Physical Sciences and Mathematics Commons^™

Memory Response: Exposure History Dependence Of Microbial Mediated Transformations Of Substrates In Groundwater, Charles Joseph Paradis

Doctoral Dissertations

The flow, transport, and reactivity of dissolved-phase constituents in an unconfined and shallow aquifer were characterized, in situ, by utilizing the single-well push-pull test method. In the first study, the re-oxidation/mobility of uranium, in the presence of nitrate oxidant, was shown to be mitigated by preferential oxidation/mobilization of solid-phase, reduced, sulfur-bearing species. These results indicated that establishing conditions conducive to uranium reduction and the formation of reduced sulfur-bearing species can increase the efficacy of sustained uranium reduction/immobility in the presence of re-mobilizing oxidants. In the second study, the analytical solution to describe the one-dimensional displacement of the center of …

Application Of Hydrogeophysical Imaging In The Reynolds Creek Critical Zone Observatory, Travis Nielson

Boise State University Theses and Dissertations

The critical zone is defined as the upper most portion of the crust extending from the top of unweathered bedrock to the top of the vegetation canopy. It is the zone in which inorganic rock is transformed into biologically useful soils and saprolites in a process termed weathering. Because the critical zone is the connection between the subsurface and surface it plays a role in a wide variety of biological, hydrologic, and climatic processes. Understanding the critical zone though is inherently difficult because its scale and heterogeneity often means direct sampling methods, e.g. soil pits and cores, under represent the …

Twentieth Century Channel Change Of The Green River In Canyonlands National Park, Utah, Alexander E. Walker

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Since the early 20^th century, river channels of the Colorado River basin have narrowed, decreasing available riparian and aquatic habitat. Changes are considered to be the result of three major factors: wide-spread water development, increasing hydroclimate variability and the invasion of non-native tamarisk (Tamarix spp.), altering flow regime and sediment supply. Different studies have reached different conclusions about the relative roles of flow regime, sediment supply and tamarisk in causing narrowing.

I investigated channel change in the lower Green River within Canyonlands National Park to describe channel changes in the 20^th century and understand the roles …

A Geophysical Investigation Of Stratigraphy And Structure On St. Catherines Island, Georgia, Anne M. Delua

Honors College Theses

Geophysical tools were used to investigate potential structural and stratigraphic pathways of the salt water intrusion that is affecting the surficial aquifer on St. Catherines Island, Georgia. Ground penetrating radar (GPR) is a geophysical tool that uses electromagnetic waves to view the subsurface. GPR is used for a variety of applications stratigraphically, biologically, and anthropogenically. GPR electromagnetic waves react to changes in density and composition and type and percentage of pore fluids in sediment and rock. GPR waves also react to interfaces including fractures and faults. GPR waves exhibit attenuation and decreased return signal in materials such as clay. Fresh …

Precipitation And Sea Level Rise Impacts On Groundwater Levels In Virginia Beach, Virginia, Brett A. Buzzanga

OES Theses and Dissertations

Global sea level rise (SLR) is one of the most immediate impacts of climate change, and poses a significant threat to low-lying coastal communities worldwide. The metropolitan region of Hampton Roads in Southeastern Virginia is one such community, and one where knowledge surrounding SLR is rapidly accumulating. However, most of the research is focused exclusively on surface water processes despite the presence of a shallow groundwater table closely connected to them. SLR will continue to cause the groundwater table to increase in tidally influenced areas of Hampton Roads, and thereby decrease storage capacity of the unsaturated zone.

This study investigates …

To What Extent Might Beaver Dam Building Buffer Water Storage Losses Associated With A Declining Snowpack?, Konrad Hafen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Dams built by North American Beaver create natural water storage and slow water as it moves through streams. In portions of streams with beaver dams, these effects have been observed to decrease the peak magnitude of floods and increase base flow during annual summer droughts. In the western United States changes to streamflow patterns have been observed in recent decades with large spring floods coming earlier in the year, causing annual summer droughts to start earlier and last longer. These changes are linked to decreasing snowpack which acts as the most significant natural water storage reservoir by holding onto precipitation …

An Analysis Of The Relationship Between Snowpack And Groundwater Across Utah Watersheds., Samuel Wright

Electronic Theses and Dissertations

This thesis examined what type of relationship existed between snow water equivalence (SWE) volume and groundwater elevation within six sub-watersheds in Utah. Data was gathered on SWE from seventeen SNOTEL sites and groundwater elevation data was gathered from six continuously monitored groundwater wells. This data was gathered for January through May for 2011, 2013, and 2014 in order to represent the water conditions that were above average, below average, and average respectively. Using MLR formulas the total SWE for each sub-watershed was determined for each year/month. Afterwards a correlation analysis was performed to determine if any association existed between SWE …

Nutrient Loading Reduction In A Tile Drained Agricultural Watershed Through Watershed-Scale Cover Cropping: A High Resolution Analysis, Benjamin Gerald Bruening

Theses and Dissertations

Nutrient pollution originating from agricultural regions in the Midwest is a serious issue, leading to pollution of drinking water sources as well as large hypoxic zones in the Gulf of Mexico. The source of much of this contamination has been shown to be runoff from agricultural fields in the Upper Mississippi River Basin. One method that has been shown to reduce this pollution from the Upper Mississippi River Basin is the planting of winter cover crops. Winter cover crops such as rye and tillage radish have been shown to significantly reduce nitrate exported from agricultural fields, even in tile-drained watersheds …

Modeling Channel Response To Dam Removal In Lansing, Michigan, Using Swat, Ryan Filbin

Masters Theses

The removal of dams has increased in recent decades in the United States, largely resulting from decaying infrastructure and greater efforts to restore rivers to a more natural, free-flowing state. Dam removal presents the opportunity for increased public safety, improved environmental prosperity, and improved economic prosperity in conjunction with riverfront revitalization projects. The City of Lansing, Michigan, contains two moderate-to high-risk dams along the Grand River that pose a significant risk to the surrounding area in the event of structural failure.

The Soil and Water Assessment Tool (SWAT) is applied to model the impacts of the Moores Park Dam and …

Groundwater And Tidal Controls On Wetland Hydrology, Julie J. Metz Wetland Mitigation Bank, Woodbridge, Virginia, Benjamin Stuart Hiza

OES Theses and Dissertations

Julie J. Metz Wetlands Mitigation Bank, a 92-hectare freshwater wetland located in Woodbridge, Virginia, borders the tidally-influenced Neabsco Creek. Seven pods separated by earthen berms were built by Wetland Studies and Solutions Inc. (WSSI) in 1995 and 1997 by removing the toe of small sandy alluvial fans and covering the underlying coarse gravel bed with a low permeability cap. The basal Quaternary gravels were deposited in a creek valley incised into a thick sand-and-clay Cretaceous delta. The alluvial-fan apron developed at the base of steep slopes along the sides of the valley. Pressure transducer data from five monitoring wells along …

Characterizing Coastal Marsh Groundwater Hydrology With Multichannel Electrical Resistivity Tomography, Matthew R. Kestner

Electronic Theses and Dissertations

Subsurface waters are highly enriched in nutrients compared to surface waters in the coastal salt marsh environment and may, therefore, have a large effect on biogeochemical processes. There have been numerous studies examining marsh platform hydrology, however, there is a lack of information on the hyporheic zone within tidal creeks in coastal salt marsh environments. Hyporheic exchange has been studied in various non-tidal freshwater systems and verified as a significant pathway for solute transport in typical stream settings. The total volume of water cycled through salt marsh tidal creek hyporheic zones could prove to be a significant component of the …

Response Of Soil Properties To 23-25 Years Of Diverse Crop Rotations And Tillage Systems In South Dakota, Usa, Abdullah H. Alhameid

Electronic Theses and Dissertations

Diverse cropping systems and no-till (NT) are beneficial in improving soil organic carbon (SOC) and other soils properties. The present study was conducted to evaluate the interactions and impacts of long-term tillage and diverse crop rotation systems on soil quality indicators that include a range of soil chemical, physical, hydrological, and microbial properties. The study was established in 1991 at Beresford, South Dakota and included three crop rotation systems [2-yr; maize (Zea mays L.)-soybean (Glycine max L.), 3-yr; maize-soybean-oat (Avena sativa L.), and 4-yr; maize-soybean-oat-wheat (Triticum aestivum L.)] managed under two tillage systems (NT and CT; conventional- tillage). Soil sampling …

Rock Glacier Hydrology In The San Juan Mountains, Colorado, Emilio Ian Mateo

Electronic Theses and Dissertations

Rock glaciers are unique geomorphological features located in alpine environments and are found in the San Juan Mountains of Colorado. There has been little research done on rock glaciers compared to their ice glacier counterparts. Most rock glaciers are located on the northern slope aspect in mountainous areas (Janke 2007), however, there are multiple in southwest Colorado with different aspects. This research project asks how slope aspect influences the hydrological processes of streams sourced from rock glaciers in the San Juan Mountains. This project focused on three basins that are adjacent to each other and share a common peak, Gilpin …

Developing A Hydrological Monitoring Program For Ponds In Wapusk National Park, Manitoba, Using Water Isotope Tracers, Stephanie Roy

Theses and Dissertations (Comprehensive)

Northern lake-rich landscapes are vulnerable to increases in surface air temperatures and are changing in dynamic ways. Current meteorological records indicate that some of the greatest warming in the past century has occurred in the Hudson Bay Lowlands (HBL). As the HBL is an extensive wetland consisting of hundreds of thousands of shallow lakes and ponds, it is difficult to anticipate the long-term implications that climate change will have on pond water balance. To develop and implement long-term monitoring of hydrological conditions, sampling of pond water isotope composition has occurred during the past six years in Wapusk National Park (WNP), …

Detecting Regional Groundwater Discharge To The Clark Fork River, Melinda Horne

Undergraduate Theses, Professional Papers, and Capstone Artifacts

In this study, Radon-222 (²²²Rn) measured in stream water and groundwater was used to constrain the quantity of groundwater discharge along a 22 km reach of the Clark Fork River as it runs through Missoula, MT. Dissolved ²²²Rn samples were taken at 2 km intervals along a reach extending from the confluence of the Clark Fork and the Blackfoot River near Bonner, MT to the confluence with the Bitterroot River on the northwestern edge of the Missoula Valley. Groundwater samples were taken from wells in an alluvial aquifer near Rattlesnake Creek, and combined with previous data from …