Download or read book Characterization of Microbial Communities in TCE Contaminated Seep Zone Sediments written by and published by . This book was released on 2005 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: Hundreds of sites across the United States contain trichloroethene (TCE) contamination, including the Department of Energy's Savannah River Site (SRS) in Aiken, South Carolina. Previous studies have indicated that microorganisms are capable of efficiently degrading TCE to nonhazardous end products. In this project, molecular and growth based methods were used for microbial characterization of a TCE impacted seepzone where TCE degradation is naturally occurring. The results from this work provide clear evidence that the SRB may play a significant role in TCE degradation along the Twin Lakes seepline.

Download or read book Contaminants in the Subsurface written by National Research Council and published by National Academies Press. This book was released on 2005-04-23 with total page 371 pages. Available in PDF, EPUB and Kindle. Book excerpt: At hundreds of thousands of commercial, industrial, and military sites across the country, subsurface materials including groundwater are contaminated with chemical waste. The last decade has seen growing interest in using aggressive source remediation technologies to remove contaminants from the subsurface, but there is limited understanding of (1) the effectiveness of these technologies and (2) the overall effect of mass removal on groundwater quality. This report reviews the suite of technologies available for source remediation and their ability to reach a variety of cleanup goals, from meeting regulatory standards for groundwater to reducing costs. The report proposes elements of a protocol for accomplishing source remediation that should enable project managers to decide whether and how to pursue source remediation at their sites.

Download or read book Microbiology of the Terrestrial Deep Subsurface written by Penny S. Amy and published by CRC Press. This book was released on 2018-01-10 with total page 368 pages. Available in PDF, EPUB and Kindle. Book excerpt: Obtaining and analyzing samples is challenging in subsurface science. This first-of-its-kind reference book addresses accomplishments in this field-from drilling to sample work-up. A collaborative approach is taken, involving the efforts of microbiologists, geochemists, hydrologists, and drilling and mining experts to present a comprehensive view of subsurface research. The text provides practical information about obtaining, analyzing, and evaluating subsurface materials; the current status of subsurface microbial ecology; and describes several applications that will interest a variety of readers, including engineers, physical, and life scientists.

Download or read book Preliminary Assessment of Microbial Communities and Biodegradation of Chlorinated Volatile Organic Compounds in Wetlands at Cluster 13 Lauderick Creek Area Aberdeen Proving Ground Maryland written by Michelle M. Lorah and published by . This book was released on 2003 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Microbial Diversity in Sediments and Gas Hydrates Associated with Cold Seeps in the Gulf of Mexico written by Heath Jordan Mills and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A molecular phylogenetic approach was used to characterize the composition of microbial communities from two gas hydrate sedimentary systems in the Gulf of Mexico. Nucleic acids were extracted from three distinct locales on surface breaching gas hydrate mounds, i.e., sediment overlaying gas hydrate, sediment/hydrate interface and sediment-free hydrate, and from three sediment depths, i.e., 0-2, 6-8 and 10-12 cm, in Beggiatoa sp. mat-associated sediments located several meters from exposed gas hydrate. Samples were collected from a research submersible (water depth 550-575 m) during two research cruises aboard the R/V Seward Johnson I and II funded by the NSF Life in Extreme Environments program. The 16S rRNA gene and 16S rRNA were amplified using PCR and reverse transcription-PCR, respectively, from DNA and RNA extracted from the total microbial community. The primers targeted microorganisms at the domain-specific, i.e., Bacteria and Archaea, and group-specific, i.e., sulfate-reducing bacteria (SRB) and putative anaerobic methane-oxidizing (ANME) archaea, level. Sequence analysis of the Bacteria clones revealed that the microbial communities were primarily dominated by Deltaproteobacteria. Other Proteobacteria classes, including Epsilon- and Gammaproteobacteria, represented a large fraction of the total microbial community isolated from the sediment overlying hydrate sample and the metabolically active fraction of the 0-2 cm sediment depth sampled from the Beggiatoa sp. mat-associated sediments. Sequence analysis indicated the majority of the archaeal clones were most closely related to Methanosarcinales, Methanomicrobiales and distinct lineages within the ANME groups. Several novel lineages were identified including a fourth ANME-2 clade, i.e., ANME-2D, and three clades with no closely related previously sequenced 16S rRNA gene clones or isolates, i.e., Unclassified Bacteria groups 1 and 2 and Unclassified Euryarchaeota. These studies represent the first 16S rRNA gene and 16S rRNA phylogenetic-based description of microbial communities extant in sediment-free gas hydrate and in methane-rich hydrate-associated and Beggiatoa sp.-associated sediments from a hydrocarbon seep region in the Gulf of Mexico.

Download or read book Vadose Zone Microbial Community Structure and Activity in Metal radionuclide Contaminated Sediments Final Technical Report written by and published by . This book was released on 2002 with total page 11 pages. Available in PDF, EPUB and Kindle. Book excerpt: This final technical report describes the research carried out during the final two months of the no-cost extension ending 11/14/01. The primary goals of the project were (1) to determine the potential for transformation of Cr(VI) (oxidized, mobile) to Cr(III) (reduced, immobile) under unsaturated conditions as a function of different levels and combinations of (a) chromium, (b) nitrate (co-disposed with Cr), and (c) molasses (inexpensive bioremediation substrate), and (2) to determine population structure and activity in experimental treatments by characterization of the microbial community by signature biomarker analysis and by RT-PCR and terminal restriction fragment length polymorphism (T-RFLP) and 16S ribosomal RNA genes. It was determined early in the one-year no-cost extension period that the T-RFLP approach was problematic in regard to providing information on the identities of microorganisms in the samples examined. As a result, it could not provide the detailed information on microbial community structure that was needed to assess the effects of treatments with chromium, nitrate, and/or molasses. Therefore, we decided to obtain the desired information by amplifying (using TR-PCR, with the same primers used for T-RFLP) and cloning 16S rRNA gene sequences from the same RNA extracts that were used for T-RFLP analysis. We also decided to use a restriction enzyme digest procedure (fingerprinting procedure) to place the clones into types. The primary focus of the research carried out during this report period was twofold: (a) to complete the sequencing of the clones, and (b) to analyze the clone sequences phylogenetically in order to determine the relatedness of the bacteria detected in the samples to each other and to previously described genera and species.

Download or read book Microbial Communities in Pristine and Tetrachloroethylene contaminated Aquifer Sediment written by Merry Shannon Riley-Buckley and published by . This book was released on 2001 with total page 428 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Contaminated Sediments written by Jacques Locat and published by ASTM International. This book was released on 2003 with total page 330 pages. Available in PDF, EPUB and Kindle. Book excerpt: The main goal of the May 2003 symposium was to identify both established and innovative physico-chemical and biological methods used to characterize and evaluate properties and behavior of contaminated sediments, as well as the potential for their transfer. Papers from the symposium describe recent

Download or read book Characterization of Bacterial Communities of Riverbank Sediments Contaminated with Polycylcic Aromatic Hydrocarbons written by Gloria Patricia Johnston and published by . This book was released on 2014 with total page 27 pages. Available in PDF, EPUB and Kindle. Book excerpt: Microbial community structure and function are important to ecological processes and to the surrounding physical and chemical environment. Microbes also respond to changes in environmental conditions by oxidizing and transforming pollutants. Sediment contamination is a worldwide problem, yet there is a gap of information about geochemistry and structure of microbial communities in riverbank sediments impacted by long-term pollution. Characterizing the bacterial community in contaminated sediments is critical because it might reveal that some species have adapted to pollution and others can use the xenobiotic as energy and/or carbon sources. We measured high concentrations of polycyclic aromatic hydrocarbons (PAH) in riverbank sediments of the Mahoning River (Ohio, USA) derived from both pyrolytic and petrogenic sources, ranking this sediment as one of the most polluted aquatic ecosystems worldwide. A very high ecological risk to aquatic organisms, even at what was previously considered an unpolluted site was found. Multivariate statistics revealed that bacterial communities followed a temporal and spatial pattern similarly to that found in uncontaminated aquatic environments. PAHs, metals, sulfate, pH, and moisture represented a strong geochemical gradient that likely influenced community composition. Phylogenetic analysis of the 16S rDNA gene revealed groups of bacteria including d-proteobacteria, firmicutes, and bacteriodetes. Some members of these groups have been described as important in PAH degradation. Analysis of the dsrAB gene revealed that most sequences were closely affiliated with unknown, uncultured sulfate reducing bacteria (SRB). Two PAHs were used as models to measure their disappearance over time under sulfate reducing conditions and when a humic acid analogue (anthraquinone-2,6-disulfonate [AQDS]) was added to sediments. After 40-days of anaerobic incubation phenanthrene and fluorene degradation with AQDS was greatly increased in comparison to sediments undergoing natural attenuation. The presence of PAH-degrading and SRB indicated that degradation was likely a biotic mediated process. My research demonstrated that bacterial communities respond to intensive and extensive pollution and are driven by environmental conditions to different extents. In response, microbial communities likely used sulfate and humics for energy and PAHs as carbon sources, contributing to biogeochemical cycling of sulfur and carbon, and providing an important ecosystem function translated as degradation of PAHs.

Download or read book Environmental and Engineering Geology of Northeastern New Jersey written by Matthew L. Gorring and published by . This book was released on 2008 with total page 130 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Contaminated Ground Water and Sediment written by Calvin C. Chien and published by CRC Press. This book was released on 2003-11-24 with total page 288 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is the documented result of an expert workshop, Modeling and Management of Emerging Environmental Issues, held at Penn State University. This event assembled four panels of modeling experts from the U.S. and Canada to discuss modeling technology development and application in order to promote sound and cost-effective environmental decision-making. This thorough analysis provides an overview on the state-of-the-art in current practice and identifies emerging research and development trends within modeling technology. Each of the discussions considers not only technical issues, but regulatory and cost factors as well.

Download or read book Microbial Communities Structure of the Japan Trench Cold seeps Determined by Lipid Analysis written by Wai Olivia Chan and published by . This book was released on 2005 with total page 168 pages. Available in PDF, EPUB and Kindle. Book excerpt: Seafloor cold seeps support some of the most prolific and diverse ecosystems on Earth. A multitude of microbial habitats are associated with cold seeps. The seeping fluids are enriched in reduced chemical species such as sulfide and methane. These reduced species are utilized by microorganisms to gain energy from the reduction of sulfate and oxidation of methane, or the so-called anaerobic oxidation of methane (AOM). The Japan Trench is the deepest seafloor cold seeps found on earth and characterized by abundant chemosynthesis-based communities associated with the cold seeps. Chemosynthetic communities of Maorithyas hadalis and Calyptogena phaseoliformis have been discovered at depth of over 7,000 m. In this project, four sediments samples from chemosynthetic communities dominated by M. hadalis and C. phaseoliformis and two clam tissue (leg and gill) samples of M hadalis were collected. To obtain quantitative information of the Japan Trench cold-seeps, lipid analysis was used to determine the sedimentary microbial community structure of both communities, and to identify the symbionts living inside the Maorithyas hadalis gill tissue. Phospholipid fatty acids, hopanoids, glycolipid fatty acids, sterols and n-alkanes were isolated from the samples and analyzed using gas chromatography/mass Spectrometry (GC/MS). The total microbial biomass were estimated to be 5.71 x 108 and 4.58 x 108 cells (g dry wt)−1 for the Maorithyas and Calyptogena sediments, respectively. The microbial biomarker assemblages of the sediments indicate similar complex consortia of microorganisms were present in both communities, including sulfate-reducing and sulfur-oxidizing bacteria. The lipid profiles isolated from the M hadalis gills contained large amount of monounsaturated (C16:1, C18:1 and C20:1), terminal-branched (iC15:0, aC15:0, iC17:0), cyclopropane (C17: 0cy) and polyunsaturated fatty acids (C18:2, C20:4, C20:5 and C22:2), suggesting the presence of sulfur-oxidizers including Thiomicrospira species as symbiotic bacteria. From these results, I propose a model of the coupled carbon and sulfur cycling within the chemosynthetic communities in the Japan Trench cold-seeps.

Download or read book Microbial Community Analysis from Petroleum contaminated Sediments with High Magnetic Susceptibility written by Anja E. Williams and published by . This book was released on 2015 with total page 80 pages. Available in PDF, EPUB and Kindle. Book excerpt: Microbial biodegradation is an increasingly incorporated method of hydrocarbon mineralization during oil spill cleanup. To monitor biodegradation, magnetic susceptibility is a geophysical tool that detects changes in sediments magnetism, possibly caused by microbial activity, for example by anaerobic iron reduction that can induce magnetite formation. Furthermore, the high input of carbon from an oil spill makes other required nutrients, like nitrogen, limiting. The first study goal was to characterize the microbial communities present at high levels of MS with 16S rRNA gene clone libraries at the petroleum contaminated site in Bemidji, Minnesota. Sequences with high similarity to known iron reducers were found. In addition, sequences with high similarity to the syntrophic Smithella and the Archaeon Methanoregula were found, indicating methanogenic oil degradation. In a different approach, bacteria were isolated from the contaminated soil and identified with 16S rRNA sequencing. The second goal was to characterize nitrogen fixing populations present at the oil plume with nifH clone libraries. Sequences with high similarity to the nifH gene of rhizobia and other microorganisms associated with oil degradation were found. These results suggest that an increase in MS is directive towards active biodegradation, and that nitrogen fixation is performed by microorganisms involved in oil degradation.

Download or read book In Situ Capping of Contaminated Sediments written by David Whims Himmelheber and published by . This book was released on 2007 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Laboratory-scale experiments with capped sediment columns demonstrated that emplacement of a sand-based in situ cap induced an upward, vertical shift of terminal electron accepting processes into the overlying cap while simultaneously conserving redox stratification. Upflow conditions simulating a groundwater seep compressed anaerobic processes towards the cap-water interface. Microorganisms indigenous to the underlying sediment colonized cap material and spatial population differences generally reflected redox stratification. Downflow of oxic surface water through the cap, simulating tidally-induced recharge, created fully oxic conditions within the cap, demonstrating that flow direction strongly contributes to redox conditions. Experiments simulating capped sediment subject to contaminated groundwater seepage revealed a reduction of natural bioattenuation processes with time, stemming from the elimination of labile organic matter deposition to the sediment and a subsequent lack of electron donor. Thus, parent contaminants within groundwater seeps will be subject to minimal biotransformations within the sediment before entering a reducing cap. A bioreactive cap, inoculated with microorganisms capable of reductive dehalogenation, was established to reductively dechlorinate tetrachloroethene present in the groundwater; however electron donor amendments to sediment effluent were required to achieve complete dechlorination of tetrachloroethene to non-toxic ethene. Results from this work improve understanding of biogeochemical and bioattenuation processes within capped aquatic sediments and should aid in the development of active capping technologies.

Download or read book Water resources Investigations Report written by and published by . This book was released on 2003 with total page 360 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Phylogenetic Characterization of Subsurface Sediment Microbial Communities written by Paul A. Vescio and published by . This book was released on 2000 with total page 190 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Selected Water Resources Abstracts written by and published by . This book was released on 1991 with total page 882 pages. Available in PDF, EPUB and Kindle. Book excerpt: