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Oxygen Isotope Composition Of Phosphate Along Vertical Weathering Profiles That Developed On Igneous Rocks: Testing Modern Analogues For Identifying Terrestrial Life In Ancient Paleosols, Dustin Warn Boyd

LSU Master's Theses

Life on Earth began in its early oceans before moving on to land. Determining the exact timing of an established biosphere on land, however, has been elusive, due largely to the lack of either fossil or chemical evidence on land deposits. Here I test a hypothesis that the activity of land biota can be recorded in the oxygen isotope composition of phosphate in weathering profiles developed on igneous parent rocks. Igneous rock contains phosphate (PO₄^3-), which is readily utilized for biological activities during soil development. The oxygen in PO₄^3- does not readily exchange its oxygen …

Bramatherium (Artiodactyla, Ruminantia, Giraffidae) From The Middle Siwaliks Of Hasnot, Pakistan: Biostratigraphy And Palaeoecology, Muhammad Akbar Khan, Muhammad Akhtar, Ammara Irum

Turkish Journal of Earth Sciences

We describe here new remains of the giraffid Bramatherium, from the late Miocene-early Pliocene of Hasnot, northern Pakistan. The fossil giraffid material from Hasnot represents 2 taxa of Bramatherium, B. megacephalum and B. grande. The Hasnot locality is characterised by high proportions of ruminants, namely Boselaphini, Antilopini, Sivatheriinae, Cervini, Dorcatherium, and Dorcabune. The Hasnot fossil ruminant assemblage is fairly typical for the Siwalik province and comparisons with the Greco-Iranian-Afghan and African palaeobiological provinces indicate a late Miocene-early Pliocene age. It is suggested that local Hasnot palaeoenvironments comprised wetlands to woodland biomes, perhaps devoid of expansive dense forests.

The Response Of Lake Pontchartrain Fish Assemblages To Hurricanes Katrina And Rita, Martin T. O'Connell, Ann M.U. O'Connell, Christopher Schieble

Earth and Environmental Sciences Faculty Publications

To assess possible impacts on Lake Pontchartrain fishes from the 2005 hurricanes, we 45 compared trawl, beach seine, and gillnet collections taken before (2000-2003, 2005) and after 46 (2006-2009) to determine if significant assemblage changes occurred. We also compared basic 47 environmental variables to test for hurricane-related changes. Significant post-hurricane changes 48 in fish assemblages occurred in trawl (ANOSIM, R < 0.090, p < 0.05) and beach seine 49 (ANOSIM, R < 0.120, p < 0.05) collections across all seasons. Gillnet assemblages exhibited 50 changes in only one season (ANOSIM, R = 0.045, p < 0.05). These consistently low global R 51 values (all R < 0.120) across all gears suggest only minor compositional changes in species. 52 When peak abundance periods were compared for individual species, Gulf menhaden 53 (Brevoortia patronus) declined in trawl collections after the hurricanes (Friedman’s test, χ2 = 54 6.00, p = 0.014) but increased in gillnet collections (Friedman’s test, χ2=5.00, p = 0.025). 55 Hardhead catfish (Ariopsis felis) increased in trawl collections, but Gulf pipefish (Syngnathus 56 scovelli), naked gobies (Gobiosoma bosc), and rough silverside (Membras martinica) all 57 declined in beach seine samples and Atlantic croakers (M. undulatus), Spanish mackerel 58 (Scomberomorus maculatus), and sand seatrout (Cynoscion arenarius) all declined in gillnet 59 samples. In general, salinity increased and water clarity and dissolved oxygen decreased after 60 the hurricanes. While the overall composition of Lake Pontchartrain fish assemblages remains 61 stable, the significant decline of some species and changes in certain environmental variables are 62 cause for concern. Future monitoring should determine if all elements of this estuary will 63 recover from these impacts.

Comparison Of Instrumentation To Measure Air And Soil-Surface Temperature Variability In Northern Alaska, Katrina Keleher

Undergraduate Theses, Professional Papers, and Capstone Artifacts

The Circumpolar Active Layer Monitoring (CALM) project has been observing permafrost (perennially frozen ground) and its overlaying active layer (which freezes and thaws annually) in northern Alaska’s Kuparuk River watershed and throughout the polar regions since the mid 1990’s to detect long-term responses to climatic change. The soil-surface temperature data is collected by thermistors that were positioned immediately below the surface of the ground at nine locations within a transect of 1-ha plots arranged from north to south across the region. Locations within each plot were individually selected to represent a full range of microsite conditions, with distinctions in vegetation, …

Biogeochemistry Of Sulfur Isotopes In Crystal Lake, Clark County, West-Central Ohio, Amanda Lynn Meyer

Browse all Theses and Dissertations

Crystal Lake showed distinct biogeochemical patterns, which were governed by thermal stratification, photosynthesis, and sulfur redox processes. Field parameter measurements and water and Planktothrix rubescens samples were collected in May, August, and October, 2013 at the deepest point in the lake, to better understand these processes. At the metalimnion-hypolimnion boundary, P. rubescens produced chlorophyll and turbidity maxima. Photosynthesis produced oxygen-rich and nutrient-poor surface waters. The decay of organic matter produced anoxic, nutrient-rich water in the hypolimnion. Sulfate concentrations were high in the epilimnion and metalimnion, with a maximum at the layer of P. rubescens, and decreased with depth in the …

Mercury Distributions And Cycling In The North Atlantic And Eastern Tropical Pacific Oceans, Katlin L. Bowman

Browse all Theses and Dissertations

The distribution of mercury (Hg) in the ocean is complex as a result of in situ chemical transformations and inputs from natural and anthropogenic sources. Within the ocean, inorganic Hg is methylated to monomethylmercury (MMHg), which bioaccumulates and biomagnifies in marine food webs and poses a health risk to humans who eat fish. The biogeochemistry of Hg in the ocean has been studied for decades, however, recently improved sampling and analytical techniques have allowed for an enhanced understanding of global distributions of different Hg species. This dissertation uses a newly developed method for the analysis of MMHg that improves detection …

The Emerging Field Of Geogenomics: Constraining Geological Problems With Genetic Data, Paul A. Baker, Sherilyn C. Fritz, Christopher W. Dick, Andrew J. Eckert, Brian K. Horton, Stefano Manzoni, Camila C. Ribas, Carmala N. Garzione, David S. Battisti

Department of Earth and Atmospheric Sciences: Faculty Publications

The development of a genomics-derived discipline within geology is timely, as a result of major advances in acquiring and processing geologically relevant genetic data. This paper articulates the emerging field of “geogenomics,” which involves the use of large-scale genetic data to constrain geological hypotheses. The paper introduces geogenomics and discusses how hypotheses can be ad-dressed through collaboration between geologists and evolutionary biologists. As an example, geogenomic methods are applied to evaluate competing hypotheses regarding the timing of the Andean uplift, the closure of the Isthmus of Panama, the onset of trans-Amazon drainage, and Quaternary climate variation in the Neotropics.

Maintaining Resilience In The Face Of Climate Change, Alejandro E. Camacho, T. Douglas Beard

United States Geological Survey: Staff Publications

Climate change, when combined with more conventional stress from human exploitation, calls into question the capacity of both existing ecological communities and resource management institutions to experience disturbances while substantially retaining their same functions and identities (Zellmer and Gunderson 2009; Ruhl 2011). In other words, the physical and biological effects of climate change raise fundamental challenges to the resilience of natural ecosystems (Gunderson and Holling 2002). Perhaps more importantly, the projected scope of ecological shifts from global climate change-and uncertainty about such changes-significantly stresses the capacity of legal institutions to manage ecosystem change (Camacho 2009). Existing governmental institutions lack the …

Humic Substances Interfere With Detection Of Pathogenic Prion Protein, Christen B. Smith, Clarissa J. Booth, Tyler J. Wadzinski, Giuseppe Legname, Rick Chappell, Christopher J. Johnson, Joel A. Pedersen

United States Geological Survey: Staff Publications

Studies examining the persistence of prions (the etiological agent of transmissible spongiform encephalopathies) in soil require accurate quantification of pathogenic prion protein (PrPTSE) extracted from or in the presence of soil particles. Here, we demonstrate that natural organic matter (NOM) in soil impacts PrPTSE detection by immunoblotting. Methods commonly used to extract PrPTSE from soils release substantial amounts of NOM, and NOM inhibited PrPTSE immunoblot signal. The degree of immunoblot interference increased with increasing NOM concentration and decreasing NOM polarity. Humic substances affected immunoblot detection of prion protein from both deer and hamsters. We also establish that after interaction with …

Comparing Crop Land Net Primary Production Estimates From Inventory, A Satellite-Based Model, And A Process-Based Model In The Midwest Of The United States Zhengpeng, Zhengpeng Li, Shuguang Liu, Zhengxi Tan, Normann B. Bliss, Claudia J. Young, Tristram O. West, Stephen M. Ogle

United States Geological Survey: Staff Publications

Accurately quantifying the spatial and temporal variability of net primary production (NPP) for crop-lands is essential to understand regional cropland carbon dynamics. We compared three NPP estimates for croplands in the Midwestern United States: inventory-based estimates using crop yield data from the U.S. Department of Agriculture (USDA) National Agricultural Statistics Service (NASS); estimates from the satellite-based Moderate Resolution Imaging Spectro radiometer (MODIS) NPP product; and esti-mates from the General Ensemble bio geochemical Modeling System (GEMS) process-based model. The three methods estimated mean NPP in the range of 469–687 g C m⁻²yr⁻¹and total NPP in the range …

Summary Of The Snowmastodon Project Special Volume: A High-Elevation, Multi-Proxy Biotic And Environmental Record Of Mis 6–4 From The Ziegler Reservoir Fossil Site, Snowmass Village, Colorado, Usa, Ian M. Miller, Jeffrey S. Pigati, R. Scott Anderson, Kirk R. Johnson, Shannon A. Mahan, Thomas A. Ager, Richard G. Baker, Maarten Blaauw, Jordon Bright, Peter M. Brown, Bruce Bryant, Zachary T. Calamari, Paul E. Carrara, Michael D. Cherney, John R. Demboski, Scott A. Elias, Daniel C. Fisher, Harrison J. Gray, Danielle R. Haskett, Jeffrey S. Honke, Stephen T. Jackson, Gonzalo Jiménez- Moreno, Douglas Kline, Eric M. Leonard, Nathaniel A. Lifton, Carol Lucking, H. Gregory Mcdonald, Dane M. Miller, Daniel R. Muhs, Stephen E. Nash, Cody Newton, James B. Paces, Lesley Petrie, Mitchell A. Plummer, David F. Porinchu, Adam N. Rountrey, Eric Scott, Joseph J.W. Sertich, Saxon E. Sharpe, Gary L. Skipp, Laura E. Strickland, Richard K. Stucky, Robert S. Thompson, Jim Wilson

United States Geological Survey: Staff Publications

In North America, terrestrial records of biodiversity and climate change that span Marine Oxygen Isotope Stage (MIS) 5 are rare. Where found, they provide insight into how the coupling of the ocean–atmosphere system is manifested in biotic and environmental records and how the biosphere responds to climate change. In 2010–2011, construction at Ziegler Reservoir near Snowmass Village, Colorado (USA) revealed a nearly continuous, lacustrine/wetland sedimentary sequence that preserved evidence of past plant communities between ~140 and 55 ka, including all of MIS 5. At an elevation of 2705 m, the Ziegler Reservoir fossil site also contained thousands of well-preserved bones …

Geologic Setting And Stratigraphy Of The Ziegler Reservoir Fossil Site, Snowmass Village, Colorado, Jeffrey S. Pigati, Ian M. Miller, Kirk R. Johnson, Jeffrey S. Honke, Paul E. Carrara, Daniel R. Muhs, Gary Skipp, Bruce Bryant

United States Geological Survey: Staff Publications

The geologic setting of the Ziegler Reservoir fossil site is somewhat unusual—the sediments containing the Pleistocene fossils were deposited in a lake on top of a ridge. The lake basin was formed near Snowmass Village, Colorado (USA) when a glacier flowing down Snowmass Creek Valley became thick enough to overtop a low point in the eastern valley wall and entered the head of Brush Creek Valley. When the glacier retreated at about 155–130 ka, near the end of Marine Oxygen Isotope Stage 6, the Brush Creek Valley lobe left behind a moraine that impounded a small alpine lake. The lake …

Toxicity Of Pb‐Contaminated Soil To Japanese Quail (Coturnix Japonica) And The Use Of The Blood–Dietary Pb Slope In Risk Assessment, W. Nelson Beyer, Yu Chen, Paula Henry, Thomas May, David Mosby, Barnett A. Rattner, Valerie I. Shearn-Bochsler, Daniel Sprague, John Weber

United States Geological Survey: Staff Publications

This study relates tissue concentrations and toxic effects of Pb in Japanese quail (Coturnix japonica) to the dietary exposure of soil‐borne Pb associated with mining and smelting. From 0% to 12% contaminated soil, by weight, was added to 5 experimental diets (0.12 to 382mg Pb/kg, dry wt) and fed to the quail for 6 weeks. Benchmark doses associated with a 50% reduction in delta‐aminolevulinic acid dehydratase activity were 0.62mg Pb/kg in the blood, dry wt, and 27mg Pb/kg in the diet. Benchmark doses associated with a 20% increase in the concentration of erythrocyte protoporphyrin were 2.7mg Pb/kg in …

Testing Metapopulation Concepts: Effects Of Patch Characteristics And Neighborhood Occupancy On The Dynamics Of An Endangered Lagomorph, Mitchell J. Eaton, Phillip T. Hughes, James E. Hines, James D. Nichols

United States Geological Survey: Staff Publications

Metapopulation ecology is a field that is richer in theory than in empirical results. Many existing empirical studies use an incidence function approach based on spatial patterns and key assumptions about extinction and colonization rates. Here we recast these assumptions as hypotheses to be tested using 18 years of historic detection survey data combined with four years of data from a new monitoring program for the Lower Keys marsh rabbit. We developed a new model to estimate probabilities of local extinction and colonization in the presence of nondetection, while accounting for estimated occupancy levels of neighboring patches. We used model …

Probit Models For Capture-Recapture Data Subject To Imperfect Detection, Individual Heterogeneity And Misidentification, Brett T. Mcclinktock, Larissa L. Bailey, Brian P. Dreher, William A. Link

United States Geological Survey: Staff Publications

As noninvasive sampling techniques for animal populations have become more popular, there has been increasing interest in the development of capture-recapture models that can accommodate both imperfect detection and misidentification of individuals (e.g., due to genotyping error). However, current methods do not allow for individual variation in parameters, such as detection or survival probability. Here we develop misidentification models for capture-recapture data that can simultaneously account for temporal variation, behavioral effects and individual heterogeneity in parameters. To facilitate Bayesian inference using our approach, we extend standard probit regression techniques to latent multinomial models where the dimension and zeros of the …

Testing Metapopulation Concepts: Effects Of Patch Characteristics And Neighborhood Occupancy On The Dynamics Of An Endangered Lagomorph, Mitchell J. Eaton, Phillip T. Hughes, James E. Hines, James D. Nichols

United States Geological Survey: Staff Publications

Metapopulation ecology is a field that is richer in theory than in empirical results. Many existing empirical studies use an incidence function approach based on spatial patterns and key assumptions about extinction and colonization rates. Here we recast these assumptions as hypotheses to be tested using 18 years of historic detection survey data combined with four years of data from a new monitoring program for the Lower Keys marsh rabbit. We developed a new model to estimate probabilities of local extinction and colonization in the presence of nondetection, while accounting for estimated occupancy levels of neighboring patches. We used model …

Probit Models For Capture-Recapture Data Subject To Imperfect Detection, Individual Heterogeneity And Misidentification1, Brett T. Mcclintock, Larissa L. Bailey, Brian P. Dreher, William A. Link

United States Geological Survey: Staff Publications

As noninvasive sampling techniques for animal populations have become more popular, there has been increasing interest in the development of capture-recapture models that can accommodate both imperfect detection and misidentification of individuals (e.g., due to genotyping error). However, current methods do not allow for individual variation in parameters, such as detection or survival probability. Here we develop misidentification models for capture-recapture data that can simultaneously account for temporal variation, behavioral effects and individual heterogeneity in parameters. To facilitate Bayesian inference using our approach, we extended standard probit regression techniques to latent multinomial models where the dimension and zeros of the …

Effects Of Salinity And Dissolved Organic Matter On Cu Toxicity To Americamysis Bahia In Estuarine Environments, Rabia Nasir

Theses and Dissertations (Comprehensive)

As salinity increases the geochemical speciation of Cu is altered as a result of organic/inorganic complexation/competition. Such salinity changes may further challenge the osmoregulatory capabilities of euryhaline organisms. This chemical-biological interaction complicates the understanding of the impacts of Cu in estuarine waters. Dissolved organic matter (DOM) has been widely established to be an important modifier of Cu toxicity in freshwaters however its effectiveness in modulating Cu toxicity across the range of salinities that occur in estuarine conditions has not been studied in a systematic manner. Site to site differences in DOM quality with respect to the potential for toxicity mitigation …

Field-Scale Water And Solute Transport, Yang Yang

Theses and Dissertations--Plant and Soil Sciences

Spatial variability of soil properties complicates the understanding of water and solute transport at the field scale. This study evaluated the impact of land use, soil surface roughness, and rainfall characteristics on water transport and Br^- leaching under field conditions by means of a new experimental design employing scale-dependent treatment distribution. On a transect with two land use systems, i.e., cropland and grassland, rainfall intensity and the time delay between Br^- application and subsequent rainfall were arranged in a periodically repetitive pattern at two different scales. Both scales were distinct from the scale of surface roughness as described …

Comparative Phylogeography Of Glassfrogs (Vitreorama) Endemic To The Brazilian Altantic Rainforest, Zoe Spanos

Dissertations and Theses

The Brazilian Atlantic Forest harbors one of the most diverse faunas of the world, including 2-3% of all known vertebrate species. Understanding the role of both climate and landscape in shaping current biodiversity patterns has been the focus of many recent phylogeographic studies. Here I explore multiple factors thought to have impacted the generation of local diversity in the Brazilian Atlantic Forest (AF) using two montane, stream-associated species of glassfrogs – V. eurygnatha and V. uranoscopa. I integrate species distribution modeling, path analysis, and molecular data to test the role of climatic stability, rivers, mountain chains, and geographic distance in …

Investigation Of Strategies To Promote Effective Teacher Professional Development Experiences In Earth Science, Carol A. Engelmann

Dissertations, Master's Theses and Master's Reports - Open

This dissertation serves as a call to geoscientists to share responsibility with K-12 educators for increasing Earth science literacy. When partnerships are created among K-12 educators and geoscientists, the synergy created can promote Earth science literacy in students, teachers, and the broader community. The research described here resulted in development of tools that can support effective professional development for teachers. One tool is used during the planning stages to structure a professional development program, another set of tools supports measurement of the effectiveness of a development program, and the third tool supports sustainability of professional development programs. The Michigan Teacher …

Wetlands And Greenhouse Gas Fluxes: Causes And Effects Of Climate Change – A Meta-Analysis, Robert E. Ventura

Pomona Senior Theses

Climate change is one of the largest problems facing this generation. Anthropogenically caused increases of greenhouse gas emissions is a significant culprit to this problem. Although the obvious problems such as cars, industry, and urbanism garnish a significant amount of the criticism, natural sources such as wetlands are also beginning to contribute to this issue. This is becoming increasingly significant as wetlands shift from being sinks of greenhouse gases to becoming sources as various anthropogenic impacts, including global warming itself, begin to affect the health of the wetlands. The aim of this project is to look at four common types …

Sedimentologic, Stratigraphic, And Diagenetic Analysis Of Microbialite-Bearing Lacustrine Rift Sequence Within The Lower Cretaceous Yucca Formation, Indio Mountains, West Texas, Xiaowei Li

Open Access Theses & Dissertations

This study sedimentologically, stratigraphically, and diagenetically analyzed strata of the upper member of the Lower Cretaceous Yucca Formation in the Indio Mountains, West Texas in order to develop an outcrop-based analog model for similar facies that form major hydrocarbon reservoirs in the Pre-salt rift basins of the South Atlantic margin. The lower Cretaceous strata of the Indio Mountains were deposited in rift basins that formed along the eastern margin of the Chihuahua Trough under similar greenhouse climate conditions as the South Atlantic basins.

Eleven lithofacies are recognized from the upper member of the Yucca Formation to the base of the …

Comparative Recharge Rates Of Isolated And Riverine Wetlands, Chenille Hargrove Williams

Theses and Dissertations

Isolated wetlands have a slightly depressed topography surrounded by an upland area. There is no direct surface water connection, as with riverine wetlands; however, there is a groundwater connection that allows isolated wetlands to have similar hydrologic functions to riverine wetlands. This study sought to compare surficial aquifer groundwater recharge rates of several isolated and riverine wetlands in the Coastal Plain of the Carolinas by evaluating soil characteristics, water table fluctuations, and precipitation from January 2012 - September 2012. Data analysis indicated no significant difference in mean recharge rates between the isolated and riverine wetlands at each study site. Whereas …

Upper Pleistocene And Holocene Palaeoenvironmental Records In Cueva Mayor Karst (Atapuerca, Spain) From Different Proxies: Speleothem Crystal Fabrics, Palynology And Archaeology., Virginia Martínez-Pillado, Arantza Aranburu, Juan Luis Arsuaga, Blanca Ruiz-Zapata, Maria José Gil-García, Heather Stoll, Iñaki Yusta, Eneko Iriarte, José Miguel Carretero, R. Lawrence Edwards, Hai Cheng

International Journal of Speleology

The Cueva Mayor karst system of Atapuerca, in Northern Spain, hosts a highly significant record of human occupation from the Pleistocene. The climatic context of the human activities during the Pleistocene-Holocene for this inland site has not been well constrained, since existing records of the palaeoclimatic evolution of the Northern Iberian Peninsula are from more distal coastal and high-elevation sites. In this study, we interpret the palaeoenvironmental information recorded on the petrography of a stalagmite and the pollen spectra of the Sierra de Atapuerca karst system during the last 20 kyr. The integration of both types of records has allowed …

Surface Complexation Of Monosubstituted Organoarsenicals On Hematite: Atr-Ftir Investigations, Md Abdus Sabur

Theses and Dissertations (Comprehensive)

Little is known about the surface chemistry of organoarsenic compounds with iron-containing materials commonly found in geosorbents and arsenic removal technologies. In this thesis, these organoarsenicals include aliphatic and aromatic arsenicals that historically have been used as herbicides, pesticides and in the poultry feed industry, respectively. Attenuated total internal reflectance Fourier transform infrared spectroscopy has been used to study the surface interactions of organoarsenicals at the molecular level under various environmentally-relevant conditions. Kinetic and thermodynamic parameters extracted from these molecular level experiments provide trends that are not observed in any published bulk experiments. Apparent initial rates of adsorption and desorption …

Common Core 4th Grade Environmental Science Lesson Plans For California Teachers, Gillian Schoenfeld

Natural Resources Management and Environmental Sciences

This project and its analyses were conducted to assist California fourth grade elementary school teachers in adjusting to teaching Common Core standards and science curriculum in their classrooms. The project included the creation of lesson plans, which could be utilized throughout the state of California.

As the Common Core standards, California’s Next Generation Science Standards for K- 12, were just proposed in June of 2013, these lesson plans would help teachers update their lessons and provide them materials and concepts of how to do so. These lessons provide higher-order thinking for students, which is the whole concept of the new …

Global Digital Elevation Model Accuracy Assessment In The Himalaya, Nepal, Luke G. Miles

Masters Theses & Specialist Projects

Digital Elevation Models (DEMs) are digital representations of surface topography or terrain. Collection of DEM data can be done directly through surveying and taking ground control point (GCP) data in the field or indirectly with remote sensing using a variety of techniques. The accuracies of DEM data can be problematic, especially in rugged terrain or when differing data acquisition techniques are combined. For the present study, ground data were taken in various protected areas in the mountainous regions of Nepal. Elevation, slope, and aspect were measured at nearly 2000 locations. These ground data were imported into a Geographic Information System …

Ichnology And Paleoecology Of The Jurassic Aztec Sandstone, Heather Marie Stoller

UNLV Theses, Dissertations, Professional Papers, and Capstones

In this study I describe and interpret tracks and trackways of the Jurassic Aztec Sandstone of southern Nevada and southern California. This study involved mapping of all known tracks and trackways, including foot length, stride length, and trackway width. Photogrammetric data, collected by Bureau of Land Management scientists, were utilized for several trackways in Red Rock Canyon National Conservation Area.

More than three hundred tracks belonging to five ichnotaxa were documented within the Aztec Sandstone, including about 165 tridactylGrallator, 250 tetradactyl (four-toed)Brasilichniumtracks, and 7 arthropod trackways ofOctopodichnusandPaleohelcura. Four of the five ichnotaxa were not previously reported from the Aztec Sandstone. …

Origin Of High Levels Of Ammonium In Groundwater, Ottawa County, Michigan, Derrick Lingle

Masters Theses

Groundwater from wells located in and around Hemlock Crossing Park in Ottawa County, Michigan has elevated levels of ammonium. High ammonium concentrations in potable water wells are a common indicator of anthropogenic impact, such as landfill leachate or agricultural activity. Ammonium can also occur in groundwater through the decay of natural organic material. Along with the retrieval of a complete glacial sediment core via rotasonic drilling, numerous chemical and isotopic parameters were used to determine the source of ammonium in the impacted aquifer.

Buried organic material, deposited during the Athens subepisode interglacial period, is in contact with groundwater containing elevated …