorter the explosion flame duration, the greater the flame propagation velocity. The research results provide an essential theoretical foundation for the effective suppression of gas explosion accidents in the process of low-concentration gas transportation.  相似文献   
65.
为了研究狭长空间防火挡烟设施的效果,通过数值模拟方法,研究了狭长空间中两挡烟垂壁间距对烟气阻滞作用的影响规律。研究结果发现,烟气越过前挡烟垂壁后,根据烟气流动状态可分为3个流动区域,即涡旋区、涌波区和定常流动区。当后挡烟垂壁位于涌波区,挡烟垂壁间距3~6m时,阻烟效果最佳。  相似文献   
66.
Responding to the unprecedented social-environmental change facing humankind will require responsive and flexible governance institutions (i.e., systems of rules and social norms) that facilitate adaptive capacity of individuals, groups and organisations. This may explain the sustained interest in the institutional dimensions of adaptive capacity. However, a better understanding of how institutions may enable adaptive capacity is still evolving. The literature is yet to clearly articulate how institutions relate to attributes of adaptive capacity. This study contributes to address this knowledge gap; it employs an evaluative approach that underscores the relationship between types of institutions and attributes of adaptive capacity (i.e., variety, learning capacity, autonomy, leadership, resources and fair governance). Such approach is used to examine how institutions enable adaptive capacity in the context of coastal resources co-managemen in the Peam Krasaop Wildlife Sanctuary (Cambodia) and Tam Giang Lagoon (Vietnam). In this study, complexity emerges as a defining feature of adaptive capacity. It results from the relationship between institutions and adaptive capacity and the contextual factors in which such relationship takes place. Exercises aiming to assess adaptive capacity should consider the institutions-adaptive capacity nexus together with the embedding social, cultural and political context.  相似文献   
67.
Co-management of Natural Resources: A Proposed Framework   总被引:2,自引:1,他引:2  
Co-management acknowledges pragmatic developments and progression of institutional choice theories in natural resource management. This innovative concept embraces a pluralistic management approach based on the principle of subsidiarity and creates opportunities for the reconciliation of competitive property claims. This article reviews definitions of co-management, distinguishes it from other property rights regimes, and develops an organizational structure of the major elements involved. Synthesis of both experiences and literature leads to the development of a conceptual framework. Co-management is structured in terms of context, components, and linking mechanisms. In concert, these elements offer insight into the practice of co-management, address the shortcomings of institutional theories, and respond to critical issues raised in related literature. The framework contributes to natural resource management by acting as a means of identification and evaluation for such arrangements, as well as a systematic guide for future inquiries.  相似文献   
68.
Issues,impacts, and implications of shrimp aquaculture in Thailand   总被引:11,自引:0,他引:11  
Water quality impacts to and from intensive shrimp aquaculture in Thailand are substantial. Besides the surface and subsurface salinization of freshwaters, loadings of solids, oxygen-consuming organic matter, and nutrients to receiving waters are considerable when the cumulative impacts from water exchange during the growout cycle, pond drainage during harvesting, and illegal pond sediment disposal are taken into account. Although just beginning to be considered in Thailand, partial recirculating and integrated intensive farming systems are producing promising, if somewhat limited, results. By providing on-site treatment of the effluent from the shrimp growout ponds, there is less reliance on using outside water supplies, believed to be the source of the contamination.The explosion in the number of intensively operated shrimp farms has not only impacted the coastal zone of Thailand, but has also resulted in an unsustainable aquaculture industry. Abandonment of shrimp ponds due to either drastic, disease-caused collapses or more grandual, year-to-year reductions in the productivity of the pond is common. To move Thailand towards a more sustainable aquaculture industry and coastal zone environment, integrated aquaculture management is needed. Components of integrated aquaculture management are technical and institutional. The technical components involve deployment of wastewater treatment and minimal water-use systems aimed at making aquaculture operations more hydraulically closed. Before this is possible, technical and economic feasibility studies on enhanced nitrification systems and organic solids removal by oxidation between production cycles and/or the utilization of plastic pond liners need to be conducted. The integration of semi-intensive aquaculture within mangrove areas also should be investigated since mangrove losses attributable to shrimp aquaculture are estimated to be between 16 and 32% of the total mangrove area destroyed betweeen 1979 and 1993.Government policy needs to devote as much attention to sustainability issues as it has on promoting intensive pond culture. Such a balanced policy would include training and education monitoring and enforcement, rehabilitating abandoned ponds, managing land use within the coastal zone, more community involvement, and government reorganization to eliminate overlapping jurisdictions among agencies.As integrated aquaculture management becomes more the practice than the exception, less risk of crop failure to the industry and reduced discharge loadings from intensively managed shrimp ponds to receiving waters can be expected. Projected limitations on growing and marketing shrimp in the future, such as scarcity of land and broodstock, continued disease outbreaks, negative publicity, regulatory enforcement, water treatment and solids disposal costs, and increased competition from growers in other Asian countries will also drive the government and the industry towards adopting integrated aquaculture management.The data for this paper was obtained while the senior author was a Visiting Fulbright Researcher at the Coastal Resources Institute (CORIN), Prince of Songkla University, Hat Yai, Songkhla, 90112, Thailand.  相似文献   
69.
For centuries, local and indigenous water rights and rules in the Andean region have been largely neglected and discriminated against. The process of undermining local communities’ water access and control rights continues up to today and not only is it headed by powerful local, national and international water‐use actors encroaching local rights — it is also a direct consequence of vertical State law and intervention practices, and the latest privatization policies. Recognition of and security for the diverse and dynamic local rights and management frameworks is crucial for improving rural livelihoods and even national food security in Andean countries. At the request of the Government of Ecuador — in which at that time the indigenous movement had its political participation — a research mission was organized to formulate a proposal for institutional reform, aiming at the strengthening of the national irrigation sector. In this article, some basic mission results are outlined and analyzed within the scope of four concepts (institutional viability, political democracy, equity, and water rights security), and practical elements for institutional reform are suggested, not only for the Ecuadorian irrigation sector but also other settings. The complementary roles of central Government, local governments and water user organizations in water resources management are emphasized as is the need to strengthen enabling legal and policy frameworks. The importance of translating constitutional recognition of local and indigenous rights and common property systems into practical procedures and institutional structures is also stressed.  相似文献   
70.
本文运用制度变迁理论从委托代理关系-两个方面(代理成本和代理收益)对企业制变迁进行较为深入的分析,并对当前我国国有企业如何防范代理问题提出了几点建议.  相似文献   
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