全文获取类型
收费全文 | 10365篇 |
免费 | 835篇 |
国内免费 | 2512篇 |
专业分类
安全科学 | 517篇 |
废物处理 | 337篇 |
环保管理 | 2357篇 |
综合类 | 6037篇 |
基础理论 | 1338篇 |
环境理论 | 6篇 |
污染及防治 | 928篇 |
评价与监测 | 281篇 |
社会与环境 | 1733篇 |
灾害及防治 | 178篇 |
出版年
2024年 | 66篇 |
2023年 | 206篇 |
2022年 | 372篇 |
2021年 | 366篇 |
2020年 | 328篇 |
2019年 | 339篇 |
2018年 | 336篇 |
2017年 | 417篇 |
2016年 | 477篇 |
2015年 | 469篇 |
2014年 | 530篇 |
2013年 | 970篇 |
2012年 | 894篇 |
2011年 | 942篇 |
2010年 | 628篇 |
2009年 | 571篇 |
2008年 | 496篇 |
2007年 | 680篇 |
2006年 | 703篇 |
2005年 | 502篇 |
2004年 | 456篇 |
2003年 | 442篇 |
2002年 | 403篇 |
2001年 | 346篇 |
2000年 | 359篇 |
1999年 | 282篇 |
1998年 | 212篇 |
1997年 | 181篇 |
1996年 | 147篇 |
1995年 | 111篇 |
1994年 | 105篇 |
1993年 | 93篇 |
1992年 | 66篇 |
1991年 | 30篇 |
1990年 | 31篇 |
1989年 | 11篇 |
1988年 | 9篇 |
1987年 | 15篇 |
1986年 | 15篇 |
1985年 | 5篇 |
1984年 | 5篇 |
1983年 | 5篇 |
1982年 | 14篇 |
1981年 | 10篇 |
1980年 | 11篇 |
1979年 | 14篇 |
1978年 | 9篇 |
1977年 | 5篇 |
1973年 | 5篇 |
1971年 | 10篇 |
排序方式: 共有10000条查询结果,搜索用时 140 毫秒
341.
Fred A. Otchere Marcello M. Veiga Jennifer J. Hinton Renato A. Farias Robert Hamaguchi 《Natural resources forum》2004,28(3):216-223
The legacy of mining activities has typically been land ‘returned to wildlife’, or, at some sites, degraded to such an extent that it is unsuitable for any alternate use. Progress towards sustainability is made when value is added in terms of the ecological, social and economic well‐being of the community. In keeping with the principles of sustainable development, the innovative use of flooded open pits and tailings impoundments as commercial, recreational or ornamental fish farms should be considered in some locations, as it could make a significant contribution to the social equity, economic vitality and environmental integrity of mining communities. This article highlights the growing significance of aquaculture and explores the benefits and barriers to transforming flooded pits and impoundments into aquaculture operations. Among other benefits, aquaculture may provide a much‐needed source of revenue, employment and, in some cases, food to communities impacted by mine closure. Further, aquaculture in a controlled closed environment may be more acceptable to critics of fish farming who are concerned about fish escapes and viral transmissions to wild populations. Despite the potential benefits, aquaculture in flooded pits and impoundments is not without its complications — it requires a site‐specific design approach that must consider issues ranging from metals uptake by fish, to the long‐term viability of the aquatic system as fish habitat, to the overall contribution of aquaculture to sustainability. 相似文献
342.
Brazil produces approximately 242,000 t of waste per day, 76% of it being dumped outdoors and only 0.9% recycled, including composting, which is an alternative still little known in Brazil. In search of a better destination for residues produced by domestic activities, composting stands as a feasible alternative. Organic compost from waste may be used for various purposes, among which are soil recovery, commercial production, pastures, lawns and reforestry and agriculture. However, the quality of the compost determines the growth and the development of plants. The effect of compost made from urban waste on corn plant (Zea mays L.) growth was investigated. Two types of compost were used: the selected compost (SC), produced from organic waste selectively collected; and the non-selected compost (NSC), taken from a 15-year-old cell from the Canabrava land-fill, located in Salvador, Bahia, Brazil (altitude 51 m, 12°22′–13°08′S, 38°08′–38°47′W). Corn was seeded in polyethylene pots, with soil-compost mixing substrate in the proportion of 0, 15, 30, 45 and 60 t ha−1 equivalent doses. Chemical analyses of the compost and growth properties of the plant like chlorophyll content; height and stem diameter; aerial and radicular dry biomasses, were used to evaluate compost quality. Plants cultivated with SC presented a superior gain, being of 52.5% in stem diameter, 71.1 and 81.2% in root and stem biomasses, respectively. Chlorophyl content alterations were observed in plants from treatments using 30 t compost ha−1 dose onwards. Conventional and multivariate statistical methods were used to evaluate these results. The beneficial action of organic compost in plant growth was confirmed with this research. 相似文献
343.
中国湿地现状综述 总被引:9,自引:0,他引:9
刘军 《中国环境管理干部学院学报》2004,14(2):64-67
湿地是重要的自然资源,对人类生存起着重要作用。本文综述了湿地的含义、功能与 价值、中国湿地的特点与现状,以促进中国湿地的可持续发展与利用。 相似文献
344.
简要介绍了中国的能源供求现状,指出中国能源的两大特征:①煤炭消费为主;②人均消费低、能源利用率低。笔者强调,中国能源对外依存增大,已成为能源输入国;提出逐步调整以煤为主的能源结构,实现能源替代,构建优质化、多元化的能源结构的策略;着重从5个方面进行调整———重点解决石油供不应求的能源结构性矛盾、加强煤炭资源的清洁和优质开发利用、发展以利用洁净煤技术为基础的电力工业、提高核电的比例、加强新能源和可再生能源的开发利用,确保我国能源的安全稳定供应和可持续发展。 相似文献
345.
346.
347.
348.
349.
通过对区位优势不明显,社会、经济和文化落后,但资源丰富的典型的欠发达县域凤庆县的实证研究,从思想观念、所有制结构、产业结构、基础建设、社会文化和经济,以及生态环境和农业基础等方面剖析了凤庆县经济不可持续发展的主要症结及原因,提出了该县经济可持续发展的总体思路,并作了对策探讨. 相似文献
350.
从民族生态学的角度分析哈尼梯田民族生态学实践,阐述了哈尼梯田民族生态系统可持续发展的限制性因素.从认识论、方法论和技术三个层面构建了哈尼梯田民族生态系统的可持续发展模式,旨在为民族生态系统的可持续发展和新的文化生态伦理观的确立提供有益借鉴. 相似文献