全文获取类型
收费全文 | 538篇 |
免费 | 8篇 |
国内免费 | 65篇 |
专业分类
废物处理 | 2篇 |
环保管理 | 74篇 |
综合类 | 153篇 |
基础理论 | 93篇 |
污染及防治 | 186篇 |
评价与监测 | 77篇 |
社会与环境 | 23篇 |
灾害及防治 | 3篇 |
出版年
2023年 | 4篇 |
2022年 | 10篇 |
2021年 | 3篇 |
2020年 | 7篇 |
2019年 | 8篇 |
2018年 | 9篇 |
2017年 | 14篇 |
2016年 | 25篇 |
2015年 | 13篇 |
2014年 | 17篇 |
2013年 | 57篇 |
2012年 | 28篇 |
2011年 | 73篇 |
2010年 | 32篇 |
2009年 | 50篇 |
2008年 | 55篇 |
2007年 | 34篇 |
2006年 | 30篇 |
2005年 | 14篇 |
2004年 | 17篇 |
2003年 | 16篇 |
2002年 | 15篇 |
2001年 | 14篇 |
2000年 | 9篇 |
1999年 | 5篇 |
1998年 | 14篇 |
1997年 | 12篇 |
1995年 | 5篇 |
1994年 | 6篇 |
1993年 | 3篇 |
1992年 | 3篇 |
1988年 | 2篇 |
1985年 | 2篇 |
1984年 | 1篇 |
1982年 | 1篇 |
1978年 | 1篇 |
1973年 | 1篇 |
1968年 | 1篇 |
排序方式: 共有611条查询结果,搜索用时 15 毫秒
321.
Tilman Floehr Björn Scholz-Starke Hongxia Xiao Josef Koch Lingling Wu Junli Hou Anja Wolf Axel Bergmann Kerstin Bluhm Xingzhong Yuan Martina Roß-Nickoll Andreas Schäffer Henner Hollert 《环境科学学报(英文版)》2015,38(12):63-82
Besides obvious benefits,the Three Gorges Dam's construction resulted in new pollution scenarios with the potentials to threaten the Three Gorges Reservoir(TGR) ecosystem.In order to record organic contamination,to find links to ecotoxicological impacts and to serve as reference for ensuing monitoring,several sites in the TGR area were screened applying the triad approach with additional lines-of-evidence as a holistic assessment method.Sediments and the benthic fish species Pelteobagrus vachellii were sampled in 2011 and 2012 to determine organic pollution levels,mutagenic potentials and genotoxic impacts.Two regional hot-spots near the cities of Chongqing and Kaixian were identified and further investigated in 2013.Only polycyclic aromatic hydrocarbons(PAHs) could be detected in sediments in 2011(165–1653 ng/g),emphasizing their roles as key pollutants of the area.Their ubiquity was confirmed at Chongqing(150–433 ng/g) and Kaixian(127–590 ng/g) in2013.Concentrations were comparable to other major Chinese and German rivers.However,the immense sediment influx suggested a deposition of 216–636 kg PAH/day(0.2–0.6 mg PAH/(m2·day)),indicating an ecotoxicological risk.PAH source analysis highlighted primary impacts of combustion sources on the more industrialized upper TGR section,whereas petrogenic sources dominated the mid-low section.Furthermore,sediment extracts from several sites exhibited significant activities of frameshift promutagens in the Ames fluctuation assay.Additionally,significant genotoxic impairments in erythrocytes of P.vachellii were detected(Chongqing/Kaixian),demonstrating the relevance of genotoxicity as animportant mode of action in the TGR's fish.PAHs,their derivatives and non-target compounds are considered as main causative agents. 相似文献
322.
Kamal El Kadi Abderrezzak André Paquier Bernard Gay 《Environmental Fluid Mechanics》2008,8(2):169-198
This paper reports a numerical study on dam-break waves over movable beds. A one-dimensional (1-D) model is built upon the
Saint-Venant equations for shallow water waves, the Exner equation of sediment mass conservation and a spatial lag equation
for non-equilibrium sediment transport. The set of governing equations is solved using an explicit finite difference scheme.
The model is tested in various idealized experimental cases, with fairly good agreement between the numerical predictions
and measurements. Discrepancies are observed at the earlier stage of the dam-break wave and around the dam location due to
no vertical velocity component being taken into account. Sensitivity tests confirm that the friction coefficient is an important
parameter for the evaluation of sediment transport processes operating during a dam-break wave. The influence of the non-equilibrium
adaptation length (or the lag distance) is negligible on the wavefront celerity and weak on the free surface and bed profiles,
which indicates that one may ignore the spatial lag effect in dam-break wave studies. Finally, the simulation of the Lake
Ha!Ha! dyke-break flood event shows that the model can provide relevant results if a convenient formula for computing the
sediment transport capacity and an appropriate median grain diameter of riverbed material are selected. 相似文献
323.
对连云港市商业区路边沉积物中Pb和Cu的含量及污染程度进行了调查。结果表明,连云港市商业区路边沉积物中Pb的算术平均值为97.24mg/kg。是我国A层土壤算术平均值的3.7倍,沉积物中Cu的算术平均值为49.99mg/kg。是我国A层土壤算术平均值的2.24倍;沉积物中Cu含量分布变异性比Pb含量高。地累积指数的评价结果表明,沉积物中Pb比Cu污染严重。 相似文献
324.
陈秋兰 《环境监测管理与技术》2019,31(3):49-52
沉积物样品用乙腈-柠檬酸缓冲溶液提取后经HLB-SPE柱净化,采用LC-MS/MS法在MRM模式下测定17种磺胺类和4种四环素类抗生素,通过优化测定条件,使方法在0. 500μg/kg~100μg/kg范围内线性良好。方法检出限为0. 15μg/kg~1. 2μg/kg,2个质量比水平的加标回收率为44. 1%~125%,试验5次结果的RSD 16. 0%。将该方法用于测定厦门近岸海域沉积物中抗生素,共有6种磺胺类和4种四环素类抗生素检出,测定值为0. 3μg/kg~26. 2μg/kg。 相似文献
325.
Fang Zhang Hao Zhang Ying Yuan Dun Liu Chenyu Zhu Di Zheng Guanghe Li Yuquan Wei Dan Sun 《Frontiers of Environmental Science & Engineering》2020,14(2):28
326.
利用计算机研制了一个简易的污染底泥资源化选择软件系统,该软件采用多种污染底泥资源化方式对比结构和模块化程序设计方法,并根据最佳用户体验制造出简易和良好的运行环境和用户界面。将该软件系统用于温州市三垟湿地污泥、广州海珠湿地公园水体污泥、珠江三角洲湿地污泥的资源化选择,结果表明除温州市三垟湿地污泥适合填埋之外,其余2个地区的污泥可以作为农用施肥。 相似文献
327.
佛山水道底泥重金属污染调查 总被引:18,自引:5,他引:13
为了解佛山水道底泥的污染状况,对佛山水道底泥重金属的总体水平及其潜在生态危害进行了调查.结果表明,佛山水道底泥重金属的质量比处于较高水平,Hg的平均质量比达到背景值的20倍,As的平均质量比是背景值的2倍多.根据潜在生态危害指数法的评价结果,佛山水道底泥重金属对生态系统的危害已达到很强的程度;各种重金属的生态危害排序为:Hg>Cd>Pb>Cu>As>Cr>Zn,其中Hg的生态危害已达到了极强的程度. 相似文献
328.
Environmental and economic analysis of switchgrass production for water quality improvement in northeast Kansas 总被引:2,自引:0,他引:2
The primary objectives of this research were to determine SWAT model predicted reductions in four water quality indicators (sediment yield, surface runoff, nitrate nitrogen (NO(3)-N) in surface runoff, and edge-of-field erosion) associated with producing switchgrass (Panicum virgatum) on cropland in the Delaware basin in northeast Kansas, and evaluate switchgrass break-even prices. The magnitude of potential switchgrass water quality payments based on using switchgrass as an alternative energy source was also estimated. SWAT model simulations showed that between 527,000 and 1.27 million metric tons (Mg) of switchgrass could be produced annually across the basin depending upon nitrogen (N) fertilizer application levels (0-224 kg N ha(-1)). The predicted reductions in sediment yield, surface runoff, NO(3)-N in surface runoff, and edge-of-field erosion as a result of switchgrass plantings were 99, 55, 34, and 98%, respectively. The average annual cost per hectare for switchgrass ranged from about 190 US dollars with no N applied to around 345 US dollars at 224 kg N ha(-1) applied. Edge-of-field break-even price per Mg ranged from around 41 US dollars with no N applied to slightly less than 25 US dollars at 224 kg N ha(-1) applied. A majority of the switchgrass produced had an edge-of-field break-even price of 30 Mg(-1) US dollars or less. Savings of at least 50% in each of the four water quality indicators could be attained for an edge-of-field break-even price of 22-27.49 US dollars Mg(-1). 相似文献
329.
射阳河底泥重金属沿程变化分析及污染评价 总被引:2,自引:0,他引:2
分析了射阳河流域沿程20个底泥样品中6种重金属(Cr、Pb、Ni、Zn、Cu、As)的含量,并应用地累积指数法对其进行了污染评价。研究结果表明:除As在近一半的采样点没有污染,其他重金属污染均普遍存在,但多数属于轻度污染。Zn污染最为严重,几乎全程都是偏中等或中等以上的污染。纵观射阳河全程样品FN04,SY07污染最为严重,前者与其支流西塘河的污染有关,后者可能与河闸上侧的死水状态有关;黄沙河污染最轻,与河流沉积物粒径比较粗而导致的对重金属吸附能力减弱有关。 相似文献
330.
底泥疏浚对五里湖沉积物生物毒性的影响 总被引:4,自引:0,他引:4
为评价疏浚对太湖五里湖沉积物毒性的影响,采用淡水沉积物重金属质量基准和发光细菌试验法对疏浚前后太湖五里湖沉积物的生态毒性风险进行了分析.结果显示,疏浚后,尽管沉积物中Cu和Zn的总体含量降低至毒性效应低值(TEL/TEC)以下,Cr、Pb和Ni等重金属的总体含量降低至毒性效应最高值(PEL/PEC)以下,但沉积物提取液对发光菌的毒性却显著增加,且在疏浚后1个月时毒性最大,其EC25和EC50最小,分别仅为0.51%和9.16%.这表明,疏浚尽管可有效减少沉积物中重金属污染物总体含量,但并不能完全消除沉积物的生态毒性风险;相反,还有可能导致其生态毒性的风险性进一步增加. 相似文献