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991.
We conducted case studies of three successful examples of collaborative, community-based natural resource conservation and development. Our purpose was to: (1) identify the functions served by interactions within the social networks of involved stakeholders; (2) describe key structural properties of these social networks; and (3) determine how these structural properties varied when the networks were serving different functions. The case studies relied on semi-structured, in-depth interviews of 8 to 11 key stakeholders at each site who had played a significant role in the collaborative projects. Interview questions focused on the roles played by key stakeholders and the functions of interactions between them. Interactions allowed the exchange of ideas, provided access to funding, and enabled some stakeholders to influence others. The exchange of ideas involved the largest number of stakeholders, the highest percentage of local stakeholders, and the highest density of interactions. Our findings demonstrated the value of tailoring strategies for involving stakeholders to meet different needs during a collaborative, community-based natural resource management project. Widespread involvement of local stakeholders may be most appropriate when ideas for a project are being developed. During efforts to exert influence to secure project approvals or funding, however, involving specific individuals with political connections or influence on possible sources of funds may be critical. Our findings are consistent with past work that has postulated that social networks may require specific characteristics to meet different needs in community-based environmental management.  相似文献   
992.
This paper develops a method for identifying and assessing long-term supply risks for mineral raw materials. The method is based on a combined evaluation of past and future supply and demand trends. By analysing raw material boom and bust cycles over the past 50 years, we have quantified indicators and defined benchmarks for identifying critical market situations. By applying the method, risks for supply shortage may be identified at an early stage. In addition, a numerical evaluation model has been developed for better comparison between various mineral raw materials. Compared to other assessment methods this method uses specific benchmarks for each raw material to better assess supply risks. The method is embedded within a systematic and comprehensive analytical approach.  相似文献   
993.
Rhododendron ponticum is an invasive species in many countries, including the United Kingdom, Ireland, Belgium, and France. It poses a serious threat to native flora and fauna, as it is capable of altering entire seminatural communities through its vigorous spread. Control is essential if the conservation value of some communities, such as oak woodland and lowland heath, are to be successfully maintained. Commonly used interventions are herbicide application, herbicide application postcut, and cutting (manual or mechanical) alone. Various techniques have been developed to apply these interventions, but often retreatment of the area is required, increasing the cost of control. Here, we evaluate the effectiveness of some commonly used interventions for R. ponticum control using a systematic review methodology. Eleven studies provided data for statistical analysis. Meta-analyses of captured data show that postcut application of the herbicide Glyphosate or applying the herbicides Metsulfuron-methyl or Imazapyr (no cut) can effectively reduce a R. ponticum stand. There is insufficient available experimental evidence for effectiveness of any other intervention. The systematic review process has demonstrated the lack of replicated studies with controls or long-term monitoring and increases the call for more rigorous monitoring of all conservation management interventions. The quality of experimental evidence of the effectiveness of some interventions contrasts with the acceptance of their use through dissemination of experience. The collection and objective review of experience will require active collaboration of organizations concerned with R. ponticum control.  相似文献   
994.
  总被引:1,自引:0,他引:1  
The article outlines the development of Iceland's fishery rights and the extension of its territorial waters between the 1950s and the mid‐1970s, whereby Iceland gained exclusive control and use of the marine resources of the waters within 12, later 50, and ultimately 200 nautical miles around the island. The article concentrates on four of Iceland's main fisheries: shrimp, herring, capelin and cod. These four fisheries are discussed separately and in depth, presenting the beginnings and growth of the industry and detailing the development of management practices and the corresponding legislation and regulatory measures. Iceland's initial concern was to gain control over the marine resources surrounding the island, but once this was achieved, the focus of attention shifted to managing first the economic and soon also the ecological aspects of its tremendous resource. Informed mainly by indigenous expertise, Iceland's concern was to limit overfishing, manage its fisheries sustainably both from the economic and ecological points of view, and find the best ways to distribute the revenues from the marine harvest. The article looks at each of the four fisheries to clarify how the individual transferable quota (ITQ) system came into being, how initial quota holdings were allotted, and analyses the circumstances under which the ITQ system became the management tool of choice. For each fishery, the process of regulatory evolution was quite unique. At the same time, there is a common pattern to all the fisheries, which may be summarized as follows. Firstly, serious attempts to reform management practices only got underway when the fishery had collapsed or was close to collapse. Secondly, stakeholders invariably started the process of regulation by limiting access to the fishery. Thirdly, a variety of rules were implemented to allocate rights to participate in the fishery to additional entrants once membership had been closed. Finally, prior to the invention of the ITQ system, prices were used to manage fisheries in Iceland. It may be concluded that the management of fisheries by ITQs may be a historical accident, rather than the end point of a logical evolution.  相似文献   
995.
随着高校后勤社会化改革进程的不断推进,在改革的过程中出现了一些制约改革深化的因素.本文从改革的进程中发现问题并从转变管理思想、提高自主能力、建立高校后勤的企业制度几方面,讨论如何解决现阶段遇到的问题.  相似文献   
996.
城市基本生态控制线划定范围研究   总被引:2,自引:0,他引:2  
结合景观生态学原理,将城市基本生态控制线分解为基本农田控制线,河流与湿地控制线,林地控制线,山体控制线,海岸、沙滩控制线,针对每个景观生态要素控制线,通过定性、定量分析,分别提出划定依据、原则或方法。  相似文献   
997.
针对炼油厂大检修期间污水处理装置正常运行的主要经验进行总结,可为同类装置设备提供参考。  相似文献   
998.
安全生产管理平台是中国地质调查局为应对日益严峻的地质调查安全生产形势,加强地质调查安全生产监管而开发的一套软件系统,涵盖了安全管理工作的大多数内容,并具有信息处理、数据记录、文档管理、统计查询等功能。文章从系统目标、系统设计、主要功能模块等几方面分析了安全生产管理平台设计方案。建议加快安全生产管理平台研发速度,提高我国地质调查安全生产管理水平。  相似文献   
999.
1000.
对辽河流域景观结构进行分析的结果表明,2000年-2010年间,辽河流域自然景观类型面积变化不明显,结构稳定;而人工景观变化明显,居民区、交通用地等人工表面持续增加,农田面积持续减少,景观破碎化趋势明显.生态环境保护政策的实施使林地、草地、湿地等自然景观得到保护,为流域生态系统的演替提供了正向干扰;工业化进程和人口增长作为流域景观变化的主要驱动力,是人工表面增加和农田面积减少及破碎化的直接原因.  相似文献   
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