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31.
In many coastal nations, community-based arrangements for marine resource management (CBRM) are promoted by government, advocated for by non-government actors, and are seen by both as one of the most promising options to achieve sustainable use and secure inshore fisheries and aquatic resources. Although there is an abundant literature on what makes CBRM effective, is it less clear how CBRM is introduced or develops as an idea in a community, and the process of how the idea leads to the adoption of a new resource management approach with supporting institutions. Here we aim to address this gap by applying an explicit process-based approach drawing on innovation history methodology by mapping and analysing the initiation and emergence of CBRM in five fishing-dependent communities in Solomon Islands. We use insights from the literatures on diffusion of innovation and transformability to define phases of the process and help guide the inductive analysis of qualitative data. We show the CBRM institutionalisation processes were non-linear, required specific strategies to move from one phase to the next, and key elements facilitated or hindered movement. Building active support for CBRM within communities depended on the types of events that happened at the beginning of the process and actions taken to sustain this. Matching CBRM to known resource management ideas or other social problems in the community, developing legitimate institutions and decision-making processes, strong continual interactions between key actors and the rest of the community (not necessarily NGO actors), and community members witnessing benefits of CBRM, all contributed to the emergence and diffusion of CBRM in the communities, and helped to overcome barriers to transformative change.  相似文献   
32.
三角洲平原上网结河的发育与聚煤作用   总被引:4,自引:4,他引:4  
陈代钊  张鹏飞 《沉积学报》1996,14(3):103-112
龙潭组上段(24#煤顶板到12#煤)是盘县地区含煤最好的层段,对该区西北部本段地层的研究表明其中发育有网结河体系。河道沉积由多层叠置的鞋带状砂体组成,湿地沉积主要由菱铁质泥质岩夹薄层板状细砂岩(决口扇沉积)和煤组成。河流的发育和聚煤作用都显示幕式性,可能主要受海平面变化的控制。网结状河道被认为是海侵期对低位下切河谷充填过程中经侧向冲裂水道并相互连通形成的;稳定、连续的厚煤层发育于河道大范围废弃后的海侵晚期,其次是高水位早期。  相似文献   
33.
Characteristics and analysis of the geomagnetic variations in regions around the Qiongzhou Strait(范国华)(姚同起)(顾左文)(朱克佳)(陈伯舫)(冯戬...  相似文献   
34.
There has been some discussion in recent times regarding whether or not substorm expansive phase activity plays any role of importance in the formation of the stormtime ring current. I explore this question using the Kp index as a proxy for substorm expansive phase activity and the Dst index as a proxy for symmetric ring current strength. I find that increases in Dst are mildly related to the strength of substorm expansive phase activity during the development of the storm main phase. More surprisingly, I find that the strength of Dst during the storm recovery phase is positively correlated with the strength of substorm expansive phase activity. This result has an important bearing on the question of how much the Dst index reflects activity other than that of the stormtime symmetric ring current strength for which it is supposed to be a proxy.  相似文献   
35.
人地耦合系统脆弱性研究进展   总被引:10,自引:1,他引:10  
当前在以人地耦合系统为中心的气候变化、生态风险和可持续管理等研究中,脆弱性理论及其评价已成为地理学及很多相关学科的研究热点,其涵义不断泛化,内容日渐扩展。不同学科背景的学者对脆弱性解释存在很大分歧,这阻碍了研究的科学化,也影响研究成果的实践意义,迫切需要一个可行的框架来系统整合其理论和实践的研究。从审视脆弱性的理论沿革出发,分析其在国内外可持续发展和全球变化领域的应用现状,总结出分歧的主要原因是对相关概念关系的不理解以及研究时空尺度和学科视角的不明确。基于对脆弱性评价的整合框架的研究现状,选取VSD模型作为统领具体的脆弱性评价的依据。VSD模型的优势在于:①有明确的定义,将脆弱性分解为暴露程度、敏感性和适应潜力3个维度;②用方面层—指标层—参数层逐级递进、细化的方式组织评价数据;③有规范评价流程的8个步骤。最后以我国典型的干旱区为例,运用VSD模型构建了示例区脆弱性评价的指标和参数。  相似文献   
36.
The transient analysis of dam–reservoir systems by employing perfectly matched layers has been investigated. In previous studies, boundary conditions of the PML region in the reservoir have been neglected. In this paper, they are incorporated completely in the formulation. Moreover, a technique is introduced to involve the effect of incident waves caused by vertical ground motions at the reservoir bottom in the analysis. Performing several numerical experiments indicates that applying boundary conditions of the PML domain and utilizing the proposed method for vertical excitation cases reduce the computational cost significantly and make the PML method a very efficient approach for the transient analysis of dam–reservoir systems.  相似文献   
37.
This article explores the suitability of Ostrom and colleagues' social-ecological systems framework (SESF) for the study of resource-dependent communities in Canada. Through a broad literature about resource-dependent communities in Canada, three main approaches are identified, named staples research, rural development, and sustainability studies. Each of these research traditions is analyzed with regards to a common set of criteria – focus, scale, methods, treatment of institutions, and treatment of environmental dimensions. Research in each category is compared and contrasted with the SESF approach, to identify areas of overlap and divergence. Results indicate that the SESF is unlikely to provide additional benefit in terms of in-depth of social analysis, however, it does provide a unique contribution in terms of its coupled approach to conceiving social and ecological systems and its ability to operationalize these relationships through structured variables.  相似文献   
38.
This paper develops a compensation algorithm based on Linear–Quadratic–Gaussian (LQG) control system design whose parameters are determined (in part) by a model of the atmosphere. The model for the atmosphere is based on the open-loop statistics of the atmosphere as observed by the wavefront sensor, and is identified from these using an auto-regressive, moving average (ARMA) model. The (LQG) control design is compared with an existing compensation algorithm for a simulation developed at ESO that represents the operation of MACAO adaptive optics system on the 8.2 m telescopes at Paranal, Chile. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
39.
Here, we report on a kinetically controlled vapour phase condensation experiment using a low-calcium Ca–Fe–SiO–H2–O2 vapour. Under these conditions of extreme disequilibrium, the condensate properties become predictable. They are amorphous solids with (predictable) deep metastable eutectic compositions. This study also shows how chemical evolution of the condensate grains will lead to chemically complex amorphous solids. The highly disordered structure of the deep metastable eutectic condensates is the very key to this predictable chemical evolution to grains with a silicate mineral composition, yet being amorphous. We compare our results with astronomical observations of dust around young stellar objects.  相似文献   
40.
Geomatics 与数字地球   总被引:8,自引:1,他引:8  
本文论述了Geomatics的内涵及特点,强调了数字地球是真实地球的数字化再现,是信息高度富集的统一体,是当代科学技术高度发展的产物,也是人类资源共享的一种概念模式.两者包含了地球系统的相关内容,并以3S等技术为支撑.知识经济时代对地理学提出了诸多问题,人类必须从全球的角度研究一系列资源环境问题,以保证全球性可持续发展战略的实施.  相似文献   
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