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Full-Text Articles in Physical Sciences and Mathematics

The Influence Of Hydrogen Peroxide On The Enrichment Of Fe(Iii) Reducing Bacteria From Acid Mine Drainage, Susami Seth Jan 2022

The Influence Of Hydrogen Peroxide On The Enrichment Of Fe(Iii) Reducing Bacteria From Acid Mine Drainage, Susami Seth

Williams Honors College, Honors Research Projects

It is hypothesized that the ocean of Europa, a Jupiter moon, hosts bacteria on its oceanic floor. Understanding how Fe(III) reducing bacteria (FeRB) from AMD utilize organic materials within its surrounding environment outlines how FeRB could thrive and tolerate extreme conditions. FeRB are known to tolerate metals and highly reactive oxidants species (ROS), but in this experiment, H2O2 was the experimental factor to further test FeRB tolerance. H2O2 is a common ROS and is damaging to living material such as proteins, DNA, and RNA. A range of H2O2 concentrations were fed …


Microbial Responses To Unconventional Oil And Gas Development May Alter Ecosystem Function In Headwater Streams, Rachel Michaels Jan 2020

Microbial Responses To Unconventional Oil And Gas Development May Alter Ecosystem Function In Headwater Streams, Rachel Michaels

Graduate Theses, Dissertations, and Problem Reports

The demand for natural gas, and the need for efficient extraction, has led to the development of unconventional oil and natural gas (UOG) techniques. Due to the novelty of UOG, the potential impacts to freshwater ecosystems are not fully understood. We used a dual pronged approach to study the effects of UOG development on microbial biodiversity and function via a laboratory microcosm experiment and a survey study of streams with and without UOG development within their watersheds. The laboratory microcosm study simulated stream contamination with produced water, a byproduct of UOG operation, using sediment collected from one high water-quality stream …


The Effects Of Seasonal Variations In Chemistry And Hydrology On The Microbial Community And Its Sulfide Oxidation Potential In A Naturally Acidic Maine Stream, Raymond C. Kahler Iii Dec 2018

The Effects Of Seasonal Variations In Chemistry And Hydrology On The Microbial Community And Its Sulfide Oxidation Potential In A Naturally Acidic Maine Stream, Raymond C. Kahler Iii

Electronic Theses and Dissertations

Sulfide minerals oxidize through interaction with water and oxygen, releasing hydrogen ions. The process often occurs naturally near metal sulfide deposits, and can be accelerated through mining. Microorganisms accelerate the rate of sulfide oxidation. Acidified streams typically contain high metal concentrations (e.g. aluminum) and microbes in these systems may develop resistances to metal toxicity. Stream flow can affect sulfide oxidation and microbial community structure. Baseflow can influence stream chemistry from interactions with the surrounding bedrock, while stormflow affects stream chemistry and the local microbial community through dilution and addition of microbes transported by runoff. Microbial community composition is affected by …


Investigation Of Biogeochemical Mechanisms Of Greenhouse Gas Production In The Urban Hudson River Estuary, Brian Alan Brigham Sep 2018

Investigation Of Biogeochemical Mechanisms Of Greenhouse Gas Production In The Urban Hudson River Estuary, Brian Alan Brigham

Dissertations, Theses, and Capstone Projects

Coastal megacities deposit significant amounts of carbon (C), nitrogen (N) and other pollutants into surrounding waters. These inputs, including wastewater and surface water runoff, may affect estuarine and adjacent wetland biogeochemical cycles, microbial production and ultimately greenhouse gas (GHG) efflux. In many megacities pollutant loading is typically greatest after periods of precipitation when the volume of wastewater and storm water runoff exceeds local sanitation capacity, resulting in the discharge of raw sewage into adjacent waters. These combined sewage overflow (CSO) events have received considerable attention primarily due to their potential impact on human health and eutrophication. However, whether these events …


Elucidating The Impact Of Roseophage On Roseobacter Metabolism And Marine Nutrient Cycles, Nana Yaw Darko Ankrah May 2015

Elucidating The Impact Of Roseophage On Roseobacter Metabolism And Marine Nutrient Cycles, Nana Yaw Darko Ankrah

Doctoral Dissertations

As the most abundant biological entities in marine environments, viruses are an important component of marine food webs. The activity of viruses contributes significantly to the mortality of marine microorganisms, ultimately influencing biological function and chemical composition of aquatic systems by impacting species composition and flow of carbon, nitrogen and other nutrients. Despite the growing recognition that viral activity contributes to marine biogeochemical cycles, the extent to which virus infection reshapes host metabolism and the effect of this alteration on the composition of host lysate remains poorly understood. Additionally, the degree to which natural bacterioplankton communities metabolise the released lysate …


The Influence Of Hydrogeomorphology, Soil Redox Conditions, And Salinity On The Spatial Zoning Of Saltgrass, Salt Rush, And Cattails In Scotts Creek Marsh, Swanton Pacific Ranch, Ca, Mark D. Gormley Dec 2013

The Influence Of Hydrogeomorphology, Soil Redox Conditions, And Salinity On The Spatial Zoning Of Saltgrass, Salt Rush, And Cattails In Scotts Creek Marsh, Swanton Pacific Ranch, Ca, Mark D. Gormley

Master's Theses

Scotts Creek Marsh (SCM) is a small coastal wetland ecosystem in Davenport, CA. The vegetation of SCM is dominated by three halophytic zones comprised of saltgrass, salt rush, cattails. The objectives of the study were (i) to investigate the variables that influence the zoning of the three dominant halophyte communities in SCM and (ii) to the test the effectiveness of Indicator of Reduction in Soil (IRIS) tubes to indicate the reduction of S. The study examined the following parameters from April 6 to July 21, 2013: (i) the HGM of Scotts Creek Marsh, (ii) soil oxidation and reduction (redox) conditions, …