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951.
In isotope 137 Cs tracing studies, it is a premise to determine suitable 137 Cs reference inventory(CRI) plots and the CRI values. Owing to the heterogeneous spatial distribution of 137 Cs deposition in the ground and diverse, or even irregular, operations in sampling and testing procedures, CRI determination is usually faced with many difficulties and uncertainties. In addition, more difficulties occur in an investigation of a large-scale region because of time constraints and measurement cost limitations. In this study, traditional CRI acquiring methods were summarized first, and then a new complex scheme was established, involving seven core steps and coupling the model estimate and sample measurement. The above CRI determination methodology was implemented in the central-eastern Inner Mongolia Plateau. The case study results showed that the CRI in the dark chestnut soil sub-region, located in the east and south of Xing'an City, exhibited 2447 Bq·m–2; the CRI in the aeolian sandy soil sub-region, positioned in the south central Tongliao City and central Chifeng City, showed 2430 Bq·m–2; the CRI in the sandy chernozem soil sub-region, situated in the northwestern Chifeng City, presented 2384 Bq·m–2; and the CRI in the chestnut soil sub-region, in the southern Xilin Gol City, was 2368 Bq·m–2. The newly proposed CRI determination scheme was proved effective, and the determined CRI plots and CRI values were convincing. The methodology offered a framework for 137 Cs tracing studies in large-scale regions or long-distance transects. 相似文献
952.
With rapid urbanization and the socio-economic transformation, cultivated land protection has gradually become a major concern in China. The economic compensation plays a crucial role in promoting cultivated land protection and improving the utilization ratio of cultivated land. Farmer household's satisfaction has a great influence on the effectiveness of compensation. Therefore, households' willingness to select the economic compensation pattern for cultivated land protection has been considered and re-examined. By employing Participatory Rural Appraisal method(PRA), 3 villages and 392 households were investigated and sampled in mesa and hilly areas of Chongqing. Then a quantitative analysis framework of household livelihood hexagon has been developed to quantify the livelihood assets of different farmer households. Finally, the Gray Relation Model and Probit Regression Model have been employed to explore the coupling relationship between the household livelihood assets and their compensation pattern options. The results show that there are both qualitative and spatial heterogeneity in household livelihood assets. We found that the inequality of livelihood assets is evident for five household types. There is a spatial trend that the higher the elevation, the less livelihood assets are. In addition, their options of economic compensation pattern vary from Chengdu Pattern to Foshan Pattern due to their difference in livelihood assets and difference in location. In detail, there is a coupling relationship between household livelihood assets and their compensation pattern; negative correlation is observed between natural assets value and household pattern options, while the other livelihood assets have positive impacts on compensation pattern in varying degrees, which from the top are psychological assets, human assets, physical assets, financial assets, and social assets respectively. A conceptual compensation pattern system has been designed to meet the demands for farmer households mainly according to their shortage in livelihood assets. In addition, compensation method, compensation standard, the basis of compensation and the source of compensation funds have been proposed accordingly. 相似文献
953.
巢湖流域土地优化利用技术集成框架初探 总被引:1,自引:0,他引:1
为实现湖泊资源合理、有效、可持续开发利用,优化岸线土地利用结构和空间配置,从土地管理实际需求出发,从方法论的视角构建了土地优化利用技术研发框架,提出了以多学科模型为基础的具有标准和向导两种交互模式的插件式集成框架,阐述了巢湖流域土地优化利用决策支持系统的总体架构、插件结构和工作原理。 相似文献
954.
基于专家打分法与AHP法、多目标线性规划法获得指标体系的权重和评分值。构造了相对最大差异尺度和均衡度公式,界定了最优均衡度综合指标及其4种均衡状态、最优和非最优均衡趋向指标以及单项指标筛选标准,从而系统地改进了旅游可持续发展的评价分析方法;分析了北部湾经济区旅游可持续发展的地区差异以及影响因素,研究发现:1)北部湾经济区旅游地可持续发展能力整体不高且地区发展不平衡,南宁处于基本可持续发展阶段,其他地级市处于准备阶段;地级市之间、地区内部各要素之间的可持续发展优势差异明显。2)旅游可持续发展环境不足以及旅游业趋向过于均衡发展,促使当前与未来区域旅游发展协调处于初步可持续发展阶段,但是地区之间旅游发展环境差异小,区域旅游可持续发展潜力大。3)旅游发展规划作用明显,良好的旅游业发展现状是区域旅游发展趋向于可持续发展阶段的基础。最后从基础设施、旅游社会经济地位、旅游-经济-环境协调发展、城市旅游合作等方面提出了相应建议。 相似文献
955.
956.
山东半岛近岸海域生态系统健康综合评价 总被引:3,自引:0,他引:3
为了构建基于多指标体系的生态系统健康评价方法,作者在调研了大量国内外文献的基础上,通过实证研究和量化分析,对山东半岛近岸海域生态系统健康的现状做出了较为客观的评价。在综合考虑影响海洋生态系统健康的各种因素的基础上,构建了山东半岛近岸海域生态系统健康评价指标体系,从陆源压力、水质状态和生物响应3个方面对山东半岛近岸海域生态系统健康和环境压力进行分析。结果显示:2006年山东半岛近岸海域生态健康状况基本呈现由外海到近岸逐渐变差的态势,其中生态健康状况较差的海域主要集中在莱州湾西南部、烟台北部海域、威海的沿岸海域以及山东半岛东南部海域。 相似文献
957.
Tuong Huy Nguyen 《The Australian geographer》2014,45(3):393-406
ABSTRACTCoastal fisheries in Nha Phu lagoon, Vietnam, have encountered dramatic transformation in recent decades. Socio-economic and environmental impacts are examined through the case of fish corrals. The intensification and expansion of fish corrals has helped some households to enhance their income and livelihood assets. Technological and access-related changes associated with this transformation have also resulted in lower incomes, and even pushed poorer households into indebtedness by undermining their livelihood assets. The privatisation of common pool resources has also led to marginalisation of the poor, increasing inequality in access to natural resources and social differentiation, as not all households are able to benefit from the technological changes taking place, while access to natural resources is increasingly concentrated among the wealthier households who are driving this process. A range of measures are needed to alleviate poverty and promote more diverse sustainable livelihood development in fishing communities around the lagoon. 相似文献
958.
林乾开 《测绘与空间地理信息》2014,(12)
在简述数字县域建设所面临形势的基础上,提出了开展“数字地理空间框架市县一体化研究”的必要性,概述了开展这一研究的思路,重点介绍了研究中的关键技术、研究成果在福建省数字县域建设进程中应用的实效,并对今后的应用前景进行了展望. 相似文献
959.
960.
地理信息共享是地理信息系统研究领域的重要研究方向之一.自地理信息共享的概念提出以来,对其研究更多的是集中在技术层面,但并不能期望所有地理信息共享的障碍都能通过技术上来解决.论文从非技术视角分析了近年来国内外的几个典型地理信息共享框架/模型,对它们的优缺点做了较为详细的评述,提出了地理信息共享未来的研究方向. 相似文献