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641.
以地理信息系统(GIS)为技术支持,以生态系统组成和空间结构为指标,对吉林省东部的生态建设分区进行研究。借助AreView分析工具,从吉林省2000年的1:100000土地利用数字化地图中,提取东部山区土地利用数据,进行生态系统的结构研究,并在此基础上划分出东部山区生态系统的生态经济类型,为土地资源的有效利用和生产力的合理布局提供决策支持。 相似文献
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Brett G. Dickson Christine M. Albano Ranjan Anantharaman Paul Beier Joe Fargione Tabitha A. Graves Miranda E. Gray Kimberly R. Hall Josh J. Lawler Paul B. Leonard Caitlin E. Littlefield Meredith L. McClure John Novembre Carrie A. Schloss Nathan H. Schumaker Viral B. Shah David M. Theobald 《Conservation biology》2019,33(2):239-249
Conservation practitioners have long recognized ecological connectivity as a global priority for preserving biodiversity and ecosystem function. In the early years of conservation science, ecologists extended principles of island biogeography to assess connectivity based on source patch proximity and other metrics derived from binary maps of habitat. From 2006 to 2008, the late Brad McRae introduced circuit theory as an alternative approach to model gene flow and the dispersal or movement routes of organisms. He posited concepts and metrics from electrical circuit theory as a robust way to quantify movement across multiple possible paths in a landscape, not just a single least-cost path or corridor. Circuit theory offers many theoretical, conceptual, and practical linkages to conservation science. We reviewed 459 recent studies citing circuit theory or the open-source software Circuitscape. We focused on applications of circuit theory to the science and practice of connectivity conservation, including topics in landscape and population genetics, movement and dispersal paths of organisms, anthropogenic barriers to connectivity, fire behavior, water flow, and ecosystem services. Circuit theory is likely to have an effect on conservation science and practitioners through improved insights into landscape dynamics, animal movement, and habitat-use studies and through the development of new software tools for data analysis and visualization. The influence of circuit theory on conservation comes from the theoretical basis and elegance of the approach and the powerful collaborations and active user community that have emerged. Circuit theory provides a springboard for ecological understanding and will remain an important conservation tool for researchers and practitioners around the globe. 相似文献
644.
基于卫星影像解译的华中地区自然景观分类与制图 总被引:2,自引:0,他引:2
依据1:150万中国卫星影像图并参考有关专题图件资料,通过景观组成要素分析法和专题图件对比分析法,拟定了华中地区自然景观分类系统并编制该区1:150万自然景观类型解译图,抽样检验表明,平均判对率达90.5%。 相似文献
645.
K. Tybirk H. F. Alrøe P. Frederiksen 《Journal of Agricultural and Environmental Ethics》2004,17(3):249-274
Nature quality in relation to farming is a complex field. It involves different traditions and interests, different views of what nature is, and different ways of valuing nature. Furthermore there is a general lack of empirical data on many aspects of nature quality in the farmed landscape. In this paper we discuss nature quality from the perspective of organic farming, which has its own values and goals in relation to nature – the Ecologist View of Nature. This is in contrast to the Culturist View characteristic of much conventional agriculture and the Naturalist View characteristic of the traditional biological approach to nature quality. This threefold distinction forms a framework for exploration of nature quality criteria in the farmed landscape. The traditional work on nature quality has mainly focused on biological interests based on a Naturalist View of Nature. In this paper we will explore how criteria for nature quality based on the Ecologist View can be developed and thereby feed into the ongoing discussion of the development of the organic farming practices. We suggest additional criteria for nature quality based on an Ecologist View of Nature: biodiversity, habitat diversity, extent and structure, functional integrity of habitats and agro-ecosystems, landscape integrity, accessibility, and experientiality. The larger set of Naturalist and Ecologist criteria can provide a wider and more balanced basis for developing nature quality indicators that are relevant in the farmed landscapes. This broader approach to nature quality is also expected to benefit the general societal discussions and decisions on farming and nature. 相似文献
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The degradation of water quality in many groundwaters of Europe is a major source of concern. Rises in turbidity and nitrate concentrations represent present or potential threats for the quality of drinking water in rural areas. They are for the most part a consequence of agricultural intensification which has considerably affected land cover and land use in recent decades. In our case-study (a karstic catchment) the mechanisms which explain changes in water quality, as far as turbidity and nitrate are concerned, result from a strong continuity between surface and underground waters. The karstic system of the Brionne Basin can be considered as both the focus of rapid horizontal flows (runoff, a rapid process in which rainwater reaches the spring directly through sinkholes) and slow vertical flows (leaching, in which rainwater filters through the soil to the spring). A hierarchical approach to the water pollution problem of the basin suggests that turbidity or nitrate concentrations peak during heavy rain episodes and are short-term events. In terms of management, this implies that the solution to water pollution caused by such events is also short-term and can therefore be addressed at a local scale. The rise of nitrate concentrations during the past twenty years is the main concern. The solution can only be found at a global scale (all the catchment area must be taken in account: land plots and their spatial configuration), and by taking a long-term approach. 相似文献
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649.
依靠发展生态旅游业解决我国自然保护区事业发展存在的问题 总被引:1,自引:0,他引:1
朱凌 《中国环境管理干部学院学报》2005,15(1):32-34
自然保护区管理是环境管理的一个重要方面,也是我国可持续发展的一项重要事业.虽然我国自然保护区事业近些年发展速度很快,但是在自然保护区建设和管理中存在很多困难和问题,本文分析了这些问题所在之后,提出依靠在自然保护区内发展生态旅游业来解决,旨在促进我国自然保护区事业向着可持续的方向发展. 相似文献
650.
本文运用生态经济学、系统工程学和规划论的观点,对如何编制县级生态农业建设规划进行了探讨。提出编制规划的基本思路和应遵循的主要原则,并从现状评价、潜力分析、规划目标、规划方案、重点项目、效益预测和主要措施等方面对规划应包括的主要内容和具体要求进行了系统的阐述。 相似文献