全文获取类型
收费全文 | 6507篇 |
免费 | 531篇 |
国内免费 | 1786篇 |
专业分类
安全科学 | 158篇 |
废物处理 | 23篇 |
环保管理 | 983篇 |
综合类 | 4668篇 |
基础理论 | 715篇 |
污染及防治 | 555篇 |
评价与监测 | 712篇 |
社会与环境 | 824篇 |
灾害及防治 | 186篇 |
出版年
2024年 | 35篇 |
2023年 | 137篇 |
2022年 | 273篇 |
2021年 | 275篇 |
2020年 | 297篇 |
2019年 | 264篇 |
2018年 | 242篇 |
2017年 | 288篇 |
2016年 | 364篇 |
2015年 | 437篇 |
2014年 | 338篇 |
2013年 | 475篇 |
2012年 | 492篇 |
2011年 | 564篇 |
2010年 | 358篇 |
2009年 | 394篇 |
2008年 | 376篇 |
2007年 | 417篇 |
2006年 | 409篇 |
2005年 | 327篇 |
2004年 | 235篇 |
2003年 | 243篇 |
2002年 | 216篇 |
2001年 | 174篇 |
2000年 | 179篇 |
1999年 | 179篇 |
1998年 | 133篇 |
1997年 | 129篇 |
1996年 | 84篇 |
1995年 | 86篇 |
1994年 | 79篇 |
1993年 | 66篇 |
1992年 | 38篇 |
1991年 | 29篇 |
1990年 | 21篇 |
1989年 | 9篇 |
1988年 | 16篇 |
1987年 | 11篇 |
1986年 | 14篇 |
1985年 | 10篇 |
1984年 | 7篇 |
1983年 | 7篇 |
1982年 | 13篇 |
1981年 | 10篇 |
1980年 | 15篇 |
1979年 | 15篇 |
1978年 | 10篇 |
1977年 | 6篇 |
1973年 | 7篇 |
1971年 | 7篇 |
排序方式: 共有8824条查询结果,搜索用时 172 毫秒
71.
唐山市空气中SO2与TSP污染状况分析 总被引:1,自引:0,他引:1
分析了唐山市从1988年至1992年大气中SO2和TSP的污染状况和变化规律,取得对该市环境管理的科学依据。 相似文献
72.
80年代初和80年代末对黄河宁夏段的经济鱼类的含汞水平进行了监测,结果表明:这段河道的汞污染对经济鱼类的影响起来越严重,超标率由32%~38%发展到100%,1988年鲶鱼含汞达2.47mg/kg,超标7.2倍. 相似文献
73.
Diazinon contamination of California's rivers has resulted in placing several rivers on the federal Clean Water Act § 303d list of impaired waterways. Impaired water body listing requiresthe development of Total Maximum Daily Loads (TMDL). Previous studies identified stormwater related diazinon pulses in California rivers. This study was conducted to monitor diazinonconcentrations in the Sacramento River watershed after rainfallevents, to ascertain whether pulses could be identified and, ifconcentrations of concern were observed, to estimate loadings anddetermine geographic origins of the insecticide. TMDL developmentrequires knowledge of contaminant sources, loadings, and geographic origins. Flow and diazinon concentrations peaked in the Sacramento River at Sacramento after the three largest stormsduring January and February 1994. Diazinon concentrations peakedconsequent to each of three storms. Diazinon concentrationsmeasured in the Sacramento River at Sacramento exceeded theCalifornia Department of Fish and Game acute and chroniccriteria for protection of aquatic life during January andFebruary for nine and nineteen days, respectively. Multipleexceedances were observed throughout the watershed. Diazinon loading and geographic origin differed with each of the three storms. The design of this study provides a useful template for others attempting to identify loadings and sources of contaminants in surface waters and to rectify aquatic ecosystemcontamination from various land use practices. 相似文献
74.
Kelsey RH Scott GI Porter DE Thompson B Webster L 《Environmental monitoring and assessment》2003,81(1-3):337-348
Multiple Antibiotic Resistance (MAR) analysis and regression modeling techniques were used to identify surface water areas impacted by fecal pollution from human sources, and to determine the effects of land use on fecal pollution in Murrells Inlet, a small, urbanized, high-salinity estuary located between Myrtle Beach and Georgetown, South Carolina. MAR analysis was performed to identify areas in the estuary that are impacted by human-source fecal pollution. Additionally, regression analysis was performed to determine if an association exists between land use and fecal coliform densities over the ten-year period from 1989 to 1998. Land-use variables were derived using Geographic Information System (GIS) techniques and were used in the regression analysis.MAR analyses were conducted by comparing the frequency and patterns of antibiotic resistance found in Escherichia coli isolates derived from surface water samples and from sewage sources in the Murrells Inlet sewage collection system. The MAR results suggest that the majority of the fecal pollution detected in the Murrells Inlet estuary may be from non-human sources, including fecal coliforms isolated from areas in close proximity to high densities of active septic tanks.A MAR Index, which measures the frequency of antibiotic resistance, was calculated for each of twenty-three water samples and nine sewage samples. The antibiotic resistance pattern comparisons were performed using cluster analysis. Although the MAR indices indicated that several surface water sites had potential human-source contamination, the cluster analysis suggests that only one sampling site had MAR patterns that were similar to those found in the sewage samples. This site was in close proximity to several large pleasure boats as well as a sewage collection system lift station, but was not near areas with active septic tanks. The results of the regression analysis also suggest that sewage sources and rainfall runoff from urbanized areas may contribute to fecal pollution in the estuary. 相似文献
75.
环境监测是环境管理的基础性工作,污染源监测报告(数据)的有效性是保证环境执法严肃、公正的重要条件,也是是守法企业展示良好社会形象的基本保证。依照国家的相关规定,并结合行业技术规范的要求,探讨污染源监测报告的有效期问题,以利于相关各方严肃、科学、合理地使用污染源监测数据。 相似文献
76.
Mercury is released to the environment from various anthropogenic and natural sources. This work is a compilation of mercury emissions from anthropogenic sources in Ontario, Canada. The goal of our study was to identify all sources of mercury, and develop an emission inventory of anthropogenic mercury in Ontario. The result of our investigation revealed that combustion of fossil fuels and emissions from landfill sites are two primary sources of mercury to the atmosphere. Other sources of significance are emissions from waste incinerators, various industrial activities, and cement production. Total mercury emission in Ontario is estimated as 4100 kg per year. 相似文献
77.
本文从珠江三角洲地区酸雨监测数据资料入手,对本地区酸雨状况及其趋势进行探讨,研究结果表明,本地区酸雨依然严重,且广泛存在。 相似文献
78.
报导了兰州市一年内大气中TSP及其成分含量的监测结果、污染程度和变化规律,为兰州市进一步治理大气污染,加强环境管理,提高环境质量提供了科学依据。 相似文献
79.
王新兰 《辽宁城乡环境科技》2006,26(1):21-23
利用污染指数法及相关系数法对盘锦市境内的河、海水质进行对比分析,从而得出近岸海域海湾水质主要受入海河流水质影响的结论。 相似文献
80.