Engineering Commons^™

Nitrate Removal And Placement Of Floating Treatment Wetlands In The Midwest, Mary G. Keilhauer

School of Natural Resources: Dissertations, Theses, and Student Research

The Midwestern United States is vulnerable to eutrophic conditions from high nutrient concentrations. Recommendations for nonpoint source pollution management include runoff treatment (i.e., filter strips, riparian buffers) and in-situ lake treatment practices (i.e., aluminum sulfate (alum) treatments, aeration, up/downdraft pumping, floating treatment wetlands). Floating treatment wetlands (FTWs) are an innovative wetland design for nutrient removal from nonpoint sources and provide a unique in-situ treatment. Best management practice studies have commonly focused on adjacent to water practices, which have resulted in a gap for guidance for in-situ treatment placement and design. Therefore, the objectives of this project were to (1) Quantify …

A Case Study Of Changing Cropping Diversity And Agricultural Risk In The Doulthabad Mandal Of Telangana State In India, Srikanth Kondabolu

School of Natural Resources: Dissertations, Theses, and Student Research

The Doulthabad^[1] Mandal is a hot semi-arid agro-ecological sub-region (Rao et al. 2006) located in Mahbubnagar District on the North Telangana Plateau in the state of Telangana. Agriculture is the main occupation in this region, which is populated mostly with small and marginal farmers. This study uses the time period from 1971 to 2004 to study the variation in cropping pattern diversity and distribution of rainfall during the monsoons and understand the implications on production risk in agriculture. Quantitative methods were used in determining the changes in rainfall while qualitative methods were used to study cropping system changes. The …

Quantifying And Modeling Stream-Aquifer Interactions In The Elkhorn River Basin, Nebraska, Can Liu

School of Natural Resources: Dissertations, Theses, and Student Research

This study combined statistical analyses, field investigations and numerical groundwater flow modeling to quantify the connectivity between the Elkhorn River and its adjacent aquifers in Nebraska. The Mann-Kendall trend tests were conducted to detect increasing or decreasing tendencies on the time series data of streamflow, which were collected from eighteen gauging stations in the Elkhorn River and its tributaries. Decreasing trends were not found in the annual streamflow data.

Field investigation of streambed hydraulic properties was performed in the Elkhorn River near Winslow and Norfolk. Vertical hydraulic conductivities (K_v) of the shallow streambed sediments were obtained by …