Doctor of Philosophy, The Ohio State University, 2022, Environmental Science

Accelerated erosion-induced topsoil loss threatens the productivity and sustainability of maize (Zea mays L.) cropping systems across the U.S. Corn Belt by adversely impacting soil health. The rehabilitation of soil health in eroded topsoil has been shown to improve with best management practices coupled with soil amendment application. The current study investigated the impact of simulated erosion and annual amendment application on soil health 20 years after establishment at two central Ohio sites (Waterman Farm: WF; Western Station: WS). Simulated erosion was employed in 1997 to create three incremental topsoil depths (TSD) (20 cm topsoil removed (TSD-0); 0 topsoil removed (TSD-1); 20 cm topsoil added (TSD-2). Annual application of three soil amendments (inorganic, synthetic N fertilizer (I); organic, compost manure amendment (O); no amendment (C)) were investigated for their ability to restore soil health in the surface 40 cm of these cropping systems. Increasing TSD resulted in more favorable physical, chemical, and biological soil health attributes primarily through enhanced soil structure, aggregation, water movement and storage, soil pH range, and SOC and soil N concentrations. The organic amendment proved most efficient in regenerating soil health at lower TSD levels and augmenting soil health in systems with greater TSD levels. Greater TSD usually resulted in greater C and N pools after two decades. However, this was variable at levels where greater TSD was present. Soils amended with the organic treatment always produced greater C and N stocks across both sites. The trends in SOC pools were TSD-1 ≥ TSD-2 > TSD-0 at the WF site and TSD-2 ≥ TSD-0 ≥ TSD-1 at the WS site. The trend in TN pools followed the same pattern as SOC pools at the WF site, but was TSD-2 ≥ TSD-1 ≥ TSD-0 at the WS site. Soils with greater TSD and those amended with the organic amendment were more resilient in the face of simulated rainfall and resulted in the smallest incurred losses of (open full item for complete abstract)

Committee: Rattan Lal (Advisor); Kristin Mercer (Committee Member); Steven Culman (Committee Member); Nicholas Basta (Committee Member) Subjects: Agriculture; Agronomy; Environmental Science; Soil Sciences; Water Resource Management

Doctor of Philosophy (PhD), Ohio University, 2016, Civil Engineering (Engineering and Technology)

Sedimentation is one of the important factors affecting stream channel stability. The estimation of sediment supply, assessment of channel stability, and potential influencing factors are of interest in this study. A proposed model was developed by the integration of Revised Universal Soil Loss Equation (RUSLE) model and Watershed Assessment of River Stability and Sediment Supply (WARSSS), aiming to estimate the sediment load and evaluate the channel stability of a man-made channel. The proposed model was applied to the channelized Hocking River near Athens, Ohio. It was estimated that the annual gross erosion from the watershed was 728,733,738 kg, 97% of which was from the surface erosion, while only 3% resulted from streambank erosion. The total sediment yield in the channelized Hocking River was indirectly estimated by the addition of suspended sediments and bedload sediments, which were directly measured in the channel. The total annual sediment yield was 80,991,718 kg, in which 98% was estimated from suspended sediments and 2% from bedload sediments. This resulted in a sediment delivery ratio of 11%, which was consistent with those of the watersheds having similar size in the studied region. The total sediment transport capacity was estimated by the proposed model to be 17,161,761 kg/yr. Compared with the total sediment yield of 80,991,718 kg, 21% of which was transported by the river flow. The majority of sediments deposited in the channel due to the insufficient transport capacity. The amount of sediment accumulated was indirectly verified by the annual dredging project conducted by the Hocking Conservancy District (HCD). The channel stability of the Hocking River near Athens, Ohio was assessed by the characteristics of soil erosion for each monitored reach. Based on the four categories of stability determinations, most of the studied reaches were unstable in the lateral direction and all the reaches had excess deposition except one of the downstream r (open full item for complete abstract)

Committee: Tiao Chang (Advisor); Wei Lin (Committee Member); Kurt Rhoads (Committee Member); Teruhisa Masada (Committee Member); Deborah McAvoy (Committee Member) Subjects: Civil Engineering; Water Resource Management

Doctor of Philosophy, The Ohio State University, 2004, Soil Science

Soil quality indices are useful tools for assessing agronomic/ biomass productivity and ascertaining temporal changes in soil properties in relation to land use and management. This study was conducted in the Lake Victoria region in Masaka, Uganda to: (a) identify key soil properties that impact soil quality and agronomic productivity; (b) evaluate soil quality-management inter-relationships; (c) evaluate the use of soil reflectance as a soil quality indicator, and (d) determine the cost and returns of different cropping systems. Bulk and core soil samples were collected from the 0-20 and 20 – 50 cm depths, from the farmers' fields, in order to determine soil organic carbon, nitrogen, calcium, phosphorous, magnesium, pH, _13C, _15N, coarse fragments, soil bulk density and soil texture. Saturated hydraulic conductivity (Ks) was determined in the field using a tension infiltrometer and soil depth using an auger. The soil degradation rating was assessed by assigning parametric values to levels of SOC, soil bulk density, Ks, soil texture, soil pH, soil depth and the proportion of coarse fragments in the top soil and these parameters were utilized to develop a single index. Air dry samples were scanned using a spectrometer and the first derivative of the spectral data was calibrated against the measured soil properties. Results indicated that soil quality was affected by SOC, soil depth and Ks. No direct effects of management on soil quality were discerned. Good predictions of several soil properties were obtained using the spectral data. Although a majority of farmers planted bananas as the first choice crop, the highest net returns were obtained from coffee while the highest costs were measured for bananas implying that food self sufficiency was the major determinant of the choice of crop to be grown. It was recommended that grasslands must not be converted to agricultural land use because of their high susceptibility to soil degradation and that farmers be sensitized (open full item for complete abstract)

Committee: Rattan Lal (Advisor) Subjects:

Master of Science, University of Akron, 2024, Civil Engineering

Compost blankets have been used as a management practice over highway slopes, especially with disturbed soils, to mitigate runoff and soil erosion. However, it is yet to be employed in Ohio due to lack of research and specifications. This research focused on efficiency of 1”, 1.5” and 2” of Biosolids and Yard-waste compost blanket over 6:1 and 4:1 slope of disturbed soil in a lab-scale rainfall simulation, followed by field study on 1.5” Biosolids and Yard-waste. The assessment of vegetation coverage showed that Biosolids significantly outperformed both Yard-waste and control treatments (p<0.05). Grass density and health were notably better in Biosolids, although increasing compost thickness did not proportionally improve vegetation growth. Both Biosolids and Yard-waste effectively reduced runoff generation, with 2” Biosolids performing the best by reducing runoff volume by 96% to 98%. Compost blankets reduced total suspended solids (TSS) significantly compared to controls (p<0.05), particularly 2” Biosolids, which released the least TSS with almost 99.99% reduction. For Soluble Reactive Phosphorus (SRP), 2” Biosolids were the most effective treatment in reducing losses by 92% to 96% than control cases. Nitrate loss was not significantly reduced by any treatments on the 6:1 slope, but 1.5” Yard-waste (98%-99% reduction) and 2” Biosolids (86%-95% reduction) performed better than other treatments on the 4:1 slope. Both Biosolids and Yard-waste showed reduced Total Nitrogen (TN) and Total Potassium (TK) release compared to controls. With 98% to 100% TN reduction, 1” Yard-waste performed better than other treatments in both slopes. For TK, 1.5” Yard-waste had the highest reduction of 91% in 6:1 slope, but for 4:1 slope it was 1” Yard-waste with 84% reduction. Field tests compared 1.5” Biosolids and 1.5” Yard-waste with vegetated and unvegetated control cases, which demonstrated healthy vegetation growth in Biosolids within six weeks, requiring trimming to adhere to guid (open full item for complete abstract)

Committee: Teresa Cutright (Advisor); Ala Abbas (Committee Member); David Roke (Committee Member); Nariman Mahabadi (Committee Member) Subjects: Civil Engineering; Engineering; Environmental Engineering; Experiments; Geotechnology

Master of Science, The Ohio State University, 1979, Graduate School

Committee: Not Provided (Other) Subjects:

Ph.D., Antioch University, 2018, Antioch New England: Environmental Studies

Climate change and crop intensification are key challenges to the livelihoods and wellbeing of the majority of rural smallholder farmers in developing countries, particularly in human-dominated, climate-sensitive landscapes such as the northern highlands of Rwanda where issues of fluvial floods, soil erosion pose serious threats to the livelihoods of smallholder farmers. In this mixed methods study conducted between August and December 2015, I explored smallholder farmers' perceptions by examining what barriers might hinder the process of agroforestry adoption by smallholder farmers, what socio-economic and physical factors and attitudes influence crop choices, motivations for smallholder farmers' willingness to plant trees within riparian buffer zones and opportunities and challenges to the establishment of riparian buffer zones that maintain ecosystem services. Results indicate that challenges to adoption of agroforestry to support climate change adaptation and food security in Rwanda are related to land scarcity, poverty, limited technological and financial capacity among most smallholder farmers, limited engagement of smallholder farmers in agroforestry research and an inclination for short term benefits that could hinder adoption of agroforestry which has a long term investment. Most smallholder farmers believed that the onset of short rains comes earlier in recent years compared to more than ten years ago. In response, most farmers reported that they plant crops earlier in the season. Results from rainfall analysis, although not conclusive, show a shift in rainy day frequency. Respondents who strongly agreed that soil erosion within farms proximal to streams is a serious threat were more likely to support the idea that establishing a riparian buffer would help entrap sediments and mitigate soil erosion within farmlands adjacent to streams. However, farmers reported that establishing a functional riparian buffer requires engagement with extension services, fi (open full item for complete abstract)

Committee: Beth Kaplin Ph.D. (Committee Chair); James Gruber Ph.D. (Committee Member); Joel Hartter Ph.D. (Committee Member) Subjects: Agriculture; Environmental Management; Environmental Science; Environmental Studies; Forestry; Water Resource Management

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

Doctor of Philosophy, The Ohio State University, 1996, Graduate School

Committee: Not Provided (Other) Subjects: Agriculture

Doctor of Philosophy, The Ohio State University, 1985, Graduate School

Committee: Not Provided (Other) Subjects: Engineering

Doctor of Philosophy, The Ohio State University, 1985, Graduate School

Committee: Not Provided (Other) Subjects: Economics

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

Committee: Not Provided (Other) Subjects: Agriculture

Doctor of Philosophy, The Ohio State University, 1981, Graduate School

Committee: Not Provided (Other) Subjects: Engineering

Doctor of Philosophy, The Ohio State University, 1981, Graduate School

Committee: Not Provided (Other) Subjects: Economics

Doctor of Philosophy, The Ohio State University, 1977, Graduate School

Committee: Not Provided (Other) Subjects: Agriculture

Doctor of Philosophy, The Ohio State University, 2016, Food, Agricultural and Biological Engineering

In recent years, the digital world has experienced an explosion in the magnitude of data being captured and recorded in various industry fields. Accordingly, big data management has emerged to analyze and extract value out of the collected data. The traditional construction industry is also experiencing an increase in data generation and storage. However, its potential and ability for adopting big data techniques have not been adequately studied. This research investigates the trends of utilizing big data techniques in the construction research community, which eventually will impact construction practice. For this purpose, the application of 26 popular big data analysis techniques in six different construction research areas (represented by 30 prestigious construction journals) was reviewed. Trends, applications, and their associations in each of the six research areas were analyzed. Then, a more in-depth analysis was performed for two of the research areas including construction project management and computation and analytics in construction to map the associations and trends between different construction research subjects and selected analytical techniques. In the next step, the results from trend and subject analysis were used to identify a promising technique, Artificial Neural Network (ANN), for studying two construction-related subjects, including prediction of concrete properties and prediction of soil erosion quantity in highway slopes. This research also compared the performance and applicability of ANN against eight predictive modeling techniques commonly used by other industries in predicting the compressive strength of environmentally friendly concrete. The results of this research provide a comprehensive analysis of the current status of applying big data analytics techniques in construction research, including trends, frequencies, and usage distribution in six different construction-related research areas, and demonstrate the applicability an (open full item for complete abstract)

Committee: Qian Chen Dr. (Advisor) Subjects: Civil Engineering; Comparative Literature; Computer Science

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

PhD, University of Cincinnati, 2014, Engineering and Applied Science: Environmental Engineering

Events of rainfall have been reported to result in increased concentrations of biological and chemical contaminants transported through streams and channels. The heterogeneous distribution of the contaminants in time and space presents interesting modeling challenges. Incorporating and pinpointing sources of increased microbial contribution to our water bodies would effectively help in the decision making process. There are many factors and unknown processes that we still do not fully understand and are not able to describe using deterministic approaches and methods. One way to account for these uncertainties is by utilizing well established stochastic based models to be able to predict the risks that might result from increased microbial influx to our recreational water systems. The goal of this work was to develop a new, GIS-integrated stochastic framework to model the fate and transport of microbial pollutants in surface waters. The resulting tool is intended for assessment of the spatial and temporal distribution of microbial water contamination risk during and following individual storm events on the watershed scale. As part of the work, a new data management system (DMS) was developed and tested. The DMS focuses primarily on standardizing hydrological data for easy access to facilitate sharing. All steps that were taken to setup and populate the Observations Data Model are described. After completion of the DMS, a framework that enables modeling and prediction of microbial concentrations and behaviors during individual rainfall events was developed based on a ArcGIS tool called the Schematic Processor. This framework was developed to include both a stochastic model and a soil erosion model to provide a more accurate picture of concentrations in time and space. The resulting new model contains expanded capabilities that incorporate contaminant interactions with suspended sediments in hillslopes and channels, thus providing time series of concentration (open full item for complete abstract)

Committee: Lilit Yeghiazarian Ph.D. (Committee Chair); William D Shuster Ph.D. (Committee Member); Timothy L Whiteaker Ph.D. (Committee Member); Margaret Kupferle Ph.D. P.E. (Committee Member); George Sorial Ph.D. (Committee Member) Subjects: Environmental Engineering

Master of Science in Engineering, Youngstown State University, 1999, Department of Chemical, Civil and Environmental Engineering

The problem of soil erosion and sediment runoff in the Indian Run watershed (area 11,277 acres), a major tributary to Mill Creek, is of serious concern to the Mill Creek Metroparks management and the Youngstown metropolitan area community. Mill Creek is primarily responsible for sediment deposition in Lake Newport that continues at an alarming rate. A nonpoint source simulation was performed for the Indian Run watershed using the Agricultural Nonpoint Source Pollution Model (AGNPS) water quality model with a focus on the problems of soil erosion and sediment yield. Four hypothetical storm conditions were simulated: (i) 3 in. precipitation of 6 hour duration, (ii) 2 in. precipitation of 4 hour duration, (iii) 1 in. precipitation of 1 hour duration, and (iv) 1 in. precipitation of 12 hour duration. Sensitivity of the results to changes in P, C, and K factors in the Universal Soil Loss Equation was evaluated. Using the model results, the mean flow, erosion and sediment yield for the watershed outlet on a yearly basis were estimated to be on the order of 0.944 cfs/sq. miles, 13.4 tons/acre, and 1100 tons, respectively, which compare favorably with the field measurements. The AGNPS simulation identifies five cells (each 179 acres in area) that are primarily responsible for the problems of soil erosion, and sediment deposition in the entire Indian Run watershed. The sediment deposition and the flow rate predictions are within 10% of the measurements reported [MBR-HER, 1994]. The AGNPS simulation of the watershed provides information that could be of considerable help in formulating management decisions to address the problem of sediment deposition in Lake Newport.

Committee: Scott Martin (Advisor) Subjects: Engineering, Environmental

Master of Science (MS), Ohio University, 2012, Civil Engineering (Engineering and Technology)

This project utilized a Geographic Information System to model soil erosion potential in the Muskingum Watershed using the Revised Universal Soil Loss Equation (RUSLE). The project had three objectives; identify erosion “hotspots” in the Muskingum Watershed, test the applicability of RUSLE in large drainage basins such as the Muskingum Watershed, and study the erosion potential of ten subwatersheds within the Muskingum Watershed. The average erosion potential for the Muskingum Watershed was 0.290 kg/m2/year, and the average erosion potentials for the sub-watersheds ranged from 0.197 kg/m2/year to 0.804 kg/m2/year. The hotspot erosion value for the Muskingum Watershed was 1.286 kg/m2/year.

Committee: Tiao Chang (Advisor) Subjects: Civil Engineering

Master of Science (MS), Ohio University, 2012, Civil Engineering (Engineering and Technology)

The objective of this study is to determine the relationship between soil erosion and sedimentation within Wills Creek, Senecaville Lake, and Salt Fork watersheds of Ohio. Both Senecaville Lake and Salt Fork Lake watersheds are entirely located within the watershed of Wills Creek Lake. Experimental results using the Revised Universal Soil Loss Equation and a sediment delivery equation in conjunction with Geographic Information Systems are compared to sedimentation reports prepared by the United States Army Corps of Engineers. Results of this comparison show that the type of land cover has the highest impact on the amount of soil erosion, specifically the lands associated with cultivated crops. Furthermore, the sediment yield of a watershed is not accurately calculated based on average annual sedimentation and present RUSLE erosion potential.

Committee: Tiao Chang PhD (Advisor); Teruhisa Masada PhD (Committee Member); Lloyd Herman PhD (Committee Member); James Dyer PhD (Committee Member) Subjects: Civil Engineering