Doctor of Philosophy, Miami University, 2015, Geography

Agricultural intensification is often posited as a critical strategy to meet growing food demand and reduce world hunger. However, agricultural intensification also comes with downsides. This dissertation seeks to better understand the role of agricultural intensification in meeting the dual food and environmental challenges. Chapter 2 examines the effects of nitrogen (N) fertilization and conservation tillage on measured soil organic carbon (SOC) stocks in the agricultural soils of the United States. N fertilization positively affects estimated SOC, but the magnitude differs due to varying cropping systems: when cropping frequency increases one, measured SOC under fertilized treatment increases by 6.5%. Conversion from conventional tillage to no tillage increases SOC stock. Moreover, the longer the time in no tillage, the greater the amount of SOC compared to conventional tillage. This study confirms that adoption of N fertilization and conservational tillage can potentially increase measured SOC if management practices are designed properly. Chapter 3 explores the relationship between changes in agricultural yield and cropland area. The yield-cultivated area dynamics are evaluated under the context shaped by variables that can potentially affect cropland extent. Cropland area increases at a much lower rate than total agricultural production; however, actual declines in cultivated area only occur between 1980 and 1985. The amount of CRP area has a positive impact on land-sparing, whereas USDA farm subsidies and agricultural commodity prices negatively impact land-sparing. In Chapter 4, I analyze the spatial patterns of agricultural expansion and crop rotation systems in the Midwest Corn Belt during 2006-2013 when there is a doubling of corn and soybean prices. I find that corn and soybean continuously expand whereas most other crops shrink. Grassland is the most affected, with a total net loss of 3.9 million acres. Grassland loss is mainly concentrated along the w (open full item for complete abstract)

Committee: Mary Henry (Committee Chair); Larry Barnthouse (Committee Member); John Maingi (Committee Member); Hank Stevens (Committee Member); Thomas Crist (Committee Member) Subjects: Agricultural Economics; Environmental Science; Geographic Information Science; Geography

Master of Science, The Ohio State University, 1975, Graduate School

Committee: Not Provided (Other) Subjects:

Master of Science in Environmental Science, Youngstown State University, 2021, Department of Physics, Astronomy, Geology and Environmental Sciences

Although frequently overlooked or omitted, ecosystem services provide an environment for the survival of life on earth, including humans. Soil is a critical compartment for ecosystem services composed of solids, gasses, water, and micro and macro flora and fauna. Soil functions include water holding capacity, nutrient holding and cycling, support for microbial life, carbon capture, and other many other unseen benefits. Within society a main use of soil is agriculture for growth of food, fiber, and other necessities for civilization. Agricultural practices can consist of different techniques, two common categories are conventional and conservation methods. Conventional tillage utilizes turning of the soil to prepare the seedbed and remove unwanted plants. In conservation methods the use of no tillage or reduce tillage is used, where the soil is minimally disturbed, and the seeds are inserted into small slits or openings. Aggressive tillage can affect soil ecosystem function and limit the quality of soil health by decreasing porosity, reducing microbial processes, and increasing erosion. Seven farm fields in Trumbull County, OH, were sampled to investigate the connection between agricultural method and soil quality characteristics that contribute to overall soil health and productivity. Composite soil samples consisting of 2.5 cm soil cores separated into top 15 cm layer and bottom layer were evaluated for organic matter, bulk density, soil texture, plant available phosphorus, pH, total nitrogen, salinity, and percent porosity using standard methods. The data composed of 32 samples, with 16 samples from the top layer and 16 from the bottom layer. The fields were ranked one to four, with a ranking of one indicating conventional methods to ranking of four with the highest amount of conservation practices applied. Statistical analyses included descriptive statistics, mean comparison, one-way ANOVA, Principal Component Analysis, and backwards linear regressions using S (open full item for complete abstract)

Committee: Felicia Armstrong PhD (Advisor); Colleen McLean PhD (Committee Member); Albert Sumell PhD (Committee Member); Lee Beers MS (Committee Member) Subjects: Agricultural Economics; Agricultural Education; Agriculture; Agronomy; Earth; Economic Theory; Environmental Economics; Environmental Education; Environmental Health; Environmental Philosophy; Environmental Science; Environmental Studies; Soil Sciences; Sustainability

BS, Kent State University, 2021, College of Arts and Sciences / Department of Biological Sciences

Mine reclamation practices under the Surface Mining Control and Reclamation Act of 1979 often resulted in minimal natural succession due to changes in soil physical characteristics. As part of the reclamation process, industrial rollers were used to compact the soil, and grasses were seeded to stop nutrient runoff and prevent further pollution downstream. Although this brought herbaceous plants back to the sites, the resulting soil conditions made it nearly impossible to grow larger woody plants due to high soil bulk density and an inability to spread roots. To counteract this problem, new methods are designed to reverse reclamation effects on soil bulk density by soil ripping - dragging large shanks sunk one meter into the ground in a 2x2 meter grid pattern, followed by tree-planting at rip intersections. To assess the effectiveness of soil ripping at two former mines managed by Cuyahoga Valley National Park, we measured near-surface and profile soil bulk density in non-ripped areas, within rips, and at cross-rips. Additionally, we measured soil pH, C:N ratio, and plant-available nutrients. The mines we studied showed higher bulk densities of surface soil in the rips than in the non-rips, in contrast to our expectations. However, at depths between 20cm and 60cm, the bulk densities were lower in the rips than in the non-rips. This suggests that, immediately after ripping, soils were lower in bulk density, but erosion washed fine clay particles into the surface of the rips. Soil chemistry differed after ripping, but only for some of the elements we measured. These short-term results are beneficial for determining the next steps of restoration at the reclaimed surface mines. We hope this ripping process will have a lasting positive effect on survival and growth of our trees.

Committee: Christopher Blackwood Ph.D. (Advisor); Anne Jefferson Ph.D. (Committee Member); Lauren Kinsman-Costello Ph.D. (Committee Member); Elda Hegmann Ph.D. (Committee Member) Subjects: Biogeochemistry; Biology; Ecology; Environmental Science; Geology

Doctor of Philosophy, The Ohio State University, 2019, Food, Agricultural and Biological Engineering

Farmers today are faced with two yield robbing factors within their fields: soil compaction and residue cover. Soil compaction reduces yield by restricting water permeability, reducing metabolic function of root cells and restricting root growth. Residue cover reduces yield by decreasing soil temperature, decreasing germination and emergence. Tillage can alleviate these potential problems by incorporating a portion of the residue cover and mitigating soil compaction. With crop residue and soil compaction varying across a field, it may prove beneficial for farmers to continually adjust tillage depths on a spatial basis. The ability, however, to know when and where these depth changes should occur and to implement these changes is not available to producers. This dissertation reports on a series of investigations designed to develop and demonstrate the first approach to spatially variable or “prescription” tillage. The investigations were designed to: 1) develop an agronomic rule set for generation of prescription tillage maps based on historical data (i.e. grain yield, equipment weights and traffic paths, crop residue and remote-sensed imagery); 2) develop a control system and associated algorithms to allow for independent actuation of soil engaging tools of a multi-tool tillage implement (Case IH Ecolo-Tiger 875) thereby enabling “prescription” tillage; 3) model draft and power requirements of independent tool depth settings and implement ground speeds for the created prescription enabled tillage system; and 4) develop and demonstrate an algorithm for ISOBus Class III implement control of tractor settings including gear selection and engine speed via throttle position. The agronomic rule set was capable of predicting the amount of required biomass residue or surface coverage according to soil elevation and soil type and adjusting the disk gang depth with required and available biomass residue. The agronomic was capable of adequately changing shank d (open full item for complete abstract)

Committee: Scott Shearer (Advisor); John Fulton (Committee Member); Elizabeth Hawkins (Committee Member); Erdal Ozkan (Committee Member) Subjects: Agricultural Engineering

MS, Kent State University, 2018, College of Arts and Sciences / Department of Earth Sciences

The Cuyahoga Valley National Park (CUVA) was established in 1974 as a National Recreation Area. At that time, park staff aimed to reclaim 40 degraded sites within CUVA following guidelines outlined in the Surface Mining Control and Reclamation Act of 1977 (SMCRA). This included restoring abandoned slopes to more natural grades and seeding them with a mix of native and non-native grasses, legumes, and woody plants. Plants were chosen to prevent erosion, improve water quality, and be visually appealing. It was projected that most non-native species would give way to native woody species and allow for natural succession to occur within 20 years. While decreased erosion and increased plant life were documented by the 1990s, non-woody and invasive plants continue to dominate. In 2016, the park secured funding for deep-ripping reclamation with the goal of improving conditions for reforestation. The objectives of this thesis were to research the history of mine reclamation in this area and determine the effects of both SMCRA reclamation and deep-ripping reclamation on soil texture, soil bulk density, and saturated hydraulic conductivity on previously glaciated non-coal surface mines. Five abandoned mine sites and four forested reference areas of similar location, slope, and aspect were chosen for this study. At these sites, I have collected 205 bulk density soil samples and 289 soil probe samples for grain size distribution analysis and have performed 66 infiltration rate measurements to determine saturated hydraulic conductivity. Soil texture encompasses silt loams, loams, and sandy loams. Bulk density of the top 5 cm of soil is significantly higher in the mined sites in comparison to forest locations, though values are not high enough at the mine sites to restrict root penetration. However, bulk density samples at depth exceed root restriction values. Mine sites also have significantly slower values for saturated hydraulic conductivity than reference locations. Deep-r (open full item for complete abstract)

Committee: Anne Jefferson (Advisor) Subjects: Geology; Geomorphology; Soil Sciences

Doctor of Philosophy, The Ohio State University, 1983, Graduate School

Committee: Not Provided (Other) Subjects: Agriculture

Doctor of Philosophy, The Ohio State University, 1982, Graduate School

Committee: Not Provided (Other) Subjects: Agriculture

Doctor of Philosophy, The Ohio State University, 1975, Graduate School

Committee: Not Provided (Other) Subjects: Education

Doctor of Philosophy, The Ohio State University, 1968, Graduate School

Committee: Not Provided (Other) Subjects: Engineering

Master of Science, The Ohio State University, 2016, Environment and Natural Resources

Soil erosion due to human activity impairs agricultural productivity and puts valuable wildlife habitat at risk for conversion into cropland. The present study sought to gain insight into the mechanisms of erosion through evaluating the erodibility of central Ohio soils under management regimes of contrasting intensity. Erodibility was examined at 2 adjacent agricultural fields managed for at least 10 years under respective regimes of no-tillage and conventional tillage (i.e., chiseling in the fall and disk harrowing in the spring). Measured soil properties included texture, organic carbon content, bulk density, wet aggregate stability, water-holding capacity, saturated hydraulic conductivity, residue coverage, and permanganate-oxidizable carbon content (POXC). Due to the temporal variability of many of these properties, measurements were carried out in both the spring and fall of 2014. In order to better isolate the impact of management regime on soil properties, both study fields were sampled according to landscape position (e.g., upland, lowland, and terrace), and comparisons between fields were performed primarily among samples matched in terms of both landscape position and season. Correlations among measures were also examined, and each field was additionally evaluated using 3 erosion assessment tools: the Universal Soil Loss Equation (USLE), the Revised Universal Soil Loss Equation 2 (RUSLE2), and a systems-engineering framework described by Karlen and Stott (1994). Significant differences (p < 0.05) between fields were found for most soil properties sampled within the same landscape position and season, and differences were most pronounced for aggregate stability and residue coverage. Correlations among properties revealed that organic carbon was well correlated with bulk density, water-holding capacity, and POXC, and weakly correlated with aggregate stability. POXC was slightly better correlated with aggregate stability than was organic carbon, but it st (open full item for complete abstract)

Committee: Brian Slater PhD (Advisor); Edward McCoy PhD (Committee Member); Steven Culman PhD (Committee Member) Subjects: Agriculture; Agronomy; Environmental Science; Soil Sciences

Master of Science, The Ohio State University, 2015, Environment and Natural Resources

The demand for food is expected to rise due to increases in world populations over the next decades. The use of heavy machinery to meet this demand for food is expected to increase as well. Additionally, soil compaction is recognized as a major concern in agriculture dependent on the use of heavy machinery. Soil compaction has been shown to negatively impact crop production, which may occur because of overuse of heavy machinery used in tillage operations, sowing, harvesting, and manure and fertilizer applications. Soil compaction also affects physical, chemical and biological processes occurring in the soil including the mineralization of soil organic carbon and nitrogen. Long-term experiments that include tillage and crop rotations are necessary to understand the impact of soil management practices on soil properties. Tillage practices (conventional tillage-CT; minimum tillage, MT; and no tillage, NT) and crop rotations (continuous corn- CC and corn-soybean-CS) effects on soil compaction and carbon and nitrogen were studied in the long-term Triplett-Van Doren plots which are part of the Ohio Agricultural Research Development Center (OARDC). These plots are experimental sites located in northeast Ohio (Wooster) and northwest Ohio (Hoytville).

Committee: Brian Slater (Advisor); Warren Dick (Committee Member); Edward McCoy (Committee Member); Rebecca Tirado-Corbala (Committee Member) Subjects: Soil Sciences

Master of Science, The Ohio State University, 2015, Plant Pathology

Corn fields in Ohio were surveyed in 2013 and 2014 to determine the frequency and abundance of plant-parasitic nematodes. Soil samples were collected at a depth of 40 to 50 cm from 425 fields when corn was between growth stages V3 and V6. A total of 15-16 fields were sampled in each of 28 counties, across 6 soil regions, representing three cropping systems and three tillage programs. Standard laboratory techniques were used for processing and extraction, and plant-parasitic nematodes were identified to genus. Nine commonly occurring morphological groups of plant-parasitic nematodes, namely spiral (Helicotylenchus spp.), lesion (Pratylenchus spp.), lance (Hoplolaimus spp.), dagger (Xiphinema spp.), stunt (Tylenchorhynchus spp.), pin (Paratylenchus spp.), ring (Criconemella spp.), stubby-root (Paratrichodorus spp.), and cyst (Heterodera spp.), along with several genera in the subfamily Tylenchinae counted together as “tylenchids”, were identified, with maximum individual-field population densities ranging from 26 to 1,164 nematodes/100 cm3 soil, depending on the group. Generalized linear mixed models were fitted to the data to estimate county-level heterogeneity in nematode presence, while binary and ordinal logistic regression models were fitted to estimate the odds of each genus being present, and the lesion, lance, spiral, and pin nematodes at potentially damaging population densities based on soil region, cropping sequence, tillage, and soil pH, silt content, and electrical conductivity. The spiral nematodes and tylenchids were detected in 94 and 96% of the fields, whereas the lesion, pin, lance, stunt, and dagger nematodes were recovered from 80, 57, 48, 48, and 37% of the fields, respectively. The stubby-root, cyst, and ring nematodes were the least frequent, each identified from fewer than 13% of the fields. County-level heterogeneity varied among the genera, with variance estimates ranging from 0.56 to 3.23. However, except for comparisons between the stunt an (open full item for complete abstract)

Committee: Pierce Paul Dr. (Advisor); Terry Niblack Dr. (Committee Member); Laura Lindsey Dr. (Committee Member) Subjects: Plant Pathology

Master of Science, The Ohio State University, 2012, Natural Resources

Agriculture and its environmental effects are topics of much interest. What role does agriculture play in atmospheric enrichment of CO2? What role can it play in sequestering atmospheric CO2? What data do we have to provide answers to the questions that are being asked? This thesis collates and evaluates data from long-term research plots in Wooster and Hoytville, to focus on specific ways agriculture effects the environment. First a database was created for the two research sites from a vast amount of data collected over the past 50 years at these sites. From this database a C budget was created to evaluate the effect of tillage (no-tillage - NT, chisel tillage - MT, and moldboard plow tillage - PT) and crop rotation (corn following corn - CC and corn following soybean - CS) on C enrichment of the atmosphere. At both sites, the CC rotation had C budgets that were significantly lower (by 10-20 Mg C/ha over the year time span) than the CS rotation. Wooster NT treatments were significantly lower than MT or PT (5-10 Mg C/ha/50 years), while for Hoytville MT and PT treatments were lower than NT by 15 Mg C/ha/49 years. Also studied, using current samples, was the effect tillage (NT and MT) and crop rotation (CC and CS) had upon greenhouse gas (GHG) emissions. GHG emissions were two times less at Hoytville than Wooster. At both sites the CC rotation produced more GHG emissions than did the CS rotation. The effect of tillage varied by gas and site, but overall GHG emissions from NT were less than MT for Wooster and NT was greater than MT for Hoytville. The combination of no-tillage and rotating corn with soybean generally produced less GHG emissions. When combined with the other benefits that have been found for combining no-tillage with crop rotations, this information leads to the conclusion that the adoption of both practices will lead to crop production and environmental benefits.

Committee: Warren Dick PhD (Advisor); Robert Mullen PhD (Committee Member); Brian Slater PhD (Committee Member) Subjects: Agriculture; Environmental Management; Environmental Science; Natural Resource Management; Soil Sciences

Doctor of Philosophy, The Ohio State University, 2005, Veterinary Preventive Medicine

Cryptosporidiosis, an infection caused by several genotypically and phenotypically diverse Cryptosporidium species, is a serious enteric disease of animals and humans worldwide. The current understanding of cryptosporidiosis, transmission, diagnosis, treatment and prevention measures for this disease is discussed. Contaminated water represents the major source of Cryptosporidium infections for humans. Manure from cattle can be a major source of Cryptosporidium oocysts. Oocysts transport to surface water can occur through direct fecal contamination, surface transport from land-applied manure or leaching through the soil to groundwater. Identification of Cryptosporidium species and genotypes facilitates determining the origin of the oocysts and to recognize sources of infection in outbreak situations and the risk factors associated with transmission. Very few studies have applied isolation methods to field samples because of difficulties with detection of oocysts in environmental samples. The objective of this study was to develop an easy method that can be applied to field samples to rapidly detect the presence of Cryptosporidium oocysts and identify their species. A molecular detection system that included an oocyst recovery method combined with spin column DNA extraction, followed by PCR-hybridization for detection and a Real-Time PCR-melting curve analysis for species assignment. Due to its versatility and capability of rapid high-throughput analysis of multiple targets, an oligonucleotide microarray was also designed to identify Cryptosporidium parasites and discriminate between species. The detection assay was then used to assess Cryptosporidium contamination in swine and poultry samples and to study the transport of Cryptosporidium oocysts through disturbed (tilled) and non-disturbed (no-till) soil during simulated rainfall. The results of the study demonstrated the potential of the assay for the detection of the parasite in environmental samples. In vitro cult (open full item for complete abstract)

Committee: Srinand Sreevatsan (Advisor) Subjects:

Doctor of Philosophy, The Ohio State University, 2004, Agricultural, Environmental and Development Economics

This dissertation explores the physical and economic aspects of agricultural externalities and the economic value of marine and stream recreational fishing. The first essay, Empirical Investigation of Agricultural Externalities: Effects of Pesticide Use and Tillage System on Surface Water Quality and Treatment Costs, focuses on the off-farm water quality and water treatment cost effects of agricultural practices, specifically on the pesticide contamination in finished public surface water and water treatment costs in the Maumee River Basin, a major tributary to Lake Erie, located in northwestern Ohio, northeastern Indiana, and southeastern Michigan. Findings are that average chemical cost per million gallons of water decreases by 1.95% for a 1% reduction in pesticide application, while pesticide contamination level decreases by 4.32% for a 1% more adoption of conservation tillage in a typical watershed area. The second essay, The Economic Value of Marine Recreational Fishing: Applying Benefit Transfer to Marine Recreational Fisheries Statistics Survey (MRFSS), conducts a comprehensive survey of benefit transfer. Then, benefit transfer technique is applied to the estimation of access value to fishing sites and willingness to pay for better fishing experience in a marine recreational fishing environment. Using 1994 Northeast and 1997 Southeast MRFSS data, benefit transfer estimates are compared with original value estimates. Although benefit transfer error could go up to over 400% of original estimates for some cases, the magnitude of benefit transfer error is less than 100% of original estimates for most cases. The third essay, Recreational Fishing Value Estimation of Water Quality Improvements in Western Ohio Using Benefit Transfer, presents methods for estimating the value of recreational fishing trips and water quality improvements in two watersheds supporting a warm freshwater recreational fishery, the Stillwater River Watershed and Maumee River Basin, in western (open full item for complete abstract)

Committee: Lynn Forster (Advisor) Subjects: