MS, Kent State University, 2019, College of Arts and Sciences / Department of Earth Sciences

Wetlands are complex ecosystems with unique biogeochemical and hydrological characteristics. These aspects can be traced to the following biogeochemically distinct domains: sediments, porewater, and surface water. Sulfur can play a critical role in aquatic ecosystems, with potential to influence the biogeochemical cycles of freshwater nutrients and metals. Inorganic sulfur can occur in the natural environment in multiple oxidation states. In the presence of oxygen, reduced sulfur readily oxidizes to form sulfate. Wetland hydrology controls the redox states of sulfur, as well as governing the fates trace metals, major cations, and anions in the wetland ecosystem. By examining wetland hydrology and characterizing the biogeochemistry of different wetland domains (sediment, porewater, and surface water), the export and forms of inorganic sulfur in the wetland can be characterized. The study site for this project was a constructed wetland at the Cleveland Metroparks' Watershed Stewardship Center in Parma, Ohio. The study site had interior zones of differing depths and a dynamic hydrologic regime, which could cause a variation in nutrient residence times and transformations within the wetland. To understand the wetland's hydrology and its relationship to sulfate biogeochemistry, interior water levels, outflow discharge, precipitation, water chemistry, sediment chemistry, and porewater chemistry were monitored from June 2015 to October 2016. High concentrations of sulfate were found in the interior zones (arithmetic mean: 185.7 mg/L) and outflow (arithmetic mean: 228.4 mg/L), while inflow concentrations were variable (ranges across inflows: 9.417-902.2 mg/L). Sulfate concentrations in surface water were found to be the highest in the interior and outflow following an extensive drydown period in Summer 2016. High concentrations of sulfate could also signal that sulfide was present in the wetland, but sulfide was below detection in porewater. However, wetland sediments c (open full item for complete abstract)

Committee: Anne Jefferson (Advisor); Lauren Kinsman-Costello (Advisor); Elizabeth Herndon (Committee Member) Subjects: Biogeochemistry; Environmental Geology; Environmental Management; Environmental Science; Freshwater Ecology; Geology; Hydrologic Sciences; Hydrology; Natural Resource Management; Water Resource Management

Master of Science, University of Akron, 2012, Geology

Caves have the potential to provide insight to landscape evolution. Defining the genesis of the cave in the context of the broader hydrologic system, and dating cave growth, can accomplish this. The present study employed paleohydrologic and sediment studies to construct a relationship between discontinuous sediments preserved in a cave, and paleomagnetic analysis for dating. Haynes Cave exists in the Big Levels karstified limestone upland, in the Appalachian Plateaus physiographic province in Monroe County, West Virginia. The entrance is at 670 m. Current local base level is Second Creek, which has steeply incised to 530 m. The cave is currently dry, with insignificant present catchment. The cave passage shape indicates initial development was phreatic, followed by further development from vadose recharge. The main branch of the cave has two stacked and intertwining levels. These passages trend north-south and end in a gravel choke to the south. A small, sinuous lower level (the Basement) runs 400 m northeast, and 15 m below, the middle section of the main branch. There are multiple episodes of sedimentation and incision. Bedrock scallops and pebble imbrications indicate that drainage in the main level was northwards (toward the present entrance). Flow originated from allochthonous sources that fed into the southern end of the cave, and discharged from a paleospring into Second Creek through the main branch at the northern end of the cave. The recharge area is uncertain, but might have been an upstream reach of Second Creek, or via large sinkholes that are developed on an unnamed major fracture trace. Drainage in the Basement was northeastward, and was fed by vadose water from the main branch. The minimum age of the sediments in the cave exceeds 990 ka, yielding a maximum incision rate of 0.14 m/ka for Second Creek. This rate is much higher than rates calculated in other parts of the Appalachians. Using those rates and elevation above the present base level suggest (open full item for complete abstract)

Committee: Ira Sasowsky Dr. (Advisor); John Peck Dr. (Committee Member); W. Ashley Griffith Dr. (Committee Member) Subjects: Geology; Geomorphology

Doctor of Philosophy, The Ohio State University, 2024, Environment and Natural Resources

Soil physical properties play a crucial role in agricultural productivity and environmental sustainability. This study investigated the seasonal dynamics of soil physical properties under different tillage and drainage practices in poorly drained soils of Ohio, focusing on their interrelationships with soil structure, crop growth, and climate across various agricultural production stages. Soils were sampled under long-term tillage (no-till, NT vs chisel-till, T) and drainage (drained, D vs non-drained, ND) management. Intact soil cores and undisturbed bulk samples were collected at 3 depths in different seasons. The research examined a. soil hydraulic properties, including saturated hydraulic conductivity (Ksat), unsaturated hydraulic conductivity (Ks) and water diffusivity (Ds) at field capacity, field infiltration, and plant available water capacity (AWC), b. soil structure, including bulk density (BD), pore size distribution (PSD), water stable aggregates (WSA), mean weight diameter (MWD), penetration resistance (PR), and aggregate tensile strength (TS), c. soil physical quality index (SQI) with the selected indicators, and d. crop development and climate factors, including crop height, crop yield, ground coverage, air temperature, daily precipitation, and rainfall intensity. Specifically, this thesis aims to: a. Investigate the dynamics of soil hydraulic properties (Ksat, Ks, Ds, field infiltration, AWC) under different tillage and drainage practices. b. Assess the dynamics of soil structure (WSA, MWD, PSD, PR, TS) under different tillage and drainage practices. c. Determine the yield-oriented SQI across different seasons of crop production. In terms of the first objective, results in Chapter 2 showed that NT generally maintained higher Ksat (0.675-0.898 cm/hr vs 0.307-0.572 cm/hr, p=0.001-0.124) in fallowing seasons, especially in surface soils, due to better soil aggregation and ground coverage. However, during growing seasons, NT (0.326-0.774 cm/hr) (open full item for complete abstract)

Committee: Rattan Lal (Advisor); Brian Slater (Advisor); M. Scott Demyan (Committee Member) Subjects: Agriculture; Environmental Science; Natural Resource Management; Soil Sciences; Sustainability

Doctor of Philosophy, The Ohio State University, 2024, Geography

This dissertation offers a comprehensive assessment of future flood risk in Columbus, Ohio, by quantifying future land use changes and evaluating their combined impact with climate change. Additionally, it investigates the potential of green infrastructure as a strategy to mitigate these risks. Objective 1 examines the impact of static land cover assumptions on flood risk. By incorporating urbanization projections from EPA ICLUS to 2100, the greatest land use change varies significantly depending on the climate model and emission scenario. Each climate model (GISS-E2-R, HadGEM2-ES) and scenario (RCP 4.5, RCP 8.5) projects different land use changes, highlighting the sensitivity of future development and climate. GISS-E2-R presents a wet and warm scenario, while HadGEM2-ES simulates hot and dry conditions. Based on these projections, HadGEM2-ES RCP 8.5 had the most substantial average impact on Columbus communities, with a 19.7% change. GISS RCP 8.5 follows closely at 18.6%. Low-density exurban areas experience a 100% increase in GISS-E2-R. The HadGEM2-ES model projected decreases in high-density exurban and suburban areas and increases in low-density exurban and high-density urban areas. Both models predict decreases in exurban and suburban areas under high-emission scenarios, while high-density urban and commercial areas are projected to expand. Five communities experienced the greatest land use change: Hayden Run, Clintonville, State of Oho, Wolfe Park, and Livington Avenue Area. Objective 2 examines the contribution of climate and land use change on flood risk. In Columbus, Ohio, climate change alone is projected to increase streamflow by up to 22% by the late century based on the Oak Ridge Laboratory's CMIP6 streamflow data. However, when considering both climate and land use change, urbanization exacerbates this impact, increasing streamflow by an additional ~8% compared to climate-induced changes alone. Southern Columbus communities, including West Scioto (open full item for complete abstract)

Committee: Steven Quiring (Advisor); Huyen Le (Committee Member); Desheng Liu (Committee Member); Alvaro Montenegro (Committee Member) Subjects: Climate Change; Environmental Justice; Environmental Science; Geographic Information Science; Geography; Hydrology; Physical Geography; Urban Planning; Water Resource Management

Master of Science, The Ohio State University, 2007, Graduate School

Committee: Not Provided (Other) Subjects:

Master of Science, The Ohio State University, 1971, Graduate School

Committee: Not Provided (Other) Subjects:

Master of Science, The Ohio State University, 1968, Graduate School

Committee: Not Provided (Other) Subjects:

Master of Science, The Ohio State University, 2005, Graduate School

Committee: Not Provided (Other) Subjects:

Master of Science, The Ohio State University, 1984, Graduate School

Committee: Not Provided (Other) Subjects:

Doctor of Philosophy, The Ohio State University, 2024, Food, Agricultural and Biological Engineering

Worldwide urbanization and the concurrent increase in impermeable surfaces, such as parking lots, driveways, sidewalks, and other structures, have led to challenges managing runoff in cities. Improperly managed stormwater poses threats to public health, private property, and the environment. Countries worldwide are adopting the use of nature-based approaches known as green infrastructure (GI) to holistically treat environmental stressors resulting from urban development. GI is designed to mimic the natural, pre-development hydrology of the developed area while concurrently improving runoff quality. There are several GI approaches, including permeable pavements (PP), bioretention cells (BRC), and constructed stormwater wetlands (CSW), which can reduce runoff volume, delay and extend runoff timing, improve discharge water quality, and mitigate peak runoff rates from highly impervious catchments. PPs have been used worldwide for decades, but these systems remain infrequently implemented for stormwater management because of ambiguity related to maintaining their long-term hydraulic functionality due to clogging which reduces the PP surface infiltration rate (SIR) and therefore its performance. Measurements of the SIR can inform the extent of clogging, but at present there is a dearth of guidance on how to incorporate SIR data into dynamic PP maintenance plans. In the first chapter of my dissertation, I conducted a review of existing guidance documents to describe the current state of practice for SIR measurement methodologies, PP maintenance guidance, and the use of SIR outcomes to inform PP maintenance plans. Standard and alternative SIR assessment methodologies were described and compared, and modifications and recommendations were provided to clarify testing methods, streamline testing efficiency, and reduce the burden of SIR monitoring. Suggested modifications included requiring regular SIR testing, shortening the duration of SIR tests, and allowing for usage of mo (open full item for complete abstract)

Committee: Ryan Winston (Advisor); Jay Dorsey (Committee Member); Jon Witter (Committee Member); Jiyoung Lee (Committee Member); Jay Martin (Committee Member) Subjects: Ecology; Environmental Engineering; Environmental Management; Hydrology; Microbiology; Water Resource Management

Doctor of Philosophy, The Ohio State University, 2024, Food, Agricultural and Biological Engineering

As catchments become increasingly impervious, urban stormwater pollutant loads, erosional force, and flooding increases. The practice of stormwater management is critical environmental protection that became regulated by the US federal government in the 1970s. With the need to attenuate peak flow rates and reduce the excess stormwater volumes generated from impervious catchments, stormwater control measures (SCMs) were developed such as stormwater detention basins, retention ponds, drainage ditches, and subsurface stormwater detention. Having a variety of SCMs available provides stakeholders with the ability to target specific aspects of stormwater management, including runoff quantity, runoff quality, or other ecosystem services. Regulations have evolved over time to have a greater emphasis on stormwater quality. As such, SCM design has evolved to address pollutant removal in stormwater. Green infrastructure (GI) practices, also called low impact development (LID) SCMs, have gained popularity for stormwater management since the start of the 21st century and incorporate principles of ecological engineering into stormwater management. Examples of GI include a variety of practices that use infiltration through filter media such as rain gardens, bioretention cells (BRCs), and high rate biofiltration (HRBF), permeable pavements, green roofs, and constructed stormwater wetlands (CSWs). The use of GI has benefits in addition to peak flow, volume, and pollutant reduction such as creating habitat for pollinators, cooling urban spaces, and adding attractive green space. Pollutant removal mechanisms vary between GI practices with some systems providing greater sedimentation and treatment of particulates and some providing greater treatment of dissolved pollutants through microbially-mediated transformation, plant uptake, and/or adsorption. Performance of SCMs varies based on design, site characteristics (e.g. topography, soil texture and infiltration capacity, depth to wa (open full item for complete abstract)

Committee: Ryan Winston (Advisor); Jay Dorsey (Committee Member); James Stagge (Committee Member); Jonathan Witter (Committee Member); Jay Martin (Committee Member) Subjects: Environmental Engineering; Environmental Management; Environmental Science; Hydrology; Water Resource Management

Master of Science (MS), Ohio University, 2024, Environmental Studies (Voinovich)

Growing human population has led to an accelerated rate of degradation of natural resources. One of the most alarming impacts is water quality impairment globally as a result of nutrient pollution from agricultural and other non-point sources. This study assesses the efficiency of wetland restoration project in mitigating nutrient pollution in the Bell Run-South Fork Licking watershed in Ohio. Nutrient pollution, primarily stemming from nitrogen and phosphorus runoff from agricultural activities poses water quality challenges to the region. The restoration of an 80-acre portion wetland aims to ultimately improve the water quality of the Soth Fork Licking River by reducing nutrient loading into Bloody Run and its tributaries. Through pre- and post-construction assessments, the study evaluated changes in nutrient concentrations and hydrological inputs. Results indicate significant reductions in nitrogen species loading postconstruction. However, there was an increase in phosphorus loading following the construction period. Hydrological inputs' to the site influences on nutrient dynamics were evident, with storm events leading to higher nutrient discharge. Continued monitoring during high-flow periods is recommended to improve understanding of nutrient dynamics within the restored site and inform management strategies for optimizing the wetland's nutrient retention capacity over time.

Committee: Natalie Kruse (Committee Chair); Sarah Davis (Committee Member); Daniel Che (Committee Member) Subjects: Environmental Studies

Master of Science, The Ohio State University, 2024, Civil Engineering

Estuarine marshes occur at the interface of terrestrial riverine flows and oceans or lakes. As such, they play a crucial role in the movement, storage, and fluxes to the atmosphere, of carbon. We monitored CH4 fluxes, and the concentration of dissolved organic carbon (DOC) in the Old Woman Creek (OWC) estuary, Ohio. Gas exchange chamber measurements and sampling of surface water for DOC concentration were conducted simultaneously at three locations with distinct hydraulic characteristics: the outflow, mid-flow, and backflow areas, and at three different relative depths (deep, intermediate, and shallow) within each location. Samples were conducted monthly, over the summer and autumn of 2023 (i.e., month 1 to month last). We investigated the temporal and spatial correlation between DOC and CH4 fluxes in OWC, with a focus on the inflow dynamics from nearby rivers and the wetland's hydrological regime. We hypothesized that the high CH4 flux levels observed in OWC are driven by the wetland's intake of DOC, and short-term depth changes (due to barrier opening and closing) and long-term depth changes (due to changes in water levels and inundation) influences methane emissions. We found that DOC in the wetland's inflow positively correlates with the river stage, but contrary to our initial hypothesis, elevated DOC levels within the wetland did not significantly contribute to methane emissions. However, we found that DOC concentrations varied by depth, but not temporally when other factors (temperature, depth, river stage) were considered. Spatially, the outflow area had the highest DOC concentration, with deep depths in each hydrological location exhibiting higher DOC concentrations. CH4 fluxes varied spatially, with the outflow area recording the least methane emissions, while the mid-flow area exhibited higher methane concentrations. Intermediate depths in each hydrological location recorded higher methane emissions. Interestingly, we found that long-term trends of CH4 fl (open full item for complete abstract)

Committee: Gil Bohrer (Advisor); Andy May (Committee Member); James Stagge (Committee Member) Subjects: Atmospheric Sciences; Biogeochemistry; Climate Change; Environmental Engineering; Environmental Science; Freshwater Ecology

Master of Science, The Ohio State University, 2024, Environmental Science

I introduce Bayesian Optimization for Anything (BOA), a high-level BO framework and model wrapping toolkit, which presents a novel approach to simplifying Bayesian Optimization (BO) with the goal of making it more accessible and user-friendly, particularly for those with limited expertise in the field. BOA addresses common barriers in implementing BO, focusing on ease of use, reducing the need for deep domain knowledge, and cutting down on extensive coding requirements. A notable feature of BOA is its language-agnostic architecture. Using JSON serialization, BOA facilitates communication between different programming languages, enabling a wide range of users to integrate BOA with their existing models, regardless of the programming language used, with a simple and easy-to-use interface. This feature enhances the applicability of BOA, allowing for broader application in various fields and to a wider audience. I highlight BOA's application through several real-world examples. BOA has been successfully employed in a high-dimensional (184 parameters) optimization Soil & Water Assessment Tool (SWAT+) model, demonstrating its capability in parallel optimization with SWAT and non-parallel models, such as SWAT+. I employed BOA in a multi-objective optimization of the FETCH3.14 model. These case studies illustrate BOA's effectiveness in addressing complex optimization challenges in diverse scenarios.

Committee: Gil Bohrer (Advisor); James Stagge (Committee Member); Joel Paulson (Committee Member) Subjects: Artificial Intelligence; Computer Science; Environmental Engineering; Environmental Studies; Statistics

PHD, Kent State University, 2023, College of Arts and Sciences / Department of Earth Sciences

Climate change is threatening urban areas, including by exacerbating impacts from stormwater runoff on urban streams. Understanding the uncertainties associated with climate change impacts and the resilience of current adaptation strategies are challenging, but this understanding is the key for effective urban water management. Green infrastructure is commonly used to mitigate the effects of stormwater runoff, and it is considered an important climate adaptation strategy. The hydrologic impacts of green infrastructure are poorly understood at the watershed scale, because most of the decisions relating to stormwater management are not optimized and made on the parcel or neighborhood scale. Therefore, the main aim of this research is to quantify the impacts of climate change under different uncertainties and optimized green infrastructure on the flow regime of urban streams by using numerical modeling approaches, which in turn will be helpful for informing decisions by stormwater managers and policy makers. In this dissertation, I first quantified climate change impacts and compared multiple sources of uncertainty within and between climate and hydrological models for an urban watershed near Cleveland, Ohio. One hundred years continuous streamflow obtained from a distributed hydrological model was divided into historical, initial, mid, and late 21st century shows that there will be an increase in future streamflows with exceedance probabilities of 0.5%-50%. Flood with all return periods will increase through the 21st century for most climate projections and parameter sets. For this watershed, hydrological model parameter uncertainty was large relative to inter-climate model spread, for near term moderate to high flows and for many flood frequencies. Optimizations of bioretention cells, swales, and permeable pavements at 14%, 42% and 70% treatment levels were completed using the simulation-optimization tool OSTRICH-SWMM in two urban watersheds located in Cleveland (open full item for complete abstract)

Committee: Anne Jefferson (Committee Co-Chair); David Singer (Committee Co-Chair); Kuldeep Singh (Committee Member); David Costello (Committee Member); Aditi Bhaskar (Committee Member) Subjects: Civil Engineering; Climate Change; Geology; Hydrologic Sciences; Hydrology; Water Resource Management

Doctor of Philosophy, The Ohio State University, 2023, Environmental Science

Climate change is affecting water resources worldwide. Projected increases in precipitation and temperature could exacerbate existing water quality problems of excess erosion and nutrient runoff from agricultural landscapes and further degrade water quality. The Soil and Water Assessment Tool (SWAT) is a widely used model to quantify sediment and nutrient pollution under various land management and climatic scenarios. In the first two chapters herein, SWAT is employed to quantify the impacts of climate change and agricultural conservation in achieving water quality goals in two key Laurentian Great Lakes watersheds: the Maumee River Watershed and Old Woman Creek. The Maumee River Watershed is the largest contributor of phosphorus to Lake Erie, and reducing phosphorus loss in this watershed is key to managing the extent of the annual Lake Erie harmful algal bloom in the Western Lake Erie Basin. A novel approach of using a multi-institutional watershed model ensemble was employed and forced by temperature and precipitation predictions from an ensemble of Global Climate Models. Findings indicated increased conservation resulted in statistically significant (p ≤ 0.05) reductions in annual loads of total phosphorus (41%), dissolved reactive phosphorus (18%), and total nitrogen (14%) under the highest emission climate scenario (RCP 8.5). Additionally, this study helped to inform uncertainty introduced by the watershed model in climate change analysis. Old Woman Creek is one of the few remaining watersheds with a natural lacustrine wetland of the Laurentian Great Lakes. However, the river feeding into the wetland has impairments for sediment and phosphorus that local conservationists are working to address. This study aimed to aid near- and long- term conservation planning by quantifying conservation effects in a recent climate and under climate change. Climate change results indicated a possible 11% increase in sediment near the watershed outlet. In the recent and (open full item for complete abstract)

Committee: Margaret Kalcic (Advisor); Gil Bohrer (Advisor); James Hood (Committee Member); Jay Martin (Committee Member) Subjects: Environmental Science

Master of Science, University of Toledo, 2023, Geology

Infiltration capacity varies spatially as a result of heterogeneous soil characteristics such as texture, structure, and residual moisture content that affect the rate of infiltration. Assessing the spatial distribution of infiltration capacity (Ksat), and the behavior of infiltrating water in the subsurface, is necessary to understand the soil water dynamics in wetlands. In this study, the spatial distribution of Ksat was assessed by combining apparent electrical conductivity (ECa) from electromagnetic imaging (EMI) with field measurements of double ring infiltration tests (DRIT). The ECa data was collected using a Geonics EM38-MK2 equipped with a single transmitter and two receiver coils spaced at 0.5 and 1 m from the transmitter. The EMI results showed a distribution of ECa ranging from 10 mS/m to 40 mS/m for the 0.5 m transmitter-receiver spacing and 8 mS/m to 36 mS/m for the 1 m transmitter-receiver spacing. Results of the DRIT produced a distribution of Ksat ranging from 0.01 mm/min to 0.91 mm/min. A least-squared linear regression model was employed to establish a correlation between estimated Ksat and ECa, yielding R2 values of 0.62 and 0.8 for the 0.5 m and 1 m transmitter-receiver spacing, respectively, indicating the effectiveness of EMI in predicting Ksat. Based on the regression model, a leave-one-out technique was used to predict Ksat based on ECa, which showed a fair to good predictive capability. The behavior of infiltrating water, particularly in terms of vertical and lateral flow, as well as the subsurface recharge and discharge mechanisms, which depend on the subsurface hydrostratigraphy, was assessed with a combination of ERI models and lithologic logs. It was observed that a silty clay loam topsoil layer of approximately 0.7 m overlays a clayey loam layer of about 0.5 m, which, in turn, is underlain by a diamicton unit of approximately 1.2 m. Beyond 1.2 m depth, based on the well logs and the regional stratigraphy, the resistivity plot is (open full item for complete abstract)

Committee: Kennedy Doro (Committee Chair); James Martin-Hayden (Committee Member); Timothy G. Fisher (Committee Member) Subjects: Geology; Geophysics; Hydrology

Doctor of Philosophy, The Ohio State University, 2023, Electrical and Computer Engineering

Observing dynamic changes in the Earth's surface water is crucial for understanding and modeling the global hydrological cycle. Rapid changes in surface water, such as flooding and wetland inundation, are some of the most important events, yet quantitative observations of these events are among the most challenging to acquire. Current satellite-based flood and wetland inundation products are largely based on optical remote sensing methods, which exhibit limited ability to detect surface water through rain, clouds, and vegetation. While current satellite microwave remote sensing using radar can overcome some of these limitations, these instruments are on single satellite platforms and may overpass regions on multi-week timescales, missing flash flooding and dynamic inundation events. Recently, a novel remote sensing technique known as Global Navigation Satellite System Reflectometry (GNSS-R) has shown great potential in the detection of terrestrial surface water beneath clouds and vegetation. NASA's Cyclone Global Navigation Satellite System (CYGNSS) mission is a small satellite constellation using GNSS-R instruments that receive reflections of L-band GPS signals known to penetrate rain, clouds, and vegetation, and has a regional sub-daily revisit rate. CYGNSS has recently shown the potential to resolve small-scale and dynamic hydrological features over land, such as rivers, lakes, wetlands, and urban flooding. CYGNSS is an eight-satellite constellation, resulting in sub-daily measurement frequencies that provide a unique opportunity to observe short timescale changes. However, CYGNSS measurements occur in sparse, quasi-random tracks since GPS reflections can occur anywhere in the field of view. This makes understanding the observability of dynamic events more difficult as compared to simpler imaging instruments. Changes in signal-to-noise ratio (SNR) that indicate a dynamic change in the scene are confounded by inherent variability due to other sources, incl (open full item for complete abstract)

Committee: Joel Johnson (Advisor); Lee Potter (Committee Member); Robert Burkholder (Committee Member); Andrew O'Brien (Committee Co-Chair) Subjects: Remote Sensing

Master of Science (MS), Ohio University, 2023, Environmental Studies (Voinovich)

Intensive farming practices have led to the release of sediments and nutrients, primarily nitrogen and phosphorus, into the environment, which account for nearly half of all water pollution issues in the United States. Among the affected areas is the Bloody Run Swamp in Ohio, an historical swamp drained for agricultural purposes. A restoration project being undertaken by the Stream and Wetlands Foundation aims to retain water, sediments and nutrient on the 80-acre site by restoring the former wetland and constructing a natural channel design channel to replace the ditch to the north of the site. In this study, the pre-construction and during-construction hydrology and sediment concentration at seven sites were assessed to see the impact of the stream restoration and wetland construction aimed at reducing nutrient and sediment pollution. Water samples were gathered and assessed for total dissolved solids (TDS), total solids (TS), and total suspended solids (TSS). While the construction period was wetter than the pre-construction period, there were periods of sediment transport. Most sediments were transported at TDS rather than TSS, with TSS concentrations increasing with large runoff events. The results suggest that the restoration project aimed at reducing nutrient and sediment pollution in the Bloody Run Swamp has the potential to be effective.

Committee: Natalie Kruse Daniels (Advisor); Kelly Johnson (Committee Member); Sarah Davis (Committee Member) Subjects: Environmental Engineering; Environmental Science; Environmental Studies; Hydrology; Sedimentary Geology

Master of Science, University of Akron, 2022, Geology

In northern Ohio a complex aquifer system includes a surficial glacial drift aquifer and a carbonate bedrock aquifer. The bedrock aquifer carries regional flow and discharges through karst springs near and in Sandusky Bay. This investigation employed quarterly comprehensive geochemical analyses along with high-resolution temperature/ conductivity monitoring in the discharge zone at Castalia Blue Hole, Miller's Blue Hole, and a flowing artesian well to give a better understanding of the groundwater system. Nutrient input to Lake Erie from the karst springs was also determined. In addition, the paleohydrology of the system under changing ice conditions and lake levels was explored. Temperature and electrical conductance were monitored at 15-minute intervals. Water samples determined major ion chemistry, agrichemicals, and nutrients. A paleocross-section was constructed based on ice sheet thickness to determine paleo recharge history to evaluate past groundwater flow. The regional water flows from potentiometric high areas in Logan and Morrow Counties towards Sandusky Bay. Groundwater recharge would formerly have taken place under the ice sheet, driving flow southward, which is opposite of modern-day flow. Low seasonal variation in chemistry suggests that the groundwater comes from a regional source and that the aquifer behaves as a diffuse medium. Further evidence is relatively invariant water temperature over the sampling period. Measured temperatures at the 3 sites differ, partially due to challenges with appropriate deployment. Specific conductance is high and relatively stable, but varies between sites with Miller's Blue Hole having the highest variability and Stidham Well the least. Miller's Blue Hole and Stidham Well are close in values for specific conductance but range differently for temperature from 7.65-12.56°C and 12.00- 12.12°C respectively. Small dips in specific conductance correlate with precipitation and sugge (open full item for complete abstract)

Committee: Ira Sasowsky (Advisor); David Steer (Committee Member); John Senko (Committee Member); George Bullerjahn (Committee Member) Subjects: Environmental Geology; Geology; Hydrology