全文获取类型
收费全文 | 9731篇 |
免费 | 840篇 |
国内免费 | 2746篇 |
专业分类
安全科学 | 434篇 |
废物处理 | 247篇 |
环保管理 | 1805篇 |
综合类 | 7272篇 |
基础理论 | 1140篇 |
环境理论 | 6篇 |
污染及防治 | 874篇 |
评价与监测 | 1109篇 |
社会与环境 | 387篇 |
灾害及防治 | 43篇 |
出版年
2024年 | 56篇 |
2023年 | 206篇 |
2022年 | 329篇 |
2021年 | 412篇 |
2020年 | 414篇 |
2019年 | 380篇 |
2018年 | 304篇 |
2017年 | 411篇 |
2016年 | 414篇 |
2015年 | 512篇 |
2014年 | 528篇 |
2013年 | 700篇 |
2012年 | 710篇 |
2011年 | 786篇 |
2010年 | 613篇 |
2009年 | 605篇 |
2008年 | 483篇 |
2007年 | 677篇 |
2006年 | 686篇 |
2005年 | 485篇 |
2004年 | 463篇 |
2003年 | 493篇 |
2002年 | 414篇 |
2001年 | 385篇 |
2000年 | 359篇 |
1999年 | 259篇 |
1998年 | 199篇 |
1997年 | 175篇 |
1996年 | 163篇 |
1995年 | 120篇 |
1994年 | 113篇 |
1993年 | 78篇 |
1992年 | 71篇 |
1991年 | 58篇 |
1990年 | 42篇 |
1989年 | 18篇 |
1988年 | 15篇 |
1987年 | 28篇 |
1986年 | 15篇 |
1985年 | 11篇 |
1984年 | 6篇 |
1982年 | 15篇 |
1981年 | 17篇 |
1980年 | 13篇 |
1979年 | 10篇 |
1978年 | 17篇 |
1977年 | 5篇 |
1973年 | 8篇 |
1972年 | 9篇 |
1971年 | 11篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
931.
介绍了湖北省清江高坝洲津洋口防护区的概况,对津洋口防护区水环境污染现状进行了分析和调查研究,同时得出了防护区的主要污染为工业废水污染.计算了津洋口防护区丹水河的水环境容量,并据此提出水环境污染治理方案. 相似文献
932.
933.
根据对2006年11月20~28日乌鲁木齐市出现冷空气过境天气过程的天气形式和主要气象要素及空气污染变化情况进行的分析,结果表明:冷空气过境天气前后,诸多气象要素发生了变化,冷空气导致逆温层的破坏和降水过程使各项污染物均得到有效的清除.通过此分析可为类似天气的空气质量预报提供思路. 相似文献
934.
许多房地产项目都是在工业企业原址上进行开发建设,可能存在不同程度的土壤污染。土壤污染的评估和修复方案已成为房地产开发项目环评的重点,文中采用单因子指数法、内梅罗指数法和土壤背景值对照法对江苏某房地产用地土壤进行了环境风险评价,结果表明该地块不需要进行土壤修复和处置。 相似文献
935.
Takeshi Sasaki Atsushi Iizuka Masayuki Watanabe Teruhisa Hongo Akihiro Yamasaki 《Waste management (New York, N.Y.)》2014,34(10):1829-1835
Solid adsorbent materials, prepared from waste cement powder and concrete sludge were assessed for removal of arsenic in the form of arsenic (As(V)) from water. All the materials exhibited arsenic removal capacity when added to distilled water containing 10–700 mg/L arsenic. The arsenic removal isotherms were expressed by the Langmuir type equations, and the highest removal capacity was observed for the adsorbent prepared from concrete sludge with heat treatment at 105 °C, the maximum removal capacity being 175 mg-As(V)/g. Based on changes in arsenic and calcium ion concentrations, and solution pH, the removal mechanism for arsenic was considered to involve the precipitation of calcium arsenate, Ca3(AsO4)2. The enhanced removal of arsenic for the adsorbent prepared from concrete sludge with heat treatment was thought to reflect ion exchange by ettringite. The prepared adsorbents, derived from waste cement and concrete using simple procedures, may offer a cost effective approach for arsenic removal and clean-up of contaminated waters, especially in developing countries. 相似文献
936.
Kuang-Lung Fan 《Chemistry and Ecology》2013,29(1-2):157-166
Abstract There are three major factors affecting the coastal environment in Taiwan: tidal current, long-shore current and land subsidence. in Taiwan, most industrial areas are located on the southwestern coast. Most of the pollutants from the factories are discharged directly to the ocean, harbours or rivers. the pollutants in harbours or rivers will eventually be delivered to coastal waters. There, the tidal current is the major force dispersing the pollutants nearshore. the polluted water extends to an area about 5 km on both sides from the discharge source, and within about 3–4 km off-shore. in this study, Hsien-Da Harbour in southwestern Taiwan is cited to explain the effects of tidal current on the coastal environment. the long-shore current induced by breaking waves is the major force shaping the coastal morphology. Along the western coast of Taiwan, the long-shore current mainly flows northward along the southern section, and southward along the northern section. in the last one hundred years, in general, the coast has been eroded along the northern and southern sections of western coast, and some reclaimed lands were formed in the middle section. Recently, erosion in some coastal zones is quite serious because of excess groundwater extraction, especially along the southwestern coast. Groundwater extraction might also induce land subsidence. There are some areas near the coast which suffer serious land subsidence problems. 相似文献
937.
J. M. Bewers 《Chemistry and Ecology》2013,29(1-2):9-23
Abstract Differences between the scientific and environmental policy communities regarding marine environmental protection strategies are discussed in the context of the nature and extent of scientific influence on marine environmental policy. Public perceptions of the nature and severity of marine pollution frequently differ from scientific assessments. the thesis of this paper is that the increasing influence of public perception on marine environmental protection policy is leading to the adoption of simplistic and unnecessarily extreme approaches to marine pollution prevention and to a reduced reliance on science. This trend is illustrated by some recent international developments and some suggestions are made towards enhancing the influence of science on marine protection policy. 相似文献
938.
环境保护同经济建设和社会发展相协调,是我国环境保护的基本原则。本文从环境保护与经济发展的相互关系出发,比较实际地估计了我省各种污染排放物及造成的经济损失,探讨了环保治理资金社会投入的比例问题。 相似文献
939.
Keith C. Knapp Ariel Dinar Phyllis Nash 《Journal of the American Water Resources Association》1990,26(2):289-298
ABSTRACT: Agricultural drainage water is a major source of environmental pollution in many areas. This paper reviews the literature on the economics of nonpoint-source pollution and applies it to the regulation of agricultural drainage water. Four types of regulatory policies are considered. The empirical analysis is carried out for cotton production in the San Joaquin Valley of California. Variable inputs are the quantity of water applied and the type of irrigation system. All four policies can achieve economic efficiency under the conditions assumed here, but the policies differ in terms of the distributional impacts and administrative requirements. 相似文献
940.
Marc O. Ribaudo C. Edwin Young 《Journal of the American Water Resources Association》1989,25(1):71-78
ABSTRACT: A framework for estimating the water quality benefits from soil erosion was developed. The framework is based on the linkages between soil erosion and offsite damages. The linkages are: erosion on the field, movement of eroded materials to waterways, impact of discharged material on water quality parameters, impact of water quality changes on ability of water to provide economic services, and the economic value of the changes in water use. These linkages need to be modeled in order to estimate the water quality benefits from reductions in soil erosion. Methods for modeling each link on a geographic level, which enables the analyses of national soil conservation, were examined. Areas where data or models were found to be lacking include transport of sediment and nutrients to water systems, impact of discharged materials on water quality parameters, and impact of water quality on ability of water to provide economic services. An economic evaluation of 1983 soil conservation programs was presented as an example of how the framework could be used. A number of simplifying assumptions were made to represent links that could not be modeled with available data. 相似文献