High-throughput metagenomic analysis of petroleum-contaminated soil microbiome reveals the versatility in xenobiotic aromatics metabolism

The soil with petroleum contamination is one of the most studied soil ecosystems due to its rich microorganisms for hydrocarbon degradation and broad applications in bioremediation.However, our understanding of the genomic properties and functional traits of the soil microbiome is limited. In this study, we used high-throughput metagenomic sequencing to comprehensively study the microbial community from petroleum-contaminated soils near Tianjin Dagang oilfield in eastern China. The analysis reveals that the soil metagenome is characterized by high level of community diversity and metabolic versatility. The metageome community is predominated by γ-Proteobacteria and α-Proteobacteria, which are key players for petroleum hydrocarbon degradation. The functional study demonstrates over-represented enzyme groups and pathways involved in degradation of a broad set of xenobiotic aromatic compounds, including toluene, xylene, chlorobenzoate, aminobenzoate, DDT, methylnaphthalene, and bisphenol. A composite metabolic network is proposed for the identified pathways, thus consolidating our identification of the pathways. The overall data demonstrated the great potential of the studied soil microbiome in the xenobiotic aromatics degradation. The results not only establish a rich reservoir for novel enzyme discovery but also provide putative applications in bioremediation.     

超声降解水中的磺胺嘧啶

以磺胺嘧啶(SD)为研究对象,探讨了超声功率、初始浓度、pH值以及超声协同H2O2、Fenton、TiO2等组合工艺对超声降解SD效率的影响。实验结果表明,超声可有效降解水中低浓度的SD,尤其在酸性条件下,超声降解更为显著,降解过程遵循准二级反应动力学模型。加入H2O2或TiO2可在一定程度上促进SD的超声降解,加入Fenton试剂则显著提升SD的去除率。依据量化计算以及LC-MS测定结果,探讨了SD的超声降解机理。超声降解水中SD主要是基于.OH自由基的氧化过程。     

聚合氯化铝中纳米Al13形态的分离纯化及形态表征

采用超滤法和层析法分离纯化聚合氯化铝(PAC)中的Al₁₃形态,并采用Al-Ferron逐时络合比色法、²⁷Al-NMR、TEM和粒度测定仪对分离纯化所得的Al₁₃形态进行了分析和表征.研究结果表明,超滤法分离纯化的效果受超滤膜的孔径及PAC浓度的影响,选择合适孔径的膜和PAC溶液浓度即可以获得高纯度的Al₁₃,在层析法中则随着洗脱时间延长按分子的大小依次洗脱下来,因此截取中间组分即可得到Al₁₃;Al-Ferron逐时络合比色法和²⁷Al-NMR的分析结果表明,采用上述2种方法分离提纯得到的样品中Al₁₃的含量分别可达到90%以上和100%.TEM和粒度测定结果表明,在B=2.5的PAC溶液中,Al₁₃极少以Al₁₂AlO₄(OH)₂₄(H₂O)⁷⁺₁₂的单体形态存在,而是呈两维结构的线性和枝状的聚集体,Al₁₂AlO₄(OH)₂₄(H₂O)⁷⁺₁₂的聚集体尺寸通常在几十至几百nm.     

垂直防渗帷幕在平原型卫生填埋场中的运用

通过具体的工程实例论述垂直防渗帷幕在平原型卫生填埋场中的功能与作用,以及对3种常用的垂直防渗型式作了比较,对在填埋场工程中垂直防渗型式的选择提出了建议。     

Cd2+和Pb2+对四环素超声降解性能的影响

通过紫外分光光度法,研究了Cd2+和Pb2+对四环素超声降解过程的影响。研究结果表明,Cd2+和Pb2+在水中与四环素发生络合反应后,在紫外光谱上发生蓝移,在206 nm处产生新的峰值。同时,在低摩尔比(四环素:重金属2+和Pb2+可以加快四环素的超声降解。0.01 mmol/L四环素溶液24 h的超声降解率为7.54%,加入Pb2+和Cd2+离子后,四环素去除率分别升高至20.82%和18.75%。在高摩尔比(四环素:重金属>2)时,Cd2+和Pb2+抑制了四环素的降解,在0.08 mmol/L四环素溶液中,加入Pb2+和Cd2+离子反而使四环素去除率从4.69%分别降低至2.04%和1.40%。     

产业布局生态适宜性评价及案例研究

从产业布局的生态适宜性研究进展入手,提出产业布局的生态适宜性评价应该以产业布局的影响因素分析为基础,以产业布局对经济发展、资源消耗、污染排放的影响程度分析为重点。在此基础上构建了涵盖5个层次的产业布局生态适宜性评价指标体系,并以铁岭市为例评价了该市的产业布局水生态适宜性。分析表明：调兵山市、开原市、铁岭县在铁岭市各区、市、县中产业布局的水生态适宜性相对较高,影响铁岭市产业布局水生态适宜性水平的主要因子包括资源环境效应因子和经济效应因子。从优化产业结构,协调产业布局与水资源、水环境关系等方面提出了铁岭市产业布局优化的对策。     

能源煤化工基地产业链评价与优化对策

在能源煤化工基地工业系统分析的基础上,提出延伸产业链、拓宽生态位,及加强产业链耦合等产业链优化技术途径,并选取宁东能源煤化工基地进行典型案例分析。利用企业间关联度和废弃物资源化率两项指标对宁东能源煤化工基地的食物链（网）进行分析评价。分析得出,宁东能源煤化工基地的企业间总关联度为0.378,表明基地内各工业种群间联系较紧密,产业链结构基本合理;固体废物资源化率为10.69%,废水资源化率为9.91%,表明基地内固体废物及废水资源均未得到充分利用。据此提出开展重点技术研发、发展补链型产业、建立企业联盟等宁东能源煤化工基地产业链优化对策。     

建筑与火灾

火灾同水灾、地震、雷电等灾害一样,其历史已大大超过人类的生存史。但是人类认识、研究和建立火灾学科体系,却比其他灾害晚得多,这是因火灾的突发性、蔓延性和复杂的不确定性等原凶,使人们系统的、深入地认识并防消火灾的难度增大。     

A new comprehensive ecological risk index for risk assessment on Luanhe River,China

With the enhancement of human activities which influence the physical and chemical integrity of ecosystem, it was bound to increase ecological risk to the ecosystem, and the risk assessment of small scale, single pollutant, or only on water quality have been not satisfied the demand of sustainable development of basin water environment. Based on the response relationship between environmental flow requirements guarantee ratio (GEF) and river ecological risk index (ERI), the Sediment Quality Guideline Quotient index (SQG-Q), and the Biotic Index (BI), we construct a new comprehensive ecological risk index (CERI) to evaluate the ecological risk of Luanhe River, China. According to the response relationship between GEF and ERI, upper and lower reaches of Luanhe River (Goutaizi to Hanjiaying) were at moderate risk level (0.41 < ERI < 0.56) in dry season, and all sites were at low risk level (ERI < 0.40) in wet season; considering the contribution of heavy metals contamination in the SQG-Q, the Luanhe River was the most influenced by higher levels of heavy metals in dry season and wet season; when this index was applied to the PAHs levels, only 30 and 20% of the sampling sites appeared to be moderately impacted (0.1 < SQG-Q PAHs < 0.5) by the PAHs in dry season and wet season, respectively. The results of BI showed that half of the sites appeared to be at moderately polluted level (50% of the sites, 0.25 < BI < 0.32) and heavily polluted level (Zhangbaiwan, BI = 0.36) in dry season, and 40% of the sites appeared to be at moderately polluted level (0.26 < BI < 0.29) in wet season. The CERI showed that 70 and 30% of the sites were at moderate risk level in dry season (0.25 < CERI < 0.36) and wet season (0.26 < CERI < 0.29), respectively. The results could give insight into risk assessment of water environment and decision-making for water source security.

     

环境影响评价工作中的问题及解决途径

随着人们对环境问题的日益关注,环境影响评价工作(环评)的重要性日益凸显。当前,环评工作存在低效推进、从业人员素质偏低、公众片面参与等问题,这在一定程度上会影响环境保护效果。本文以现有问题为导向,提出相应的解决途径,旨在改善环境质量。