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991.
992.
Land Resource Sustainability for Urban Development: Spatial Decision Support System Prototype 总被引:1,自引:0,他引:1
Banai R 《Environmental management》2005,36(2):282-296
Land resource sustainability for urban development characterizes the problem of decision-making with multiplicity and uncertainty. A decision support system prototype aids in the assessment of incremental land development plan proposals put forth within the long-term community priority of a sustainable growth. Facilitating this assessment is the analytic hierarchy process (AHP), a multicriteria evaluation and decision support system. The decision support system incorporates multiple sustainability criteria, weighted strategically responsive to local public policy priorities and community–specific situations and values, while gauging and directing desirable future courses of development. Furthermore, the decision support system uses a GIS, which facilitates an assessment of urban form with multiple indicators of sustainability as spatial criteria thematically. The resultant land-use sustainability scores indicate, on the ratio-scale of AHP, whether or not a desirable urban form is likely in the long run, and if so, to what degree. The two alternative modes of synthesis in AHP—ideal and distributive—provide assessments of a land development plan incrementally (short-term) and city-wide pattern comprehensively (long-term), respectively. Thus, the spatial decision support system facilitates proactive and collective public policy determination of land resource for future sustainable urban development. 相似文献
993.
Land-Use and Land-Cover Change in Montane Mainland Southeast Asia 总被引:12,自引:1,他引:12
This paper summarizes land-cover and land-use change at eight sites in Thailand, Yunnan (China), Vietnam, Cambodia, and Laos
over the last 50 years. Project methodology included incorporating information collected from a combination of semiformal,
key informant, and formal household interviews with the development of spatial databases based on aerial photographs, satellite
images, topographic maps, and GPS data. Results suggest that land use (e.g. swidden cultivation) and land cover (e.g. secondary
vegetation) have remained stable and the minor amount of land-use change that has occurred has been a change from swidden
to monocultural cash crops. Results suggest that two forces will increasingly determine land-use systems in this region. First,
national land tenure policies—the nationalization of forest lands and efforts to increase control over upland resources by
central governments—will provide a push factor making it increasingly difficult for farmers to maintain their traditional
swidden land-use practices. Second, market pressures—the commercialization of subsistence resources and the substitution of
commercial crops for subsistence crops—will provide a pull factor encouraging farmers to engage in new and different forms
of commercial agriculture. These results appear to be robust as they come from eight studies conducted over the last decade.
But important questions remain in terms of what research protocols are needed, if any, when linking social science data with
remotely sensed data for understanding human-environment interactions. 相似文献
994.
基于GIS的南通市自然灾害风险区划 总被引:2,自引:1,他引:2
本文从自然致灾因子危险性和承灾体易损性2个方面选取评价指标,在南通市基础图件的基础上,通过GIS软件分析分别得到南通市自然致灾因子危险性分区图和社会经济易损性分区图.两图叠加后,生成南通市自然灾害风险区划基本单元,采用自下而上的定量区划方法,合并得到自然灾害风险区划图,最后分别论述了每个风险区的自然灾害和社会经济的特征.通过对风险区划指标和区域划分的探讨,以期为南通市防灾减灾工作提供科学依据. 相似文献
995.
996.
泥石流防治工程信息系统初探 总被引:3,自引:0,他引:3
结合泥石流防治工程的特点与地理信息系统的特征,探讨构建了泥石流防治工程信息系统的框架,定义了信息系统基本数据库的属性及其特征,实现了部分模块.构建泥石流防治工程信息系统主要是要使泥石流防治设计做到科学、高效、可行、可靠,且经济节约.同时西部大开发过程中面临大量的泥石流防治设计任务,目前专业设计人员缺乏,工作量大,该系统可为设计人员提供参考评价的工作平台,促进泥石流防治工作的高效运行. 相似文献
997.
Soil erosion is a severe problem for many developing regions that lack adequate infrastructure to combat the problem. The
authors established a first-order method for prioritizing areas to be examined and remediated using preexisting data and expert
knowledge where data are lacking. The Universal Soil Loss Equation was applied to the Rio Lempa Basin in Central America using
geographic information systems and remote sensing technologies, and the estimated erosion rates were compared with sediment
delivery ratios. Spatial analysis indicates that agriculture on very steep slopes contributes only a small fraction to the
total estimated soil erosion, whereas agriculture on gentle and moderately steep slopes contributes a large fraction of the
erosion. Although much of the basin is in El Salvador, the greatest estimated amount of erosion is from Honduras. Data quality
and availability were impaired by a lack of coordination among agencies and across countries. Several avenues for improving
the authors’ methods are described. 相似文献
998.
基于GIS的地震次生火灾蔓延范围模拟 总被引:1,自引:0,他引:1
地震次生火灾对人类的危害极大。笔者首先在对阻止火蔓延的因素进行分析以及对以往调查资料分析的基础上,确定了阻止火蔓延的距离与建筑物结构及防火类型的关系。然后,在阻止火蔓延距离的基础上,确定了地震次生火灾蔓延范围模拟的方法以及流程。最后,以汕头市为例,对地震次生火灾蔓延范围进行了模拟。通过对地震次生火灾蔓延范围的研究,为地震应急救灾提供了决策的科学依据。 相似文献
999.
基于GIS的小城镇洪灾淹没分析与应急决策系统 总被引:3,自引:0,他引:3
近年来,将GIS技术与水文模型相结合,再根据数字高程模型DEM预测、模拟显示洪水淹没区,并进行灾害评估,已成为GIS应用和水利领域一个研究热点。笔者介绍了利用GIS技术建立的小城镇洪灾淹没分析与应急决策系统的构架、数据库的建设及其实现的功能等内容。该系统解决了一系列关键技术:小城镇空间数据库的建库技术及三维可视化、洪水淹没范围的确定以及洪水淹没实时动态演示等,能够对洪水灾害及其损失进行分析预测,对洪水灾情进行快速评估,是小城镇政府部门科学地制定防洪和减灾对策,迅速有效地采取抗洪救灾措施的保障手段。该系统适合我国现有国情,有利于维护小城镇社会经济持续稳定发展,具有很强的现实意义。 相似文献
1000.
Methodological scheme for designing the monitoring of genetically modified crops at the regional scale 总被引:4,自引:0,他引:4
Graef F Züghart W Hommel B Heinrich U Stachow U Werner A 《Environmental monitoring and assessment》2005,111(1-3):1-26
According to EC regulations the deliberate release of genetically modified (GM) crops into the agro-environment needs to be
accompanied by environmental monitoring to detect potential adverse effects, e.g.unacceptable levels of gene flow from GM
to non-GM crops, or adverse effects on single species or species groups thus reducing biodiversity. There is, however, considerable
scientific and public debate on how GM crops should be monitored with sufficient accuracy, discussing questions of potential
adverse effects, agro-environmental variables or indicators to be monitored and respective detection methods; Another basic
component, the appropriate number and location of monitoring sites, is hardly considered. Currently, no consistent GM crop
monitoring approach combines these components systematically. This study focuses on and integrates spatial agro-environmental
aspects at a landscape level in order to design monitoring networks. Based on examples of environmental variables associated
with the cropping of Bt-Maize (Zea maize L.), herbicide-tolerant (HT) winter oilseed rape (Brassica napus L.), HT sugar beet
(Beta vulgaris L.), and starch-modified potato (Solanum tuberosum L.), we develop a transferable framework and assessment
scheme that comprises anticipated adverse environmental effects, variables to be measured and monitoring methods.These we
integrate with a rule-based GIS (geographic information system) analysis, applying widely available spatial area and point
information from existing environmental networks. This is used todevelop scenarios with optimised regional GM crop monitoring
networks. 相似文献