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101.
Systematic planning for conservation is highly regarded but relies on spatially explicit data that are lacking in many areas of conservation concern. The decision support tool Marxan is applied to a reef system in the central Philippines where 30 marine protected areas (MPAs) have been established in communities without much use of biophysical data. The intent was to explore how Marxan might assist with the legally required expansion to protect 15% of marine waters, and how existing MPAs might affect that process. Results show that biophysical information alone did not provide much guidance in identifying patterns of conservation importance in areas where the data are poor. Socioeconomic data were needed to distinguish among possible areas for protection; but here, as elsewhere in marine environments, the availability of such data was very limited. In the final analysis, local knowledge and integrated understanding of socioeconomic realities may offer the best spatially explicit information. The 30 existing MPAs, which encompassed a small proportion of the reef system, did not limit future options in developing a suite of MPAs on a broader scale. Rather, they appeared to generate the support for MPAs that is obligatory for any larger zoning effort. In summary, establishing MPAs based on community-driven criteria has biological and social value, but efforts should be made to collect ecological and socioeconomic data to guide the continued creation of MPAs.  相似文献   
102.
Southern California's marine areas are heavily contaminated with dichloro-diphenyl-trichloroethane (DDT) and polychlorinated-biphenyls (PCBs), and fish consumption advisories (FCAs) have been issued throughout the region. Between 2002 and 2003, the Montrose Angler Survey, a large-scale survey of subsistence anglers, was developed and implemented on site in Orange and Los Angeles counties. This survey was intended to assist natural resource trustees in the development of restoration programs that will address injuries to natural resources and restore lost economic services for anglers, but the data were never fully analyzed. The trustees have shown a clear preference for ecological restoration programs that may take years to improve fishing services. In contrast, this analysis, which includes a random-parameter fishing site choice model, demonstrates that simple, inexpensive programs such as better signage to warn of FCAs and transportation to clean sites have the potential to yield substantial benefits quickly. This paper also focuses on how different ethnic minority groups are affected by FCAs, and determines how best to communicate risk information and change fishing behavior through outreach programs.  相似文献   
103.
Large intensity and diversity of human activities result in an increase in complexity in the utilization of space. This paper describes the fisheries and a method to map fishing efforts and catches of different fleets by combining vessel monitoring system (VMS) data and logbook data. The method makes it possible to explore the spatial and temporal variability of fishing and the potential impacts of proposed management measures on the fisheries. The method is proposed to be used in the development of management plans for marine protected areas such as Natura 2000 sites, designated to protect vulnerable habitats and species.  相似文献   
104.
The quantity of coastline retreat resulting from storm erosion is one of the most important phenomena that needs to be accurately quantified to facilitate effective coastal management strategies. Historically, the volume of storm erosion (and coastline retreat) accommodated for coastal planning decisions has been directly linked to the storm (usually defined by considering wave height and duration only) with a certain pre-defined return period, known as a Synthetic Design Storm (SDS) (e.g. 1 in 100 year storm). The SDS method of estimating storm erosion volumes for coastal planning thus assumes that, for example, the 1 in 100 year storm event also results in a 1 in 100 year erosion event. This communication discusses the physical reality of this assumption and demonstrates the improved performance of a new method, based on Joint Probability Distributions (JPD) for estimating storm erosion volumes proposed by Callaghan et al. [Callaghan, D.P., Nielsen, P., Short, A.D. and Ranasinghe, R., 2008. Statistical simulation of wave climate and extreme beach erosion. Coastal Engineering, 55(5): 375–390] using one of the world's longest beach profile surveys from Sydney, Australia.  相似文献   
105.
106.
1IN T R O D U C T IO N Since the20th century, ecosystem and even biosphere has been facedwith threat sunder theimpactsofclimate and humankind together(E RICH and ULRIKE , 2002 ; G LADE ,2003 ;O LGERTS etal.,2005 ).Land isan im- portantpartof natureecosyst…  相似文献   
107.
针对整个城市规划过程的参与者对规划数据的不同种类、不同层次认知需求,本文利用本体思想对包括GIS数据、规划文档、规划图件等多源异构的规划数据进行关系重构,设计本体模型要素的数据语义关系,定义数据间的关联关系,实现基于本体方法的规划领域语义表达算法,方便了各类规划参与者对规划方案认识的交流:同时根据用户特征分类,进行本体关系的逻辑推理,过滤冗余信息,进行多源异构规划数据的可视化。  相似文献   
108.
开展"多规合一"是推进生态文明建设、新型城镇化建设,落实供给侧改革的必然要求。本文以地理信息技术为基础,以土地利用规划为底盘,统一城乡规划、环保规划、农业发展规划等的空间基础;以经济社会发展规划为目标协调各规划,划定永久基本农田保护红线、生态保护红线、城市开发边界,实施严格的空间管控。最后,以常州市新北区为试验区,分析各规划的差异并落实重点项目,引导国土空间有序开发,优化资源空间配置,形成国土空间开发规划"一张图"。  相似文献   
109.
城镇-农业-生态空间划定(简称"三区"划定)是国土空间规划的核心内容,对于科学合理地规划、利用有限的国土资源具有重要的意义。已有研究主要根据区域内土地利用与社会经济发展现状构建指标体系进行"三区"划定,较少将未来土地利用变化纳入"三区"划定过程中,使得划定结果在指导实践过程中缺乏前瞻性。针对这一问题,本文提出一种基于土地利用情景模拟,结合指标体系评价与决策树特征挖掘的"三区"划定方法,并以武汉市2015年土地利用现状为基础,在土地利用变化情景模拟的基础上进行"三区"划定。通过对比,验证了本文提出方法的合理性。研究发现:①不同情景下的"三区"空间在规模、空间分布上具有明显差异,将未来土地利用变化纳入"三区"划定过程中确有必要;②不同土地利用情景下"三区"空间的差异主要出现在三类空间的交界区域,这些区域是国土空间规划应该关注的重点区域。  相似文献   
110.
标准农田规划空间决策支持模型的研究与实现   总被引:1,自引:0,他引:1  
在中国工业化与城市化进程加速的背景下,部分地区耕地的质与量难以得到保障,因此迫切需要在平衡粮食安全与经济社会增长的基础上对其做出科学规划,而空间决策支持模型的建立有助于该规划的编制。基于对标准农田规划过程的分析,将模型的概念框架分解为以下三个步骤:①构建标准农田资源评价模型:利用群体层次分析法和土地适应性评价模型评估标准农田资源;②构建标准农田规划备选方案生成模型:采用0 ̄1整数规划模型生成若干标准农田规划备选方案;③构建标准农田最优规划方案决策模型,采用非确定型决策模型辅助评价选取最优规划方案。文章对概念模型的规范化过程进行详细探讨,最后以浙江省桐庐县石阜镇为实验区,对模型进行实现和初步验证。  相似文献   
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