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Assessing The Effects Of Riverbank Inducement On A Shallow Aquifer In Southeastern Wisconsin, Laura Rachel Fields-Sommers Dec 2015

Assessing The Effects Of Riverbank Inducement On A Shallow Aquifer In Southeastern Wisconsin, Laura Rachel Fields-Sommers

Theses and Dissertations

The state of Wisconsin is heavily reliant upon groundwater resources. In order to induce river water, implementation of shallow wells with close proximity to river systems is being used as a method to augment groundwater supplies in portions of southeastern Wisconsin. However, river bank wells (RBI) are vulnerable to contamination due to their close interaction with the surface water. The vulnerability increases when induced surface waters contain municipally treated waste water. The objective of this study was to determine the current and potential influences of riverbank inducement, recharge mechanisms of the well field, and to discriminate the sources of sodium …


The Mixing Of A River Into Coastal Waters At Two Beaches: Environmental Factors, E. Coli Contributions And Applications For Predictive Models, Adrian Jordan Koski Dec 2015

The Mixing Of A River Into Coastal Waters At Two Beaches: Environmental Factors, E. Coli Contributions And Applications For Predictive Models, Adrian Jordan Koski

Theses and Dissertations

Beach closures and public health protection are confounded by analytical procedures that result in delays in notification of adverse water quality conditions and the lack of affordable analytical methods to identify pollutant sources. Attempts have been made to develop predictive frameworks using ancillary hydrometeorological data to statistically anticipate deteriorated water quality. Many urban coastal beaches are impacted by river runoff. In Kenosha Wisconsin, beach sanitary survey data from two beaches adjacent to the mouth of the Pike River were examined to ascertain whether simple river-lake mixing models identified river influence on coastal water quality and improved predictions of beach advisories. …


Monitoring And Modeling The Hydrological Performance Of Extensive Green Roof Systems, Joseph Seidl Dec 2015

Monitoring And Modeling The Hydrological Performance Of Extensive Green Roof Systems, Joseph Seidl

Theses and Dissertations

Urban stormwater runoff causes many problems for watersheds located within large metropolitan areas, including such detrimental effects as flooding, erosion, pollution, and the increased risk of combined sewerage overflows. Increased amounts of impervious areas resulting from urban sprawl have also been shown to escalate stormwater flows, which exacerbates water management issues in these metropolitan areas. Water resource engineers have progressively turned toward green infrastructure to solve stormwater problems, and green roof systems represent one type of this green infrastructure. As of current, however, green roof systems are largely underused in as an effective stormwater management tool.

The major factor limiting …


Addressing Potential Risks And Challenges Of Co2 Geologic Sequestration, Ethan Guyant Dec 2015

Addressing Potential Risks And Challenges Of Co2 Geologic Sequestration, Ethan Guyant

Theses and Dissertations

Carbon Capture and Geologic Storage is a viable technology to reduce the concentration of CO2 emitted to the atmosphere, however there remains challenges and risks associated with implementing this technology. One of the challenges, and the focus of Chapter 2, is maintaining the injectivity of the reservoir throughout the entire injection period of a project. While potential risks include the pressurization of the reservoir and the leakage of CO2 and/or brine out of the storage reservoir which is the focus of Chapter 3. A consequence of injecting dry-supercritical CO2 is that it results in salt precipitation in the near well …


Field And Laboratory Study Of The Flàajökull Glacier, Iceland, William Russell Jacobson, Jr. Dec 2015

Field And Laboratory Study Of The Flàajökull Glacier, Iceland, William Russell Jacobson, Jr.

Theses and Dissertations

The increased surface melting of the outlet glaciers of the Vatnajökull Ice Cap has a profound affect on the dynamics of the ice-bed couple and landform genesis. Soft-bedded glaciers are largely inaccessible, which creates a problem. One challenge is to understand the complex interactions of the glacier bed and its resultant depositional and deformational landform systems. This study investigates an outlet glacier from the Vatnajökull Ice Cap, described herein as the Fláajökull glacier system. To circumvent some of these problems, three separate projects were conducted in this dissertation: (1) magnetic fabric study of effective pressure (difference between the ice-overburden pressure …


The Great Lakes' Regional Climate Regimes, Noriyuki Sugiyama Dec 2015

The Great Lakes' Regional Climate Regimes, Noriyuki Sugiyama

Theses and Dissertations

For the last couple of decades, the Great Lakes have undergone rapid surface warming. In particular, the magnitude of the summer surface-warming trends of the Great Lakes have been much greater than those of surrounding land (Austin and Colman, 2007). Among the Great Lakes, the deepest Lake Superior exhibited the strongest warming trend in its annual, as well as summer surface water temperature. We find that many aspects of this behavior can be explained in terms of the tendency of deep lakes to exhibit multiple regimes characterized, under the same seasonally varying forcing, by the warmer and colder seasonal cycles …


Superimposed And Auxiliary Dunes Of The Northern Namib Sand Sea: A Ground-Penetrating Radar Study, Clayton K. Chandler Dec 2015

Superimposed And Auxiliary Dunes Of The Northern Namib Sand Sea: A Ground-Penetrating Radar Study, Clayton K. Chandler

Theses and Dissertations

Understanding modern features allows for their use as analogues for understanding the environments of the past and even environments on other planetary bodies. This study uses Ground-Penetrating Radar (GPR) to image the near surface sedimentary structures on a large linear dune in the northern Namib Sand Sea and image the sedimentary structure of an auxiliary dune. GPR data was collected using a 200 MHz antenna with a continuous scan method and was processed by removing direct arrival, gain balancing, migration and more which produced the highest resolution imagery from this region to date. Large dune data was analyzed to determine …


Cooling Before Super-Eruption: No Role For Rejuvenation In The Cottonwood Wash Tuff Magma Body, Southern Great Basin Ignimbrite Province, Utah And Nevada, Keryn Tobler Ross Dec 2015

Cooling Before Super-Eruption: No Role For Rejuvenation In The Cottonwood Wash Tuff Magma Body, Southern Great Basin Ignimbrite Province, Utah And Nevada, Keryn Tobler Ross

Theses and Dissertations

The model of rejuvenation of a near-solidus crystal mush to produce large volumes of crystal-rich magma is tested here by analyzing the mineralogical, chemical, modal, and physical characteristics of the 31.1 Ma super-eruptive (2000 km3) Cottonwood Wash Tuff. It is the oldest in a series of three so-called “monotonous intermediate” ignimbrites from the Indian Peak-Caliente volcanic field in southern Utah and Nevada. A crystal-rich (~50% Pl > Qz ≈ Hbl ≈ Bt > Mag ≈ Ilm > Cpx + Zrn + Ap+ Po) dacite (62 – 69 wt% SiO2), the Cottonwood Wash Tuff is similar in age, volume, mineralogy, crystallinity, and elemental composition …


Cooling Before Super-Eruption: No Role For Rejuvenation In The Cottonwood Wash Tuff Magma Body, Southern Great Basin Ignimbrite Province, Utah And Nevada, Keryn Tobler Ross Dec 2015

Cooling Before Super-Eruption: No Role For Rejuvenation In The Cottonwood Wash Tuff Magma Body, Southern Great Basin Ignimbrite Province, Utah And Nevada, Keryn Tobler Ross

Theses and Dissertations

The model of rejuvenation of a near-solidus crystal mush to produce large volumes of crystal-rich magma is tested here by analyzing the mineralogical, chemical, modal, and physical characteristics of the 31.1 Ma super-eruptive (2000 km3) Cottonwood Wash Tuff. It is the oldest in a series of three so-called "monotonous intermediate" ignimbrites from the Indian Peak-Caliente volcanic field in southern Utah and Nevada. A crystal-rich (~50% Pl > Qz ≈ Hbl ≈ Bt > Mag ≈ Ilm > Cpx + Zrn + Ap+ Po) dacite (62 - 69 wt% SiO2), the Cottonwood Wash Tuff is similar in age, volume, mineralogy, crystallinity, and elemental composition …


Decomposition And Nitrogen Dynamics Of Turtle Grass (Thalassia Testudinum) In A Subtropical Estuarine System, Monica Delgado Dec 2015

Decomposition And Nitrogen Dynamics Of Turtle Grass (Thalassia Testudinum) In A Subtropical Estuarine System, Monica Delgado

Theses and Dissertations

Seagrass beds are pivotal in the functioning of coastal ecosystems in terms of productivity, organic matter turnover and nutrient cycling. Aiming to document decay and nitrogen (N) dynamics of turtle grass (Thalassia testudinum) in a subtropical estuarine system, decomposition patterns of leaves and rhizomes were characterized and compared. Nitrogen usage during decomposition of tissues, and of live tissues and epiphytes growing on live leaves, was also quantified and compared. Stable isotope ratios allowed tracing N within the seagrass bed, following N incorporation into seagrass tissues from the surrounding media (water, sediment). Leaves had a higher N content and decomposed at …


Low-Shield Volcanism: A Comparison Of Volcanoes On Syria Planum, Mars And Snake River Plain, Idaho, Amanda Olivia Henderson Nov 2015

Low-Shield Volcanism: A Comparison Of Volcanoes On Syria Planum, Mars And Snake River Plain, Idaho, Amanda Olivia Henderson

Theses and Dissertations

Volcanoes are key indicators of a planet's internal structure, mechanics, and evolutionary history. Consequently, understanding the types and ages of volcanoes on a planet's surface is an important endeavor. In an attempt to better understand the relationship between morphometry and volcanic processes, we compared low-shield volcanoes on Syria Planum, Mars, with basaltic shields of the eastern Snake River Plain. We used 133 volcanoes on Syria Planum that are covered by Mars Orbiting Laser Altimeter (MOLA) and High Resolution Stereo Camera (HRSC) elevation data and 246 eSRP shields covered by the National Elevation Dataset (NED) for this comparison. Shields on Syria …


Development And Validation Of A Physically Based Ela Model And Its Application To The Younger Dryas Event In The Graubünden Alps, Switzerland, Durban Gregg Keeler Nov 2015

Development And Validation Of A Physically Based Ela Model And Its Application To The Younger Dryas Event In The Graubünden Alps, Switzerland, Durban Gregg Keeler

Theses and Dissertations

The rapid rate of global warming currently underway highlights the need for a deeper understanding of abrupt climate change. The Younger Dryas is a Late-Glacial climate event of widespread and unusually rapid change whose study can help us address this need for increased understanding. Reconstructions from the glacial record offer important contributions to our understanding of the Younger Dryas due to (among other things) the direct physical response of glaciers to even minor perturbations in climate. Because the glacier equilibrium line altitude (ELA) provides a more explicit comparison of climate than properties such as glacier length or area, ELA methods …


Mechanisms And Timing Of Pluton Emplacement In Taranaki Basin, New Zealand Using Three-Dimensional Seismic Analysis, Phillip C. Cammans Oct 2015

Mechanisms And Timing Of Pluton Emplacement In Taranaki Basin, New Zealand Using Three-Dimensional Seismic Analysis, Phillip C. Cammans

Theses and Dissertations

Several off-shore volcano-plutonic complexes are imaged in detail in the Parihaka 3D seismic survey in the Taranaki Basin of New Zealand. Three intrusions were analyzed for this study. Part of the Mohakatino Volcanic Centre (15 to 1.6 Ma), these intrusions have steep sides, no resolvable base reflectors, no internal stratification or structure, and they exhibit doming and faulting in the sedimentary strata above the intrusions. Deformation along the sides is dominated by highly attenuated, dipping strata with dips of 45° or higher that decrease rapidly away from the intrusions. Doming extends several hundred meters from the margins and produced many …


Sedimentology And Stratigraphy Of High-Latitude, Glacigenic Deposits From The Late Paleozoic Ice Age In The Tepuel-Genoa Basin, Patagonia, Argentina, Sarah Rose Survis Aug 2015

Sedimentology And Stratigraphy Of High-Latitude, Glacigenic Deposits From The Late Paleozoic Ice Age In The Tepuel-Genoa Basin, Patagonia, Argentina, Sarah Rose Survis

Theses and Dissertations

The Late Paleozoic Ice Age (LPIA) was the longest lived ice age of the Phanerozoic lasting ~87 million years. During this time multiple, small ice sheets advanced and retreated with alternating glacial and nonglacial intervals across Gondwana. Controversy still remains over the size, timing, and number of ice sheets because the traditional view of Gondwana during this time is of a single, large ice sheet that waxed and waned across the supercontinent. Furthermore, high-latitude glacially-influenced basins during the Carboniferous have received limited attention, underscoring the poor understanding of glacial to non-glacial transitions. The Tepuel Basin in Patagonia, Argentina, was located …


Climate Impact On Groundwater Flow Processes In The Cedar Creek Watershed And Cedarburg Bog, Jackson Graham Aug 2015

Climate Impact On Groundwater Flow Processes In The Cedar Creek Watershed And Cedarburg Bog, Jackson Graham

Theses and Dissertations

A local-scale groundwater-flow model of the Cedar Creek Watershed and Cedarburg Bog area was constructed to determine the effects of future changes in temperature and precipitation on water resources. The Cedar Creek Watershed is a 330 km2 sub-basin of the Milwaukee River Watershed located about 30 km north of Milwaukee. The importance of this watershed lies in its location at the sub-continental divide separating the Mississippi River Basin from the Great Lakes Basin. The coupled steady-state and transient flow models incorporate interaction between surface water features and groundwater-surface water interactions. The 4 layer model simulates the influence of recharge on …


Functional Diversity Of Regional Marine Paleocommunities After The Permo-Triassic Mass Extinction: Case Studies From Panthalassa And Paleo-Tethys, Ashley Ann Dineen Aug 2015

Functional Diversity Of Regional Marine Paleocommunities After The Permo-Triassic Mass Extinction: Case Studies From Panthalassa And Paleo-Tethys, Ashley Ann Dineen

Theses and Dissertations

The Permo-Triassic mass extinction (PTME) was the largest biodiversity collapse in Earth’s history. Published data has been interpreted as indicating that marine ecological devastation following the PTME was protracted and may have lasted 5 million years into the Middle Triassic (Anisian). However, a review of previous literature shows that understanding of biotic recovery is usually based on only a few components of the ecosystem, such as on taxonomic diversity, a single genus/phylum, or shallow water facies. Typically, paleocommunities are considered fully recovered when dominance and diversity are regained and normal ecosystem functioning has resumed. However, to more fully characterize Triassic …


Geologic Mapping Of Ice Cave Peak Quadrangle, Uintah And Duchesne Counties, Utah With Implications From Mapping Laramide Faults, Gabriel J. Poduska Jul 2015

Geologic Mapping Of Ice Cave Peak Quadrangle, Uintah And Duchesne Counties, Utah With Implications From Mapping Laramide Faults, Gabriel J. Poduska

Theses and Dissertations

Geologic mapping (1:24,000 scale) of the Ice Cave Peak quadrangle, Uintah and Duchesne Counties, Utah has produced a better understanding of the geologic structures present in the quadrangle and has increased our understanding of faulting in northeastern Utah. Map units in the quadrangle range in age from late Neoproterozoic to Quaternary and include good exposures of Paleozoic rocks (Mississippian to Permian), limited exposures of Mesozoic rocks, and good exposures of Tertiary strata (Duchesne River Formation and Bishop Conglomerate) deposited during uplift of the Uinta Mountains. Lower Mississippian strata along the south flank of the Uinta Mountains have typically been mapped …


Using Declassified Satellite Imagery To Quantify Geomorphic Change: A New Approach And Application To Himalayan Glaciers, Joshua Michael Maurer Jun 2015

Using Declassified Satellite Imagery To Quantify Geomorphic Change: A New Approach And Application To Himalayan Glaciers, Joshua Michael Maurer

Theses and Dissertations

Himalayan glaciers are key components of earth's cryosphere, acting as hydrological reservoirs vital to many human and natural systems. Most Himalayan glaciers are shrinking in response to changing climate, which will potentially impact water resources, natural hazards, sea level rise, and many other aspects. However, there is much uncertainty regarding the state of these glaciers, as direct field data are difficult to obtain. Accordingly, long-timespan remote sensing techniques are needed to measure changing glaciers, which have memory and often respond to climate on decadal timescales. This study uses declassified historical imagery from the Hexagon spy satellite database to fulfill this …


Detrital Zircon Analysis Of The Taza-Guercif Basin And The Adjacent Rif And Middle Atlas Mountains Of Morocco And X-Ray Fluorescence Chemofacies Analysis Of The Maness Shale Of East Texas, Jonathan Richard Pratt May 2015

Detrital Zircon Analysis Of The Taza-Guercif Basin And The Adjacent Rif And Middle Atlas Mountains Of Morocco And X-Ray Fluorescence Chemofacies Analysis Of The Maness Shale Of East Texas, Jonathan Richard Pratt

Theses and Dissertations

The research in this compilation encompasses three studies leveraging quantitative chemical analyses to interpret the sedimentary record to reconstruct geologic history. The first study surveys the detrital zircon U-Pb and zircon fission-track geochronology of the sedimentary Cretaceous Ketama and Tisiren units of the Rif Mountains, and the Bou Rached sandstones of the Middle Atlas Mountains. All analyzed samples contain a population of Mesoproterozoic crystallization ages formerly unknown to northwest Africa. Possible sources for these ages include the Avalonian terranes now present on the northeastern seaboard of North America, and/or zircons derived from the Amazonian craton and preserved in the Pan-African …


Modeling Lake Michigan Nearshore Carbon And Phosphorus Dynamics, Joseph Henry Fillingham May 2015

Modeling Lake Michigan Nearshore Carbon And Phosphorus Dynamics, Joseph Henry Fillingham

Theses and Dissertations

Dreissenid mussels, in particular quagga mussels (Dreissena rostiformis bugensis), are transforming the Lake Michigan ecosystem by clearing the water column, recycling phosphorus and modifying benthic habitat. These impacts are thought to have caused observed declines in the spring phytoplankton bloom in Lake Michigan, as well as changes to food web structure and declines in the abundance of critical invertebrate and fish species. In the nearshore zone, the resurgence of benthic Cladophora algae to nuisance levels not observed since phosphorus loading abatement policies instituted in the 1970s has also been attributed to water column clearing and phosphorus recycling by mussels. Using …


Paleoecology Of Glacial And Non Glacial Carboniferous Faunas During The Late Paleozoic Ice Age In Patagonia, Nicole Braun May 2015

Paleoecology Of Glacial And Non Glacial Carboniferous Faunas During The Late Paleozoic Ice Age In Patagonia, Nicole Braun

Theses and Dissertations

The Late Paleozoic Ice Age (LPIA) records the only icehouse to greenhouse transition in Earth’s history that involved complex marine and terrestrial life and serves as an analogue for Quaternary climate change. Identifying biotic responses to paleoenvironmental variations during the LPIA is important in order to understand how our modern fauna may respond to contemporary climate change. Low-paleolatitude (far-field) marine faunas far from ice centers have been recognized and used as a global proxy for biotic responses to the LPIA, but the biotic responses in high-paleolatitude (near-field) regions close to Gondwanan ice centers have received much less attention. We tested …


Hydrothermal Acid-Sulfate Alteration At Krafla And Námafjall, Ne Iceland: Implications For Gusev Crater And Meridiani Planum, Mars, George L. Carson May 2015

Hydrothermal Acid-Sulfate Alteration At Krafla And Námafjall, Ne Iceland: Implications For Gusev Crater And Meridiani Planum, Mars, George L. Carson

Theses and Dissertations

Opaline silica, sulfate, and phyllosilicate-bearing deposits have been detected on Mars from both obiters and rovers, indicating extensive aqueous alteration of the basaltic surface, some of which likely occurred under hydrothermal conditions. Ongoing hydrothermal acid-sulfate alteration of Mars-like high-Fe (15.48-16.27 wt. % Fe2O3T) basalts and hyaloclastites in northeastern Iceland was studied to help interpret the products of alteration in analogous environments on ancient Mars. The Krafla and Námafjall areas feature intense surface alteration in gas- (fumarole) and fluid- (hot spring/mud pot) dominated settings. Influx of H2S gas (H2S + 2O2 = H2SO4) produced steam-derived acid-sulfate waters with pH values 1.96-2.50 …


Paleoredox Geochemistry And Bioturbation Levels Of The Exceptionally Preserved Early Cambrian Indian Springs Biota, Poleta Formation, Nevada, Usa, Jonah Meron Novek May 2015

Paleoredox Geochemistry And Bioturbation Levels Of The Exceptionally Preserved Early Cambrian Indian Springs Biota, Poleta Formation, Nevada, Usa, Jonah Meron Novek

Theses and Dissertations

The early Cambrian Indian Springs biota, western Nevada, USA exhibits Burgess Shale-type (BST) preservation of a diverse array of animal phyla, including the earliest definitive echinoderms. It therefore provides an important window on animal life during the Cambrian radiation. The objective of this study is to analyze the trace metal paleoredox geochemistry and bioturbation levels of this BST deposit in order to characterize the paleoenvironmental conditions in which these animals lived and their fossils were preserved. A total of 28 rock samples were collected from outcrops at three previously reported intervals of exceptional preservation at the Indian Springs locality, as …


Microbially Induced Sedimentary Structures As An Ecological Niche In Subtidal Early Triassic Environments Of Eastern Panthalassa, Erin Wimer May 2015

Microbially Induced Sedimentary Structures As An Ecological Niche In Subtidal Early Triassic Environments Of Eastern Panthalassa, Erin Wimer

Theses and Dissertations

Early Triassic microbially induced sedimentary structures (MISS) are a critical link in understanding the dynamics between changing environmental conditions and their effect on marine communities. The Permo-Triassic mass extinction (PTME) resulted in vacated ecospace and reduced bioturbation that allowed MISS to expand into Early Triassic subtidal environments. Data from southern Idaho and Montana indicate that MISS inhabited and proliferated in subtidal marine environments during the Griesbachian. This propagation led to changes in shallow substrate geochemical conditions that directly affected macrofaunal communities. The proliferation of microbial mats would have created anoxic and euxinic porewaters and made vertical bioturbation physiologically difficult. Geochemical …


Utilizing Remote Sensing Imagery To Monitor Vegetation Change Within World Heritage Sites, Mimi Eve Hatzis Apr 2015

Utilizing Remote Sensing Imagery To Monitor Vegetation Change Within World Heritage Sites, Mimi Eve Hatzis

Theses and Dissertations

ABSTRACT

World Heritage sites provide a glimpse into the stories and civilizations of the past. There are currently 1007 unique World Heritage properties with 779 being classified as cultural sites, 197 as natural sites, and 31 falling into the categories of both cultural and natural sites (UNESCO & World Heritage Centre, 1992-2015). However, of these 1007 World Heritage sites, at least 46 are categorized as in danger and this number continues to grow. These unique and irreplaceable sites are exceptional because of their universality. Consequently, since World Heritage sites belong to all the people of the world and provide inspiration …


Revisiting Tired Old Fields With New Technologies: Three Dimensional Modeling And Structural Analysis Of The Dudley Pool Oil Reservoir, Edgar County, Il, Jordan M. Martin Apr 2015

Revisiting Tired Old Fields With New Technologies: Three Dimensional Modeling And Structural Analysis Of The Dudley Pool Oil Reservoir, Edgar County, Il, Jordan M. Martin

Theses and Dissertations

The purpose of this thesis is to better understand the Dudley Pool oil reservoir, a small, mature oil field, using geologic and geophysical data. The research focused on three-dimensional subsurface modeling of stratigraphy, structure, and porosity, to establish a more thorough understanding of oil occurrence at the Dudley Pool. An emphasis was placed on calculations of potential recoverable oil in order to determine implications on future production possibilities. This thesis also discusses the efficacy of three-dimensional modeling as an effective tool for evaluating, and potentially modifying, production efforts in mature petroleum fields with limited and/or poor-quality data. The modeling and …


Model Of Residence Time And Analysis Of Nitrogen Removal For Two Constructed Wetlands At The Franklin Demonstration Farm In Lexington, Illinois, Emma Singh Baghel Apr 2015

Model Of Residence Time And Analysis Of Nitrogen Removal For Two Constructed Wetlands At The Franklin Demonstration Farm In Lexington, Illinois, Emma Singh Baghel

Theses and Dissertations

Pollution from nonpoint agricultural runoff has become a major problem facing our streams and rivers today. Not only are fish and aquatic life affected, but so is the quality of our drinking and recreational water resources. Studies have shown that wetlands have proven to be the most cost-effective and low maintenance method of removing nonpoint or diffused contaminate inputs. The biological processes and removal of nutrients in wetlands depend on the total surface area available for microbial activity in the soil and a certain period of water retention time. Since chemical processes take time, the measure of residence time is …


Effects Of Physical Characteristics Of Urban Storm Sewersheds On Water Quality In Bloomington, Il, Alicia Terese O'Hare Apr 2015

Effects Of Physical Characteristics Of Urban Storm Sewersheds On Water Quality In Bloomington, Il, Alicia Terese O'Hare

Theses and Dissertations

Increasing urbanization has consequences for surface water quality. Stormwater is a large component of urban water degradation that is poorly understood. Precipitation is quickly transported via underground pipes, from the land to the stream without following water's natural flow path. Studies have correlated detention ponds with improved water quality and impervious surface cover with degraded water quality. However, other physical characteristics within a storm sewer shed including the presence of sump pumps, area and pipe miles may also affect the stormwater quality. We chose 18 storm sewer systems in Bloomington, IL. We measured pH, temperature, conductivity, dissolved oxygen, chloride, nitrate, …


Stoichiometric Controls On Denitrification In High Nitrate Watersheds, Brian Grebliunas Feb 2015

Stoichiometric Controls On Denitrification In High Nitrate Watersheds, Brian Grebliunas

Theses and Dissertations

Watershed biogeochemistry throughout Midwestern agroecosystems have been altered through hydrologic manipulation and over-application of nitrogenous fertilizers. As a result, nitrate (NO3-N) export from subsurface drainage has negative impacts on local and downstream ecosystem health. Wetland installation has proven to be a viable option for targeted management where a large proportion of NO3-N is removed through the bacterially mediated process denitrification. For denitrification to maintain high rates under prolonged NO3-N saturation, a stable supply of labile dissolved organic carbon (DOC) is required. The focus of this dissertation was to study how the stoichiometry of agricultural wetlands limits denitrification within a controlled …


Validity Of Holocene Analogs For Ancient Carbonate Stratigraphic Successions: Insights From A Heterogeneous Pleistocene Carbonate Platform Deposit, Colby Hazard Feb 2015

Validity Of Holocene Analogs For Ancient Carbonate Stratigraphic Successions: Insights From A Heterogeneous Pleistocene Carbonate Platform Deposit, Colby Hazard

Theses and Dissertations

Observations of modern carbonate depositional environments and their accompanying depositional models have been used for decades in the reconstruction and interpretation of ancient carbonate depositional environments and stratigraphic successions. While these Holocene models are necessary for interpreting their more ancient counterparts, they inherently exclude important factors related to the erosion, diagenesis, and ultimate preservation of sediments and sedimentary structures that are ubiquitous in shallow marine carbonate environments. Andros Island, Bahamas is an ideal location to examine the validity of Holocene conceptual models, where geologically young (Late Pleistocene) limestones can be studied immediately adjacent to their well-documented modern equivalents. For this …