Earth Sciences Commons^™

Groundwater Flow And Water Clarity At Cenotes In The Yucatan Peninsula, Laura Rossana Fracica Gonzalez

Graduate Research Theses & Dissertations

Characterizing and predicting groundwater flow in complex karst aquifers poses significant challenges. This study explores the potential application of Acoustic Doppler Current Profiler (ADCP) technology for in-situ groundwater flow measurement within sinkholes (cenotes) in the Yucatan Peninsula, Mexico. Two specific questions are addressed: 1) Can ADCP determine flow within Yucatan Peninsula sinkholes? 2) Are groundwater flow vectors related to water clarity in open cenotes? The geological setting of the Yucatan Platform is characterized by horizontal sedimentary strata with highly permeable limestones and extensive karst features. The research focuses on the Holbox fracture zone, where groundwater flow dynamics remain elusive. The …

Improving Accessibility And Understanding: Studying The Impact Of Human Activities And Dam Removals On Anadromous Fish Species In The Pacific Northwest, Adia F. Bennett

Scripps Senior Theses

Human activities in North American watersheds have significantly impacted anadromous fish, causing some species of salmon and steelhead to become threatened and endangered. These fish hold ecological, cultural, and economic importance, yet factors such as habitat destruction, overfishing, pollution, climate change, and hydroelectric dams continue to degrade populations. Dams are particularly harmful to anadromous fish, sparking a recent movement advocating for dam removals. This study uses NOAA’s 2022 Biological Viability Assessment to examine the response of anadromous fish to recent dam removals in the Pacific Northwest. Four populations were selected to analyze due to their interaction with sites that had …

Migrating Whooping Crane Activity Near U.S. Air Force Bases And Airfields In Oklahoma, David A. Brandt, Aaron T. Pearse, Mark T. Bidwell, John Conkin, Matthew Butler

United States Geological Survey: Publications

The Aransas-Wood Buffalo population of Grus americana (Linnaeus, 1758; whooping cranes) migrates through the United States Great Plains, encountering places substantially altered by human activity. Using telemetry data from 2017 to 2022, we investigated whooping crane migration behavior around U.S. Air Force bases in Oklahoma. Our study focused on potential collision risks between whooping cranes and aircraft, a substantial concern for aviation safety. We determined that activity was greatest at Kegelman Air Force Auxiliary Airfield, near whooping crane critical habitat. On average, 61 percent of marked whooping cranes used locations west of Kegelman Air Force Auxiliary Airfield and Vance Air …

Determining The 2022-2023 Mass Balance Of The Palisade Glacier In The Sierra Nevada Mountains Of California With Remote Sensing, Density Modeling, And Temperature-Index Techniques, Vijay Jain, Eric Grosfils, Sarah Kavassalis

CMC Senior Theses

Small, alpine glaciers, such as those in the Sierra Nevada, are difficult to study because of their small size and remoteness, however, they are important recorders of the impacts of climate change in temperate, alpine environments. Previous studies have attempted to characterize the health of these glaciers using extent change techniques, but these methodologies can only roughly approximate the rudimentary measurement of changing ice volume. This thesis uses the Airborne Snow Observatory Inc.’s (ASO’s) aerial lidar snow depth datasets to perform a mass balance calculation for the Palisade Glacier over the remarkable 2022-2023 water year (October 1 through September 30), …

Hardness Removal By A Continuous Flow Electrochemical Reactor From Different Types Of Water, Shahad Fadhil Alrubaye, Naseer A. Al Haboubi, Hussein A. Al-Amili, Aiman H. Al-Allaq, Dhuha Ahmed Mohammed

Mechanical & Aerospace Engineering Faculty Publications

The present study focuses on the technique of hardness removal by using a novel reactor performing an electrocoagulation (EC) process. The variation of alkalinity is also recorded. Continuous flow experiments were conducted for Total Hardness (TH) removal using a transparent plastic reactor using aluminum plate electrodes that have holes so that the water flows through the plates in a zigzag way. The influence of various operating parameters such as the number of plates (two and four), flow rate (600, 1000 L/h), and water type (Tigris River & rejected water from Reverse Osmosis system RO) was investigated. The results showed that …

Factors Affecting Electrocoagulation Process For Different Water Types: A Review, Shahad Fadhil Abed Al-Rubaye, Naseer A. Alhaboubi, Aiman H. Al-Allaq

Mechanical & Aerospace Engineering Faculty Publications

Raw water must meet specific physical, chemical, and biological requirements to be suitable for drinking. There are various techniques available for treating wastewater, and aside from conventional methods that involve chemicals, electrocoagulation is an efficient and advanced approach. Electrocoagulation has proven effective in treating many pollutants, including bacteria, viruses, iron, fluoride, sulfate, boron, hardness, and turbidity. Total suspended solids, organic and inorganic materials, chemical oxygen demand COD, biochemical oxygen demand BOD, and color. It finds extensive application in treating different types of water and wastewater due to its exceptional ability to remove diverse contaminants. Recently, electrocoagulation has garnered significant attention …

Using Phenology To Unravel Differential Soil Water Use And Productivity In A Semiarid Savanna, Blake Steiner, Russell L. Scott, Jia Hu, Natasha Mcbean, Andrew Richardson, David J. P. Moore

University Administration Publications

Savannas are water-limited ecosystems characterized by two dominant plant types: trees and an understory primarily made up grass. Different phenology and root structures of these plant types complicate how savanna primary productivity responds to changes in water availability. We tested the hypothesis that productivity in savannas is controlled by the temporal and vertical distribution of soil water content (SWC) and differences in growing season length of understory and tree plant functional types. To quantify the relationship between tree, understory, and savanna-wide phenology and productivity, we used PhenoCam and satellite observations surrounding an eddy covariance tower at a semiarid savanna site …

Water Quality Contaminants Long-Term Spatial Analysis Along The Upper Clark Fork River Superfund Site Between Warm Springs And Garrison, Montana, Raegan Michele Osentowski

Undergraduate Theses, Professional Papers, and Capstone Artifacts

Long-term data of heavy metal contaminants, cadmium, copper, lead, arsenic, and zinc were compiled from the Montana Department of Environmental Quality, DEQ, and the United States Geological Survey, USGS, to investigate the effects of remediation on water quality along the upper Clark Fork River superfund site. Long-term data sets were analyzed at CFR-03A, CFR-27H, CFR-34, and SS-25 along the upper Clark Fork River and Silver Bow Creek. CFR-03A and CFR-27H had full remediation in the immediate vicinity, SS-25 had on-going remediation in the immediate vicinity, and CFR-34 had no remediation in the immediate vicinity. Analysis of heavy metal contaminants is …

Groundwater Vulnerability Assessment And Dye Trace Of War Fork River In Daniel Boone National Forest, Will Hemenover

Mahurin Honors College Capstone Experience/Thesis Projects

Daniel Boone National Forest plays a key role in preserving much of Kentucky’s karst regions, natural resources including timber, mineral deposits, and biodiversity, including over 300 species of concern. The health of these environments is determined by surface and groundwater streams in the forest, and karst systems are an integral environment where these systems are active. War Fork, a tributary to the Kentucky River in Jackson County, Kentucky, is a remote and understudied hydrologic system in the Daniel Boone National Forest that contains recreational and logging land uses. Due to karst areas being susceptible to contamination because of rapid water …

Assessing Microplastic Contamination Within Karst Groundwater Basins In Kentucky, Maaz Fareedi

Theses and Dissertations--Earth and Environmental Sciences

The input and abrasion of plastic waste in the environment has long been known to form microplastics (MPs). These ubiquitous contaminants are easily mobilized into hydrologic systems. MPs are now being found in karst aquifers around the world, including several across Kentucky, USA. Due to their size (< 5 mm in diameter), chemical properties, abundance, and wide distribution, MPs pose numerous ecological hazards, including uptake by organisms and as substrates for contaminant sorption. Karst groundwater is especially vulnerable to surface contaminants; however, knowledge of the extent of karst MP contamination is limited, with most studies focused on individual sites or small areas. In this study, we created a MP contamination dataset for 30 karst springs and 10 locations where cave sediments were characterized across Kentucky. MP concentrations in groundwater samples ranged from 0 to 41.1 items/L and yielded an average of 4.9 ± 8.7 items/L. Sediment MP concentrations ranged from 0 to 306 items/kg. We performed statistical analyses and linear regressions to examine whether groundwater MP concentrations could be explained by factors including land use, population density, basin area, numbers of sinkholes, and sinking streams. Our models revealed that population density, agrarian land use, sinking stream density, and basin area were related to MP concentrations. All factors except basin area trended positively with MP concentration, while basin area trended negatively. These relations are generally corroborated by existing literature, however they indicate that further studies with considerably larger sample sizes are needed to determine mechanistic relationships.

Leveraging Uncertainty To Understand The Causes And Consequences Of Observed Climate Change, Alexander Reid Gottlieb

Dartmouth College Ph.D Dissertations

Detecting and attributing climate change to date is essential to understanding the harm global warming has caused and the threat it poses in the future. Yet detecting and attributing historical climate change and its attendant impacts is challenging owing to observational uncertainties in the historical record, the difficulty of isolating the forced response from unforced variability, and the methodological ambiguity on how to best map climate variability and change onto climate impacts. In this thesis, I use the study system of Northern Hemisphere snow to demonstrate how synthesizing a wide array of observational and climate model data with methods from …

River Response To Removal Of A Small Dam And Replacement With A Roughened Channel, Chandler Sabin

All Master's Theses

Relatively few studies have analyzed how the removal of small dams and re-engineering of the channel affect river channel processes. The low-head Nelson Dam was built in 1920 on the Naches River in central Washington, causing two miles of aggraded sediments. This resulted in upstream flooding and excessive downstream incision that led to ineffective irrigation diversions, and hindered fish spawning. Nelson Dam was removed in 2021 and replaced with a graded, roughened, nature-like channel and a newly engineered diversion that was completed in 2023. The research presented here quantifies the effects of the Nelson Dam removal and channel redesign on …

A Comparison Of Sediment Accumulation Effectiveness Behind Beaver Dam Analogues, One Rock Dams, And Post-Assisted Log Structures On East Foster Creek, Douglas County, Wa, Griffin Hansen

All Master's Theses

Waterways are valuable resources for communities and habitats, but are subject to degradation in the form of incision. This is a type of streambed erosion where streams narrow and deepen. Sediment control dams were placed on East Foster Creek in Douglas County, WA to control incision following the 2020 Pearl Hill fire. This study examined sediment capture in the ponds behind these dams, which included beaver dam analogues (BDAs), one rock dams (ORDs), and post-assisted log structures (PALS). Sediment capture may be influenced by several factors, including dam type, height, width, distance between dams, vegetation, land use, topography, soil type, …

The Effect Of Seasonal Ice Cover Duration On Shoreline Erosion In Lake Michigan, Ryan S. Navarre

Dissertations, Master's Theses and Master's Reports

Shoreline erosion in Lake Michigan has been a significant concern for coastal management. Promoting coastal stability and resilience is paramount to protecting these environments, especially amid climate change. While several factors are key in understanding shoreline erosion, seasonal ice cover duration is a prominent yet understudied factor in the Great Lakes region. Here, the relationship between ice cover duration and shoreline erosion rates is assessed across 7 regions of Lake Michigan. An ice cover duration dataset was created for Lake Michigan for 2011 – 2020 and its shorelines were digitized for years with available high-resolution aerial imagery. The statistical relationship …

(Non-) Recovery Of An Agricultural Stream From Straightening And Dredging, Aras Anderson Mann

Graduate Theses, Dissertations, and Problem Reports (ETD)

In recent history, natural, meandering streams have been straightened and dredged to reduce flooding. While this practice can be effective in reducing flooding locally, it often results in the degradation of stream water quality and aquatic ecosystems. A straighter channel inherently increases the stream gradient, which could increase flow velocity, shear stress, and potentially downstream sediment yield. Studies have shown that straightened, channelized streams often begin to return to a meandering pattern 35-50 years post-channelization. Yet cross-sectional surveys and air photo analysis of the stream reach in this study, Deckers Creek, indicate little to no observable trend of the stream …

Investigating Drought Response And Paleoclimate Potential Of A New Network Of White Oak Chronologies In Western Kentucky, Usa, Audrey J. Heichelbech, Maegen L. Rochner, Megan Gibson

Undergraduate Research Events

In Kentucky, historic and paleo-climate data are limited, and current understanding of long-term climate change in the state relies on instrumental data spanning only 1895-present. Proxy data are necessary to extend the temporal and spatial span of climate information. One potential proxy source for Kentucky is tree ring data, but currently, only four such datasets are publicly available on the International Tree Ring Data Bank (ITRDB). Archaeological and archival timber sources may help to fill in this gap. In the 1940s, Florence Hawley-Ellis, the first woman dendrochronologist, collected samples of white oak (Quercus alba L.) from four counties in western …

Locating And Assessing Oregon Trail Ruts With Aerial Stereophotographs, Satellite Imagery And Lidar, P.R. Hanson, Robert Matthew Joeckel, L. M. Howard

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

Exploring The Consistency Of Flow Regimes Within And Among Ecoregions Of The Southeastern United States, Frank Paul Braun Iv

College of Graduate Studies: Theses & Dissertations

Human manipulation of river systems has long been a known contributor to the loss of freshwater biodiversity. By accounting for environmental causes of hydrologic variation among rivers, we can better understand how ecoregion mediates flow regimes and forecast species that may be at risk. Presumably, natural variation associated with ecoregion boundaries exerts strong influence on flow regimes, and may mediate relationships between other features (e.g., land use, dam operations) and hydrology. However, such between-ecoregion variation is poorly investigated, particularly at fine spatial and temporal scales. I characterized 10 hydrologic metrics, representing the five key dimensions of the flow regime (magnitude, …

Geoelectrical And Hydrochemical Characterization Of Submarine Groundwater Discharge In Florida Bay, Ifeanyi Emmanuel Eze

College of Graduate Studies: Theses & Dissertations

Florida Bay, situated at the southern tip of Everglades National Park and underlain by the Miami Limestone formation, is an ecosystem of global significance. Over the past century, the bay has faced threats such as droughts, seagrass mortality, and hypersalinity. Despite various studies and management efforts, the dynamics of submarine groundwater discharge (SGD) in the region remain underexplored. Given that SGD plays a significant role in the chemical dynamics of coastal ecosystems, it warrants thorough investigation. This study aims to characterize the spatial and temporal patterns of SGD in Florida Bay by surveying three basins – Rankin, Whipray, and Rabbit …

Temporal Microplastic Concentration Fluctuations Within An Agricultural Creek And Groundwater In Relation To Farming Practices, Jennifer Abel

Graduate Research Theses & Dissertations

Microplastics (MPs) in agriculture have been well-documented. Agrochemicals, organic fertilizers, and farming equipment all contribute plastic to agricultural soils, groundwater, and surface water and are utilized in different capacities throughout the year. It is unknown how the specific utilization of these products affects the concentration of MPs being input into the environment. Previous research has been primarily related to detection and transport of MPs in soils, groundwater, and surface water. I am unaware of any studies that have taken into consideration farming practices and seasons, and how they may affect any fluctuations in MP concentrations. Water samples (20 L) were …

Characterizing Mountainous Bedrock Groundwater Systems Across Gradients In Topography And Lithology In Western Montana, David L. Baude

Graduate Student Theses, Dissertations, & Professional Papers

Mountain aquifer groundwater systems remain one of the least understood hydrologic systems in upland hydrology. In this study, we aim to characterize bedrock groundwater system dynamics and bedrock-saprolite interactions across a variety of landscape positions and lithology. We investigate groundwater hydraulics, recharge temperature and elevation, residence times, and bedrock recharge rates across two mountainous headwater catchments in west central Montana. We used a suite of environmental tracers (³H, CFCs, SF₆, and ⁴He) and residence time distribution models to estimate groundwater mean residence times over a range of timescales from decades to millennia. Tracers were sampled …

Delayed Coastal Inundations Caused By Ocean Dynamics Post-Hurricane Matthew, Kyungmin Park, Emanuele Di Lorenzo, Yinglong J. Zhang, Tal Ezer, Fei Yi

CCPO Publications

Post Hurricane Abnormal Water Level (PHAWL) poses a persistent inundation threat to coastal communities, yet unresolved knowledge gaps exist regarding its spatiotemporal impacts and causal mechanisms. Using a high-resolution coastal model with a set of observations, we find that the PHAWLs are up to 50 cm higher than the normal water levels for several weeks and cause delayed inundations around residential areas of the U.S. Southeast Coast (USSC). Numerical experiments reveal that while atmospheric forcing modulates the coastal PHAWLs, ocean dynamics primarily driven by the Gulf Stream control the mean component and duration of the shelf-scale PHAWLs. Because of the …

Submarine Groundwater Discharge At A Mega-Tidal Beach, Raymond D. Craddock, Aaron A. Mohammed, Joseph J. Tamborski, Barret L. Kurylyk

OES Faculty Publications

Tidally influenced groundwater systems in coastal environments represent important mixing zones of fresh groundwater and circulating seawater, manifesting as submarine groundwater discharge (SGD). Water circulation induced by tidal pumping enhances the exchange of chemicals between aquifers and coastal waters and thereby influences the biogeochemistry of coastal zones. Here, we report the results of an SGD field study conducted at a steep, mega-tidal sand and gravel beach along the Canadian coast of the Bay of Fundy, a region with the world's highest tides (semi-diurnal tidal ranges exceeding 10 m). Several physical and geochemical measurement techniques were employed to document the spatiotemporal …

Marine Emissions Of Methanethiol Increase Aerosol Cooling In The Southern Ocean, Charel Wohl, Julián Villamayor, Martí Galí, Anoop S. Mahajan, Rafael P. Fernández, Carlos A. Cuevas, Adriana Bossolasco, Qinyi Li, Anthony J. Kettle, Tara Williams, Roland Sarda-Esteve, Valérie Gros, Rafel Simó, Alfonso Saiz-Lopez

OES Faculty Publications

Ocean-emitted dimethyl sulfide (DMS) is a major source of climate-cooling aerosols. However, most of the marine biogenic sulfur cycling is not routed to DMS but to methanethiol (MeSH), another volatile whose reactivity has hitherto hampered measurements. Therefore, the global emissions and climate impact of MeSH remain unexplored. We compiled a database of seawater MeSH concentrations, identified their statistical predictors, and produced monthly fields of global marine MeSH emissions adding to DMS emissions. Implemented into a global chemistry-climate model, MeSH emissions increase the sulfate aerosol burden by 30 to 70% over the Southern Ocean and enhance the aerosol cooling effect while …

Enhancing A Computer Model To Evaluate Rainwater Harvesting And Reuse Strategies For Landscape Irrigation Under Current And Future Climate Conditions, Siyu Li

Electronic Theses & Dissertations (2024 - present)

Urbanization and climate change have detrimental impacts on water quantity and quality. Rainwater harvesting/reuse for landscape irrigation with rain barrels/cisterns, which can assist urban hydrological/water quality restoration and provide a beneficial resource for irrigating landscape, holds significant potentials in urban areas under current and future climates. However, the impacts of rainwater harvesting/reuse strategies for landscape irrigation under a changing climate need to be comprehensively evaluated to assist decision-making. In addition, a comprehensive tool is needed to help stakeholders develop efficient strategies to harvest rainwater for landscape irrigation with rain barrels/cisterns.

To address the needs, the simulation of the sub-daily hydrological …

Joint Interpretation Of Ert And Self-Potential Data To Characterize The Subsurface Geology And Hydrodynamics Along The Sutherland Supply Canal And Paxton Siphon Inlet, Paxton, Nebraska., M. K. Aboushanab, D. R. Hallum, R. M. Joeckel

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

Nebraska Statewide Groundwater-Level Monitoring Report 2023, Aaron R. Young, Mark E. Burbach, Sue Olafsen Lackey, Robert Matthew Joeckel, Nawaraj Shrestha, Jeffrey Westrop

Conservation and Survey Division: Faculty and Staff Publications

This report is a synthesis of groundwater-level monitoring programs in Nebraska. It is a continuation of the series of annual reports and maps produced by the Conservation and Survey Division (CSD) of the University of Nebraska in cooperation with the U.S. Geological Survey (USGS) since the 1950s. Groundwater-level monitoring began in Nebraska in 1930 to survey the state’s groundwater resources and observe changes in its availability on a regular basis. The CSD and USGS cooperatively developed, maintained, and operated an observation-well network throughout the state. These two agencies were responsible for collecting and archiving this information, and for making it …

Leveraging High Resolution Classifications And Random Forests For Hindcasting Decades Of Mesic Ecosystem Dynamics In The Landsat Time Series, N. E. Kolarik, Nawaraj Shrestha, T. Caughlin, J. S. Brandt

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

Transient Electromagnetic (Tem) Survey For Targeted Drilling On The Kurtzhals Property, Cedar County, Nebraska, Jesse Korus, Katherine (Katie) Cameron, Michele Waszgis

Conservation and Survey Division: Faculty and Staff Publications

The Kurtzhals property is in Section 19, Township 30N, Range 3 in Cedar County, Nebraska. The present land use is agricultural row crop, but past use included hog production. Two active irrigation wells are located on adjacent properties to the west and southwest. An irrigation well was installed in the northwest corner of the property in 2022. Due to the low yield (300 gallons per minute) of this well, Mr. Kurtzhals seeks to install an additional irrigation well to supplement the first. Several unsuccessful test holes had been drilled prior to the present survey. The purpose of this survey was …

Multiscale Characterization Of Splays Produced By A Historic, Rain-On-Snow Flood On A Large Braided Stream (Platte River, Central Usa), J. T. Korus, R. M. Joeckel, A. R. Mittelstet, N. Shrestha

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.