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

Committee: Not Provided (Other) Subjects:

Master of Arts (MA), Ohio University, 2024, History (Arts and Sciences)

After the Second World War, Green Revolution techniques were introduced in West Africa to improve agricultural production and reduce poverty. Unlike in Asia and Latin American countries, the techniques in West Africa proved unsuccessful largely because of environmental and political hindrances. In recent years, few West African historians have shown interest in the region's agricultural history, especially during the early post-colonial period. The existing scholarship ignores the several agricultural programs introduced by, for instance, the Gambian government, whose aim was to enhance crop production and boost agricultural exports. Several agricultural schemes were introduced in the Gambia, but these projects appear to have exacerbated rural challenges, including gender inequality and landscape changes. Devastating droughts were also a common occurrence that worsened the situation. Disease outbreaks also devastated the livestock industry. To date, no study has examined why the ox-plows and Mixed Farming Centers of the 1960s and 1970s introduced in rural farming communities failed to yield the desired results. My project intends to investigate the impact of some of these projects, and the reasons for their failure. It also examines how environmental and climatic factors during this period contributed to the disruption of Gambian farming communities.

Committee: Assan Sarr (Advisor); Paul Milazzo (Committee Member); Katherine Jellison (Committee Member) Subjects: African History; Agriculture; Animal Diseases; Gender; Technology

Master of Science in Mechanical Engineering, Cleveland State University, 2023, Washkewicz College of Engineering

Most of the rain that falls over land, falls over forests, which cover approximately one-third of global land surface. Significant immediate and wide-ranging impacts are exerted on hydrological, ecological, and societal systems due to canopy-rainfall interactions, altering rainwater supply to the surface. All storm-related hydrological processes are impacted by the relative rates that canopy surfaces retain, evaporate, and redistribute rain. Many forest canopies host a community of plants called epiphytes that are generally capable of storing and evaporating substantial water. Epiphytes are comparatively under-researched regarding their role in rainfall partitioning compared to bark and leaves. Skidaway Island in Savannah, Georgia, has a forest canopy that hosts an epiphyte community consisting primarily of these three groups on a single host tree species, Quercus virginiana (southern live oak). The objective of this research was to determine the amount of time the study epiphytes were saturated, the amount of rainfall evaporated by the epiphytes, and the amount of condensation received by the epiphytes. It was found that saturation time had a positive relationship with Pleopeltis and detritus biomass, and decreased with Tillandsia. An indirect positive relationship between Pleopeltis and detritus biomass with evaporation and condensation amounts was observed.

Committee: John Van Stan (Advisor); Yong Tao (Committee Chair); Michael Gallagher (Committee Member) Subjects: Environmental Science; Mechanical Engineering

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

MA, Kent State University, 2020, College of Arts and Sciences / Department of Geography

Rainfall components likely differ in the magnitude and direction of their long-term changes for any given location, and some rainfall components may carry a greater regional signal of rainfall change than rainfall totals. This study, therefore, sought to evaluate the magnitude of change of each rainfall component relative to other components, and the greatest locations or regions of change across all the rainfall components in West Africa. Hourly rainfall data from the ERA5 reanalysis dataset was used to derive twelve rainfall components, which were evaluated for long-term means, interannual variability and long-term changes. The spatio-temporal magnitude of changes among the components was estimated using absolute z-score values of the slopes of each component and the count of significant grid-point trends. Teleconnections with ENSO were also assessed for each rainfall component and each region (within each rainfall component). Rainfall components were mostly similar in the spatial patterns of long-term means and interannual variability, but considerable differences exist in the spatial pattern of long-term trends. For rainfall totals and heavy rainfall frequency, the central Sahel is witnessing increasing trends while the western Sahel is experiencing significant decreasing trends, and this dichotomy has been widely reported in the literature. In general, decreasing trends predominate in the study area, especially in the northwestern Congo Basin, where annual rainfall is decreasing by 120mm per decade. Rainfall frequency accounts for 62% of all significant grid-point trends for the whole domain. In contrast, rainfall totals account for 27% of all combined significant trends across the domain, while rainfall intensity (4.6%), rainfall timing (5.2%), and rainfall seasonality (1.2%) account for the remaining signals of change. Most of the changes among the rainfall components are in the Tropical Wet and Dry regions (59% of all significant trends); the Saharan and Equ (open full item for complete abstract)

Committee: Cameron Lee PhD (Advisor); Scott Sheridan PhD (Committee Member); Tom Schmidlin PhD (Committee Member) Subjects: Climate Change; Geography

Master of Science in Engineering, University of Akron, 2020, Civil Engineering

Lake Erie is a drinking water source for millions of people and therefore requires protection from anthropogenic impacts. Nine percent of Lake Erie's freshwater comes from its tributaries. These sources should deliver clean water to the lake and thus warrant stewardship. Today, nonpoint sources emanating from agricultural and urbanized tributary watersheds are responsible for nutrient pollution loads to the lake and its tributaries. This thesis focused on the existing water quality parameters (nutrients and water chemistry) throughout the Euclid Creek watershed, an urbanized Lake Erie headwater tributary east of the Cuyahoga River. Field sampling was conducted from March 2019 to March 2020 at 14 sites with 23 dry weather collections and 11 wet weather collections. Results suggest that the 2019 annual phosphorus load entering Lake Erie was 22,600 pounds, over four times the target of 5000 pounds. Multiple upstream sites were the major nonpoint sources of nutrient pollution. Four locations averaged phosphorus levels 12 to 15 times the target of 0.05 mg/L, with two in the East Branch and two in the Main Branch. The main cause of the pollution pointed to leaky sanitary sewers. Like many urbanized areas throughout the United States, the original headwaters have been replaced by underground stormwater infrastructure. Due to the high level of connectivity between the creek and the storm sewer network, Euclid Creek responds rapidly to rainfall. There was evidence of Combined Sewer Overflow (CSO) and Sanitary Sewer Overflow (SSO) activations during storm events downstream of the confluence of the two branches and in the East Branch. Seasonally, spring storms contributed the most pollution during the monitoring period. The presence of the Cleveland Metroparks significantly reduced [p<0.05] nutrients during dry weather. Residential areas contributed more pollution than the three golf courses and the regional airport located within the watershed. The East Bran (open full item for complete abstract)

Committee: Teresa Cutright (Advisor); Stephen Duirk (Committee Member); Richard Einsporn (Committee Member) Subjects: Civil Engineering; Environmental Engineering

Doctor of Philosophy, The Ohio State University, 1987, Graduate School

Committee: Not Provided (Other) Subjects: Engineering

Doctor of Philosophy, The Ohio State University, 1983, 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, 1982, Graduate School

Committee: Not Provided (Other) Subjects: Hydrology

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

Committee: Not Provided (Other) Subjects: Agriculture

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

Committee: Not Provided (Other) Subjects: Agriculture

BA, Oberlin College, 2014, Geology

This paper looks at the dynamic interphase connecting post-revolutionary politics, modern land use practices, precipitation patterns, basin slope, and sediment yield records in Weixi basin, a small mountainous watershed in Southwestern China with a total upstream area of 198 m2. The goal is to identify what processes, climatic or not, account for the changes in local sediment yield and erosion budget. Weixi basin has an average annual sediment yield of 175 ton/km2 with two anomalously large peaks in 1979 and 1984. Precipitation is moderately correlated with sediment yield at interannual scale. It also affects seasonal fluctuations in sediment yield as major sediment loading events correspond to spring snowmelt and monsoon rainfall. However, there is no long-term trend in precipitation that could explain the peak in sediment yield. Land use/land cover classification shows an average of 22.8% bare land in Weixi basin, but no definitive conclusion about temporal changes could be drawn yet due to the discrepancy in imagery resolution. Short-lived radionuclide analyses show there is no correlation between upstream land use and depth of erosion, whereas slope is a moderate control for erosion depth.

Committee: Amanda Schmidt (Committee Chair); Karla Parsons-Hubbard (Committee Member); Carlo Demarchi (Committee Member) Subjects: Geology; Geomorphology

Master of Science, The Ohio State University, 2014, Civil Engineering

Understanding the complex processes that control soil water and rooting interactions in the vadose zone impacts the way we approach urban development, agriculture, and land use management. Complexities caused by heterogeneities in vadose zone characteristics can control not only hydrologic cycles, but ecologic and biogeochemical cycles as well. However, due to these heterogeneities and the difficulty of reliable subsurface measurements, the dominant processes of the vadose zone remain largely unknown. Small-scale differences in these vadose zone processes, such as infiltration, rooting behavior, nutrient mineralization, are often ignored in large-scale modeling, can have impacts at the watershed or ecosystem scale. As a result of increased climate variability, rainfall characteristics are expected to change worldwide. These variations in rainfall characteristics will present problems in agricultural areas that are dependent on a consistent supply of water. In the face of increasing water scarcity, the development of crop hybrids, that are resistant to drought, as well as other environmental stresses, is an important step in securing the long term viability of agriculture. The plasticity of root architecture to heterogeneities in the vadose zone in order to take advantage of these heterogeneities is largely unknown, but these processes can have a huge impact on a crops resistance to environmental stresses, such as drought. This study designs a controlled, small-scale experiment using two-dimensional tanks to study the early growth and root architecture of two maize hybrids, a drought tolerant and a drought susceptible hybrid. However the laboratory setup can easily be modified to study the vast array of uncertainties within the vadose zone. The maize hybrid study incorporated a variable intensity rainfall simulator, lighting and temperature control, soil moisture sensors, and soil coring to quantify root development. This study subjected the tw (open full item for complete abstract)

Committee: Gajan Sivandran PhD (Advisor); Ethan Kubatko PhD (Committee Member); Gil Bohrer PhD (Committee Member) Subjects: Civil Engineering; Environmental Engineering

MA, University of Cincinnati, 2013, Arts and Sciences: Geography

In this research, a cell-based model of the Las Vegas Wash (LVW) Watershed in Clark County, Nevada, was developed by combining traditional hydrologic modeling methods (Thornthwaite's water balance model and the Soil Conservation Survey's Curve Number method) and pixel-based computing technology. After the model was calibrated and validated, it was used to predict hydrologic conditions in 2030 and 2050 under future changes in climate and land use. The future climate projection was based on the Intergovernmental Panel on Climate Change (IPCC) Annual Report 4 (AR4) B1 climate scenario, and the land use change scenario was derived from a CA-Markov land use model. Results indicate that future total surface runoff in the watershed will significantly decrease in winters but increase in summers. While urban development can increase the amount of runoff, the primary factor in determining the amount of total surface runoff in the future is climate change. This finding may be useful to city planners and resource managers in devising future urban development plans and water management policies.

Committee: Tak Yung Tong Ph.D. (Committee Chair); Jeffrey Yang Ph.D. (Committee Member); Kevin Raleigh Ph.D. (Committee Member) Subjects: Hydrology

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:

Master of Arts (MA), Ohio University, 2004, Geography (Arts and Sciences)

To explore the signature pattern between sea surface temperature (SST) and summer monsoon rainfall in Bangladesh, the study examined 90 years (1912-2001) of monthly rainfall data for twelve stations for the months of May (pre-monsoon month), and June through September (monsoon months) and SST of the Bay of Bengal for the period of 1912 through 2001 at 2° by 2° grid cells. The total number of observation for each station was 450. In order to understand and explore the notion of the signature, two classical statistical methods, Principal Component Analysis and Canonical Correlation Analysis, were used to analyze the data. For data analysis and graphics, statistical software package SPSS and S-Plus programming environment were used. Also, mapping softwares ArcView, ArcGIS and ArcCatalog were used for making maps in order to show the results of each criteria variable. There is a significant positive (0.64) relationship between the All-Bangladesh Monsoon Rainfall (ABMR) and SST over the Bay of Bengal in the month of June. Any other monthly correlation was not found to be significant, although the overall correlation (i.e., May through September) existed between the SST and ABMR. They were poorly correlated. The SST over the Bay of Bengal was positively correlated with the June rainfall in Bangladesh, especially highly correlated with the Comilla station. The SST over the Bay of Bengal was important at 89°, 93°, and 95° longitudes for predicting the June rainfall in Bangladesh. The prevailing wind had a south-easterly component at this station. This is due to the deflection of the wind caused by the coastal hills. The orographic effect in the east and north-eastern part of the country enhanced the rainfall amount in that area. The correlations between the SST and monsoon rainfall in Bangladesh for the months of May, July, August, and September were found to be zero. Neither of the canonical correlations was found significant at the 95 percent or the 99 percent level. From (open full item for complete abstract)

Committee: Ronald Isaac (Advisor) Subjects: Geography

Master of Environmental Science, Miami University, 2011, Environmental Sciences

Combined sewer overflows (CSO) associated with antiquated combined sewer systems (CSS), contribute to water and ecosystem impairment in many older cities throughout the United States. This report examines the effectiveness of a green infrastructure pilot program in reducing CSOs and also analyzes the attitudes of residents who participated in the program. This study focuses on the use of green infrastructure (rain barrels) within two CSO basins in Wyoming, Ohio. Methods include the use of GIS, a resident survey and a rainfall and runoff model. Although the Wyoming Green Infrastructure Pilot Program was not effective at reducing CSO, survey results indicated that the property owners who participated in the study generally had a positive experience with the program. This report also discusses the limitations of the study and provides suggestions for improved methods on future studies.

Committee: William H. Renwick PhD (Advisor); Sandra Woy-Hazleton PhD (Committee Member); Robbyn J.F. Abbitt (Committee Member) Subjects: Conservation; Environmental Engineering; Environmental Management; Environmental Science; Environmental Studies; Water Resource Management

Master of Science, University of Akron, 2012, Geography-Geographic Information Sciences

In this study annual, seasonal and monthly series for total precipitation are analyzed to find increasing or decreasing trends in rainfall over space and time in Puerto Rico from 1956 to 2010. The precipitation series were observed at forty meteorological stations scattered over the island of Puerto Rico. The groups of series were selected for their spatial and temporal representativeness. In order to detect possible trends in precipitation over the island, the Mann-Kendall test was applied to the annual, seasonal and monthly series. This test is non-parametric and thus, has the advantage of being insensitive to the true (unknown) form of the distribution involved. The Mann-Kendall statistical test results of this research have shown that statistically significant increasing and decreasing trends occurred on some locations in the island of Puerto Rico from 1956-2010. The spatial and temporal distribution of the trends vary from increasing trends in the southwest, central and northeast regions for the annual series and dry season months to decreasing trends for the early wet season months mainly in the western area of the island. The results show that increasing trends occurred in the months of January, March, April, September and October mainly in the southwest and northeast and decreasing trends dominated in the months of May, July, August, November and December mainly in the west.

Committee: Linda Barrett Dr. (Advisor); Thomas Schmidlin Dr. (Advisor); John Szabo Dr. (Committee Member) Subjects: Atmospheric Sciences; Climate Change; Geography; Physical Geography