The Dynamics of Species Composition and Abundance of Wasps from the Families Pompilidae, Sphecidae, and Vespidae (Hymenoptera: Aculeata) in Successional Pine Biogeocenoses of the Berezinskii Biosphere Reserve

The data on the dynamics of population size and species composition of wasps from the families Pompilidae, Sphecidae, and Vespidae were obtained in the course of long-term studies carried out in successional pine forests of the Berezinskii Biosphere Reserve. The abundance and species diversity of wasps were significantly higher in a polewood forest (40 years) than in a young forest (20 years) and mature moss forest (70 years). In an overgrown ride in the moss pine forest, the composition of dominant wasp species remained relatively stable during the seven-year period of observations, although the number of species and their abundance varied significantly from year to year, depending on the weather.     

不同环境条件下偶氮染料酸性大红GR的生物降解性能

为了考察不同环境条件下偶氮染料酸性大红GR生物降解性能,采用已驯化的混合菌群作为接种液进行偶氮染料酸性大红GR脱色试验。结果表明,微氧条件下(静置敞口培养),偶氮染料酸性大红GR脱色效果最佳,染料脱色主要发生在菌体的对数生长期。混合菌群对pH、温度适应范围较广,pH为3.32~9.18,温度在20℃~37℃范围内均可以获得较好脱色效果,脱色率均在80%以上。微氧条件下酸性大红GR降解历程表明,偶氮基整个共轭系统被破坏,生成了一种新的结构,使原有的某些精细结构在二阶导数光谱中得以表现,由此探讨其生物降解机理。     

三步法处理大港油田12井综合废水的实验研究

根据大港油田12井综合废水的污染特征,提出了"混凝-内电解-H2O2氧化"三步处理的方法。实验结果表明:三步法处理后可以使原水的CODcr从4930mg/L降低到128mg/L,去除率达到97%。处理后水质达到国家《污水综合排放标准》(GB8978-1996)二级标准要求。     

A Procedure for NEPA Assessment of Selenium Hazards Associated With Mining

This paper gives step-by-step instructions for assessing aquatic selenium hazards associated with mining. The procedure was developed to provide the U.S. Forest Service with a proactive capability for determining the risk of selenium pollution when it reviews mine permit applications in accordance with the National Environmental Policy Act (NEPA). The procedural framework is constructed in a decision-tree format in order to guide users through the various steps, provide a logical sequence for completing individual tasks, and identify key decision points. There are five major components designed to gather information on operational parameters of the proposed mine as well as key aspects of the physical, chemical, and biological environment surrounding it — geological assessment, mine operation assessment, hydrological assessment, biological assessment, and hazard assessment. Validation tests conducted at three mines where selenium pollution has occurred confirmed that the procedure will accurately predict ecological risks. In each case, it correctly identified and quantified selenium hazard, and indicated the steps needed to reduce this hazard to an acceptable level. By utilizing the procedure, NEPA workers can be confident in their ability to understand the risk of aquatic selenium pollution and take appropriate action. Although the procedure was developed for the Forest Service it should also be useful to other federal land management agencies that conduct NEPA assessments, as well as regulatory agencies responsible for issuing coal mining permits under the authority of the Surface Mining Control and Reclamation Act (SMCRA) and associated Section 401 water quality certification under the Clean Water Act. Mining companies will also benefit from the application of this procedure because priority selenium sources can be identified in relation to specific mine operating parameters. The procedure will reveal the point(s) at which there is a need to modify operating conditions to meet environmental quality goals. By recognizing concerns early in the NEPA process, it may be possible for a mining company to match operational parameters with environmental requirements, thereby increasing the likelihood that the permit application will be approved.     

Heavy metal contamination in the vicinity of an industrial area near Bucharest

BACKGROUND, AIMS AND SCOPE: Chromium enters into the aquatic environment as a result of effluent discharge from steel works, electroplating, leather tanning industries and chemical industries. As the Cr(VI) is very harmful to living organisms, it should be quickly removed from the environment when it happens to be contaminated. Therefore, the aim of this laboratory research was to develop a rapid, simple and adaptable solvent extraction system to quantitatively remove Cr(VI) from polluted waters. METHODS: Aqueous salt-solutions containing Cr(VI) as CrO4(2-) at ppm level (4-6 ppm) were prepared. Equal volumes (5 ml) of aqueous and organic (2-PrOH) phases were mixed in a 10 ml centrifuge tube for 15 min, centrifuged and separated. Concentrations of Cr(VI), in both the aqueous and organic phases, were determined by atomic absorption spectrometry. The effects of salt and acid concentrations, and phase-contact time on the extraction of Cr(VI) were investigated. In addition, the extraction of Cr(VI) was assessed in the presence of tetramethylammonium chloride (TMAC) in 2-PrOH phase. Effects of some other metals, (Cd(II), Co(II), Cu(II), Ni(II) and Zn(II)), on the extraction of Cr(VI) were also investigated. RESULTS AND DISCUSSION: The Cr(VI) at ppm level was extracted quantitatively by salting-out the homogeneous system of water and 2-propanol(2-PrOH) using chloride salts, namely CaCl2 or NaCl, under acidic chloride media. The extracted chemical species of Cr(VI) was confirmed to be the CrO3Cl-. The ion-pair complex extracted into the organic phase was rationalized as the solvated ion-pair complex of [2-PrOH2+, CrO3Cl-]. The complex was no longer stable. It implied the reaction between extracted species. Studies revealed that salts and acid directly participated in the formation of the above complex. Use of extracting agents (TMAC) didn't show any significant effect on the extraction of Cr(VI) under high salting-out conditions. There is no significant interference effect on the extraction of Cr(VI) by the presence of other metals. The Cr(VI) in the organic phase was back-extracted using an aqueous ammonia solution (1.6 mol dm(-3)) containing 3 mol dm(-3) NaCl. The extraction mechanism of Cr(VI) is also discussed. CONCLUSIONS: Salting-out of homogeneous mixed solvent of 2-propanol can be employed to extract Cr(VI) quantitatively, as an ion-pair of [2-PrOH2+ * CrO3Cl-] solvated by 2-PrOH molecules. Then, the complex becomes 'solvent-like' and is readily separated into the organic phase. The increase of Cl- ion concentration in the aqueous phase favors the extraction. The 2-PrOH, salts and acid play important roles in the extraction process. There is no need to use an extracting agent at a high salting-out condition. RECOMMENDATIONS AND PERSPECTIVES: Chromium(VI) must be quickly removed before it enters into the natural cycle. As the 2-PrOH is water-miscible in any proportion, ion-pairing between 2-PrOH2+ and CrO3Cl- becomes very fast. As a result, Cr(VI) can easily be extracted. Therefore, the method is recommended as a simple, rapid and adaptable method to quickly separate Cr(VI) from aqueous samples.     

农村混合生活污水排放特征及其处理工艺研究

针对农村生活污水污染问题已成为影响我国农村水环境的主要因素以及目前黑灰分离收集处理与现状不相符合,本文对崇明县某村的污水排放特征以及水量水质进行调研,并对硝化预处理系统结合人工湿地反硝化以及脱氮预处理结合人工湿地深度处理两种运行模式进行了深入探讨并分析了其去除机理,结果显示,硝化预处理系统结合人工湿地反硝化由于后续反硝化需要投加大量碳源从经济管理方面而言变得不可行;脱氮预处理结合人工湿地深度处理在预处理系统以进水3h、曝气2h、沉淀0.5h、排水0.5h、气水比40∶1的模式运行、人工湿地水力停留时间为48h条件下出水可满足《城镇污水处理厂污染物排放标准》(GB18918-2002)的二级要求,且因氨氮指标的降低大幅缩短了人工湿地的水力停留时间而减小占地面积。     

Identification of rice cultivars with low brown rice mixed cadmium and lead contents and their interactions with the micronutrients iron, zinc, nickel and manganese

Paddy fields in mining areas are usually co-contaminated by a cocktail of mixed toxic heavy metals (e.g., Cd and Pb in Pb/Zn mines). However, previous studies on rice cultivars screened for effective metal exclusion have mostly focused on individual metals, and have been conducted under pot-trial or hydroponic solution conditions. This study identified rice cultivars with both low Cd and Pb accumulation under Cd-and Pb-contaminated field conditions, and the interactions of the toxic elements Cd and Pb with the micronutrient elements Fe, Zn, Mn and Ni were also studied. Among 32 rice cultivars tested, there were significant differences in Cd (0.06-0.59 mg/kg) and Pb (0.25-3.15 mg/kg) levels in their brown rice, and similar results were also found for the micronutrient elements. Significant decreases in concentrations of Fe and Mn were detected with increasing Cd concentrations and a significant elevation in Fe, Mn and Ni with increasing Pb concentrations. A similar result was also shown by Cd and Ni. Three cultivars were identified with a combination of low brown rice Cd and Pb, high micronutrient and grain yield (Wufengyou 2168, Tianyou 196 and Guinongzhan). Present results suggest that it is possible to breed rice cultivars with low mixed toxic element (Cd, Pb) and high micronutrient contents along with high grain yields, thus ensuring food safety and quality.     

“污泥+生物质”混合厌氧消化分类管理研究

污泥单独厌氧消化困难,产气量低,能量回收价值低.但“污泥+生物质”混合厌氧消化能够改善物料间的营养平衡,运行更平稳,既有效处理污泥,又能够提高甲烷产气量,更适合生产实际,符合行业发展趋势.分析了安阳市四家污水处理厂脱水污泥的重金属含量,依据土地利用限值标准,结合生产实际,把安阳市四个污水处理厂脱水污泥分类,分类混合厌氧消化处理后分类土地利用,既提高了污泥的土地利用,更强化了污泥土地利用的重金属管理.     

进水底物浓度对蔗糖废水产酸合成PHA影响研究

混合菌群合成生物可降解塑料(PHA)成为目前研究的热点,三段式PHA合成工艺(水解产酸、产PHA菌富集、PHA合成)被广泛应用.在三段式工艺中,产PHA菌的富集非常关键,只有稳定产生PHA菌才能保障PHA合成的产量.针对产PHA菌富集系统容易出现污泥膨胀的问题,本研究考察了进水底物浓度对产PHA菌富集效率及运行稳定性的影响.在560mg·L-1、1 120 mg·L-1、1 680 mg·L-1这3组不同进水底物浓度的对比实验中,证实了COD 1 120 mg·L-1条件下富集反应器能够在较短污泥龄下稳定富集具有较高污泥浓度的高效产PHA菌,且不会发生污泥膨胀.在94 d的富集期后其批次实验最大PHA含量、PHA转化率(COD/COD)及PHA比合成速率能分别达到50%、0.714 5及0.191 2 mg·(mg·h)-1.研究还同时证实细胞内糖原水平高低与其PHA合成能力密切相关,可采用其作为富集效果的重要检测指标之一.     

混合培养微生物好氧降解对硝基苯胺的特性研究

通过富集培养 ,获得了降解对硝基苯胺的混合培养微生物。结果表明 ,对硝基苯胺降解速度和混合培养微生物生长对外加碳源有较强的依赖性。在培养液中添加 1 0g L葡萄糖和 1 0g L酵母粉 ,36h内对硝基苯胺去除率可达97%以上 ,对硝基苯胺降解速率可达 4 1mg L·h ;当对硝基苯胺作为培养液生长的唯一碳源、氮源和能源时 ,96h内对硝基苯胺去除率为 34 8% ,降解速率为 0 15mg L·h。