全文获取类型
收费全文 | 10198篇 |
免费 | 1010篇 |
国内免费 | 1561篇 |
专业分类
安全科学 | 675篇 |
废物处理 | 78篇 |
环保管理 | 1757篇 |
综合类 | 6138篇 |
基础理论 | 1571篇 |
环境理论 | 14篇 |
污染及防治 | 432篇 |
评价与监测 | 590篇 |
社会与环境 | 1133篇 |
灾害及防治 | 381篇 |
出版年
2024年 | 80篇 |
2023年 | 222篇 |
2022年 | 344篇 |
2021年 | 394篇 |
2020年 | 415篇 |
2019年 | 293篇 |
2018年 | 280篇 |
2017年 | 445篇 |
2016年 | 476篇 |
2015年 | 457篇 |
2014年 | 508篇 |
2013年 | 660篇 |
2012年 | 713篇 |
2011年 | 767篇 |
2010年 | 624篇 |
2009年 | 549篇 |
2008年 | 446篇 |
2007年 | 698篇 |
2006年 | 695篇 |
2005年 | 568篇 |
2004年 | 512篇 |
2003年 | 428篇 |
2002年 | 399篇 |
2001年 | 302篇 |
2000年 | 317篇 |
1999年 | 249篇 |
1998年 | 144篇 |
1997年 | 167篇 |
1996年 | 114篇 |
1995年 | 122篇 |
1994年 | 97篇 |
1993年 | 81篇 |
1992年 | 54篇 |
1991年 | 46篇 |
1990年 | 36篇 |
1989年 | 11篇 |
1988年 | 16篇 |
1987年 | 2篇 |
1986年 | 4篇 |
1985年 | 2篇 |
1984年 | 3篇 |
1983年 | 5篇 |
1981年 | 4篇 |
1979年 | 4篇 |
1977年 | 2篇 |
1976年 | 2篇 |
1975年 | 1篇 |
1974年 | 3篇 |
1971年 | 4篇 |
1970年 | 1篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
María L. Pignata Martha S. Cañas Hebe A. Carreras Liliana Orellana 《Environmental management》1997,21(5):793-801
Ligustrum lucidum Ait. f. tricolor (Rehd.) Rehd. in relation to atmospheric pollutants in Córdoba city, Argentina. The study area receives
regional pollutants and was categorized taking into account traffic level, industrial density, type of industry, location
of the sample point in relation to the street corner, treeless condition, and topographic level. Dried weight/fresh weight
ratio (DW/FW) and specific leaf area (SLA) were calculated, and concentrations of chlorophylls, carotenoids, total sulfur,
soluble proteins, malondialdehyde (MDA), and hydroperoxy conjugated dienes (HPCD) were determined in leaf samples. Sulfur
content correlates positively with traffic density and SLA correlates negatively with some combinations of the categorical
variables; MDA correlates positively with topographic level and total protein concentration correlates negatively with treeless
condition. On the basis of our results, traffic, location of trees, type of industry, situation of a tree with respect to
others, and topographic level are the environmental variables to bear in mind when selecting analogous sampling points in
a passive monitoring program. An approximation to predict tree injury may be obtained by measuring DW/FW ratio, proteins,
pigments, HPCD, and MDA as they are responsible for the major variability of data. 相似文献
2.
Abstract: Broadly conceived and considered in its many usages, sustainability has grave defects as a planning goal, particularly when used by conservationists: it confuses means and ends; it is vague about what is being sustained and who or what is doing the sustaining; it is uninspiring; it is little more than Pinchot-era conservation (and thus ignores the many lessons learned since then); it need not be linked to land, to the land's functioning, or to any ecological science; it need not include a moral component; it is consistent with the view of humans as all-powerful manipulators of the planet; and, in general, it is such a malleable term that its popularity provides only a facade of consensus. When sustainability is defined broadly to include the full range of economic and social aspirations, it poses the particular risk that ecological and biodiversity concerns will be cast aside in favor of more pressing human wants. Given these many defects, the conservation movement should discard the term in favor of a more alluring goal, attentive to nature and its ecological functioning. A sound goal would incorporate and distill the considerable ecological and moral wisdom accumulated since Pinchot's day while giving conservationists the rhetorical tools needed to defend the land against competing pressures. In our view, conservation would be well served by an updated variant of "land health," Aldo Leopold's ecologically grounded goal from the 1940s. Land health as an independent understanding should set the essential terms of how we live and enjoy the earth, providing the framework within which we pursue our many social and economic aims. 相似文献
3.
4.
根据自然地理、海洋动力、生物等特征!本文研究受大河作用的大丰潮滩地貌、沉积过程,讨论老黄河和长江对该潮滩发育的影响和潮滩生物群落空间分布及演变规律。本文评价了大丰潮滩开发利用现状,分析了它们的经济效益和环境效益,提出把目前受到强烈改造、过度利用的模式改变为顺应潮滩自然演变、有步骤合理开发利用潮滩的模式。 相似文献
5.
小城镇的生态环境保护 总被引:1,自引:0,他引:1
在城镇化不断发展的进程中,小城镇的生态环境日益恶化。分析了小城镇生态环境存在的问题,提出了应采取的生态环境保护规划与对策。 相似文献
6.
采用自然吸入的暴露方法,通过分析肺灌洗液成分及脾脏淋巴细胞的转化功能,观察碳素厂冷压车间空气对大鼠肺损伤及免疫功能的影响,结果表明,在自然吸入染毒期间,引起大鼠肺灌洗液中乳酸氢酶、酸性磷酸酶和唾液含量或高,肺巨噬细胞及其Fc受体数降低,并且还引起脾脏淋巴细胞的转化能力下降。 相似文献
7.
8.
The lessons of history indicate that mismanagement of natural resources and the environment often leads to potentially adverse consequences.The increasing interest in economic development,particularly in the developing countries of the world coupled with increasing population pressures and the globalization of economic activity is placing noticeable stresses on the ultimate sustainability of both human and environmental systems.Sustainable development is not a new concept.It has been an area of concern for different elements of society for some time.Yet efforts to understand the implications of sustainable development have not,until recently,been formalized.We have focused singularly on economic development and environmental quality as if they were mutually exclusive.This paper focuses on the concept of concurrency as both a conceptual framework and practicable method of understanding and implementing the ecology and economy of sustainability. 相似文献
9.
应用新的资源价值观念与环境经济学中MOC框架及其它理论,给出了建材资源的生态环境补偿费的定义与确定方法,建立了相应的理论模型。在此基础上,根据不同地区的经济发展水平与环境现状等实现情况,用认可系数对计算的补偿费进行修正。 相似文献
10.