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Tebbe, Hope MEvaluation of Indoor Air Quality in Four Nursing Home Facilities in Northwest Ohio
Master of Science in Occupational Health, University of Toledo, 2017, Occupational Health (Industrial Hygiene)
Indoor air quality (IAQ) is considered one of the top five environmental risks to the public’s health. Older adults are more vulnerable to health complications associated with indoor air contaminants because of their decreased immune system and age-associated health problems, as well as the fact that they spend up to 95 percent of their time indoors. Area air sampling was conducted in the nursing home section of four long term care facilities, three days at each facility (12 days total). Particle concentrations (PM2.5, PM10, Total Particulate matter (TPM), Ultrafine Particles (UFP), temperature, and humidity were measured. Two minute samples were collected during seven Sampling Sessions. Up to nine indoor locations were sampled, representing the various occupied spaces in each nursing home, along with an outside location for comparison. Results of Analysis of Variance (ANOVA) by Facility demonstrated significant differences (p<0.001) in PM concentrations and UFP counts. One Facility had higher particulate concentrations at all Sampling Locations which may include contributions from geographic location, vehicular traffic, or resident clustering. ANOVA by Sampling Location demonstrated significant differences (p<0.001) in PM concentrations and UFP counts. In general, the highest UFP and PM concentrations were seen in the kitchen, satellite kitchen, and hair salon, especially at times when the staff and residents were active in these rooms. Significant differences were seen in UFP counts (Facilities 1 and 3) and PM2.5 (Facility 2) by Sampling Session. The highest concentrations were found for the Sampling Sessions in the mid-morning and mid-afternoon which were during peak times of activity for the residents. Although maximum temperature measurements exceeded ASHRAE winter guidelines, this may be appropriate for older residents who prefer a warmer temperature. While most median particle values were below ASHRAE guidelines, maximum values did exceed occasionally in the hair salon and kitchen at all facilities. Various indoor Sampling Location PM concentrations or UFP counts exceeded the outdoor levels at all four facilities. Although the median PM values did not exceed the ASHRAE standards it is unknown whether older adults may still experience significant health complications with these PM concentrations. In addition staff who spend extended amount of times in the kitchen and hair salon could be exposed to higher levels of PM. IAQ in hospitals and similar environments, such as nursing homes, may require a higher level of care because of the vulnerable population.

Committee:

April Ames, PhD, CIH (Committee Chair); Victoria Steiner, PhD (Committee Member); Akbar-Khanzadeh Farhang, PhD, CIH (Committee Member); Sheryl Milz, PhD, CIH (Committee Member)

Subjects:

Aging; Alternative Medicine; Engineering; Environmental Engineering; Environmental Health; Environmental Science; Environmental Studies; Gerontology; Health; Health Care Management; Health Sciences; Medicine; Occupational Health; Occupational Safety; Public Health; Welfare

Keywords:

Particulate Matter; Nursing Homes; Elderly; Indoor Air Quality; PM; IAQ; ASHRAE; Air Quality; susceptible population; buildings; Aging

Jackson, Eric AlanTowards a Prediction of Landscape Evolution from Chemical Weathering and Soil Production
Master of Science (MS), Wright State University, 2017, Physics
The time evolution of a periodic landscape under the influence of chemical weathering and physical erosion is computed. The model used incorporates weathering and soil production as a flux limited reaction controlled by groundwater flow. Scaling of the flow rate is obtained from a percolation theoretic treatment. The erosion of the soil material produced by this process is modeled by the diffusion of elevation, as consistent with downslope soil transport proportional to the tangent of the angle of the topography, and application of the equation of continuity to surface soil transport. Three initial topographies are examined over a periods of thousands of years and resulting landforms and soil productivity compared. Differences in productivity between these cases are found to occur primarily within a short time span of hundreds of years. Times for propagation of a disturbance in one layer to another are also obtained.

Committee:

Allen Hunt, Ph.D. (Advisor); Jerry Clark, Ph.D. (Committee Member); Thomas Skinner, Ph.D. (Committee Member)

Subjects:

Environmental Science; Physics

Keywords:

soil production; percolation; erosion; diffusion; landscape evolution; groundwater; solute transport

Krichbaum, Steven P.Ecology and Conservation Biology of the North American Wood Turtle (Glyptemys insculpta) in the Central Appalachians
Doctor of Philosophy (PhD), Ohio University, 2018, Biological Sciences (Arts and Sciences)
My study presents information on summer use of terrestrial habitat by IUCN “endangered” North American Wood Turtles (Glyptemys insculpta), sampled over four years at two forested montane sites on the southern periphery of the species’ range in the central Appalachians of Virginia (VA) and West Virginia (WV) USA. The two sites differ in topography, stream size, elevation, and forest composition and structure. I obtained location points for individual turtles during the summer, the period of their most extensive terrestrial roaming. Structural, compositional, and topographical habitat features were measured, counted, or characterized on the ground (e.g., number of canopy trees and identification of herbaceous taxa present) at Wood Turtle locations as well as at paired random points located 23-300m away from each particular turtle location. First, I report and discuss basic morphometric and activity area data of the VA and WV turtles. Chapter two uses a nine-year dataset of adult WV Wood Turtles to estimate population size, population growth rate (lambda), and survivorship with open population Cormack-Jolly-Seber and Pradel models in program MARK. My third chapter assess Wood Turtle thermal ecology by examining three data sets of environmental and turtle temperatures: 1) temperatures in three different microhabitat types (unshaded by ground cover [exposed], under vegetation [UV], under litter [UL]) recorded by iButtons at arrays throughout the two study sites; 2) ground temperatures at the locations of radio-tracked individuals and their paired random points measured within 300 meters and 30 minutes of each other; 3) body temperatures estimated with iButtons attached to the shell bridges of adult Wood Turtles. In the fourth chapter, I examine highly localized conditions resulting from short-term weather patterns and fine-scale microhabitat characteristics by comparing ground-level relative humidity at the locations of radio-tracked Wood Turtles to those at paired random points. I use the GIS-based water balance model developed by Dr. James Dyer to examine landscape conditions (such as water deficit [“DEF”] and actual evapotranspiration [“AET”]) resulting from long-term climate patterns and broad-scale habitat conditions (e.g., topographical aspect and soil types). The final two chapters are the heart of my dissertation. Vegetation was identified, measured, counted, or characterized in plots at 640 locations (394 in VA, 246 in WV), evenly distributed between adult turtle and random points. Importance values for overstory trees = 10cm dbh were calculated in 400m2 plots; herbaceous plant taxa were identified in 400m2 and 1m2 plots; woody seedling taxa were identified in 1 m2 plots; forest types were specified at the 400m2 plot and stand (5-20ha) scales. I used the R program “indicspecies”, paired logistic regression, and classification and regression trees (CART) to analyse these data. Over thirty herbaceous and woody seedling taxa were indicators for Wood Turtle presence at the 400m2 and/or 1m2 scales at the VA and WV study sites. I used a series of conditional logistic regressions to quantify habitat use of Wood Turtles at multiple scales across a range of different forest types. At each of the turtle and random points proportions of ground cover were visually estimated within 1m2 plots to assess microhabitat use; structural, compositional, and topographical habitat features were measured in 400m2 circular plots to capture meso-scale ecological data; and stand scale (5-20ha) designations of forest type and seral stage were used to assess macro-scale habitat use. I found that Wood Turtles showed a preference for specific environmental conditions: older forest sites with relatively more herbaceous ground cover, large woody debris, canopy openness, and turtle-level obscurity, and with gentler slopes and warmer aspects.

Committee:

Willem Roosenburg, Professor (Advisor)

Subjects:

Animals; Ecology; Environmental Science; Forestry; Wildlife Conservation; Wildlife Management; Zoology

Keywords:

habitat selection; turtle population biology; program MARK; forest temperatures; turtle temperatures; forest floor humidity; forest herbaceous flora; tree importance values

Richardson, Bree LaceyHYDROLOGICAL AND BIOGEOCHEMICAL MECHANISMS DRIVING NITROGEN AND PHOSPHORUS RETENTION IN A FRESHWATER ESTUARY
MS, Kent State University, 2018, College of Arts and Sciences / Department of Biological Sciences
Human alterations to the global nitrogen (N) and phosphorus (P) cycles negatively impact ecosystems and threaten human health. Nutrient runoff from agricultural land use practices degrades water quality by stimulating hypoxia (lack of oxygen) and harmful algal blooms. Wetlands are often relied on by humans to provide multiple ecosystem services at a relatively low cost. The objective of this thesis was to better understand the mechanisms driving N and P cycling in Old Woman Creek estuary (OWCE), an unaltered wetland along the coast of Lake Erie. We assessed the seasonal hydrologic influence on nutrient loading to OWCE, estimated an annual mass balance to determine nutrient removal capabilities, determined spatial heterogeneity of N and P removal mechanisms, investigated the vertical distribution of nutrients in surface waters, and determined the potential for wetland sediments to facilitate N and P release. We used daily water quality and hydrologic measurements to calculate complete annual mass balances for water, N, and P for water years 2016 and 2017. We collected water and sediment samples during June 2016, August 2016, April 2017, and August 2017 to assesses the denitrification potential and P storage and conducted a continuous flow-through experiment. The hydrology and seasonal variation of individual wetlands is important to consider when assessing nutrient removal potential. We found that while on the mass balance scale OWCE retains N and P, spatially there is variation where nutrient retention is occurring based on indicators of N and P removal mechanisms, but variation occurred within similar locations demonstrating duel nutrient removal potential. However, sediments have the potential to release N and P in the water column. Biological activity in the wetland may be an important driver in retaining N and P released from the sediment. Overall, nutrient removal in the wetland is controlled by a combination of loading into the wetland, autotroph activity, microbial processes, and temporal variation. Our study demonstrates that OWCE is an efficient wetland in removing nutrients from the water column.

Committee:

Lauren Kinsman-Costello (Advisor); Darron Bade (Committee Member); Christopher Blackwood (Committee Member)

Subjects:

Biogeochemistry; Environmental Science; Water Resource Management

Keywords:

Biogeochemistry, estuary, nitrogen, phosphorus

Semones, Molly CatherineDynamics in the reactivity and photochemical production of hydroxyl radical in treated wastewater effluent and aquatic dissolved organic matter
Doctor of Philosophy, The Ohio State University, 2017, Environmental Science
The hydroxyl radical (HO•) is a photochemically generated species that is important in the attenuation of organic contaminants in sunlit natural surface waters and in advanced oxidation processes (AOPs) used to treat drinking and wastewater. The steady state concentration of HO•, ([HO•]ss), in photochemical systems is typically measured indirectly using probe compounds. In this work, we investigate the use of caffeine as a photochemical probe for the detection of HO• in the presence of dissolved organic matter (DOM) solutions derived from allochthonous and autochthonous precursors using both the first order and initial rates approach to kinetic analysis to determine [HO•]ss in aqueous solution. Values for [HO•]ss are found to agree within a factor of two of values measured using terepthalic acid (TPA), a well-established probe for the detection of HO•, in the identical DOM solutions. Additionally, we find that caffeine is more selective for HO• than previously believed since it does not appear to undergo reaction with long-lived reactive transients as was formerly presumed. The presence of nitrate in wastewater effluent could play an important role in the formation of HO•, and therefore also in the fate of contaminants in sunlit receiving waters. We investigate the interplay between HO• formation derived from both effluent dissolved organic matter (EfOM) and nitrate (NO3-). The assumption of little to no interaction between NO3- and EfOM during HO• production (RHO•), needed to determine the contribution of DOM to hydroxyl radical formation in waters containing NO3- without extracting EfOM from the wastewater, is invalid. We based our findings on measurements of RHO• and [HO•]ss using benzene and caffeine as HO• probes in both whole wastewater effluent and solutions of EfOM isolated by solid phase extraction from the same effluent sample. The RHO• value measured for the isolate in the absence of NO3- (0.074 ± 0.009 (SE) nM s-1) is 1.5 fold higher than that found for bulk, non-isolated EfOM (0.049 ± 0.026 (SE) nM s-1), which was calculated by subtracting the estimated contribution of NO3- to overall HO• production from the RHO• obtained for the Southerly whole wastewater. This difference calculated this way is not significantly different (a=0.05, p=0.39). We find that we are able to reproduce the RHO• found with benzene for Southerly wastewater effluent (0.199 ± 0.022 nM s-1) using a NO3-ROH• curve generated in a Southerly isolate solution (0.178 ± 0.011 nM s-1). Similarly, [HO•]ss values measured in Southerly whole wastewater effluent using caffeine as a probe compound (1.32 ± 0.096 fM) were comparable to measurements made in Southerly EfOM (1.50 ± 0.091 fM). We revise the ratio at which NO3- and DOM contribute equally in solution from the value reported by Vione et al. (2006) of 3.3 x 10-5 [(mol NO3-) (mg-C)-1]) upwards to 8.1 ± 1.5 x 10-5 [(mol NO3-) (mg-C)-1] based on the average of the ratios determined for the three DOM isolates used in this study. Values for [HO•]ss in IHSS isolate solutions and whole wastewater effluent determined by benzene and caffeine are in good agreement, which supports the use of caffeine as a credible HO• probe compound, subject to caveats detailed within this work, in both isolate solutions and whole water containing NO3-. Organic UV-filters are key ingredients found in sunscreens, cosmetics and plastic goods. Concerns have been raised about potential ecological and human health effects of certain organic UV filters that are currently FDA approved for use in the United States. Here, we investigate the photochemical fate of two of these compounds, oxybenzone and sulisobenzone. Both oxybenzone and sulisobenzone have previously been detected in surface waters, seawater, and treated wastewater effluent. Enhanced photodegradation of oxybenzone and sulisobenzone was observed under simulated solar irradiation in solutions of International Humic Substance Society standards (Pony Lake fulvic acid and Suwannee River Natural Organic Matter), filtered wastewater effluent (Southerly Wastewater Treatment Plant in Lockbourne, OH), and Scioto River water (Columbus, OH). Quenching experiments with isopropanol revealed that the main pathway for degradation appears to be reaction with the hydroxyl radical (HO•). Observed degradation rates were 2-3 times slower than estimates calculated using literature reported second-order rate constants and measured hydroxyl radical steady-state concentrations for SRNOM, PLFA and Scioto waters. The Southerly sample, however, exhibited nearly identical expected and observed rate constants, which we take to indicate the presence of unidentified reactive species that can react with oxybenzone and sulisobenzone. Values obtained in this work were used to calculate second-order rate constants for oxybenzone and sulisobenzone with the hydroxyl radical, as well as to estimate environmental half-lives for these compounds. Near surface 24-hour averaged half-lives of 3.0 and 4.0 days were calculated for oxybenzone and sulisobenzone,respectively. When extrapolated to an environmentally representative water column, these same 24-hour averaged half-lives increased to 2.4 and 3.5 years, respectively.

Committee:

Yu-Ping Chin (Advisor); Terry Gustafson (Committee Member); Roman Lanno (Committee Member); John Lenhart (Committee Member)

Subjects:

Environmental Science

Keywords:

Photochemistry; hydroxyl radical; nitrate; dissolved organic matter; DOM; sunscreen; oxybenzone; sulisobenzone

Brooker, Michael RWater Contaminants of the Lake Erie Watershed
Doctor of Philosophy, The Ohio State University, 2018, Environmental Science
Streams and rivers act as conduits, transporting pollutants from their sources to downstream drainage basins. The Lake Erie watershed is dominated by agricultural land use. As a result, there are many concerns over pollution sourced from upstream agroecosystems. Among the principle issues in the region, phosphorus and other nutrient pollutants have been faulted for stimulating and/or supporting the frequency and magnitude of recurrent harmful algal blooms occurring in the western Lake Erie basin. Phosphorus pollution originates from a variety of point and nonpoint sources, however specific estimates of individual source contributions have proven elusive. Better distinguishing between the sources of pollution, as well as an improved ability to track transport through the watershed is essential for managing nutrient loads. One promising and new approach to elucidating source contaminants is the organic phosphorus fraction of dissolved orgnaic matter (DOM). Point and non point sources may exhibit unique DOM or dissolved organic phosphorus (DOP) signatures, tha allows for the differentation between sources, either through signature analysis or the application of marker molecules. Here, electrospray ionization Fourier-transform mass spectrometry (ESI FT-ICR-MS) was used to analyze the DOM and DOP signatures from nutrient pollution sources in the Lake Erie watershed. Three marker compounds were distinct to sources were proposed for use in tracking the presence of source contamination. From this source signature analysis, differences in DOM was next evaluated along a mixing profile for a Lake Erie tributary. The ability to detect DOM formulae upstream to downstream sites was assessed. Compounds detected in higher abundane upstream were more likely to be detected at downstream locations. The mass spectra signals of merging branches appeared to be mixed linearly into several confluence points. In addition to nutrient sources influencing Lake Erie water quality, there are concerns over the introduction of antibiotics to the drainage basin from use in regional agricultural operations. Metals and antibiotics are known to co-select for antibiotic resistance genes in agroecosystems, suggesting two possible causes in the development of resistant microbial communities. Here, sediments from agricultural dominated channels were analyzed for antibiotics, metals, and relevant functional microbial genes. Although few antibiotics were detected in the sediments, some metals were found at elevated levels. Antibiotic resistance genes were among the most abundant and diverse set of genes detected using an environmental microbial functional microarray technology, Geochip. Metal homeostasis genes and the intI integrase gene, indicative of the potential for horizonal gene transfer, were also abundant across samples. These results highlight the prevalance of antibiotic resistant genes in sediments draining to the Lake Erie ecosystem, with implications for downstream transport from agricultural sources.

Committee:

Paula Mouser (Advisor); Jon Witter (Advisor); Gil Bohrer (Committee Member); Virginia Rich (Committee Member)

Subjects:

Environmental Science

Keywords:

molecular biology analysis; dissolved organic matter; dissolved organic phosphorus; ESI FT-ICR-MS; antibiotic resistance; agriculture; harmful algal blooms; Lake Erie

Liu, KunImproved Onsite Wastewater Disinfection and Nutrient Removal for Safe Discharge and Reuse
Doctor of Philosophy, The Ohio State University, 2017, Environmental Science
For onsite wastewater reuse or discharge, fixed media biofilters provide high treatment efficiency with relatively low cost and maintenance. However, these biofilters are not designed to provide disinfection or remove nutrients. Advanced treatment processes are needed to reduce public health and environmental risks before reuse or discharge into surface water. The objectives of this study were to improve onsite wastewater disinfection, to enhance cold weather ammonia removal, and to develop an advanced natural nutrient removal system. The existing disinfection systems used for onsite wastewater treatment are flow-through UV and chlorine systems. They both have disadvantages. Flow-through systems using UV lamps have continuous lamp operation with fluctuating flows. Mineral and humic substances foul the lamps and solids accumulate in the disinfection chambers. Flow-through chlorine tablet systems introduce the disinfectant as it dissolves in the flowing water. Variations in flow rate results in inconsistent tablet dissolution and chlorine dosing. Batch UV and chlorine disinfection proved to overcome the drawbacks of conventional systems. The batch UV system shortened daily operation time by two-thirds and eliminated solids settling. The batch design reduced lamp fouling and maintenance while sustaining high disinfection effectiveness. Batch chlorine system using a slow-release chlorine agent provided precise control of chlorine dose, allowed for longer contact time and reduced dosing frequency. The 9- and 6-months field tests for UV and chlorine batch systems showed their effectiveness and reliability. This study showed that batch UV and chlorine systems are both improved alternative onsite disinfection systems. Cold temperature often reduces ammonia removal efficiency in wastewater treatment systems. Improving ammonia removal by warming biofilters in cold weather has not been tested yet. This study investigated two methods to warm biofilters: covering the biofilter surface with polyethylene films and covering the biofilter with insulation in a greenhouse. The results showed that both treatments significantly increased the biofilter temperature by 4 °C on average. However, ammonia removal was not improved correspondingly. Instead, both warming methods might pose negative impacts on biofilters. Anaerobic conditions were established within the covered filters which resulted in loss of ammonia removal capability. The ammonia removal performance of sand biofilter might be affected by many other factors other than just temperature. Biofilter effluent nitrogen and phosphorus are plant nutrient. An advanced nutrient removal system was developed using a hydroponic floating bed systems with perennial ryegrass. Hydroponic floats and floating beds were designed and tested to solve the issues of consistent seed germination and algae control. The results showed that customized opaque floats and shaded rack with misters offered even grass seeds germination with no surface algae growth. The customized floats that filled the hydroponic beds also insured algae control in the treated effluent. This simple system allowed the plants to grow optimally and develop a healthy root mat under the hydroponic floats, which significantly enhanced the nutrient removal efficiency. Such floating bed systems could alleviate the environmental risk of onsite wastewater discharge and produce an easily harvested, usable crop while reducing the nutrient load into surface water.

Committee:

Karen Mancl (Advisor); Jiyoung Lee (Committee Member); Olli Tuovinen (Committee Member); Peter Ling (Committee Member)

Subjects:

Environmental Science

Whalen, Kevin ChristopherA map system to disseminate national science on forests for the creation of regional tree planting prioritization plans
MS, Kent State University, 2017, College of Arts and Sciences / Department of Computer Science
In the United States, urban forestry efforts are sustained through efforts from individuals, businesses, philanthropic organizations, and government agencies across local, state, and national levels. The i-Tree Tools suite of software promotes the use of, peer-reviewed science to explain the benefits that trees provide in a method intended for the general public. This thesis shares the computer-specific knowledge collected during the design, implementation, and continued expansion of i-Tree Landscape. The i-Tree Landscape application is a web-browser based, online, geographic information system, referred to as a web-GIS app. The "pages" of the web-app are part of a system of software libraries and services, along with dedicated hardware, which were specifically researched, compared, selected, and optimally configured for their roles in supporting the system as a whole. This work will also briefly touch upon the open source libraries and services running in the Landscape system, as well as, some of the decisions they influenced with acquiring hardware to support its deployment. Delivering the data and formulas associated with the benefits of trees for the entire geographic area of the United States becomes difficult over the internet, especially when it must be achieved via a non-expert interface. To manage this, the flow of the application is separated into five, non-sequential steps, prefixed with a landing page, and postfixed with a publishable report. This partitioning helps with code responsibility separation, as well. In addition to producing a tailorable report for describing the benefits of trees, the primary purpose of the application is to help prioritize tree planting efforts. This is well needed by foresters to help allocate for popular practice of mass tree plantings. The planning is done via a customizable model utilizing nearly all of the possible attributes as weighting options. The regional aggregations for this are available to users through nine boundary layers, most notably including counties, block groups, and watersheds. The research supporting the data on trees is from working directly with the authors of peer-reviewed research from the United States Department of Agriculture Forest Service laboring at the Northern Research Station at the College of Environmental Science and Forestry in Syracuse, New York. i-Tree Landscape has succeeded in becoming a science dissemination facility, by the use of information visualization, with the purpose of making decisions that promote urban forestry stewardship through modern web-GIS, and data processing techniques.

Committee:

Cheng-Chang Lu, PhD (Advisor); Austin Melton, PhD (Committee Member); Gokarna Sharma, PhD (Committee Member)

Subjects:

Computer Science; Ecology; Environmental Science; Geography; Urban Forestry; Urban Planning

Keywords:

budget national map processing; geographic information system; GIS; national land cover; forestry; tree planting prioritization; GDAL; GEOS; GeoServer; PostGIS; JTS; Open Geospatial Consortium; OGC; Open Source Geospatial Foundation; OSGeo;

Whitehead, Hannah RVarroa mite management among small-scale beekeepers: Characterizing factors that affect IPM adoption, and exploring drone brood removal as an IPM tool
Master of Science, The Ohio State University, 2017, Environmental Science
Varroa mites (Varroa destructor) are the most damaging pest in modern beekeeping, and have been linked with elevated levels of colony loss. Experts increasingly recommend an integrated pest management (IPM) strategy to manage Varroa, which incorporates both preventative and therapeutic controls. However, Varroa IPM is complicated and knowledge-intensive. Small-scale beekeepers in particular seem to have difficulty adopting effective Varroa control strategies, and suffer especially high rates of colony loss. This study took an interdisciplinary approach to understanding the adoption of Varroa IPM among small-scale beekeepers. First, I used surveys and interviews to characterize mite management strategies among Ohio small-scale beekeepers, and to explore the effect of experience and risk perception on behavior. Second, as a case study, I took a closer look at the efficacy and adoption of one complex IPM tool – drone brood removal (DBR) – through interviews, surveys, and an on-farm trial. Overall, I found no relationship between beekeeping experience and mite management strategies, but sampling (risk perception) was associated with the use of “soft” miticides (organic acids/essential oils) and DBR. I also found that most beekeepers who used DBR combined it with drone sampling (adjusting DBR based on sampled mite levels), and that labor was the biggest barrier to DBR use. In the on-farm trial, DBR significantly reduced mites in year one but not year two. These results suggest that mite management failures among small-scale beekeepers are not due to inexperience and may indicate a broader communication breakdown. They also suggest that risk perception – beekeepers’ understanding that they even have mites – may be a key factor driving adoption of mite management practices. Finally, they point to the fact that DBR is already being used in nuanced ways as a combined management and sampling strategy. They suggest that DBR is not a silver bullet, but can be an effective tool to reduce mites if used consistently, intensively, and in combination with other management tactics.

Committee:

Casey Hoy, Ph.D. (Advisor); Reed Johnson, Ph.D. (Committee Member); Anna Willow, Ph.D. (Committee Member)

Subjects:

Agriculture; Entomology; Environmental Science

Keywords:

varroa mite; mite management; mite sampling; drone brood removal; IPM; sustainable agriculture; beekeeping; farmer decision-making; risk perception; honey bee

Cummins, Adam RLocal Solid Waste Management Planning in Ohio: A Case Study of Adams-Clermont Solid Waste District
Master of Environmental Science, Miami University, 2017, Environmental Sciences
This report provides historical context on how solid waste management has evolved in the United States, particularly in Ohio, and identifies the key federal and state legislation adopted to address solid waste management challenges experienced in the mid and late 1900s. Furthermore, it describes the regulatory framework for the solid waste management planning process both at the state and local levels in Ohio. Finally, it summarizes my role as an intern, describes the challenges I experienced while preparing the Adams-Clermont Solid Waste Management Plan, identifies opportunities to those challenges through legislative and policy recommendations, and describes several non-legislative solutions I subsequently implemented as a solid waste planner at the Ohio Environmental Protection Agency.

Committee:

Suzanne Zazycki (Advisor)

Subjects:

Environmental Law; Environmental Science; Environmental Studies; Urban Planning

Keywords:

solid waste, solid waste management, solid waste management planning, Ohio solid waste management, solid waste management district

Fyffe, Deanna LynneMethods to Monitor Lake Erie's Harmful Algal Blooms: A Fellowship with the Cooperative Institute for Great Lakes Research
Master of Environmental Science, Miami University, 2017, Environmental Sciences
To fulfill the professional experience requirement for a Master of Environmental Science degree at Miami University, I completed a fellowship with the Cooperative Institute for Great Lakes Research (CIGLR). My work involved investigating data trends of recent Lake Erie harmful algal blooms and potential monitoring methods. Data trends revealed monitoring stations closest to the mouth of the Maumee River had the highest average cyanobacteria concentrations. Bloom biomass distribution tended to favor the surface of the water column but was likely influenced by wind speed in 2016 and 2017. I also compared chlorophyll-a data from a CIGLR-owned bbe FluoroProbe to laboratory extraction data. The bbe FluoroProbe provided consistent results when used in the field and in the laboratory, but generally identified less chlorophyll-a than pigment extraction methods. Additionally, I performed field, laboratory, and analytical work to evaluate commercial in situ fluorometers. Due to proprietary reasons, the individual fluorometer data could not be presented in this report. I provided an example field deployment evaluation for the YSI EXO2 Multiparameter Sonde, a CIGLR-owned fluorometer that was used during the field tests for ancillary data. The EXO2 ultimately had low accuracy when compared to traditional laboratory methods, but both methods produced similar data trends.

Committee:

Suzanne Zazycki, JD (Advisor); Bartosz Grudzinski, PhD (Committee Member); Vanni Michael, PhD (Committee Member)

Subjects:

Aquatic Sciences; Environmental Health; Environmental Science; Environmental Studies; Freshwater Ecology; Microbiology; Water Resource Management

Keywords:

Lake Erie, Great Lakes, harmful algal bloom, HAB, water quality, in situ, fluorometer, cyanobacteria, biomass, microcystis, chlorophyll, phycocyanin, pigment, research, laboratory, EXO2, FluoroProbe, NOAA, GLERL, CIGLR, monitoring

Hartung, Erik WalterAging bioretention cells: Do they still function to improve water quality?
MS, Kent State University, College of Arts and Sciences / Department of Biological Sciences
Stormwater runoff from impervious surfaces transports a variety of pollutants to freshwaters via urban drainage pathways. Bioretention cells are a stormwater control measure being widely adopted with the goal of receiving, infiltrating and improving quality of stormwater before it enters surface waters. However, there are uncertainties about the spatial distribution and concentration of toxic metals that accumulate and concerns about changes in hydrologic function of aging bioretention cells. This study sought to address those concerns using a survey of 26 parking lot bioretention cells in the greater Cleveland area, ranging in age from <1 to 7 years of service. Bioretention cells were found to accumulate Cu, Pb and Zn in their media through time, but the distribution of these toxic metal pollutants was homogenous with respect to depth and distance from the stormwater flowpath. The concentration of metals in bioretention cell media were well below EPA soil contamination thresholds. Bioretention cells were found to have reduced hydraulic conductivity as they age, but bioretention cells less than eight years old still met EPA standards for hydrologic function. Therefore, regular maintenance of bioretention cells may be needed to remove sediment and improve hydrologic function, but no remediation would be needed for toxic metals. It is expected that bioretention cells function to capture, infiltrate and remove pollutants from stormwater runoff, leading to water quality improvement downstream. However, there is a lack of knowledge regarding active bioretention cells' ability to perform these functions over the long-term. This study aimed to elucidate the function of bioretention cells for removal of toxic metal pollutants (Cu, Pb and Zn) from runoff over 7 years of service time. This study also sought to address the effects road salt may have on bioretention's ability to filter or retain toxic metal pollutants from stormwater. Using leach columns constructed with media from 19 active bioretention cells ranging in age from <1 to seven years old, this study found that age is not a good predictor of bioretention cell functioning for metal removal. Bioretention cells were found to function well for removing low concentrations of metals from stormwater, but had reduced functioning for removal of high concentrations of metals. Bioretention cells' ability to remove metals from stormwater was found to be similar at different locations within the cells. Road salt was found to reduce the functioning of aged bioretention cells (7 years of service) for Pb and Zn removal from stormwater, but had no effect on functioning for Cu removal. Bioretention cells less than eight years in age were found to be able to reduce the concentration of metals in stormwater to concentrations below EPA thresholds for freshwater, but road salt may reduce bioretention's ability to reduce the concentration of Pb and Zn in stormwater.

Committee:

David Costello (Advisor)

Subjects:

Aquatic Sciences; Biogeochemistry; Biology; Ecology; Environmental Engineering; Environmental Management; Environmental Science; Environmental Studies; Freshwater Ecology; Hydrologic Sciences; Hydrology; Land Use Planning; Natural Resource Management; Water Resource Management

Yu, FangModeling of Soil Formation on The Basis of Chemical Weathering: Applications From Percolation Theory
Doctor of Philosophy (PhD), Wright State University, 2018, Environmental Sciences PhD
The concept of soil formation has been studied since the beginning of 19th century. However, until recently, there has been little concrete progress on developing an analytical result to relate soil depth or quality to measurable variables that represent the five soil-forming factors including time, parent material, topography, climate, and organisms. It has become increasingly clear that soil formation rates are closely related to chemical weathering rates. In this dissertation, we propose a theoretical approach to model soil formation process within the theoretical framework of percolation theory, which has been shown to successfully predict solute transport in heterogeneous media. From percolation theory, solute transport rate does not equal to flow rate beyond the length scale of a typical pore size, as is the case in Gaussian solute transport. Rather, it diminishes in accord with heavy-tailed solute arrival time distributions as it travels. The basis of our model relies on the hypothesis that the chemical weathering of bedrock is simultaneously the limiting factor for soil formation and most strongly limited by solute transport in porous media. To test the hypothesis, we propose a revised method to calculate Damkohler number within the same theoretical framework to evaluate the relevant importance of solute transport in limiting chemical weathering, and results imply that chemical weathering is nearly always solute transport-limited in natural media. We then examine the proposed models by comparing predictions with field data across a wide range of climatic conditions, as well as at steep topography. Results show good agreement between predictions and field observations. We also present two applications of the proposed model to geomorphology to examine the local steady-state assumption of soil and to distinguish steady and stochastic erosion process in threshold landscapes. The applications demonstrate the potential to adopt our model into geomorphological models such as landscape evolution models, and landsliding models to predict shallow landslides.

Committee:

Allen Hunt, Ph.D. (Advisor); Christopher Barton, Ph.D. (Committee Member); Mark Goltz, Ph.D. (Committee Member); W. Berry Lyons, Ph.D. (Committee Member); Thomas Skinner, Ph.D. (Committee Member)

Subjects:

Environmental Science; Geochemistry; Geomorphology

Keywords:

soil formation; chemical weathering; percolation; percolation theory

Paulose, HannaChoosing What is Right, Knowing What You Choose, and the Gap in Between: Decoding Food Sustainability
Doctor of Philosophy, The Ohio State University, 2017, Consumer Sciences
This dissertation examines consumer’s perceptions of `sustainability’ or `greenness’ and its various dimensions in the service context. Even though environmental sustainability has received significant attention in the industry, a comprehensive measurement model to assess consumer’s understanding or perceptions of sustainability in the service sector is yet to be developed. As a result, it is difficult to assess the level of consensus between consumers and producers regarding what is sustainable services. This study aims to identify various dimensions of `Perceived Service Greenness (PSG)’ in the restaurant sector and develop a scale to accurately measure consumer perceptions of restaurant sustainability. In addition, the study also aims to examine how different dimensions of PSG influence consumers’ evaluation of and behavioral intentions regarding restaurants. The research context for this dissertation is the restaurant sector-one of the dominant service sectors worldwide. The data for the research come mainly from three different studies. The first study adopts a mixed method approach to develop the scale for PSG. The second study validates the PSG scale using an online survey. In the third study, a scenario based experiment, developed based on the three dimensions of PSG identified in study 2, to examine how PSG affects consumers’ evaluation of the restaurant as well as their behavioral intentions. The three dimensions of PSG emerging from the studies – Product Greenness, Process Greenness and Servicescape greenness – suggest that consumer perceptions of sustainability need to be examined as a multi-dimensional construct to correctly understand its effect on consumer behavior, and a better understanding of this relationship is crucial, for no business can be sustainable in the long run if it does not sell.

Committee:

Milos Bujisic, Dr. (Advisor); Robert Scharff, Dr. (Committee Co-Chair); Kandampully Jay, Dr. (Committee Member); Chandrasekaran Aravind, Dr. (Committee Member)

Subjects:

Environmental Science; Social Research

Keywords:

Greenness, Sustainability

Fair, Heather LynneEcology of aquatic insects in monsoonal temperate glacier streams of Southeast Tibet: A departure from the conceptual model
Doctor of Philosophy, The Ohio State University, 2017, Environmental Science

The cryosphere is shrinking as a result of climate change. Mountain glaciers, a key component of the cryosphere, serve as headwaters to glacier meltwater streams which support communities of stenothermic organisms. The Tibetan plateau is known as "the Third Pole" for its high number of glaciers, yet very few scientific papers have been published on aquatic invertebrate ecology of glacier-fed streams in the region. On the edges of the Tibetan Plateau in Southeast Tibet's Hengduan mountains, monsoonal temperate glaciers extend well below the treeline as valley glaciers, and are perhaps the most endangered cryosphere-dominated streams in the world due to their low latitudes and altitudes, which makes them sensitive to atmospheric temperature changes. The glaciated headwaters of the Mekong and Yangtze Rivers comprise a small fraction of the annual river discharge, yet at a local scale provide glacial meltwater that supports endemic and potentially rare species.

Water temperature and channel stability differ between seasons due to the torrential flow from glacial meltwater during the summer melt season. The Milner & Petts (M&P) model of macroinvertebrate presence in glacier streams was based on the environmental factors of water temperature and channel stability during the summer melt season. In low temperature water close to the glacier, the macroinvertebrate communities are generally limited to Diamesinae chironomids, and further downstream more taxa are found where water temperature and channel stability increase. Therefore, temperature and channel stability are examined as potential limiting factors on the distribution of invertebrate communities, with the goal to compare the insect communities in Southeastern Tibet's glacier-fed streams with the widely-accepted M&P model of invertebrate community structure.

Since discharge and hydrology may influence invertebrate distribution in glacier streams, hydraulic characteristics and invertebrate communities in six microhabitats (pool, riffle, run, step-run, rapid, and step-rapid) were examined over three seasons in the Mingyong Glacier stream. This is the first known study to examine hydraulics at the microhabitat level in glacier streams, and to compare microhabitats by season. Certain hydrologic characteristics have been found to trap and retain leaf litter at different rates, with backwater areas having the greatest trapping efficiency even in high discharge. Moreover, microhabitats with turbulent water entrain oxygen from the atmosphere which can lead to greater biomass growth. Microhabitats with larger substrate create hydrologic refugia for insects, and higher velocity microhabitats tend to have larger boulder substrate. Therefore it was hypothesized that in the Mingyong Glacier mainstem rapids and step-rapids with greater water velocities and velocity ranges would support greater aquatic insect species richness and abundance.

In addition to hydraulics and environmental variables, the salinity tolerance of glacier stoneflies was examined to partially study the research question, "will metakryal zone insects from glacier streams adapt to groundwater stream salinity levels once the glaciers are gone"? Moreover, the morphological changes of their chloride cells following exposure to waters of differing salinity were quantified by using scanning electron microscopy images. The survivorship of stoneflies from upstream glacial meltwater sites was compared with stoneflies from downstream glacial meltwater sites to salinity treatments.

The ecological result of this research is a clear departure from the accepted M&P glacier stream model where temperature and channel stability are suggested to determine aquatic invertebrate presence in glacier streams. Temperature and channel stability did not exhibit a relationship with species presence, richness, or abundance in Southeast Tibet’s temperate glacier streams during the summer melt season. There were fourteen taxa in addition to Diamesinae in the metakryal zones where the Tmax temperature remains <2oC all year. This is contrary to almost all other studies of glacier streams. The results suggest that other factors such as the mass elevation effect (MEE) of the mountain range, glacier and stream size, winter water temperatures, elevational position of the glacier, ice/snow coverage, and position of the glacier tongue beneath the treeline could be as important in these systems as water temperature and channel stability. In addition, the fact that water is perennially flowing from beneath the glaciers could be a result of the position of the snout beneath the mountain range’s atmospheric zero degree isotherm which results in the monsoonal temperate glaciers falling in the categories of warm-based/wet-based glaciers. The fact that the stream does not freeze could be a major reason for the departure from the model, as many of the streams that were in agreement with the model were located at higher latitudes and in alpine zones (above the treeline) therefore more likely to be above the respective mountain range atmospheric zero degree isotherm where the glacier beds and streams are more likely to freeze during the winter. However, very little is published regarding the conditions of glacier metakryal zones during the winter season.

The results of the study on hydraulic characteristics suggest that rapids, as microhabitats with the highest water velocities and water velocity ranges, trap and retain more organic carbon than pools and riffles, with runs also containing significantly greater organic carbon than riffles. Overall taxa abundance was greatest in runs, which were significantly greater than riffles and pools. This suggests that in glacier-fed streams, the higher velocity microhabitats may be important habitats to examine invertebrate ecology in order to attain representative abundance of taxa in streams.

Chloroperlidae were located furthest from the glacier source, and survived for the longest time in the higher salinity experimental treatments (0.95% and 1.2% NaCl). However, the lethal toxicity of salinity (LC50) to Taeniopterygidae, Nemouridae, and Chloroperlidae were not different, suggesting that naturally-occurring salinities in these mountain stream waters may be in a range tolerable to metakryal stoneflies. Changes in morphology of chloride and caviform cells on Chloroperlidae and caviform cells on Taeniopterygidae occurred as predicted in an inverse manner with salinity. This is the first study that has observed a morphological response from caviform cells, connecting them with an osmoregulatory function.

The results of this research indicate a major departure from the established M&P model of glacier macroinvertebrate community structure. The results suggest that a modified model may be appropriate for glacier-fed streams in the monsoonal temperate region where glacier tongues extend far beneath the extremely high treeline in v-shaped valleys at relatively low altitudes. One reason for the departure may be the perennial nature of the streams under temperate wet-based glaciers which have water present throughout the ice mass. Therefore it would be appropriate to examine winter metakryal conditions in glacier-fed streams in agreement with the M&P model to understand if the streams are intermittent, impacted by surface ice, or freeze solid. Hydraulic and substrate characteristics in this study have an influence on the presence of carbon and invertebrate abundance. Habitats with higher water velocity and potential hidden backwaters support a greater abundance of certain taxa. Hydraulic characteristics and ice presence during the winter could be the two of the major reasons for the difference between the M&P model and this study, so it is suggested that year round hydraulic characteristics be examined in other glacier streams.

Committee:

Lanno Lanno, Dr. (Advisor); David Denlinger, Dr. (Committee Member); Richard Moore, Dr. (Committee Member); Donald Dean, Dr. (Committee Member)

Subjects:

Environmental Science

Keywords:

glacial meltwater; glacier streams; climate change; aquatic ecology; metakryal; Plecoptera; osmoregulation; Southeast Tibet; temperate monsoonal; hydraulic microhabitats; salinity; conductivity; lc50; chloride cells

Conte, Elise RAPPLICATIONS OF ISOTOPES TO MAGMATIC PROCESSES, ERUPTION AGES, AND NUCLEAR FORENSICS
Doctor of Philosophy, Miami University, 2017, Geology & Environmental Earth Science
This dissertation comprises four studies that apply radiogenic isotopes and 14C as primary tools to investigate problems in igneous petrology and environmental contamination. Two studies utilize uranium (U) isotopes to investigate U contamination related to the former Fernald Feed Materials Production Center (FFMPC) in southwest Ohio. Two other studies utilize Sr, Nd, Pb isotopes, U-series disequilibria and 14C to assess the magmatic evolution and timing of explosive eruptions of Sete Cidades volcano, Sao Miguel, Azores. Two studies examine the utility of tree bark for resolving the areal extent of atmospheric U contamination, using several locations in southwest Ohio that processed U. U concentrations up to ~400 times local background levels, along with progressively more depleted and enriched 235U/238U and higher 236U/238U as the FFMPC is approached, demonstrate the presence of anthropogenic U in the environment, with the minor isotope 236U serving as the most sensitive tracer. Atmospheric dispersal models demonstrate that a 5 um U-rich particle can be transported ~38 km from the FFMPC, providing a mechanism for the non-natural isotopic 236U/238U observed in Hamilton and Oxford, OH. Scanning electron microscopy revealed U-rich particles in tree bark within 1-3 km of the FFMPC. Two studies evaluate the petrogenetic processes and timescales associated with the P1-P17 deposits at Sete Cidades volcano. One study presents the first detailed petrographic, geochemical, and isotopic analyses of the Sete Cidades P1-17 eruptive products, and demonstrates that trachyte pumices from P1-P17 are primarily derived through fractional crystallization of a common parental magma, involving discrete batches of magma following distinct fractionation paths. Isotopic variations among whole rock, sanidine, and glass require the presence of xenocrystic sanidine and assimilation of small degree non-modal, partial melt of syenite wall rock similar to Sete Cidades xenoliths. The second of these studies aimed to better constrain the eruptive timing and the impact of volcanic outgassing on 14C ages. 14C data from paleosols in the P1-P17 eruptive sequence were compared to maximum ages from 226Ra-230Th disequilibria in pumices. We present the first age constraints for the P1 and P8 deposits, and further constrain the age of the P17 deposit. 14C data from modern terrestrial gastropods demonstrates the current contribution of volcanic degassing to 14C ages near volcanic centers. New ages constrain the average eruptive recurrence interval for the P1-P17 deposits at ~220 years. Together these four studies highlight the applicability of isotopic tools to a wide variety of earth systems and scenarios.

Committee:

Elisabeth Widom (Advisor); Claire McLeod (Committee Member); John Rakovan (Committee Member); Paul Tomascak (Committee Member); William Renwick (Committee Member)

Subjects:

Atmospheric Sciences; Environmental Geology; Environmental Science; Environmental Studies; Geochemistry; Geology

Keywords:

Isotope; Nuclear forensics; Environmental contamination; Fernald; Tree bark; Azores; Sete Cidades volcano; Volcanic ages; Paleosol; Gastropod; Carbon-14; U-series disequlibria

Del Valle, Lemuel AlejandroWater Quality Internship with the Ohio Environmental Protection Agency
Master of Environmental Science, Miami University, 2016, Environmental Sciences
During the summer of 2015 I had the opportunity to intern at the Ohio Environmental Protection Agency. I worked in the Central District Office in the Division of Surface Water in Columbus, Ohio. My responsibilities were focused around water quality monitoring of various lakes and streams within the state. Lakes sampled included Buckeye Lake, Grand Lake St. Marys, other lakes within the Ohio State Parks system, and drinking water reservoirs. Streams were sampled for varying projects including ambient water quality sampling. The other part of my internship dealt with storm water inspections at construction sites within the Central EPA District. Inspections determined compliance with the general construction permit. This meant assessing sediment and erosion controls and how these controls were implemented for each site. The various types of water quality monitoring will be used to address pressing water quality issues such as nutrient loading and harmful algal blooms, wastewater discharge, and sediment pollution.

Committee:

Sarah Dumyahn, Dr. (Committee Chair)

Subjects:

Environmental Science; Limnology; Water Resource Management

Keywords:

Ohio Environmental Protection Agency; Harmful Algal Blooms; Internship; Division of Surface Water; Water Quality; Lake Sampling

Evert, Mary HInfluence of NOM Molecular Characteristic on Uranium Cycling in a Catchment
Master of Science, The Ohio State University, 2015, Environmental Science
Long-term stewardship of remediated sites relies on the sequestration capability of sediments to retain contaminants, such as uranium (U) over many decades. Natural organic matter (NOM) in the form of detritus, microbial biomass, or metabolites may interact with aqueous and soil-bound U, potentially re-solubilizing it into the water column under certain redox conditions or conversely, enhancing its precipitation through increased electron shuttling activities by microbes. While the influence of NOM on U dissolution process has been investigated from a bulk chemical standpoint (e.g. humic versus fulvic acids; hydrophobic versus hydrophilic compounds), it is not fully understood how NOM form and structure influences U sequestration and microbial activity. The use of Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS) with electrospray ionization (ESI) allows a molecular scale characterization of NOM from complex systems, such as freshwater aquifers. The studies described here are investigating NOM signatures from a U-contaminated aquifer in Rifle, CO and its influence on the system biogeochemistry. Samples taken from seven hydrologic locations show different peaks and heteroatom abundance that relate to their redox condition, with oxygen rich signatures from the Colorado River and other shallow groundwater sources compared with more sulfur rich signatures in chemically reduced zones from deeper groundwater. Acetate and extracted dissolved organic matter (DOM) were amended to sediments and groundwater to assess changes in U and DOM molecular form. Microcosms stimulated with DOM showed similar overall DOC loss and U reduction to other amendments (acetate), but resulted in distinct DOM changes, which may be attributed to abiotic interactions between solutions, sediments, and DOM stimulants. These findings have important implications on U mobility and long term site stewardship of U contaminated remediation sites.

Committee:

Paula Mouser (Advisor); John Lenhart (Advisor); Yu-Ping Chin (Committee Member)

Subjects:

Environmental Science

Hariharan, JananiPredictive Functional Profiling of Soil Microbes under Different Tillages and Crop Rotations in Ohio
Master of Science, The Ohio State University, 2015, Environmental Science
Food production and security is dependent on maintaining soil health and quality. Thus, the emphasis on sustainable and healthy soil function is a top priority for scientists and land managers. One of the most important factors that influences soil function is the microbial community. Recent advances have allowed us to quantify more accurately the composition of such communities, but there is still a knowledge gap with regard to the contribution of microorganisms to various processes occurring in the soil. Understanding this will facilitate the development of healthier agroecosystems. In this thesis, a predictive functional approach is used to elucidate bacterial species–function relationships. Bacterial community profiles were compared across two tillage systems and two crop rotations in Northern Ohio (Wooster and Hoytville). 16S rRNA gene-targeted sequencing was performed and the raw data obtained were filtered, denoised and processed using QIIME. Open-reference OTU picking and taxonomic assignment was performed using the Greengenes database. I then used a computational approach called PICRUSt (Phylogenetic Investigation of Communities by Reconstruction of Unobserved States) to predict metagenomes and the most likely functions performed by individual species of bacteria. Sequence analysis reveals a large number of unidentified OTUs, which is consistent with our expectations of the soil ecosystem. Comparison of sequencing data from different platforms indicates that the dataset generated using Illumina sequencing provided better hits with the reference database than pyrosequencing, and was associated with a greater number of putative soil bacterial functions. PICRUSt allows an estimation of the level of involvement each OTU has with a specific gene function, which enables comparisons to be made across bacterial species and treatment conditions. Predicted functions of the bacterial community revealed a large number of proteins connected with metabolism and maintenance of natural organic molecules in soil as well as enzymes related to degradation of xenobiotics. Using this approach, I was also able to map specific OTUs to their functional potential. Bacterial enzymes implicated in the cycling of nitrogen, sulfur, carbon and methane through the soil were examined, as were enzymes that catalyzed the oxidative degradation of hydrocarbon compounds that are considered soil pollutants. Specialized groups of bacteria were linked to functions like nitrogen fixation and degradation of compounds like atrazine and chlorohydrocarbons. A broader range of OTUs was found to contain genes for carbon utilization and sulfur metabolism. These predictions are supported by previous ecological studies. There were other OTU-function relationships predicted in these studies that are novel and could be valuable in identifying commercially important microorganisms. These leads will require experimental validation. A clear difference was seen between the no-till and plow-till treatments, with no-till being functionally enriched for most major nutrient cycles. No such differences were observed between the different crop rotations. Proteobacteria, Actinobacteria and Acidobacteria were some of the most abundant phyla found in these soil samples, along with Nitrospirae, and Bacteroidetes. I concluded that long-term and continuous application of different tillage systems, and to a lesser extent crop rotation, result in unique bacterial communities that affect the overall functioning of the soil.

Committee:

Warren Dick (Advisor); Parwinder Grewal (Advisor); Margaret Staton (Committee Member)

Subjects:

Agriculture; Biogeochemistry; Bioinformatics; Ecology; Environmental Science; Microbiology; Soil Sciences

Keywords:

PICRUSt; soil metagenomics; soil bacteria; soil function; nutrient cycling

Malpass, Jennifer SEffects of food and vegetation on breeding birds and nest predators in the suburban matrix
Doctor of Philosophy, The Ohio State University, 2015, Environment and Natural Resources
The expansion of urbanization globally has prompted scientists to examine the effects of human developments on wildlife communities, often using birds as a focal taxa. My research investigates population and community-level consequences of anthropogenic food and vegetation resources in the suburban matrix, focusing on breeding birds and their nest predators. I combine observational and experimental approaches to test how anthropogenic subsidies and habitat modification affect avian population demography and predator-prey interactions, and compare these patterns between developed (i.e. residential yards) versus undeveloped (i.e. forested parks) areas within suburban landscapes. During April- August 2011-2014, I examined resource availability, and nest predators, and nest survival of two common birds (American robin, Turdus migratorius and northern cardinal, Cardinalis cardinalis) in seven suburban neighborhoods in the Columbus, Ohio metropolitan area. For the first component of my work, I evaluated demographic differences of robins and cardinals breeding in riparian forest parks and adjacent residential neighborhoods and tested if nest predation was higher in yards. Both robins and cardinals experienced similar nest survival rates in residential yards and forest parks, but there were clear differences in which species were responsible for depredation events. Specifically, domestic cats (Felis catus) were over 5x as frequently documented depredating cardinal nests in yards versus forest parks. For the second component of my work, I tested the hypothesis that wildlife-friendly gardening programs that promote planting trees and shrubs (i.e. increasing woody cover) have the unintended consequence of attracting predators of avian nests by examined relationships between woody cover and diurnal activity patterns of nest predators. Predator activity varied widely among individual yards, but contrary to my hypothesis, the availability of woody cover at either yard or neighborhood scales was not a strong predictor of diurnal activity of five common nest predators. For the third component of my work, I used observational and experimental approaches to investigate how the most common anthropogenic food subsidy, bird feeders, affected predator-prey dynamics in between birds and nest predators in yards. Bird feeders were positively associated with diurnal activity of two nest predators, but the relationship among birdfeeders, nest predators, and nest survival was complex. Nest survival for robins declined with increasing number of bird feeders but only where American crows (Corvus brachyrhynchos) were most frequently detected. For cardinals, nest survival rates showed no association with either feeder availability or predator activity. For the final component of my work, I examined the extent to which nest sites in the residential matrix may offer protection from predation by testing the ability of vegetation characteristics of nest sites and features unique to the urban environment (i.e. roads, buildings, and anthropogenic foods) to predict nest survival. I found that nest site characteristics failed to predict nest survival for cardinals and height was the only significant predictor of robin nest survival. I suggest that the lack of relationship between nest site characteristics and nest fate stem from a diverse predator community that effectively precludes any nest site from being predictably safe for birds breeding in the suburban matrix.

Committee:

Stephen Matthews (Advisor); Amanda Rodewald (Advisor); Stanley Gehrt (Committee Member); Jeremy Bruskotter (Committee Member)

Subjects:

Ecology; Environmental Science; Wildlife Conservation; Wildlife Management

Keywords:

urban ecology; nesting success; predator-prey dynamics; species interactions; anthropogenic resources; subsidies; suburban; nest predators

Silliman, Benjamin AftonProduction of road born sediment of an agricultural road network in southeast Ohio
Master of Science, The Ohio State University, 2015, Environment and Natural Resources
Unbound gravel roads are thought to be one of the largest anthropogenic sources of fine sediments in the stream channels of small watersheds. Sedimentation can reduce water quality in streams; negatively impacting aquatic habitat as well as being a detriment to municipal drinking water sources. With the expansion of natural gas exploration and subsequent increase of the construction and use of rural roads along with the continued use of these roads for timber extraction and recreation, the relationship between rural gravel roads and surface water quality needs to be addressed. This study sought to quantify the mass of sediment a rural road can produce and identify the forces that drive the erosional losses by measuring the production of sediment from the road surface using controlled precipitation experiments. Rain events were simulated on eight road segments at an agricultural research station in eastern Ohio. The road surface produced an average of 42 g of sediment per m2 of road surface with a 30-minute, 1.6 cm precipitation event. Sediment production was shown to be driven by sediment availability but not related to road slope, strength, or drainage characteristics. The production of sediment from the road surface increased with wet traffic use. This study highlights the need to disconnect rural road networks from stream channels in order to prevent negative water quality impacts associated with sedimentation.

Committee:

Roger Williams (Advisor); Elizabeth Myers Toman (Advisor); Kristin Jaeger (Committee Member); Jonathan Witter (Committee Member)

Subjects:

Environmental Science

Bien, Stephanie M.Using Coverboards to Assess Ambystomatid Salamander Populations in Mitigation Wetlands at the Fernald Preserve
Master of Environmental Science, Miami University, 2015, Environmental Sciences
Over 80 acres of wetlands have been constructed at the Fernald Preserve in Hamilton, Ohio to mitigate the loss of wetlands during restoration activities. Two sites with distinctively different mitigation wetlands were chosen to evaluate Ambystomatid salamander populations using two types of coverboards (aluminum and native wood). A total of 33 coverboard plots using a single metal board and four wood boards were placed parallel to one another along the wetland edge and extended into the upland habitat in a distinct uniform grid pattern at the two wetlands. Observations were conducted weekly during salamander breeding seasons over a two year period. A total of four Ambystoma species were observed during the study. We found Ambystomatids using coverboards at each site. Ambystomatids observed occupied the wood coverboard’s more often than metal and were found inhabiting the boards closest to the wetlands 80% of the time. Differences between coverboard types were significant and Ambystomatid presence confirms that pond-breeding salamanders are in fact using restored wetlands at the Fernald Preserve. While coverboards are used by pond-breeding salamanders, they alone did not provide sufficient data needed to assess population size or determine if mitigation for wildlife habitat was successful. The application of multiple sampling techniques to monitor pond-breeding salamanders should be used to fully assess population abundance.

Committee:

Thomas Crist (Advisor); Michelle Boone (Committee Member); Michael Vanni (Committee Member)

Subjects:

Ecology; Environmental Science

Keywords:

coverboards; Ambystomatid salamanders; mitigation wetlands; Fernald Preserve

Mezentseva, KarynaHydrology Of The Tamarack Bog, Bath Nature Preserve, Bath Township, Ohio
Master of Science, University of Akron, 2015, Geology-Environmental Geology
In Ohio, almost 90% of all wetlands have been converted to agricultural land during the last 200 years. Steps are being taken now to restore these important ecosystems. The current study examined the hydrology and geochemistry of a small wetland in order to guide restoration. The wetland is located in the Bath Nature Preserve, Bath, Ohio. The original size was 13.8 acres. However, in the last 50 years it declined to 4.36 acres due to construction of 2 ditches through the south and east sections. Various field work was done in order to characterize the geology, hydrology and hydrochemistry. Sixteen borings were made and ten wells were installed in order to determine site stratigraphy and provide points for chemical water sampling as well as water level monitoring. Three cross-sections of the Bog area were constructed based on sediment core descriptions. Water sampling was conducted in June and November 2014 to provide the data about quality and composition of the Bog water. Bi-weekly water levels measurements were set up to trace the seasonal fluctuations in both perimeter and Bog wells. Visual observations helped to establish the main water source for the Bog (tributary 4) as well as identify other 4 surface water tributaries. The geology is the Bog area is mostly damp clay. Water permeable sand and sandy clay layers are found at the western and south-western part of the Bog Groundwater level monitoring via installed wells revealed that the average hydraulic heads in wells 1A (999.89 ft) and 6 (1001.96 ft) were above the Bog water level (995.1 ft). Water levels in well 2A were above the Bog level only during spring, with the average water elevation 995.73 ft. Water level measurements show a gentle gradient towards the Bog, but observations of surface flow suggest that the bulk of inflow is from tributary 4 (which itself is spring-fed). Calculated vertical hydraulic gradients for pair wells 5B/5C (-0.148), 7/7A (-0.006) and 8/8A (-0.021) suggest downward water movement within the Bog. Water chemistry results of the wetland showed circumneutral pH and elevated concentrations of major ions such as Ca, SO4, and alkalinity. Based on the collected and analyzed data this wetland seems to fit the definition of a fen, and restoration should be so designed.

Committee:

Ira Sasowsky , Dr. (Advisor); David Steer, Dr. (Committee Member); John Senko, Dr. (Committee Member)

Subjects:

Environmental Geology; Environmental Science; Hydrology

Keywords:

Wetland; hydrology; restoration; fen chemistry; the Tamarack Bog

Wei-Haas, Maya LiThe Influence of Dissolved Organic Matter on the Fate of Polybrominated Diphenyl Ethers (PBDEs) in the Environment
Doctor of Philosophy, The Ohio State University, 2015, Geological Sciences
Polybrominated diphenyl ethers (PBDEs) are a class of brominated flame retardant that is ubiquitous in the environment and detected in a variety of both biotic and abiotic samples. Mounting concern over the last several decades over the toxic effects of PBDEs has resulted in a global cessation in their production. Nonetheless, PBDEs will continue to be detected in the environment due to their emission from ongoing use and recycling of PBDE-containing products. PBDEs are distally transported to the Arctic, but little is known about the fate of these compounds in Arctic surface waters, especially in the presence of dissolved organic matter (DOM). The present study is focused on quantifying the influence of DOM in the binding (i.e. dissolved organic carbon—water partition coefficients, KDOC) and abiotic photodegradation rates, mechanisms, and product formation of PBDEs under environmentally relevant conditions. My results indicate that PBDEs strongly bind to DOM, whereby the measured KDOC were nearly an order of magnitude lower than previously reported values for the same PBDE congeners in soil or commercially available organic matter. The KDOC values measured in the present study range from 103.97 to 105.16 L Kg-1 of organic carbon, which increase with congener hydrophobicity. This association with DOM facilitates PBDE photodegradation, resulting in at least a factor of 2 increase in rate constants for the indirect relative to direct photolysis of BDE-47. Photodegradation rates are strongly positively associated with DOM aromaticity and negatively correlated to dissolved oxygen. As such, photodegradation likely occurs via reduction reactions with excited triplet DOM and is expected to be insensitive to reactive oxygen species. Finally, the efficacy of fluence-based rate constants is explored for the direct comparison of experiments conducted under variable natural and artificial sunlight. Using the irradiance normalization method, discussed in this dissertation, with irradiance measurements collected at a site near the Toolik Field Station (Alaska), the potential photolysis rates of BDE-47 in Arctic Alaska were quantified. Overall the results of this study may contribute to our understanding of PBDE fate in aquatic environments and provides partition coefficients and rate constants that may be used in future modeling efforts to predict the fate of PBDEs and structurally similar homologs in the natural environment.

Committee:

Yu-Ping Chin (Advisor); Kristopher McNeill (Committee Member); William B. Lyons (Committee Member); John Lenhart (Committee Member)

Subjects:

Environmental Science

Keywords:

polybrominated diphenyl ether, PBDE, BDE-47, BDE-99, BDE-153, dissolved organic matter, DOM, natural organic matter, NOM, photolysis, photodegradation, fluence-based rate constant, solubility enhancement, partition coefficients, actinometry, fluence rate

Szarek, Harmony KristinSubjectivity in Expert Decision Making: Risk Assessment, Acceptability, and Cognitive Heuristics Affecting Endangered Species Act Listing Judgments for the Greater Yellowstone Ecosystem Grizzly Bear
Master of Science, The Ohio State University, 2015, Environment and Natural Resources
The Endangered Species Act (ESA) was signed into U.S. law in 1973, with the purpose of conserving species at risk of extinction. The law mandates that "the best scientific and commercial data available" be used to determine the protection status of potentially imperiled organisms and provides a process in which decision makers answer two questions: What is the risk to the species? And, is that risk acceptable? The first question can be answered by science, but the second cannot; ultimately, acceptability of a certain level of risk is an ethical or policy decision rather than a scientific decision. Scientific factors and objectivity are scrutinized in this type of expert decision making process, however the other factors such as individual level heuristics that may influence the decision making process have received limited attention to date. This research investigates the process of expert decision making involved in listing determinations for the grizzly bear (Ursus arctos horribilis) in the Greater Yellowstone Ecosystem (GYE) during the timeframe where proposals to delist this population segment of grizzlies from the ESA are being considered. A web-based survey of researchers who have published peer-reviewed findings on Ursus arctos within the past 10 years, and Interagency Grizzly Bear Committee members was conducted to investigate the degree of consensus regarding the threats facing the GYE grizzly and also to understand what factors influence expert listing recommendations. Level of expertise, threat assessment, and six individual heuristics were analyzed in a bivariate logistic regression to determine which factors have an impact on the choice between keeping the GYE grizzly listed or delisted. Findings showed little agreement regarding the threats facing the long-term survival of the GYE grizzly bear population but a clear majority believe grizzlies should remain listed as either endangered or threatened. Of the six heuristics, degree of expertise, and threat assessment factors that were considered in the model, only values (a mutualism wildlife value orientation) and normative beliefs about what other professionals believe were found to be significant influences on expert listing determination.

Committee:

Jeremy Bruskotter (Advisor); Eric Toman (Advisor)

Subjects:

Environmental Science

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