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441.
RIVPACS models for predicting the expected macroinvertebrate fauna and assessing the ecological quality of rivers 总被引:4,自引:0,他引:4
The European Union Water Framework Directive recognises the need for and value of biological monitoring. This paper reviews the modelling approach known as River Invertebrate Prediction and Classification System (RIVPACS
for assessing the ecological quality of river sites using macroinvertebrate sampling. The RIVPACS philosophy is to develop statistical relationships between the fauna and the environmental characteristics of a large set of high quality reference sites which can be used to predict the macroinvertebrate fauna to be expected at any site in the absence of pollution or other environmental stress. The observed fauna at new test sites can then be compared with their site-specific expected fauna to derive indices of ecological quality. All methodological decisions in any such model development have implications for the reliability, precision and robustness of any resulting indices for assessing the ecological quality and ecological grade (‘status’) of individual river stretches. The choice of reference sites and environmental predictor variables, the site classification and discrimination methods, the estimation of the expected fauna, and indices for comparing the agreement, or lack of it, between the observed and expected fauna, are all discussed. The indices are assessed on the reference sites and on a separate test set of 340 sites, which are subject to a wide range of types and degrees of impairment. 相似文献
442.
Catherine Meur-Férec 《Journal of Coastal Conservation》1997,3(2):121-132
In Europe, Britain was relatively early in being aware of the necessity of conserving natural coastal sites, though not as
early as The Netherlands. In the 1960s and 1970s, increasing economic and tourist pressures in Europe prompted measures geared
to the protection of other coasts in Europe. The promptness of the British reaction was a result of a sensitive public opinion
and of powerful private trusts (National Trust with Enterprise Neptune) rather than of a commitment by the Government. In
France a specific organization, in part inspired by the British principle, was set up. However, the French system is based
much more on a public authority, theConservatoire de l’Espace Littoral et des Rivages Lacustres and on legislation (Coastal Law of 1986). Although very different in the beginning, French and British conservation politics
today show many similarities, along with the similarities in the concerns of both countries. 相似文献
443.
由早中元古代中深变质岩系组成的华南加里东海盆基底及东海、南海古陆。元古代晚期,海盆在拉张环境下继续沉降,于震旦、寒武、奥陶纪期间,沉积了厚近两万米的地槽型火山-砂泥质建造,陆源碎屑主要来自东海、南海古陆,直到中生代晚期古陆才裂陷成海,始成今日的海陆分布格局。 相似文献
444.
IntroductionThenotionofsustainabledevelopmentwasproposedintheWorldConservationStrategy(IUCN,1980).Itispointedoutthattheconservationandthesustainabledevelopmentaremutuallydependentandtheyshouldbeintegrated,wheretheconservationmeansthemanagementofhuman… 相似文献
445.
In this research we explored how the concepts and approaches of ecosystem services are currently used in water management in Europe, in the application of River Basin Management Plans (RBMP) developed for the EU Water Framework Directive (WFD). Five case studies have been considered, located in the River Basin Districts of the Po river (Italy), Scotland (United Kingdom), Scheldt river (Belgium), Danube river (Romania), Sado and Mira rivers and Ribeiras do Algarve (Portugal). These cases represent different regional contexts of application of this EU water policy, with specific socio-economic drivers and environmental issues. Each case study has developed an operational framework to analyse ecosystem services in practice together with a group of local stakeholders. In each regional case, we examined how EU water policy and RBMPs are implemented, considered legal and planning instruments from the national to the local scale, and we analysed the use of ecosystem service terms and concepts in the relevant planning instruments. In parallel, we explored the view of local stakeholders and water managers on the topic, collecting their opinion on three major aspects: the usefulness of the concepts and approaches of ecosystem services for WFD river basin management plans, the risks and benefits of their use, and the knowledge needs to put the concepts into practice. The major drawback of the ecosystem service approach seems to be the challenge for practitioners of understanding new concepts and methodologies, while the major advantages are that it highlights all the hidden benefits of a water body in good health and promotes multi-functionality and sustainability in water management. The results of this study provide a picture across Europe of the current use of the concepts of ecosystem services in the RBMP and relevant insight on the opinion of local stakeholders and water managers. 相似文献
446.
中国粮食安全系统脆弱性评价及其驱动机制分析 总被引:4,自引:0,他引:4
从粮食安全系统的视角出发,运用VSD的脆弱性分析框架,从暴露性、敏感性、适应能力三个层面构建了中国粮食安全脆弱性评价指标体系,采用主成分分析方法对1991-2015年中国粮食安全脆弱性的暴露性、敏感性、适应能力进行定量分析,并探究了中国粮食安全脆弱性变化的总体趋势及其驱动因子。研究结果表明:(1)暴露性指数呈现出2阶段下降特征,年均下降0.121;敏感性指数呈现出快速上升和基本稳定的两阶段变化特征;适应能力指数则一直上升,年均提高0.117。(2)1991-2015年粮食安全系统脆弱性指数整体呈现下降趋势,表明中国粮食安水平有了明显提高;其变化过程可划分为1991-1999年、2000-2003年和2004-2015年三个阶段,第一、二阶段粮食安全水平的总体提高是基于“吃饱”水平上的提高,而第三阶段是基于“吃好”水平上的提高。(3)人均GDP、城镇化水平和城乡居民人均可支配收入四个因子共同驱动中国粮食安全脆弱性的变化,2000-2015年的第二阶段四因子对粮食安全脆弱性的驱动作用明显小于1991-1999的第一阶段,且第一驱动因子由第一阶段的农村居民人均可支配收入转变为第二阶段的人均GDP和城镇居民可支配收入。 相似文献
447.
论综合性自然资源立法 总被引:1,自引:0,他引:1
孟庆瑜 《中国人口.资源与环境》2001,11(1):41-45
综合性自然资源立法是完善我国自然资源法制的最佳方案选择。本文以正确处理自然资源开发、利用、保护和节约之间的关系为基本内容,提出了以实现自然资源的优化配置和可持续利用为目标的综合性自然资源立法的基本原则,并对综合性自然资源立法进行了具体的框架结构设计。 相似文献
448.
Graham Heaslip Alain Vaillancourt Peter Tatham Gyngyi Kovcs Deborah Blackman Marian Crowley Henry 《Disasters》2019,43(3):686-708
The continuing incidence of disasters and their associated challenges has increased the demand for humanitarian logisticians. However, there is a dearth of research on their essential competencies. This paper proposes, therefore, a humanitarian logistics competency framework (HlCF) to assist with the professional development of humanitarian logisticians. In creating the HlCF, nine competency domains containing 29 specific competencies across four levels (entry to senior management) were identified. This study makes two key contributions to the literature: (i) it extends the discussion of competency frameworks in humanitarian logistics; and (ii) it presents a framework designed to support the human resource plans and practices of aid agencies. The HlCF allows not only individual humanitarian logisticians to develop the competencies necessary for career success, but also humanitarian organisations to map their own competency frameworks to a common standard. This will, in turn, facilitate workforce mobility and support the overall concept of a certified humanitarian logistics professional. 相似文献
449.
Beidou XI Xiaoguang LI Jixi GAO Ying ZHAO Hongliang LIU Xunfeng XIA Tianxue YANG Lieyu ZHANG Xuan JIA 《Frontiers of Environmental Science & Engineering》2015,9(3):371
With the rise of environmentalism in China, great efforts have been devoted to environmental protection over the past several decades. Compared with urban environmental protection, rural environmental protection has not been attached enough importance in China due to the dual-track structure of socio-economic development. As a result, rural China is shouldering disproportionally heavy environmental burdens partly because of the differences and biases between urban and rural environmental protection seen in environmental policies, environmental rights and interests, environmental protection investment, and the environmental protection awareness of people. To eliminate the gap between rural and urban environmental protection, and achieve the goal of “balanced urban–rural environmental protection” (BUREP), government should consider mapping out proper policies and strategies. In this paper we put forward an innovative strategy of BUREP against the background of China’s urban-rural environmental protection. First, we review the current status of rural environmental protection status and its challenges compared with urban environmental protection in China. Secondly, we analyzed the main driving factors and reasons deeply, and then we put forward the BUREP strategy base on the unequal status between urban and rural environment. Finally, we proposed the framework of BUREP. This study may serve as a scientific reference regarding decision-making in coordinating urban and rural environmental protection and in constructing the new countryside of China. 相似文献
450.