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851.
Vaughan H Whitelaw G Craig B Stewart C 《Environmental monitoring and assessment》2003,88(1-3):399-408
The paper describes the Ecological Monitoring and Assessment Network's (EMAN) operational and program response to certain challenges of environmental monitoring in Canada, in particular, efforts to improve the ability of the network to deliver relevant information to decision makers. In addition to its familiar roles, environmental monitoring should deliver feedback to society on environmental changes associated with development patterns, trends, processes and interventions. In order for such feedback to be effective, it must be relevant, timely, useful and accessible: all characteristics that are defined by the user, not the provider. Demand driven environmental monitoring is explored through EMAN's experiences with Canada's Biosphere Reserves, the NatureWatch Program and the Canadian Community Monitoring Network. 相似文献
852.
研究分析了柴窝堡水源地引水工程对周围地区的一系列生态环境影响,提出了若干生态环境保护对策. 相似文献
853.
芦山大地震造成了巨大的生态破坏,导致了生态系统发生退化,尤其是地形条件极其复杂的山地生态系统退化更加严重。由于地震而引发的次生灾害对于山地生态系统的影响也非常显著。生态系统及其服务的可持续性是人类社会可持续发展的决定性约束因素,震后人类赖以生存与发展的自然环境面临威胁。因此,修复生态系统,实施生态补偿是震后保护生态环境问题的迫切需要。文章分析了芦山地震对灾区生态环境及自然保护区的影响,提出了震后生态补偿的思路、重难点和对策建议,以供雅安灾后生态重建借鉴。 相似文献
854.
为调查长沙市大气中TVOC的分布特征及变化规律,研究其污染控制措施,按照相关标准和技术规范,在不同的功能区划和行政区划内合理布设12个监测点位,分季节采集样品,使用热脱附-气相色谱法进行检测,利用反距离权重插值和遥感解译等方法进行综合分析。结果表明:长沙市大气中苯与甲苯( B/T)特征比值为0.58,汽车尾气是长沙市苯系物和TVOC的主要来源;长沙市不同的工业区TVOC浓度有显著差异,工业区合理布局,增加绿化面积,可以有效的降低TVOC浓度。 相似文献
855.
全球气候变暖是人类面临的共同挑战,碳交易是为促进温室气体减排而采取的市场机制.就企业而言,碳交易直接关系到企业的生存和发展.2011年中国开展了七省市碳交易试点工作,全国碳市场将依据中国碳交易试点地区的经验设计并计划于2017年启动.本文介绍了碳交易的背景和国内外发展的新形势,总结了中国碳交易的试点状况,从而根据试点地区的碳交易模式和清洁发展机制(CDM)提出了中国企业应对全国碳交易市场的策略. 相似文献
856.
环境污染第三方治理是污染治理的新思路,是治污模式的转变和专业化分工的必然结果.杭州市在环境污染第三方治理方面尚处于摸索和自发阶段,主要在城市生活污水、生活垃圾收集处理、农村生活污水设施运维等领域有较多实践,与其它城市存在类似的发展问题:缺乏明确的政策支持、家底了解不全面、相关方责任划分不明确、第三方市场机制未建立等.通过摸清家底、明确相关方责任、建立第三方治理的准入退出机制、改善投融资环境、开展试点工作等,能初步推动杭州市环境污染第三方治理的健康发展. 相似文献
857.
Urban sprawl is a widely recognized phenomenon in many major cities worldwide and is a significant land use planning and management issue. This process has many impacts on the ecological function and structure of the landscape. In this article, we analyze the effects of urban sprawl on the ecological patterns and processes in the Montreal Metropolitan Region (MMR) between 1966 and 2010. The dispersed sprawl of low-density urban areas within the territory during this period sharply increased the fragmentation of the territory, isolating the few remaining natural spaces and decreasing their ecological connectivity and, ultimately, biodiversity. The results obtained clearly show that land-use changes that occurred in the MMR have caused profound changes in landscape properties, both structurally and functionally, and especially from 1981 to 2010. In 1966, around 45% of the land had a high or very high level of connectivity, and almost 38% in 1981. By 2010 only 6.5% of the landscape was connected and 73% of the territory possessed no or low connectivity. 相似文献
858.
以齐齐哈尔市城区声环境质量监测为依据,探讨了城区产生环境噪声污染的主要原因,分析了环境噪声污染现状,制定了相应的防治对策。 相似文献
859.
The development and use of critical loads of air pollutant deposition in the U.S. is gaining momentum, and recent research efforts in the U.S. have produced valuable data for calculating critical loads. Critical loads are used to quantify the levels of air pollutants that are expected to impact forest health, soil fertility, aquatic biota condition, and other ecosystem responses. In addition, model refinements for improving critical loads estimates, and maps for illustrating critical loads for acidification and nitrogen saturation and eutrophication resulting from excess nutrient nitrogen, have been developed at various scales. However, prior to the effort described here, no cohesive process existed to provide a national-scale critical loads database and maps as a unified product representing all U.S. ecosystems. The FOCUS (Focal Center Utility Study) Project was initiated to coordinate the development and implementation of a clear, consistent, repeatable process for calculating and mapping critical loads within the U.S. In the FOCUS Phase I Pilot Study, empirical and calculated critical loads data for the U.S. were synthesized from dozens of regional and national-scale monitoring networks, research projects and publically available databases following an approach similar to that used in Europe. The United Nations Economic Commission for Europe (UNECE), through its International Cooperative Programme on Modelling and Mapping of Critical Levels & Loads and Air Pollution Effects, Risks and Trends (ICP-M&M) collects, analyzes and maps critical loads data. Countries participating in the Convention on Long-range Transboundary Air Pollution (CLRTAP) use a Critical Loads “Focal Center” in each country to serve as the point of contact for submitting regional and national-scale critical loads data to the ICP-M&M. One of the purposes of this study was to develop a foundation for interacting with other Focal Centers by assembling critical loads data, creating a database, establishing modeling protocols, and developing infrastructure within the U.S to report and update critical loads on a national scale. Because the U.S. does not currently have an officially designated Focal Center, critical loads data were provided as an informal, unofficial submission to the Coordination Center for Effects (CCE) of the ICP-M&M in March 2011, in the interest of international cooperation and exchange of information on the effects of atmospheric deposition of pollutants on ecosystems. We envision that these data will enable U.S. scientists, land managers, and environmental policymakers to enter into a productive and meaningful dialogue within the US, and also with the international scientific community on methods for estimating, calculating, mapping, interpreting, and refining critical loads for the effects of acidification and excess nutrient nitrogen on terrestrial and aquatic ecosystems. This paper describes the process used to develop national-scale critical loads in the U.S., summarizes the FOCUS Phase I approach and database development effort, and presents some initial national-scale critical loads mapping products. 相似文献
860.