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481.
Climate change scenarios predict an increase in the frequency of heavy rainfall events in some areas. This will increase runoff and soil erosion, and reduce agricultural productivity, particularly on vulnerable mountainous agricultural lands that is already exhibiting high rates of soil erosion. Haphazard implementation of soil and water conservation (SWC) interventions on scattered fields is inefficient in reducing soil erosion. The objective of this study was to identify areas at high risk of erosion to aid the design and implementation of sustainable SWC using GIS analysis and farmers' participation approach. A 25 m digital elevation model (DEM) was used to derive layers of flow accumulation, slope steepness and land curvature, which were used to derive an erosion-risk (priority) map for the whole watershed. Boundaries of farmers' fields were mapped and verified by the community and each field was classified into high, moderate or low erosion risk. Fields with low flow accumulation (top of hill) and/or steep slope and/or convex slope were assigned high erosion risk and therefore high implementation priority. The study showed that more than 54% of the fields were classified into high erosion risk areas. Accordingly, a community-watershed plan was established, revised and approved by the community.Incentive loans to implement SWC measures were distributed to 100 farmers based on the priorities of their fields. Judged by local farmers and using 16 randomly selected fields, 90% of the targeted areas were correctly identified using the erosion risk map. After two years, the conservation measures had led to marked improvement of soil conservation. The approach is simple and easy to comprehend by the community and provides scientific basis to prioritize the implementation of SWC and to target the most degraded areas, which amplify the impact of these in reducing the vulnerability to land degradation. 相似文献
482.
自驾游以自主性、灵活性、选择性以及多样性等内在特点吸引着许多人,而它的线路设计质量直接影响自驾游者的心理满意度。通过收集、梳理河南省优秀旅游资源的空间分布、景区详情、交通道路等信息,依据旅游学中旅游行为空间模式、数学中图论和旅行商问题、地理信息系统(GIS)等科学理论,设计河南省自助游的最佳旅游线路。本研究以具有河南代表性的旅游景区为实际空间数据源,以ArcGIS系统为空间分布、交通等属性信息的可视化工具,以图论和旅行商问题为路线设计的数学基础,构建出自驾游线路设计的模式。本研究方法简单科学,为广大自驾游者规划旅游线路提供了有实际意义的参考。 相似文献
483.
从南海某油田开发方案研究出发,根据目标油田的油藏规模和储量,兼顾周边油田的区域开发需求,确定油田开发思路和钻完井机具、方式的选择方法。详细阐述油田生产处理、油气水输送、原油储存和外输的主工艺流程设计思想,系统论述油田开发主要工程设施的研究思路和方法。在经过初步工程方案筛选后,针对油田独立开发的关键设施———浮式储油生产装置(FPSO)或浮式储油装置(FSO),以改造升级旧 FPSO、旧油轮改造成 FSO 及新建 FPSO 等三个可行的开发方案为基础,确定相应的主工艺流程,从各方案技术优缺点、工期编排及工程投资估算等方面综合考虑,进行油田开发工程方案的最终选择。在此基础上,总结了南中国海油田独立开发方案的研究思路和方法,该方法对于远离陆地的油田开发方案研究具有借鉴意义。 相似文献
484.
Decision support tools in marine spatial planning: Present applications,gaps and future perspectives
《Marine Policy》2017
Evidence-based decision making is an essential process for sustainable, effective, and efficient marine spatial planning (MSP). In that sense, decision support tools (DSTs) could be considered to be the primary assistant of planners. Although there are many DSTs listed in tool databases, most of them are conceptual and not used in real MSP implementation. The main objective of this review is to: (i) characterize and analyse the present use of the DSTs in existing MSP implementation processes around the world, (ii) identify weaknesses and gaps of existing tools, and (iii) propose new functionalities both to improve their feasibility and to promote their application. In total, 34 DSTs have been identified in 28 different MSP initiatives with different levels of complexity, applicability and usage purposes. Main characteristics of the tools were transferred into a DST matrix. It was observed that limited functionality, tool stability, consideration of economic and social decision problems, ease of use, and tool costs could be considered as the main gaps of existing DSTs. Future developments are needed and should be in the direction of the specific need of marine planners and stakeholders. Results revealed that DST developments should consider both spatial and temporal dynamics of the ocean, and new tools should provide multi-functionality and integrity; meanwhile they should be easy to use and freely available. Hence, this research summarised current use, gaps, and expected development trends of DSTs and it concludes that there is still a big potential of DST developments to assist operational MSP processes. 相似文献
485.
486.
根据贵州"十二五"规划纲要对矿产资源开发利用的需求,本文对贵州重要矿产煤、磷、铝及金的资源及开发现状,结合"十二五"对矿产规划目标要求,对贵州矿产资源保障程度及存在的地质问题进行分析,提出实施贵州"十二五"规划,加强矿产资源勘查的建议。 相似文献