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

Agricultural nutrient pollution is a significant cause of impairment in American surface waters. Wetland restoration projects in agricultural watersheds can provide an effective sink for excess nutrients and potentially improve downstream water quality. Ohio University has partnered with The Stream and Wetlands Foundation to conduct water quality monitoring during the restoration of Bloody Run Swamp, a wetland in a former agricultural field near Columbus, Ohio. This thesis serves as an analysis of the initial water quality impacts of this restoration project. The restoration of Bloody Run Swamp did not significantly impact total dissolved phosphorus, orthophosphate, TKN, or ammonia concentrations. In contrast, both nitrate/nitrate and total dissolved nitrogen concentration and loads were significantly reduced during construction. This may have been due to the dry weather during construction and the removal of drainage tiles from Bloody Run Swamp. Future water quality monitoring is needed to determine the long-term impacts of this restoration project.

Committee: Natalie Kruse Daniels (Advisor); Gregory Springer (Committee Member); Morgan Vis (Committee Member) Subjects: Agriculture; Aquatic Sciences; Biology; Earth; Ecology; Environmental Engineering; Environmental Management; Environmental Science; Environmental Studies; Geomorphology; Hydrologic Sciences; Hydrology; Limnology; Water Resource Management

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

Intensive farming practices have led to the release of sediments and nutrients, primarily nitrogen and phosphorus, into the environment, which account for nearly half of all water pollution issues in the United States. Among the affected areas is the Bloody Run Swamp in Ohio, an historical swamp drained for agricultural purposes. A restoration project being undertaken by the Stream and Wetlands Foundation aims to retain water, sediments and nutrient on the 80-acre site by restoring the former wetland and constructing a natural channel design channel to replace the ditch to the north of the site. In this study, the pre-construction and during-construction hydrology and sediment concentration at seven sites were assessed to see the impact of the stream restoration and wetland construction aimed at reducing nutrient and sediment pollution. Water samples were gathered and assessed for total dissolved solids (TDS), total solids (TS), and total suspended solids (TSS). While the construction period was wetter than the pre-construction period, there were periods of sediment transport. Most sediments were transported at TDS rather than TSS, with TSS concentrations increasing with large runoff events. The results suggest that the restoration project aimed at reducing nutrient and sediment pollution in the Bloody Run Swamp has the potential to be effective.

Committee: Natalie Kruse Daniels (Advisor); Kelly Johnson (Committee Member); Sarah Davis (Committee Member) Subjects: Environmental Engineering; Environmental Science; Environmental Studies; Hydrology; Sedimentary Geology

Master of Arts, The Ohio State University, 2018, East Asian Studies

Since the 1960's China's agricultural system has gone through drastic changes. Modernization of this system necessitated adoption of key innovations, including new seed varieties, farm management practices, and the use of chemical fertilizers and pesticides. This thesis examines the impacts of three major transformations of China's agricultural economy, including the Socialist Period, the Green Revolution, and the Reform Period. A production function was used to estimate the effect of different agricultural inputs, regions, and decades for China's provincial grain production, including wheat, maize, and rice. The ordinary least squared estimates demonstrate the changes in China's agricultural system in this period. The North China Plain's (NCP) agricultural system was used as a case study, and demonstrated the changes in intensity of grain production from 1960-2016. Increasing chemical fertilizer use was found to be the most important change in China's agricultural inputs, as changes in other inputs such as land, labor, and agricultural machinery were constrained. Chemical fertilizer use was found to be more effective for grain production in the NCP compared to other provinces. However, high or poorly balanced chemical fertilizer applications in this region has important environmental health consequences. This fertilizer intensive production is reinforced by Chinese farmers' needs for ensured income and management practices introduced during the Green Revolution. China's environmental policy has had limited success in addressing these problems.

Committee: Karen Mancl (Committee Chair); Hongtao Yi (Committee Member); H. Allen Klaiber (Committee Co-Chair); Sathya Gopalakrishnan (Committee Member) Subjects: Agricultural Economics; Agriculture; Asian Studies