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Cone In Cone Concretions Of The Stanley Group In Southeastern Oklahoma, Kyle B. Ayres 2016 Stephen F Austin State University

Cone In Cone Concretions Of The Stanley Group In Southeastern Oklahoma, Kyle B. Ayres

Electronic Theses and Dissertations

Cone in cone concretions found in the Stanley Group of Southeastern Oklahoma have a variety of external and internal attributes which allow diagenetic and theoretical models of formation to be hypothesized. Stanley Group carbonate cone in cone concretions are initially formed in sulfur reducing horizons at shallow burial depths in a poorly circulated possibly deep trough containing siliceous sediments and organic matter. Collected concretions near the town of Smithville, Oklahoma displayed four different external morphologies and four variations of mineral constituents. All concretions contained microscopic cones which initiated diffusion and/or fluid patterns and is an early cementation process that ...


Gone With The Wind: Soil Moisture Effects On Gaseous Nitrogen Removal From Wastewater, Faith L. Anderson 2016 University of Rhode Island

Gone With The Wind: Soil Moisture Effects On Gaseous Nitrogen Removal From Wastewater, Faith L. Anderson

Senior Honors Projects

Onsite wastewater treatment systems (OWTS), or septic systems, release nitrogen (N), which can be detrimental to aquatic ecosystems. The final step in the treatment of wastewater is dispersal onto a drainfield, where it percolates through the soil. Part of the N is removed from wastewater and released into the atmosphere as N2 and N2O by denitrification, which requires anoxic conditions. Previous studies looking at the effect of soil water-filled pore space (WFPS) on denitrification using clean water with a high level of dissolved O2 (DO) have identified a minimum of 60% WFPS for denitrification to take ...


Iron Concretions In The Cretaceous Dakota Formation, Anthony Kohtz, Richard Kettler, David Loope 2016 University of Nebraska-Lincoln

Iron Concretions In The Cretaceous Dakota Formation, Anthony Kohtz, Richard Kettler, David Loope

UCARE Research Products

The Cretaceous Dakota Formation contains abundant iron oxide concretions. The precursors to the iron concretions are siderite (FeCO3) nodules that formed in a reducing floodplain environment. A variety of concretion morphologies formed when the precursor siderite nodules were dissolved by oxidizing groundwater in a paleoaquifer. Iron-oxidizing bacteria are able to oxidize aqueous Fe(II) to Fe(III) oxy-hydroxide at microaerophilic and neutrophilic conditions. This study investigated these concretions to determine if there was a microbial element in their formation and to characterize the concretion morphologies present in the Dakota. This is important for complete paleoenvironment interpretations and astrobiology pursuits.


Effects Of Epichloë Coenophiala−Tall Fescue Symbiosis On Plant-Microbe-Soil Interactions In A Temperate Pasture, Lindsey C. Slaughter 2016 University of Kentucky

Effects Of Epichloë Coenophiala−Tall Fescue Symbiosis On Plant-Microbe-Soil Interactions In A Temperate Pasture, Lindsey C. Slaughter

Theses and Dissertations--Plant and Soil Sciences

Plants interact in myriad ways with microorganisms to influence ecosystem processes such as nutrient cycling, which can regulate ecosystem response to global change. One important plant-microbe symbiosis occurs between cool-season grasses and asexual fungal Epichloë endophytes, such as tall fescue (Schedonorus arundinaceus) and Epichloë coenophiala. Because the common toxic strain of the endophyte (CTE) harms grazing livestock, non-livestock toxic endophyte (NTE) strains have been developed and are increasingly deployed in pastures. Little is known about how these symbioses impact other plant-microbe interactions and microbe-mediated soil processes in grassland ecosystems. I conducted three studies to determine how E. coenophiala presence (+) or ...


Evaluating The Biogeochemical Functioning Of A Constructed Fen On The Post-Mining Landscape Of Athabasca Oil Sands Region, Fort Mcmurray, Alberta, Canada, Felix C. Nwaishi 2016 Wilfrid Laurier University

Evaluating The Biogeochemical Functioning Of A Constructed Fen On The Post-Mining Landscape Of Athabasca Oil Sands Region, Fort Mcmurray, Alberta, Canada, Felix C. Nwaishi

Theses and Dissertations (Comprehensive)

Peatlands have a unique biogeochemical function, characterized by an imbalance between the rates of biomass accumulation and decomposition. These characteristics facilitate the ability of peatlands to support the sequestration of nutrients and carbon. In disturbed peatlands, these functions are compromised. Thus, reclamation targets amongst other key functions, the recovery of biogeochemical functioning. These functions could serve as a measure of recovery to conditions that are present in natural analogues. This thesis examines the recovery of microbially-mediated nutrient transformation processes in a fen peatland that was constructed on a post-mining landscape in the Athabasca oil sands region, Fort McMurray, Alberta. The ...


A Shift In Louisiana Salt Marsh Microbial Communities Reflecting Changes In Salinity And Biogeochemical Parameters, Haley Holladay 2016 University of Colorado, Boulder

A Shift In Louisiana Salt Marsh Microbial Communities Reflecting Changes In Salinity And Biogeochemical Parameters, Haley Holladay

Undergraduate Honors Theses

The relationship between microbial communities, salinity, soil depth, and time was evaluated using phospholipid fatty acids (PLFA) collected from coastal wetlands in Louisiana post hurricanes Katrina and Rita. The three marsh types studied included freshwater and intermediate marshes from the Jean Lafitte Preserve as well as two brackish marsh sites from the Caernarvon Basin. The Caernarvon Basin was heavily impacted from the hurricanes leaving the lower sites sampled remnant marsh. The goal of this study was to examine microbial community changes along a salinity gradient to further understand the impact of salinity on the wetland ecosystem. This was done using ...


Surface Chlorophyll Variability In The Drake Passage Region Of The Southern Ocean, Joseph C. Gradone 2016 University of Colorado, Boulder

Surface Chlorophyll Variability In The Drake Passage Region Of The Southern Ocean, Joseph C. Gradone

Undergraduate Honors Theses

The Southern Ocean, the ocean surrounding the Antarctic continent, supports a diverse array of biological species and unique food webs. Given the important role of phytoplankton in Southern Ocean food webs and their influence on the global carbon reservoir, it is of interest to know whether their abundance has changed over time. Chlorophyll is a pigment present in all photosynthesizing phytoplankton that can be used to estimate the biomass and productivity of phytoplankton at a given time and location. This study analyzes surface chlorophyll variability in the Drake Passage region of the Southern Ocean using underway fluorometer derived chlorophyll from ...


Perchlorate Variations Over 300 Years: Influence Of Human Activities, Volcanic Eruptions And Bolide Events, Kari Peterson 2016 South Dakota State University

Perchlorate Variations Over 300 Years: Influence Of Human Activities, Volcanic Eruptions And Bolide Events, Kari Peterson

Theses and Dissertations

Perchlorate, which derives from both anthropogenic and natural sources in the current environment, constitutes a significant health risk to humans because it competitively inhibits iodine uptake by the thyroid gland. Thus, there has been considerable interest in reducing the human exposure to environmental perchlorate by limiting the release of perchlorate from anthropogenic sources. However, a lack of understanding of the relative contributions from anthropogenic and natural sources has prevented widespread regulation. A 300-year ice core perchlorate record from Summit Station, Greenland (1700-2007 C.E.) that extends beyond the onset of the Industrial Revolution (1850 C.E.) is used to assess ...


Gaseous Carbon Emissions (Methane And Carbon Dioxide) From Wetland Soils In A Re-Created Everglades Landscape, Bradley R. Schonhoff 2015 Florida International University

Gaseous Carbon Emissions (Methane And Carbon Dioxide) From Wetland Soils In A Re-Created Everglades Landscape, Bradley R. Schonhoff

FIU Electronic Theses and Dissertations

Reducing the rates of greenhouse gas (GHG) emissions is critical in combatting global climate change. Carbon dioxide (CO2) and methane (CH4) are the two most important carbon-based GHGs, for their atmospheric warming potential. Wetlands such as the Florida Everglades play major roles in the global carbon cycle, as varying hydrologic conditions lead to differential production rates of these two GHGs. This study measured CO2 and CH4 emissions in a re-created Everglades ridge-and-slough wetland, where water levels were controlled to reflect natural flood patterns. As expected, lower elevations were flooded longer and produced more CH4, while ...


In Situ Studies Of Limestone Dissolution In A Coastal Submarine Spring, Rachel Marie Schweers 2015 University of South Florida

In Situ Studies Of Limestone Dissolution In A Coastal Submarine Spring, Rachel Marie Schweers

Graduate Theses and Dissertations

Limestone dissolution in karst environments is likely due to geochemistry of the water, the actions of microbial communities, and the effect of water flow. We explored the rate of

limestone dissolution and will examine here the microbial communities associated with the limestone. A conduit within the brackish cave, Double Keyhole Spring, on the coast of central west Florida was the site of the experiment. PVC pipes (5cm x 16cm) were filled with crushed limestone that was screened to a 1.9cm – 2.54cm size range. There were three treatments (5 replicates each): Control - sealed autoclaved controls with limestone and conduit ...


Source-Specific Molecular Signatures For Light-Absorbing Organic Aerosols, Amanda Susan Willoughby 2015 Old Dominion University

Source-Specific Molecular Signatures For Light-Absorbing Organic Aerosols, Amanda Susan Willoughby

Chemistry & Biochemistry Theses & Dissertations

Organic aerosols (OA) are universally regarded as an important component of the atmosphere based on quantitative significance as well as the far-reaching impact they have on global climate forcing and human health. Despite the acknowledged importance, OA amounts and impacts remain the largest uncertainties regarding radiative forcing estimates. Incomplete chemical characterization of aerosol organic matter (OM) and a lack of concrete source apportionment is a major source of this uncertainty. The primary focus of this study is to provide much needed molecular details regarding ambient OA from key emission sources, and establish links between molecular and optical properties.

Complete chemical ...


Disentangling Climatic And Anthropogenic Controls On Global Terrestrial Evapotranspiration Trends, Jiafu Mao, Wenting Fu, Xiaoying Shi, Daniel Ricciuto, Joshua Fisher, Robert Dickinson, Yaxing Wei, Willis Shem, Shilong Piao, Kaicun Wang, Christopher Schwalm, Hanqin Tian, Mingquan Mu, Altaf Arain, Philippe Ciais, Robert Cook, Yongdiu Dai, Daniel Hayes, Forrest Hoffman, Maoyi Huang, Suo Huang, Deborah Huntzinger, Akihiko Ito, Atul Jain, Anthony King, Huimin Lei, Chaoqun Lu, Huimin Lei, Anna Michalak, Changhui Peng, Shushi Peng, Benjamin Poulter, Kevin Schaefer, Elshin Jafarov, Peter Thornton, Weile Wang, Ning Zeng, Zhenzhong Zeng, Fang Zhao, Qiuan Zhu, Zaichun Zhu 2015 Oak Ridge National Laboratory

Disentangling Climatic And Anthropogenic Controls On Global Terrestrial Evapotranspiration Trends, Jiafu Mao, Wenting Fu, Xiaoying Shi, Daniel Ricciuto, Joshua Fisher, Robert Dickinson, Yaxing Wei, Willis Shem, Shilong Piao, Kaicun Wang, Christopher Schwalm, Hanqin Tian, Mingquan Mu, Altaf Arain, Philippe Ciais, Robert Cook, Yongdiu Dai, Daniel Hayes, Forrest Hoffman, Maoyi Huang, Suo Huang, Deborah Huntzinger, Akihiko Ito, Atul Jain, Anthony King, Huimin Lei, Chaoqun Lu, Huimin Lei, Anna Michalak, Changhui Peng, Shushi Peng, Benjamin Poulter, Kevin Schaefer, Elshin Jafarov, Peter Thornton, Weile Wang, Ning Zeng, Zhenzhong Zeng, Fang Zhao, Qiuan Zhu, Zaichun Zhu

Chaoqun (Crystal) Lu

We examined natural and anthropogenic controls on terrestrial evapotranspiration (ET) changes from 1982 to 2010 using multiple estimates from remote sensing-based datasets and process-oriented land surface models.A significant increasing trend of ET in each hemisphere was consistently revealed by observationally-constrained data and multi-model ensembles that considered historic natural and anthropogenic drivers. The climate impacts were simulated to determine the spatiotemporal variations in ET. Globally, risingCO2 ranked second in these models after the predominant climatic influences, and yielded decreasing trends in canopy transpiration and ET, especially for tropical forests and high-latitude shrub land. Increasing nitrogen deposition slightly amplified global ET ...


Environmental Forcing Does Not Induce Diel Or Synoptic Variation In The Carbon Isotope Content Of Forest Soil Respiration, Steven Hall, D. R. Bowling, J. E. Egan 2015 University of Utah

Environmental Forcing Does Not Induce Diel Or Synoptic Variation In The Carbon Isotope Content Of Forest Soil Respiration, Steven Hall, D. R. Bowling, J. E. Egan

Steven J. Hall

Recent studies have examined temporal fluctuations in the amount and carbon isotope content (δ13C) of CO2 produced by the respiration of roots and soil organisms. These changes have been correlated with diel cycles of environmental forcing (e.g., sunlight and soil temperature) and with synoptic-scale atmospheric motion (e.g., rain events and pressure-induced ventilation). We used an extensive suite of measurements to examine soil respiration over 2 months in a subalpine forest in Colorado, USA (the Niwot Ridge AmeriFlux forest). Observations included automated measurements of CO2 and δ13C of CO2 in the soil efflux, the soil gas profile, and forest ...


Soil Chemistry On Watershed 1: 1998 - 2014, Chris E. Johnson 2015 cejohns@syr.edu

Soil Chemistry On Watershed 1: 1998 - 2014, Chris E. Johnson

Civil and Environmental Engineering

No abstract provided.


Stable Isotopes Of Hydrothermal Carbonate Minerals In The Butte Porphyry-Lode Deposits, Montana, Ryan Stevenson 2015 Montana Tech of the University of Montana

Stable Isotopes Of Hydrothermal Carbonate Minerals In The Butte Porphyry-Lode Deposits, Montana, Ryan Stevenson

Graduate Theses & Non-Theses

The stable isotopic compositions of over 90 hydrothermal carbonate minerals in the Butte porphyry-lode system were analyzed. These samples came from the underground workings as well as the active Continental Pit area. Most material came from polymetallic “Main Stage” veins which post-date the porphyry Cu-Mo mineralization of Butte. Some samples from late calcite-stellerite veins were also included in the study. Rhodochrosite d13C and d18O values range from -8.3 to -2.9‰ (average of -6.7±1.0‰) and -1.8 to 12.8‰ (average of 3.6 ±3.4‰) respectively, while calcite d13C ...


Soil Chemistry On Watershed 1: 1998 - 2014, Chris Johnson 2015 cejohns@syr.edu

Soil Chemistry On Watershed 1: 1998 - 2014, Chris Johnson

Chris E Johnson

No abstract provided.


Record Of Archaeal Activity At The Serpentinite-Hosted Lost City Hydrothermal Field, S. Méhay, G. Früh-Green, Susan Lang, S. Bernasconi, W. Brazelton, M. Schrenk, P. Schaeffer, P. Adam 2015 University of South Carolina - Columbia

Record Of Archaeal Activity At The Serpentinite-Hosted Lost City Hydrothermal Field, S. Méhay, G. Früh-Green, Susan Lang, S. Bernasconi, W. Brazelton, M. Schrenk, P. Schaeffer, P. Adam

Susan Q. Lang

No abstract provided.


H2/Ch4 Ratios Cannot Reliably Distinguish Abiotic Vs. Biotic Methane In Natural Hydrothermal Systems, Susan Lang, G. Früh-Green, D. Kelley, M. Lilley, G. Proskurowski, E. Reeves 2015 University of South Carolina - Columbia

H2/Ch4 Ratios Cannot Reliably Distinguish Abiotic Vs. Biotic Methane In Natural Hydrothermal Systems, Susan Lang, G. Früh-Green, D. Kelley, M. Lilley, G. Proskurowski, E. Reeves

Susan Q. Lang

No abstract provided.


Sources Of Organic Nitrogen At The Serpentinite-Hosted Lost City Hydrothermal Field, Susan Lang, G. Früh-Green, S. Bernasconi, D. Butterfield 2015 University of South Carolina - Columbia

Sources Of Organic Nitrogen At The Serpentinite-Hosted Lost City Hydrothermal Field, Susan Lang, G. Früh-Green, S. Bernasconi, D. Butterfield

Susan Q. Lang

No abstract provided.


Black Carbon: Sources, Mobility And Fate In Freshwater Systems, Sasha Wagner 2015 Florida International University

Black Carbon: Sources, Mobility And Fate In Freshwater Systems, Sasha Wagner

FIU Electronic Theses and Dissertations

Black carbon (BC) is a complex mixture of polycondensed aromatic compounds produced by the incomplete combustion of biomass during events such as wildfires and the burning of fossil fuels. Black carbon was initially considered to be a refractory form of organic matter. However, recent studies have shown that BC can be quite mobile and reactive in the terrestrial environment. Black carbon can be translocated from soils and sediments in the form of dissolved BC (DBC). A global correlation between DBC and bulk dissolved organic carbon (DOC) has been established for fluvial systems where DBC comprises approximately 10% of the total ...


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