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711.
We compared naturally alkaline streams with limestone lithology to freestone streams with and without acid mine drainage (AMD) to predict benthic macroinvertebrate community recovery from AMD in limestone-treated watersheds. Surrogate-recovered (limestone) and, in many cases, freestone systems had significantly higher macroinvertebrate densities; diversity; taxa richness; Ephemeroptera, Plecoptera, and Trichoptera (EPT) taxa; EPT/chironomid ratios; scraper/collector-gatherer ratios; herbivores; collector-filterers; and scrapers. AMD-influenced systems had significantly greater numbers of Diptera and collector-gatherers. An entire trophic level (herbivores) was "restored" in surrogate-recovered streams, which also showed greater trophic specialization. Indicator analysis identified seven taxa (within Crustacea, Diptera, Nematoda, Trichoptera, and Ephemeroptera) as significant indicators of limestone systems and six taxa (within Ephemeroptera, Plecoptera, Tricoptera, Coleoptera, and Mollusca) as significant freestone indicators, all useful as biological indicators of recovery from AMD. 相似文献
712.
Edward R. Long R. Scott Carr James M. Biedenbach Sandra Weakland Valerie Partridge Margaret Dutch 《Environmental monitoring and assessment》2013,185(1):755-775
Data from toxicity tests of the pore water extracted from Puget Sound sediments were compiled from surveys conducted from 1997 to 2009. Tests were performed on 664 samples collected throughout all of the eight monitoring regions in the Sound, an area encompassing 2,294.1 km2. Tests were performed with the gametes of the Pacific purple sea urchin, Strongylocentrotus purpuratus, to measure percent fertilization success as an indicator of relative sediment quality. Data were evaluated to determine the incidence, degree of response, geographic patterns, spatial extent, and temporal changes in toxicity. This is the first survey of this kind and magnitude in Puget Sound. In the initial round of surveys of the eight regions, 40 of 381 samples were toxic for an incidence of 10.5 %. Stations classified as toxic represented an estimated total of 107.1 km2, equivalent to 4.7 % of the total area. Percent sea urchin fertilization ranged from >100 % of the nontoxic, negative controls to 0 %. Toxicity was most prevalent and pervasive in the industrialized harbors and lowest in the deep basins. Conditions were intermediate in deep-water passages, urban bays, and rural bays. A second round of testing in four regions and three selected urban bays was completed 5–10 years following the first round. The incidence and spatial extent of toxicity decreased in two of the regions and two of the bays and increased in the other two regions and the third bay; however, only the latter change was statistically significant. Both the incidence and spatial extent of toxicity were lower in the Sound than in most other US estuaries and marine bays. 相似文献
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含钒石煤生产五氧化二钒污染治理 总被引:1,自引:1,他引:0
介绍用含钒石煤生产五氧化二钒的原理和低污染生产工艺。论述了五氧化二钒生产中废水、废气、废渣、噪声的产生及其废水、废气、噪声的治理方法与效果。并介绍了废渣的处置与综合利用技术及五氧化二钒生产可能带来的放射性影响及防护措施。 相似文献
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Aaron D. Peacock David B. Hedrick Philip E. Long Kelly P. Nevin Charles T. Resch Derek R. Lovley David C. White 《补救:环境净化治理成本、技术与工艺杂志》2011,21(4):85-106
At the Old Rifle uranium mill‐tailing site in eastern Colorado, a test of subsurface amendment with acetate to stimulate the reductive immobilization of uranium was monitored by using lipid biomarker analysis and incorporation of 13C‐labeled acetate into lipid biomarkers. Both sediment and groundwater samples were analyzed. Within 7 days of acetate addition, groundwater microbial biomass increased by a factor of 5, and remained higher than control values in most samples for the 28 days sampled. At 29 days after the beginning of acetate amendment, 4 of 12 sediment samples had microbial biomass greater than the 95 percent confidence interval of controls. The mole percents of the phospholipid fatty acids 16:1ω7c and 16:1ω5c increased over control values upon acetate amendment, and incorporated high levels of 13C from labeled acetate in groundwater and sediment samples. 16:1ω7c is a biomarker for Geobacter, and evidence is provided that 16:1ω5c represents an unidentified iron‐reducing bacterium, probably a member of the Desulfobulbaceae. Biomarkers for organisms other than iron‐reducing bacteria, iso‐ and anteiso‐branched fatty acids and 18:1ω9c, decreased upon acetate amendment, and had their highest stable isotope incorporation at least 4 days after labeled acetate amendment ended, evidence for carbon‐sharing between iron‐reducers and other microorganisms. © 2011 Wiley Periodicals, Inc. 相似文献
719.
Mg/Al水滑石对水中痕量邻苯二甲酸酯的吸附动力学和热力学 总被引:1,自引:1,他引:0
研究了Mg/A1水滑石对水中痕量邻苯二甲酸二甲酯(DMP)、邻苯二甲酸二(2一乙基己基)酯(DEHP)和邻苯二甲酸二辛酯(DnOP)的吸附动力学和热力学特性。结果表明,在所研究的浓度范围内,3种邻苯二甲酸酯的吸附动力学曲线均符合准二级速率方程,DMP、DEHP和DnOP分别在600、200和200min基本达到吸附平衡;3种邻苯二甲酸酯的吸附等温线基本符合Langmuir和Freundlich吸附等温方程;在283~308K范围,pH=6.36,3种邻苯二甲酸酯初始浓度均为50μg/L时,吸附过程△H为负值且绝对值为5~12kJ/mol,表明吸附为放热过程,以表面物理吸附为主,邻苯二甲酸酯在Mg/Al水滑石上的吸附是色散力、诱导力、取向力和氢键力等多种作用力协同作用的结果。 相似文献
720.
以不同n (Al )1 n (SiO 2 )的Al -SiO 2 介孔材料为吸附剂处理电解锰废水,并利用中卜组合设计法研究电解锰废水中锰离子与铬离子(包括铬(!和铬(")的相互作用对材料吸附性能的影响.实验结果表明:以n (Al )1 n (SiO 2 )为1:1 的Al -SiO 2 介孔材料为吸附剂,当吸附剂加入量... 相似文献