Assessing The Periodic Groundwater Flow Conditions Of A Perched Aquifer System In The Daniel Boone National Forest, 2017 Murray State University
Assessing The Periodic Groundwater Flow Conditions Of A Perched Aquifer System In The Daniel Boone National Forest, Ethan Sweet
Assessing the Periodic Groundwater Flow Conditions of a Perched Aquifer System in the Daniel Boone National Forest
Ethan Sweet and Jonathan Malzone
Eastern Kentucky University, Department of Geosciences
Natural ephemeral wetlands situated among the ridge-tops in the Daniel Boone National Forest serve as reservoirs that recharge a shallow groundwater system. Unique interactions between surface and groundwater in these isolated systems provide substantial support for the native ecosystem, serving as a breeding ground for amphibians and as source water for vegetation—especially in periods of drought. Currently it is not understood how groundwater could provide regional biodiversity, a drought buffer, or ...
The Effects Of Environment On Arctica Islandica Shell Formation And Architecture, 2017 University of Mainz
The Effects Of Environment On Arctica Islandica Shell Formation And Architecture, Stefania Milano, Gernot Nehrke, Alan D. Wanamaker Jr, Irene Ballesta-Artero, Thomas Brey, Bernd R. Schöne
Mollusks record valuable information in their hard parts that reflect ambient environmental conditions. For this reason, shells can serve as excellent archives to reconstruct past climate and environmental variability. However, animal physiology and biomineralization, which are often poorly understood, can make the decoding of environmental signals a challenging task. Many of the routinely used shell-based proxies are sensitive to multiple different environmental and physiological variables. Therefore, the identification and interpretation of individual environmental signals (e.g., water temperature) often is particularly difficult. Additional proxies not influenced by multiple environmental variables or animal physiology would be a great asset in the ...
The Influence Of Temperature And Seawater Carbonate Saturation State On 13c–18o Bond Ordering In Bivalve Mollusks, 2017 University of California, Los Angeles
The Influence Of Temperature And Seawater Carbonate Saturation State On 13c–18o Bond Ordering In Bivalve Mollusks, R. A. Eagle, J. M. Eiler, A. K. Tripati, J. B. Ries, P. S. Freitas, C. Hiebenthal, Alan D. Wanamaker, M. Taviani, M. Elliot, S. Marenssi, K. Nakamura, P. Ramirez, K. Roy
The shells of marine mollusks are widely used archives of past climate and ocean chemistry. Whilst the measurement of mollusk δ18O to develop records of past climate change is a commonly used approach, it has proven challenging to develop reliable independent paleothermometers that can be used to deconvolve the contributions of temperature and fluid composition on molluscan oxygen isotope compositions. Here we investigate the temperature dependence of 13C–18O bond abundance, denoted by the measured parameter Δ47, in shell carbonates of bivalve mollusks and assess its potential to be a useful paleothermometer. We report measurements on cultured specimens spanning a ...
Annually Resolved North Atlantic Marine Climate Over The Last Millennium, 2017 Cardiff University
Annually Resolved North Atlantic Marine Climate Over The Last Millennium, D. J. Reynolds, J. D. Scourse, P. R. Halloran, A. J. Nederbragt, Alan D. Wanamaker, P. G. Butler, C. A. Richardson, J. Heinemeier, J. Eiriksson, K. L. Knudsen, I. R. Hall
Owing to the lack of absolutely dated oceanographic information before the modern instrumental period, there is currently significant debate as to the role played by North Atlantic Ocean dynamics in previous climate transitions (for example, Medieval Climate Anomaly-Little Ice Age, MCA-LIA). Here we present analyses of a millennial-length, annually resolved and absolutely dated marine δ18O archive. We interpret our record of oxygen isotope ratios from the shells of the long-lived marine bivalve Arctica islandica (δ18O-shell), from the North Icelandic shelf, in relation to seawater density variability and demonstrate that solar and volcanic forcing coupled with ocean circulation dynamics are key ...
Oxygen Isotope Ratios In The Shell Of Mytilus Edulis: Archives Of Glacier Meltwater In Greenland?, 2017 University of Reading
Oxygen Isotope Ratios In The Shell Of Mytilus Edulis: Archives Of Glacier Meltwater In Greenland?, E. A. A. Verteegh, M. E. Blicher, J. Mortensen, S. Rysgaard, T. D. Als, Alan D. Wanamaker
Melting of the Greenland Ice Sheet (GrIS) is accelerating and will contribute significantly to global sea level rise during the 21st century. Instrumental data on GrIS melting only cover the last few decades, and proxy data extending our knowledge into the past are vital for validating models predicting the influence of ongoing climate change. We investigated a potential meltwater proxy in Godthåbsfjord (West Greenland), where glacier meltwater causes seasonal excursions with lower oxygen isotope water (δ18Ow) values and salinity. The blue mussel (Mytilus edulis) potentially records these variations, because it precipitates its shell calcite in oxygen isotopic equilibrium with ambient ...
Facilitate Visualization And Distribution Of Nasa's Environmental Science Data Through Open Standards And Open Source Software For Geospatial, 2017 Oak Ridge National Laboratory
Facilitate Visualization And Distribution Of Nasa's Environmental Science Data Through Open Standards And Open Source Software For Geospatial, Yaxing Wei, Zhaoying (Angie) Wei, Suresh Santhanavannan
Free and Open Source Software for Geospatial (FOSS4G) Conference Proceedings
This paper introduces the utilization of open standards and open source software for visualization and distribution of geospatial environmental science data at the Oak Ridge National Laboratory Distributed Active Archive Center (ORNL DAAC). The ORNL DAAC is one of the NASA Earth Observing System Data and Information System (EOSDIS) data centers. A big challenge for the ORNL DAAC (https://daac.ornl.gov) is to efficiently manage over a thousand heterogeneous environmental data, collected through field campaigns, aircraft/satellite observations, and model simulations. ORNL DAAC also has to provide tools to easily find, visualize, and access the heterogeneous data. To address ...
Nitrogen And Carbon Isotopic Dynamics Of Subarctic Soils And Plants In Southern Yukon Territory And Its Implications For Paleoecological And Paleodietary Studies, 2017 The University of Western Ontario
Nitrogen And Carbon Isotopic Dynamics Of Subarctic Soils And Plants In Southern Yukon Territory And Its Implications For Paleoecological And Paleodietary Studies, Farnoush Tahmesabi, Fred J. Longstaffe, Grant Zazula, Bruce Bennett
Earth Sciences Publications
We examine here the carbon and nitrogen isotopic compositions of bulk soils (8 topsoil and 7 subsoils, including two soil profiles) and five different plant parts of 79 C3 plants from two main functional groups: herbs and shrubs/subshrubs, from 18 different locations in grasslands of southern Yukon Territory, Canada (eastern shoreline of Kluane Lake and Whitehorse area). The Kluane Lake region in particular has been identified previously as an analogue for Late Pleistocene eastern Beringia. All topsoils have higher average total nitrogen δ15N and organic carbon δ13C than plants from the same sites with ...
Methylmercury Production In Two Northern Fen Peatlands, 2017 The University of Western Ontario
Methylmercury Production In Two Northern Fen Peatlands, Mikhail J. Mack
Electronic Thesis and Dissertation Repository
Northern peatlands provide conditions favourable for sulphate reducing bacteria, microorganisms responsible for producing methylmercury, an aquatic pollutant. An expected climate driven shift from moss- to sedge-dominance may alter mercury biogeochemistry. Observations from a moss-dominated poor fen and sedge-dominated intermediate fen were used to compare methylmercury to assess if contrasting plant communities, nutrients status and/or hydrologic regime control production. Chapter 2 compared porewater methylmercury and ancillary chemistry across two Northern Ontario fens. The lower water table, greater dissolved organic carbon, and lower pH in the poor fen resulted in 3.1 times greater methylmercury. Chapter 3, riparian zones in intermediate ...
Xzlamalraab_Clorg (2017).Pdf, 2017 San Diego State University
Xzlamalraab_Clorg (2017).Pdf, Jaime Zlamal, Ted K. Raab, Robert A. Edwards, Mark Little, David A. Lipson
Ted K. Raab
Influence Of Common Bean (Phaseolus Vulgaris) Grown In Elevated Co2 On Apatite Dissolution, 2017 University of Maine
Influence Of Common Bean (Phaseolus Vulgaris) Grown In Elevated Co2 On Apatite Dissolution, Brian Matthew Morra
Electronic Theses and Dissertations
Elevated concentrations of atmospheric CO2 brought about by human activity creates changes in plant morphology, growth rate and exudate production. Our study sought to understand the effect of these changes on soil mineral weathering using plants grown under two conditions, ambient CO2 (400ppm) and elevated CO2 (1000ppm). Phaseolus vulgaris (common beans) were grown in flow-through microcosms consisting of a mixture of quartz and apatite sands. Plant growth was sustained by a nutrient solution devoid of calcium (Ca) and phosphorous (P). Using Atomic Adsorption Spectroscopy and colorimetry, Ca and P content of the leachate and plant tissue served ...
The Effects Of Urbanization On Nitrogen Processing In Urban Streams, 2017 Augustana College, Rock Island Illinois
The Effects Of Urbanization On Nitrogen Processing In Urban Streams, Peter Francissen, Dr. Kevin Geedey, Dr. Michael Reisner
Celebration of Learning
Urban stream syndrome is described as the deterioration of stream health in an urbanized watershed and is associated with the loss of ecosystem services, which in turn degrades downstream environments. One key symptom of the urban stream syndrome is reduced processing of inorganic nitrogen. Previous research suggests that as urbanization increases and water quality decreases, the uptake length (Sw) of inorganic N increases. This indicates that the stream is increasing the export of N downstream compared to in situ incorporation of N into the ecosystem. We measured uptake length (Sw) of NO3, using a pulse addition method, along 9 different ...
Summer Precipitation Occurrence Effect On Two Passerine Species In Thule, Greenland, 2017 Augustana College, Rock Island Illinois
Summer Precipitation Occurrence Effect On Two Passerine Species In Thule, Greenland, Sara E. Baugh
Celebration of Learning
Climate change is occurring at a faster rate in the Arctic than the rest of the globe, causing temperature rises at twice the rate of the global average and increased summer precipitation in the form of rain. These precipitation events are predicted to affect migratory bird species that breed throughout the Arctic. Increased occurrence of heavy rainstorms indirectly affect bird populations by impacting distribution and abundance of food supply, and directly by increasing mortality rates of juveniles. Studies conducted on bird species throughout the low Arctic regions; have shown that it is not the total precipitation of a breeding season ...
Determining Sources Of Nitrate In The Semi-Arid Rio Grande Using Nitrogen And Oxygen Isotopes, 2017 University of Tennessee, Knoxville
Determining Sources Of Nitrate In The Semi-Arid Rio Grande Using Nitrogen And Oxygen Isotopes, Diego Alberto Sanchez Hernandez
The Rio Grande, a semi-arid river in the American Southwest, is a major source of surface water for agriculture and drinking supplies in New Mexico and Texas. In addition to increasing salinity, considerable increases of NO3- [nitrate] have been observed in the semi-arid portion of the Rio Grande. It is possible that elevated water salinity inhibits denitrification on irrigated fields and, thus, fails to mediate excess nutrient load from anthropogenic activities. Therefore, two major goals of this project were to 1) characterize and quantify major NO3- sources, and 2) assess whether elevated water salinity affects microbial denitrification. In ...
Influence Of Algae On Soil Saturated Hydraulic Conductivity: An In Situ Treatment Option For Reducing Infiltration Beneath Unlined Algae Cultivation Ponds, 2017 University of Tennessee, Knoxville
Influence Of Algae On Soil Saturated Hydraulic Conductivity: An In Situ Treatment Option For Reducing Infiltration Beneath Unlined Algae Cultivation Ponds, Molly Brianne Pattullo
Commercial production of algal biofuels is currently limited by high capital costs, including the cost of installation and maintenance of plastic pond liners, which mitigate seepage of cultivation fluids and control the release of salts and nutrients into the subsurface beneath outdoor algae cultivation ponds. However, studies of animal waste settling lagoons show that underlying soils ranging from sands to clay loams can exhibit reduced hydraulic conductivity within days to weeks after construction, reducing the need for plastic liners. The mechanisms of the hydraulic conductivity reductions, or “soil sealing”, are physical rearrangement of soil particles, buildup of fines, and the ...
Catalyzed Synthesis Of Zinc Clays By Prebiotic Central Metabolites, 2017 University of Kentucky
Catalyzed Synthesis Of Zinc Clays By Prebiotic Central Metabolites, Marcelo I. Guzman, Ruixin Zhou, Kaustuv Basu, Hyman Hartman, Christopher J. Matocha, S. Kelly Sears, Hajatollah Vali
Chemistry Faculty Publications
How primordial metabolic networks such as the reverse tricarboxylic acid (rTCA) cycle and clay mineral catalysts coevolved remains a mystery in the puzzle to understand the origin of life. While prebiotic reactions from the rTCA cycle were accomplished via photochemistry on semiconductor minerals, the synthesis of clays was demonstrated at low temperature and ambient pressure catalyzed by oxalate. Herein, the crystallization of clay minerals is catalyzed by succinate, an example of a photoproduced intermediate from central metabolism. The experiments connect the synthesis of sauconite, a model for clay minerals, to prebiotic photochemistry. We report the temperature, pH, and concentration dependence ...
A Model Archive For A Coupled Hydrodynamic-Sediment Transport-Biogeochemistry Model For The Rhône River Sub-Aqueous Delta, France, 2017 College of William and Mary
A Model Archive For A Coupled Hydrodynamic-Sediment Transport-Biogeochemistry Model For The Rhône River Sub-Aqueous Delta, France, Julia Moriarty, Courtney K. Harris, Katja Fennel, Kehui Xu, Christophe Rabouille, Marjorie A.M. Friedrichs
This dataset includes model input, code, and output used in the publication Moriarty et al. (2017, Biogeosciences), which used a coupled hydrodynamic-sediment transport-biogeochemical model to investigate the roles of resuspension, diffusion and biogeochemical processes on oxygen dynamics on the Rhône River sub-aqueous delta, France. Model development for this project focused on coupling the sediment transport and water-column biogeochemistry modules in the Regional Ocean Modeling System (ROMS) by incorporating a seabed biogeochemistry module into the ROMS framework. As described in Moriarty et al. (2017, Biogeosciences), the coupled model can account for diffusion of nutrients across the seabed-water-column interface; storage of particulate ...
Multiple Metabolisms Constrain The Anaerobic Nitrite Budget In The Eastern Tropical South Pacific, 2017 Old Dominion University
Multiple Metabolisms Constrain The Anaerobic Nitrite Budget In The Eastern Tropical South Pacific, Andrew R. Babbin, Brian D. Peters, Calvin W. Mordy, Brittany Widner, Karen L. Casciotti, Bess B. Ward
OEAS Faculty Publications
The Eastern Tropical South Pacific is one of the three major oxygen deficient zones (ODZs) in the global ocean and is responsible for approximately one third of marine water column nitrogen loss. It is the best studied of the ODZs and, like the others, features a broad nitrite maximum across the low oxygen layer. How the microbial processes that produce and consume nitrite in anoxic waters interact to sustain this feature is unknown. Here we used 15N-tracer experiments to disentangle five of the biologically mediated processes that control the nitrite pool, including a high-resolution profile of nitrogen loss rates ...
Assessing The Potential To Decrease The Gulf Of Mexico Hypoxic Zone With Midwest Us Perennial Cellulosic Feedstock Production, Andy Vanloocke, Tracy E. Twine, Christopher J. Kucharik, Carl J. Bernacchi
The goal of this research was to determine the changes in streamflow, dissolved inorganic nitrogen (DIN) leaching and export to the Gulf of Mexico associated with a range of large-scale dedicated perennial cellulosic bioenergy production scenarios within in the Mississippi–Atchafalaya River Basin (MARB). To achieve this goal, we used Agro-IBIS, a vegetation model capable of simulating the biogeochemistry of row crops, miscanthus and switchgrass, coupled with THMB, a hydrology model capable of simulating streamflow and DIN export. Simulations were conducted at varying fertilizer application rates (0–200 kg N ha -1) and fractional replacement (5–25%) of current row ...
Candidate Perennial Bioenergy Grasses Have A Higher Albedo Than Annual Row Crops, 2017 University of Illinois at Urbana-Champaign
Candidate Perennial Bioenergy Grasses Have A Higher Albedo Than Annual Row Crops, Jesse N. Miller, Andy Vanloocke, Nuria Gomez-Casanovas, Carl J. Bernacchi
The production of perennial cellulosic feedstocks for bioenergy presents the potential to diversify regional economies and the national energy supply, while also serving as climate ‘regulators’ due to a number of biogeochemical and biogeophysical differences relative to row crops. Numerous observational and model-based approaches have investigated biogeochemical trade-offs, such as increased carbon sequestration and increased water use, associated with growing cellulosic feedstocks. A less understood aspect is the biogeophysical changes associated with the difference in albedo (a), which could alter the local energy balance and cause local to regional cooling several times larger than that associated with offsetting carbon. Here ...
Analysis Of Microbial Diversity In Disturbed Soil, 2017 University of Akron
Analysis Of Microbial Diversity In Disturbed Soil, Tyler G. Sanda
Honors Research Projects
This paper uses the composition and abundance of microbial species to analyze soil recovery in disturbed land. Surface mining disturbs ecological communities throughout the world. As organizations seek to reclaim these disturbed lands, a proper analysis of recovery is needed. In previous studies, recovery of disturbed land was limited to surface examinations, which do not characterize the possible unseen devastating effects of the subsoil. Soil microorganisms are extremely sensitive to environmental changes such as strip mining. It is proposed that these microorganisms may serve as better indicators of recovery post disturbance. Our analysis indicates microbial recovery, however it may not ...