滇池细菌总数与有机碳、氮、磷的调查研究

通过对滇池水体一年多的定点采样工作,重点调查研究了草海、外海表层水中细菌数量及有机营养盐碳、氮、磷的季节变化规律,分析探讨了细菌总数与环境条件和有机营养盐之间的某些关系.对滇池富营养治理提出了一些建议,并提出利用微生物学的方法参与这一研究.     

鄂尔多斯遗鸥国家级自然保护区桃-阿海子浮游细菌多样性及其与水体重金属浓度的关联性分析

桃-阿海子是遗鸥(Larus relictus)重要繁殖地,一度趋于干涸,为保护该重要湿地及其中繁殖和迁徙的珍稀鸟类,当地政府启动引黄工程进行补水,所补水为矿井水,矿井水中通常含有大量重金属,重金属又会对水体微生物产生影响,微生物是湖泊生态系统的重要驱动者,且对于生存其中的鸟类具有重要影响。所以为评估所补矿井水对当地生态系统及珍稀候鸟的影响,本研究通过16S rRNA高通量测序的方法分析了鄂尔多斯遗鸥国家级自然保护区桃-阿海子引黄工程注水口1(ZSK1)、注水口2(ZSK2)、湖边(HB)和湖心岛(HXD)4个区域的水样样本中浮游细菌的多样性,并对其与水体重金属元素含量进行关联性分析。结果显示ZSK1和ZSK2水样样本中微生物不存在显著差异,HB和HXD水样样本中微生物多样性不存在显著差异,而ZSK与HB和HXD样本中微生物多样性存在显著差异。微生物群落组成分析发现这几个区域的主要细菌门是变形菌门(Proteobacteria)、拟杆菌门(Bacteroidetes)、厚壁菌门(Firmicutes)、疣微菌门(Verrucomicrobiota)和放线菌门(Actinobacteria),在属水平存在着大量的未知微生物。该区域不同采样点水样中重金属元素含量存在差异,并驱动了微生物群落的构建过程,显著影响4个采样点微生物群落结构的环境变量依次为Pb、Cr和Ni。在HB和HXD样本中耐受重金属的细菌丰度高一些,而在ZSK样本中其丰度较低。该结果对于评估和预测重金属污染等人为活动对微生物群落的影响具有重要意义,并将为鄂尔多斯遗鸥国家级自然保护区桃-阿海子生态环境管理和污染防治提供重要参考,同时为珍稀野生动物保护提供依据。     

序批式生物膜反应器挂膜启动实现短程硝化

常温条件下(20～25℃),以模拟的人工配水为研究对象,采用序批式生物膜反应器(SBBR),在初期挂膜的基础上,笔者运用两种不同的挂膜方式即重新加入新泥和不加新泥而加大进水COD浓度来实现生物膜的快速启动。实验表明,2种挂膜启动通过14 d的培养与富集,NH4+-N与COD的处理效果都能分别达到85%和75%以上。将剩余污泥排尽后,采用第1种挂膜方式的反应器通过连续间歇曝气,达到了比较好的短程硝化效果。调整溶解氧,并且通过先下降后上升曝气量的方式,能进一步提高亚氮的出水。最终在DO为3.6 mg/L时,亚氮的积累率能达到平均74%左右,达到了比较好的亚硝化效果。而第2种挂膜方式培养的生物膜则以好氧反硝化菌为主,去除的氨氮由同化作用和培养的好氧反硝化菌去除,以后者为主。通过比较可以看出,为了实现短程硝化,第1种挂膜方式比第2种更具有优越性,有利于硝化菌种的生长和亚氮的积累,而第2种方式则有利于培养好氧反硝化菌。     

微生物电解池催化CO2电转化为甲烷：影响因素、电子传递和展望

化石燃料作为能源供应的主要来源,燃烧导致大量CO₂的释放和温室效应,CO₂的捕获和再利用越来越受到人们的关注.微生物电解池（MEC）作为一种新的CO₂再利用技术,可通过将电活性微生物与电化学刺激相结合,将CO₂通过生物电化学作用回收为低碳燃料（如CH₄）,从而实现CO₂固定和能量回收.尽管近年来MEC领域有较多研究,但仍然存在许多问题阻碍了该技术的规模化和产业化.本文梳理了CO₂电化学产甲烷的工作原理、性能影响的关键因素、生物阴极电活性功能微生物及其胞外电子传递机制、电催化耦合技术的最新研究进展,提出了MEC辅助CO₂电甲烷化技术的未来研究需求和挑战.     

生物还原-化学沉淀去除烟气SO2中Na2SO3和硫化物的研究

利用硫酸盐还原菌(SRB)和金属离子沉淀剂对烟气SO2进行生物还原-化学沉淀去除,考察了碳源类型、乙酸(碳源)浓度、沉淀剂投加量和反应时间对SO32-去除的影响,研究表明,沉淀剂的加入导致SRB转化产生的S2-能很快生成硫化物沉淀,其它副反应被抑制.乙酸C原子/SO32-的浓度比为1时,SO32-去除最大.随着沉淀剂投加量的增加,SO32-去除率增大.ZnCl2生化反应培养14d后,SO32-去除趋于完全.FeCl2生化反应培养7d后,SO32-去除趋于完全.     

秸秆-复合菌-污泥联合修复铬污染土壤技术

为探索修复Cr（Ⅵ）污染土壤的新方法,以模拟某化工厂铬渣堆存场内Cr（Ⅵ）污染土壤为研究对象,分别研究了秸秆-复合菌-污泥修复铬污染土壤单因素和3因素条件下对铬污染土壤的修复效果。结果表明：单独添加3%的秸秆时,土壤中Cr（Ⅵ）还原率可以达到25.88%;单独添加3%复合菌时,土壤中Cr（Ⅵ）还原率可以达到72.07%;单独添加50%的活性污泥时,土壤中Cr（Ⅵ）还原率可以达85.65%。3个因素中复合菌对土壤中Cr（Ⅵ）还原率的影响最大。综合考虑秸秆、污泥和复合菌3个因素对土壤中Cr（Ⅵ）还原的影响,设计了秸秆、污泥和复合菌的3因素联合实验,最后从修复的经济成本和修复效率考虑,确定最优物料组合为1%秸秆+1%复合菌+30%污泥,对土壤中Cr（Ⅵ）还原率可以达到96.6%。秸秆-复合菌-污泥对铬污染土壤的修复明显高于单独对铬污染土壤修复的效率。该技术在实现对铬污染土壤进行修复的同时,为秸秆和活性污泥的资源化利用开辟了新的途径,实现了\"以废制废\"。     

反硝化菌的偶氮染料脱色研究

从活性污泥中分离到几株反硝化能力的偶氮染料脱色菌。它们在合成培养基吧有使大多数所试偶氮染料脱色,而在反硝化条件下很难使偶氮染料脱色,只有菌株１７在培养２０ｄ后才有较好的脱色效果。酵母粉等有机物作为生长因子时,对菌株１７反硝化条件下的偶氮染料脱色有非常明显的促进作用;     

Characterization of microbial communities from coastal waters using microarrays

Molecular methods, including DNA probes, were used to identify and enumerate pathogenic Vibrio species in the Chesapeake Bay; our data indicated that Vibrio vulnificus exhibits seasonal fluctuations in number. Our work included a characterization of total microbial communities from the Bay; development of microarrays that identify and quantify the diversity of those communities; and observation of temporal changes in those communities. To identify members of the microbial community, we amplified the 16S rDNA gene from community DNA isolated from a biofilm sample collected from the Chesapeake Bay in February, 2000. The resultant 75 sequences were 95% or more similar to 7 species including two recently described Shewanella species, baltica and frigidimarina, that have not been previously isolated from the Chesapeake. When the genera of bacteria from biofilm after culturing are compared to those detected by subcloning amplified 16S fragments from community DNA, the cultured sample exhibited a strong bias. In oysters collected in February, the most common bacteria were previously unknown. Based on our 16S findings, we are developing microarrays to detect these and other microbial species in these estuarine communities. The microarrays will detect each species using four distinct loci, with the multiple loci serving as an internal control. The accuracy of the microarray will be measured using sentinel species such as Aeromonas species, Escherichia coli, and Vibrio vulnificus. Using microarrays, it should be possible to determine the annual fluctuations of bacterial species (culturable and non-culturable, pathogenic and non-pathogenic). The data may be applied to understanding patterns of environmental change; assessing the health of the Bay; and evaluating the risk of human illness associated with exposure to and ingestion of water and shellfish.     

Monitoring of a Coastal Mediterranean Area: Culturable Bacteria, Phytoplankton, Environmental Factors and their Relationships in the Southern Adriatic Sea

Culturable heterotrophic bacterial and phytoplanktonic densities were investigated at four sites in the Southern Adriatic Sea (Brindisi, S. Cataldo, Otranto and S. M. di Leuca) over an annual cycle. The main phytoplankton groups, the bacterial biodiversity, as well as the faecal contamination indicators were determined. Culturable bacterial numbers averaged 4.8 ± 0.2 log CFU ml⁻¹ whereas phytoplankton numbers averaged 2.1 ± 0.4 log cells ml⁻¹. Relationships between culturable bacteria, phytoplankton and the environmental factors were established. Bacterial and phytoplankton densities usually depended significantly on temperature, dissolved oxygen, phosphate and nitrite only in the S. Cataldo transect. In all the examined transects phytoplankton showed a bloom during the January–February period followed by a bacterial peak during the February–March period. Thus we can suppose that the phytoplankton winter bloom is responsible for the availabily of organic matter for bacterial populations in the following months in this oligotrophic ecosystem.     

水环境中致病菌分子生物学检测技术研究进展

总结了水环境中主要致病菌及其导致的疾病;介绍了检测水环境样品中致病菌的聚合酶链式反应（PCR）、实时定量PCR、等温扩增技术、生物传感器和高通量测序等分子生物学技术研究进展;分析了不同检测技术的优缺点和应用特点;提出了水环境中致病菌分子生物学检测技术的未来发展方向,为水环境中致病菌分析检测和风险控制提供研究思路和技术支撑。