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

Miscanthus x giganteus (miscanthus) is considered an ideal biomass energy crop because of its carbon (C) sequestration potential, water use efficiency, and low fertilizer requirements. Few US studies have measured long-term C sequestration of miscanthus on marginal lands on a decadal scale, and none have been conducted in southeast Ohio. The objective of this study was to measure the potential for C sequestration on abandoned agricultural land, the change in plant and soil nitrogen (N) over a decade, and the photosynthetic capacity in the tenth year of growth. The results revealed that after a decade, C was accumulated in the soil and the sequestration rates were estimated to be 0.20 Mg C ha-1y-1 and 0.54 Mg C ha-1y-1. However, the amount of C accumulated in the miscanthus plots were not statistically different from the adjacent unmanaged plots. There was also no statistically significant change in the amount of N in the baseline soils and after tillage and plowing when compared to the tenth year of growth. There was no statistically significant change in the amount of N found in plants over seven years, but variability in plant N was greater in some years relative to others. Even though the crop of miscanthus was grown without N fertilizers in this study, soil N at 0-30 cm depth was not depleted. There was no difference in plant C between sites, but the C concentration in stem tissue was statistically different over seven years. The photosynthetic capacity of miscanthus measured in this study indicated that the plants were thriving, and C assimilation for growth was consistent with the findings of prior work that evaluated the maximum photosynthetic rates of this species. The combination of soil C sequestration and sustained soil N over a ten-year period has important implications for the sustainability of biomass crops. Ultimately, this study addresses the net environmental benefit of using a perennial grass as a dedicated biomass crop on abandoned agricultural l (open full item for complete abstract)

Committee: Sarah Davis PhD (Committee Chair); Rebecca Snell PhD (Committee Member); Jared DeForest PhD (Committee Member) Subjects: Agriculture; Alternative Energy; Biogeochemistry; Climate Change; Ecology; Environmental Studies; Plant Biology; Soil Sciences; Sustainability

Doctor of Philosophy, The Ohio State University, 2017, Environmental Science

Carbon dioxide concentration is increasing in the atmosphere. This has encouraged the world community to change its energy usages from a fossil resource-based that currently dominates to a renewable bio-based in the future. This opened the door for “solutions from the land” which has led to exploration of land used in the Conservation Reserve Program (CRP) with mixed prairie plant genomes. CRP, a massive public-private partnership program was instituted in 1985 and has reached a total enrolment of about ~10 million hectares that has not been harvested during the past 30 years. Much of the CRP land has degraded, resulting in reduced land cover and a net loss of primary productivity. This research is based on the premise that CRP lands can be harvested for to supply biofuel feedstocks or forage for livestock without long term harmful effects on the plant community and soil environment and without compromising wildlife habitats. This may lead to a Win-Win situation where lignocellulosic materials can be harvested from the CRP lands while at the same time protecting wildlife habitat. In 2009, CRP land located near Piketon, OH was selected for this study. The site was planted in 1999 with nine different warm-season perennials in a prairie mix that had not been harvested for ten years. The site was burned once in 2009 to get rid of weeds and brambles. Treatments imposed on this land in 2009 were designed to test the effect of N fertilization and harvest timing and frequency on the response of CRP land. Five levels of N (0, 10, 20, 40 and 80 kg N ha-1) and three management strategies (A: Harvest in March or April; B: 1st harvest in May, and 2nd harvest in March or April; and C: Multiple harvests during May through October) with four replications in a factorial randomized complete block design with a strip-block restriction on treatment randomization. Energy yields (GJ ha-1 yr-1) increased from 96.0 in 2009 to 287.0 in 2014 with Management-A, 83.0 in 2009 to 202 in 2014 (open full item for complete abstract)

Committee: R. Mark Sulc Ph.D. (Advisor); Warren Dick Ph.D. (Committee Co-Chair); Richard Moore Ph.D. (Committee Member); Norman Fausey Ph.D. (Committee Member) Subjects: Environmental Science; Natural Resource Management; Soil Sciences

Master of Science (MS), Ohio University, 2016, Mechanical Engineering (Engineering and Technology)

The aim of this work was to investigate the use of a catalytic material to accelerate the formation of carbonic acid in a thin liquid film using a vertical membrane mass transfer system. Results comparing the rate of formation of Total Inorganic Carbon (TIC) for similar experimental conditions between the non-catalytic and the catalytic mass transfer systems indicated a statistically significant increase in carbonic acid formation with catalytic mass transfer system. The increased rate of TIC accumulation in the media indicated that the catalytic galvanized mesh potentially accelerated the rate limiting step, i.e. the formation of carbonic acid on the thin liquid film.

Committee: David Bayless Ph.D., P.E., Fellow of ASME and NAI (Advisor); Gregory Kremer Ph.D. (Committee Member); Frank Kraft Ph.D. (Committee Member); Morgan Vis-Chiasson Ph.D. (Committee Member) Subjects: Chemical Engineering; Chemistry; Energy; Engineering; Environmental Engineering; Mechanical Engineering

Doctor of Philosophy, University of Toledo, 2014, College of Natural Sciences and Mathematics

Severe weather and climate anomalies have been observed increasingly in recent decades in United States. Large uncertainties still exist about to what extent ecosystems may respond to such drastic variability of external environmental forcing in terms of their carbon sequestration rates. Challenges also remain in predicting and assessing the potential impact of climate variability and anomaly under anticipated climate change. This study targeted the three most prevalent ecosystems (i.e., a deciduous woodland, a conventional cropland, and a coastal freshwater marsh) in northwestern Ohio, USA. Using the eddy covariance method and supplementary measurements, I examined the effects of recent climatic variability and anomalies (2011-2013) on ecosystem carbon fluxes (i.e., net ecosystem CO2/CH4 exchanges (FCO2/FCH4) and lateral hydrologic fluxes of dissolved organic carbon (FDOC), particulate organic carbon (FPOC), and dissolve inorganic carbon (FDIC)). Gross ecosystem production (GEP) and ecosystem respiration (ER) were the two largest fluxes in the annual carbon budget at all three ecosystems. Yet, these two fluxes compensated each other to a large extent and their balance – FCO2 – depended largely on the interannual variability of these two large fluxes. Around 57-58%, 91-96%, and 77-78% of the interannual FCO2 variability was attributed to functional changes of ecosystems among years, suggesting that the changes of ecosystem structural, physiological, or phenological characteristics played an important role in regulating interannual variability of GEP, ER and FCO2. Freshwater marshes deserve more research attention for their high FCH4 (~50.8±1.0 g C m-2 yr-1) and lateral hydrologic carbon inflows/outflows. Lateral hydrologic flows were an important vector in re-locating carbon among ecosystems in the region. Considerable hydrologic carbon flowed both into and out of the research marsh (108.3±5.4 and 86.2±10.5 g C m-2 yr-1, respectively). Despite marshes accounting for (open full item for complete abstract)

Committee: Jiquan Chen (Advisor); Johan Gottgens (Advisor); Richard Becker (Committee Member); Ankur Desai (Committee Member); Ge Sun (Committee Member) Subjects: Ecology; Environmental Science

Doctor of Philosophy, The Ohio State University, 2014, Environmental Science

Emission and uptake of greenhouse gases and the production and transport of dissolved organic matter in different wetland plant communities are key wetland functions determining two important ecosystem services, climate regulation and nutrient cycling. The objective of this dissertation was to study the variation of methane emissions, carbon sequestration and exports of dissolved organic carbon (DOC) in wetland plant communities of a subtropical climate in south Florida. The plant communities selected for the study of methane emissions and carbon sequestration were located in a natural wetland landscape and corresponded to a gradient of inundation duration. Going from the wettest to the driest conditions, the communities were designated as: deep slough, bald cypress, wet prairie, pond cypress and hydric pine flatwood. Methane fluxes from the different communities did not show a discernible daily pattern, in contrast to a marked increase in seasonal emissions during inundation. Median and mean + standard error fluxes in g CH4-C.m-2.d-1 were higher in the deep slough (11 and 56.2 + 22.1), followed by the wet prairie (9.01 and 53.3 + 26.6), bald cypress (3.31 and 5.54 + 2.51) and pond cypress (1.49, 4.55 + 3.35) communities. The pine flatwood community acted as a net sink (0.0 and -1.22 + 0.81). Seasonality in methane emissions was positively correlated with the water levels, but not with soil temperature. However, longer inundation periods did not necessarily result in higher methane emissions. The mean carbon concentration from the surface to the depth of maximum 137Cs activity between communities was similar in the deep slough, bald and pond cypress (446, 405 and 369 g-C Kg -1, respectively). However, carbon sequestration rates (g-C.m-2.yr-1) were highest in the deep slough (104 + 14), followed by the pond cypress (60 + 9), bald cypress (30 + 2), wet prairie (24 + 1) and pine flatwood (15 + 1) communities, without an apparent relationship with the duration of the in (open full item for complete abstract)

Committee: William J. Mitsch Ph.D (Advisor); Gil Bohrer Ph.D (Advisor); James Bauer Ph.D (Committee Member); Jay Martin Ph.D (Committee Member) Subjects: Biogeochemistry; Climate Change; Ecology; Environmental Engineering; Environmental Management; Environmental Science; Environmental Studies; Hydrology; Natural Resource Management; Water Resource Management

Doctor of Philosophy, The Ohio State University, 2014, Environmental Science

For more than three decades the practice of creating and restoring wetlands has focused on offsetting lost habitat and ecosystem function, and on water quality improvement. For the past decade wetland research has shifted to the role of wetlands in climate change with most studies dealing with one component of the carbon cycle. This dissertation developed a detailed carbon budget of the two flow-through experimental wetlands at The Ohio State University's Olentangy River Wetland Research Park (ORWRP) in Columbus, Ohio, USA. The two 1-ha flow-through riverine wetlands were created in 1994 (one planted and the other naturally colonized) adjacent to a third-order stream in central Ohio. The dissertation also investigated previous methods used for estimating methane emissions at the experimental wetlands to better permit comparison of data for almost a decade, and estimated the influence the autochthonous productivity had on carbon exported from these two wetlands. Detailed carbon budgets from 2008 to 2010 were created for the two wetlands. Measurements were taken of dissolved non-purgeable organic carbon (NPOC), dissolved inorganic carbon (DIC), fine particulate organic carbon (FPOM), and coarse particulate organic carbon (CPOM). Methane emissions, soil sequestration, aquatic primary productivity, and macrophyte above-ground net primary productivity were also included in the carbon budget based on other studies. The carbon budget successfully balanced inputs (1,838 ± 41 g C m-2 year-1) and export/sequestration (1,846 ± 59 g C m-2 year-1) with only a 0.5 % over estimation of export in relation to input and 12.8 % of the input carbon from both hydrologic and biologic inputs accumulating into the wetland soil. FPOM and CPOM concentrations and exports were positively correlated with hydrologic flow under most circumstances; NPOC and DIC concentrations were usually negatively or poorly correlated with hydrologic flow. In all seasons, except winter, the change of total carbo (open full item for complete abstract)

Committee: William Mitsch PhD (Advisor); Richard Moore PhD (Committee Chair); Richard Dick PhD (Committee Member); Bryan Mark PhD (Committee Member) Subjects: Biogeochemistry; Climate Change; Ecology; Environmental Science

MS, University of Cincinnati, 0, Engineering and Applied Science: Environmental Science

An innovative method of recovering carbon dioxide from flue gas has been studied whereby reclaimed magnesium hydroxide is used as the scrubbing agent. A slurry of magnesium hydroxide (Mg(OH)2) was used to separate carbon dioxide (CO2) from flue gas in an absorber. Thermodynamic equilibrium calculations indicate that by scrubbing flue gas already cleaned of its sulfur dioxide (SO2) concentration, 99% of the CO2will react to form more soluble magnesite (MgCO3) and hydromagnesite ((Mg4(CO3)3(OH)2) in the scrubber, and that CO2 will be released when the resulting solution is heated. Turbine waste heat can be used to heat the CO2-laden slurry, creating a rich stream of CO2 gas for further processing. The Mg(OH)2 slurry can then be recycled for further CO2 absorption.

This project established proof of concept of this model by studying the reaction characteristics of the absorption of CO2 by solutions containing Mg(OH)2 in a bench-scale bubble column operated under realistic conditions. An NDIR analyzer measured the CO2 concentration in the exit gas. From this data, the steady state reaction characteristics have been determined using a simulated flue gas of 5%, 10%, and 20% CO2, Mg(OH)2 slurry concentrations of 0.027, 0.068, and 0.14 moles per liter at temperatures of 25, 45, and 65oC. Both commercially available Mg(OH)2 and reclaimed Mg(OH)2 were used. Finally, the mass transfer coefficient K'AG was calculated for the system.

Committee: Timothy Keener Ph.D. (Committee Chair); Sumana Udom Keener Ph.D. (Committee Member); Soon Jai Khang Ph.D. (Committee Member) Subjects: Environmental Science

Master of Science in Environmental Science, Youngstown State University, 2008, Department of Geological and Environmental Sciences

Adsorption is considered one of the more promising technologies for capturing CO2 from flue gases. This research shows an efficient chemical adsorption method capable of capturing carbon dioxide under moist conditions from flue gases of coal-fired power plants. Carbon dioxide was chemically adsorbed by the reaction K2CO3*1.5H2O + CO2 ↔ 2KHCO3 + 0.5H2O + heat. Moisture however, plays a significant role in the chemical adsorption process, which readily facilitates the adsorption process. Moisture usually contained as high as 8-17% in flue gases, badly affects the capacity of conventional adsorbents such as zeolites, but the present technology has no concern with moisture; water is rather necessary in principle as shown in the equation above. Carbon dioxide uptake occurred at a temperature of 60°C and the entrapped carbon dioxide was released by the decomposition of potassium bicarbonate to shift the reaction in the reverse direction. The decomposition occurred at high enough temperatures of 150°C to ensure complete regeneration of the sorbent. For the purpose of this research, emphasis was placed more on the adsorption process. When compared to other processes such as the conventional amine process, it provided an efficient, low utility cost and energy-conservative effect. The activated carbon was prepared by 20% by weight of K2CO3 and samples used during the experimental runs were dried at 60°C for the 26-hour runs and at 25°C and 125°C for the air-dried and oven-dried samples respectively for the 48-hour runs. The samples all got to the saturation point after 6 hours of exposure to carbon dioxide and gave adsorption capacities in the range of 2.5 to 3.5mol CO2/mol K2CO3 for all experimental runs performed in this research.

Committee: Douglas Price PhD (Committee Chair); Felicia Armstrong PhD (Committee Member); Jeffrey Dick PhD (Committee Member); Alan Jacobs PhD (Committee Member) Subjects: Chemical Engineering; Chemistry; Energy; Engineering; Environmental Engineering; Environmental Science

Master of Science, The Ohio State University, 2011, Geological Sciences

Subtle shifts in the lithology or diagenetic history of a sedimentary formation may result in different reservoir properties of that formation, by affecting porosity and permeability in varied ways. This may create a geographic heterogeneity that will alter the accuracy of reservoir storage estimations of a formation. The Mt. Simon and Rose Run Sandstones of Ohio are both established as appropriate targets for the sequestration of supercritical CO2, but each of these formations may contain heterogeneities that are heretofore unaccounted for by standard well exploration. The porosity and permeability of these formations may differ based upon their local diagenetic histories. To account for these differences, the concentrations of quartz and feldspar within these sandstones offer evidence of diagenetic processes that have occurred in the past and those that may still occur in the future. Grain-size variations and any geographic trends they show can also be used as evidence of diagenetic variations that may indicate further heterogeneities that will affect the porosity and permeability of the formation on a local level. In this study, feldspar concentrations in both the Rose Run and Mt. Simon Sandstones are studied, on a microscopic level, and are shown to be extremely low with subtle variation of concentration based on location. Grain sizes of these formations also show subtle variations based on geographic location. Both results show that further study into the locally geographic differences of these formations will be necessary in order to accurately evaluate their storage capacity.

Committee: Michael Barton Dr. (Advisor); Loren Babcock Dr. (Committee Member); David Cole Dr. (Committee Member) Subjects: Earth; Energy; Environmental Engineering; Environmental Geology; Environmental Science; Environmental Studies; Geological; Geology; Geotechnology

Doctor of Philosophy, The Ohio State University, 2011, Environmental Science

In an attempt to slow the increase in atmospheric CO2 enrichment, researchers are looking at the capacity of world soils to sequester carbon (C) and mitigate global climate change (GCC). Analyses of U.S. turfgrass soils throughout diverse ecoregions indicated that home lawns sequester soil organic carbon (SOC). Rates of SOC sequestration to 15 cm depth ranged from 0.01% yr-1 to 0.70% yr-1 with the majority of lawns sequestering SOC to concentrations of 2-3%. Notably high SOC concentrations were observed in Minneapolis, MN (5.6%), Wooster, OH (3.4%), Denver, CO (3.2%), and Duluth, MN (3.1). In contrast, notably low concentrations were observed for soils located in Atlanta, GA (1.5%). Differences in SOC concentration and pool were attributed to differences in climatic and soil properties across ecoregions. The mean annual temperature (MAT) was negatively correlated with SOC concentration and pool, while both mean annual precipitation (MAP) and soil bulk density (ρb) indicated a nonlinear interaction with optimal SOC concentrations at MAP of 60-70 cm yr-1 and ρb of 1.4-1.5 Mg m-3. Additionally, soil nitrogen (N) concentration was positively correlated with both SOC concentration and pool. Rates of SOC sequestration ranged from 0.9 Mg C ha-1 yr-1 to 5.4 Mg C ha-1 yr-1, with a national average of 2.8 ± 0.3 Mg C ha-1 yr-1. Differences in rates of SOC sequestration were also attributed to differences in MAP, soil N concentrations, and ρb, however, SOC sequestration rate was also positively correlated with fine soil texture content and pH. The potential C sink capacity of soils was determined and ranged from 20.8 ± 1.0 Mg C ha-1 in Portland, ME to 96.3 ± 6.0 Mg C ha-1 in Minneapolis, MN, with an average across ecoregions of 45.8 ± 3.5 Mg C ha-1. The hidden carbon costs (HCC) of home lawn maintenance due to fertilizer use (0.06 Mg Ce ha-1 yr-1) and mowing fuel combustion (0.19 Mg Ce ha-1 yr-1) produced a mean total emission across sites of 0.25 Mg Ce ha-1 yr-1. Accounting fo (open full item for complete abstract)

Committee: Rattan Lal (Advisor); Elena Irwin (Committee Member); Karl Danneberger (Committee Member); Richard Moore (Committee Member) Subjects: Agriculture; Atmospheric Sciences; Biology; Botany; Climate Change; Ecology; Environmental Education; Environmental Management; Environmental Science; Environmental Studies; Gases; Land Use Planning; Landscaping; Plant Biology; Plant Sciences; Sociology; Soil Sciences; Ur

Master of Science, The Ohio State University, 2010, Soil Science

Since the industrial revolution, atmospheric concentrations of CO2 (carbon dioxide) have been increasing. To mitigate or slow the accession of CO2, research in the areas of terrestrial and soil C (carbon) sequestration is on the rise. This study focuses on the potential of residential landscapes to sequester C. Urbanized land covers approximately 40.6 Mha (million hectares) in the U.S with approximately 41% of the U.S. urban areas are used for residential neighborhoods. As urbanization increases, the percentage of land converted into residential homes and landscapes is also increasing. Turfgrasses are common in urban areas and cover 16 – 20 Mha in the U.S. which includes residential, commercial, and institutional lawns, parks, golf courses, and athletic fields. Home lawns constitute approximately 6.4 Mha of this turfgrass area. In this study tree, shrub, and lawn C sequestration rates are estimated based on 80 million U.S. single family residential homes with a residential lot size of 2,000 m2. A typical US home is 93 m2 with a 2-car garage or carport size of 38 m2 and a deck or patio of 38 m2. The house is assumed to be sited in the middle of the lot, with a driveway size of 168 m2 and a sidewalk size of 122 m2. The remaining area of 1,541 m2 is landscape. The first model estimates the influence of home lawns on net soil organic carbon (SOC) sequestration taking into account the hidden carbon costs (HCC) of fertilizer, mowing, irrigation, and pesticide applications. SOC sequestration and HCC data rates are established from literature. The net SOC sequestration rate is assessed by subtracting the HCC from gross SOC sequestered. Lawn maintenance practices range from low to high management. Low management or minimal input (MI) includes mowing only, with a net SOC sequestration rate of 63.5 – 69.7 kg C lawn-1 yr-1. Do-It-Yourself (DIY) management by homeowners is 107.7 – 124.8 kg C lawn-1 yr-1. High management is based on university and industry-standard best managem (open full item for complete abstract)

Committee: Rattan Lal (Advisor); Nicholas Basta (Committee Chair); Karl Danneberger (Committee Chair); Michael Boehm (Committee Chair) Subjects: Agriculture; Soil Sciences

Master of Science, The Ohio State University, 2009, Natural Resources

This study was composed of two research components that examined the effects of tallgrass prairie land use changes on soil organic C (SOC). The central objective of the first study was to examine changes in SOC and a suite of soil quality parameters in former agricultural soils now under restored tallgrass prairie. This research was conducted at the Prairie Nature Center, on the OSU Marion campus in northwest Ohio. Soils from 31 year, 13 year, and 8 year- old prairies, and adjacent agricultural and lawn soils were analyzed. These soils demonstrated significant increases in SOC concentration, particulate organic matter (POM), water stable aggregation (%WSA), aggregate mean weight diameter (MWD), total porosity (ft), and available water capacity (AWC), and significant decreases in soil bulk density (ρb) associated with time under tallgrass prairie. The second research component observed long and short-term effects of the conversion of remnant tallgrass prairies to wheat production, in north central Kansas. Total C, microbial biomass C (MBC), and a particle size fractionation of SOC were used as indices of change. Long-term sites showed changes in all fractions analyzed, while only MBC showed significant change in the short-term study. This study provides further evidence that perennial plant communities store and cycle C, and maintain ecosystem processes at far greater levels than annual plant communities.

Committee: Rattan Lal PhD (Advisor); Martin Shipitalo PhD (Committee Member); Frank Calhoun PhD (Committee Member) Subjects: Soil Sciences

Doctor of Philosophy, The Ohio State University, 2007, Environmental Science

Rapid urbanization is increasing turfgrass covered soils throughout the United States. Research on carbon (C) dynamics in turfgrass systems can enable their exploitation as sinks of atmospheric C. In the first study long term (15years) effect of management programs that differed in the application of nitrogen (N) fertilizer, and pesticides on soil organic C (SOC) and turf quality in Kentucky bluegrass lawns was evaluated. The SOC pools in turfgrass systems can be influenced by the amount of N applied and weeds with their N fixing ability and broad leaf cover can reduce turfgrass aesthetic quality but play an important role in the biomass returned to the soil and therefore contribute to C sequestration. In the second study C cost occurring from the use of fossil fuels required for the production, transport, storage, and application of fertilizers, pesticides, and mowing was calculated and compared to the gain of SOC using a sustainability index. Greater sustainability of turfgrass systems for C can be achieved by reducing or replacing the use of mineral with organic fertilizers, replacing chemical with biological pesticides, mowing less often, and returning clippings. In the third study soil carbon dynamics and litter decomposition as affected by grass species perennial ryegrass (PR) and tall fescue (TF) with low and high endophyte infection were evaluated. The SOC along with its labile fractions microbial biomass C (MBC) and dissolved organic C (DOC), soil surface CO2 flux, and litter bag decomposition in the field were analyzed and found to be not different between treatments. The last study determined the spatial variability in SOC pools in urban landscapes. The SOC was more variable across a residential neighborhood block in the City of Wooster than across the lawns in the study region of Wayne and Holmes County, OH. Considering the average SOC pool of 25 Mg ha-1in the 0-12 cm depth and the total turf area for Ohio lawns at 6733 km2, we calculated the total Ohio (open full item for complete abstract)

Committee: Parwinder Grewal (Advisor) Subjects:

Master of Arts, Miami University, 2006, Geography

This study investigated the variability of soil organic carbon within the Old Woman Creek watershed and the influence of landuse, soil texture, geomorphic surface and depth on SOC variability. Soil samples were collected at 0-30cm and 30-60cm depths in forest, pasture, conservation tillage and conventional tillage sites in both the Lake Plain and Till Plain. The Lake Plain had higher SOC than the Till Plain, and geomorphic surface had a greater affect at the 30-60cm depth than the 0-30cm depth. SOC was higher at the 0-30cm depth than the 30-60cm depth. Forest and pasture landuses had higher SOC than conservation and conventional tillage landuses. Conventional tillage had higher SOC than conservation tillage. Linear regression models and soil survey data were used to extrapolate SOC data to the watershed. Linear regression models could be useful estimators of SOC when used with site-specific data.

Committee: William Renwick (Advisor) Subjects: Agriculture, Soil Science

Doctor of Philosophy, The Ohio State University, 2013, Environmental Science

Here we investigate the application of biochar to a maize (Zea mays)-soybeans (Glycine max L.) rotation in the U.S. Midwest in order to assess the agronomic impacts and changes to soil physical, chemical and biological properties. Biochar is a carbon-rich co-product of thermal degradation of biomass precursor material, a process called “pyrolysis,” intended for the use as a soil amendment as opposed to combusted for heat or energy. Biochar could offer a sustainable means of generating energy, sequestering atmospheric CO2 (thereby mitigating climate change), and increasing agronomic productivity of crops through soil quality enhancement. At a global scale biochar could sequester >1 Pg C yr-1, thereby substantially helping to mitigate climate change. At present, the majority of long-term field trials using biochar as a soil amendement have focused on highly weathered and degraded soils mainly in the tropics and subtropics. Very little long-term field trials have been conducted on agroecosystems in temperate parts of the world. Our research aimed to fill this void, by conducting a 4-year field experiment (2010-2013) with oak-derived biochar from a slow pyrolysis process at ~425°C at three rates (0 t ha-1, 5 t ha-1 and 25 t ha-1) with 100% and 50% of nitrogen fertilizer (146 kg ha-1 N and 72 kg ha-1 N, respectively) on a maize -soybean rotation on an Ohio alfisol soil. Variables analyzed included to total above-ground biomass, grain yield, leaf and grain nutrient uptake; soil nutrient storage, moisture capacity, aggregate stability, and greenhouse gas emissions (CO2, CH4, and N2O). Oak biochar was applied at two rates, 5 and 25 tons per hectare (t ha-1) plus a control with two rates of nitrogen (N) fertilizer—50% recommended N and 100% recommended N for “~150 bushel an acre corn" from the Ohio State University agricultural extension office (LaBarge and Lindsey, 2012). Overall, our study revealed mixed results. Biochar did tend (open full item for complete abstract)

Committee: Rattan Lal (Advisor) Subjects: Environmental Science

Master of Science, The Ohio State University, 2008, Graduate School

Committee: Not Provided (Other) Subjects:

Master of Science, The Ohio State University, 2023, Environment and Natural Resources

Since the beginning of time Earth's carbon cycle has self-regulated, experiencing periods of warming and cooling with changing amounts of carbon in the atmosphere. Today, human activity is rapidly changing the climate through the addition of greenhouse gases to the atmosphere like carbon dioxide (CO2). To prevent disastrous outcomes caused by climate change, it is vital to halt greenhouse gas emissions, however, this is only one part of the solution. To keep global temperatures from increasing more than 2° C, CO2 removal must also be an integral part of the solution. The objectives of this research were to conduct a laboratory experiment and investigate the carbonation of concrete within soil as a viable option to sequester atmospheric carbon, analyze how concrete carbonation changes with fragment size, and understand the environmental impacts of adding concrete to soil. Soil samples from Waterman Agricultural and Natural Resources Center were collected and placed into 30 cm columns with different mixtures of crushed recycled concrete to test concrete in soil as an enhanced weathering material. Four different treatments were tested and were comprised of 1) 100% soil (S samples), 2) 90% soil and 10% concrete by weight of 0.25-0.71 mm diameter fragments (F samples), 3) 90% soil and 10% concrete by weight of 8 mm diameter fragments (L samples), and 4) 100% concrete composed of 8 mm diameter fragments (C samples). Four replications of each treatment were tested for a total of 16 samples. Approximately 40 cm3 of deionized water was added to each sample every day from a drip irrigation system for a total amount of 940-990 mm yr-1 throughout the experiment to simulate the amount of precipitation received by Columbus, OH in one year, with leachate continuously collected underneath the columns. After 16 weeks, the soil and concrete mixtures were removed from the columns and tests were conducted on the soil and leachate samples. The results from this study show that con (open full item for complete abstract)

Committee: Rattan Lal (Advisor); Berry Lyons (Committee Member); M. Scott Demyan (Committee Member); Matt O'Reilly (Committee Member) Subjects: Civil Engineering; Climate Change; Environmental Science; Soil Sciences

Master of Science, The Ohio State University, 2022, Environment and Natural Resources

Soils represent one of the largest terrestrial stocks of carbon (C) and adopting land management techniques that increase soil C has the potential to off-set rising atmospheric CO2. Yet in order to recommend land management techniques that maximize soil C sequestration, researchers must look beyond bulk soil C budgets to investigate where, how, and for how long soil C is stored. Soil organic matter (SOM) fractionation separates bulk SOM into portions of varying stability and permanence associated with different C turnover times – including particulate organic matter (POM) (active), silt and clay (SiC) (intermediate), and resistant soil organic carbon (rSOC) (refractory) – and provides a mechanistic understanding of soil organic C (SOC) decomposition and stabilization. Changes to intermediate and refractory pools can take decades to appear, and very few studies longer than 5 years exist. Here, we seek to determine the effects of disturbance and crop diversity on the accumulation of new, corn-derived C (herein referred to as C4-C vs. “old” C3-C) in three soil fractions over 50 years of cultivation in a long-term experiment with repeated samplings. We employed size, density, and chemical fractionation, natural 13C abundance, and MIRS specific peak area analysis to identify changes in SOM composition, SOC stock (Mg ha-1), and C4-derived C stocks (Mg ha-1) of surface soil samples (0-15 cm) from the Triplett-Van Doren long-term no-tillage experiment in Wooster, OH from 1971, 2003, and 2020. Land use treatments examined were moldboard plow (PL) and no-tillage (NT), combined with continuous corn (Zea mays) (CC) and corn-soy (Glycine max) (CS) crop rotations in a full-factorial randomized complete block design. A mixed modeling approach revealed that NT and CC increased SOC stocks in POM and SiC fractions compared to PL and CS. POM made up 16.7% of total SOC, SiC 56.0%, and rSOC 4.5%. C4-derived C stocks in the SiC fraction increased over time under NT (p < 0.0001) and plate (open full item for complete abstract)

Committee: M. Scott Demyan (Advisor); Steve Culman (Committee Member); Christine Sprunger (Committee Member) Subjects: Soil Sciences

Master of Science in Environmental Science, Cleveland State University, 2020, College of Sciences and Health Professions

Compared to their natural counterparts, trees in urban ecosystems experience distinctive environmental conditions which can be both beneficial and harmful to tree functions and fitness. Thus, the morphological, phenological, and physiological functions of trees in urban ecosystems can be unique and might not be predictable from patterns identified in natural forests where most research on tree ecology has occurred. To better understand how different tree species contribute to ecosystem services in urban environments, we estimated a number of key performance metrics and functional traits for species commonly planted in urban areas. Between April of 2017 and December of 2019, we monitored 42 species of trees across two sites growing in open, urban settings. Radial growth of each individual was measured weekly from April to December using dendrometer bands. Leaf phenology was assessed weekly during leaf development and senescence. Wood phenology was estimated using the RDendrom package in R. Annual C sequestration was estimated using radial growth data, allometric equations (Urban Tree Database), and species-specific wood density and stem C% estimates (TRY database). We also measured several important anatomical, morphological, physiological, and phenological traits. In 2019, we measured a number of canopy characteristics on a smaller subset of individuals (n=137) across 38 species. Lastly, we measured a number of potentially important abiotic covariates, including soil texture, soil pH, canopy light availability, and various topographic variables. We found evidence that performance metrics (basal area growth), canopy characteristics, and functional traits varied significantly among the species in our study. Moreover, the performance metrics and traits which are directly linked to specific ecosystem services, such as aboveground carbon sequestration and drip line leaf area index, also varied significantly among the species in our study. This suggests that particular (open full item for complete abstract)

Committee: Kevin Mueller (Advisor); Emily Rauschert (Committee Member); Thomas Hilde (Committee Member) Subjects: Botany; Ecology; Environmental Science; Statistics; Urban Forestry

Doctor of Philosophy, The Ohio State University, 2019, Agricultural, Environmental and Developmental Economics

This dissertation examines the conservation and economic development effects of community forest management in the Maya Biosphere Reserve (MBR). Maintaining the world's forest resources in developing countries has been a difficult, but necessary task since conserving tropical forests is crucial for preserving biodiversity and sequestering carbon. However, many communities located near the forest depend on extracting forest resources as a source of income and many governments in developing countries cannot devote enough resources to enforce forest protection efforts. This creates an overexploitation problem since many of these forests are common-pool resources that are rivalrous and non-excludable because of the lack of enforcement of the ill-defined property rights. To remedy this issue, some countries have provided communal property rights to encourage sustainable resource use (Ostrom 1990; Schlager and Ostrom, 1992). The idea is that households will work together and monitor each other to protect the area of land to which they have property rights from over exploitation. In exchange, the group that manages the area is given exclusive access to the forest resources and is able to earn a sustainable source of income. However, for community-based forest management to have a higher likelihood of being effective, households that are participating in the forest management system can receive an incentive in addition to the forest being conserved. The goal of this dissertation is to assess whether the economic development and conservation benefits of the community forest concessions in the Maya Biosphere Reserve are effective and whether receiving payments for strict conservation would be preferred by households. Chapter 1 is an introduction into community forestry and the background of the Maya Biosphere Reserve. In Chapter 2, I examine the impact of concession membership on annual household income to determine if the benefits of participating in community (open full item for complete abstract)

Committee: Brent Sohngen (Advisor); Daniela Miteva (Committee Member); Abdoul Sam (Committee Member); Frank Lupi (Committee Member) Subjects: Conservation; Economics; Environmental Economics; Forestry