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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

Effects of climate and development on the hydrology and geomorphology of the Yellow Creek Watershed, Summit and Medina Counties, OH

Delaney, Adam J. January 2016 (has links)
No description available.
62

Physical and Chemical Controls on Natural and Anthropogenic Remediation of Two Streams Impacted by Acid Mine Drainage in the Raccoon Creek Watershed, Ohio

DeRose, Lisa M., L 26 July 2011 (has links)
No description available.
63

Environmental geology and land-use planning on the Big Darby Creek, Ohio, Watershed

Foley, Duncan January 1973 (has links)
No description available.
64

The effect of urbanization on the hydrologic regime of the Big Darby Creek watershed, Ohio

Ahn, Gi-Choul 30 August 2007 (has links)
No description available.
65

Comparison of two hydrological models on a Virginia Piedmont watershed

Fu, Youtong 04 May 2010 (has links)
KINEROS and PSRM-QUAL:J two distributed parameter event-based hydrologic models, were applied to Foster Creek Watershed, Louisa County, Virginia. The simulations of the two models were conducted using published data and a ten year database from the Foster Creek Watershed, Louisa County, Virginia. Data management and analysis was supported through the use of PC-VirGIS, a DOS based GIS package developed by the Information Support Systems Laboratory, Virginia Tech. The performance of the two models were based on the criteria established to compare the simulated and recorded peak discharge rates , total runoff volumes and time to peak. Goodness of fit criteria were based on graphic comparison relative error, model efficiency, linear regression, hypothesis testing and variance. Based on these measurements, the simulated results by both models were acceptable. KINEROS generally made better predictions of peak discharge rate and time to peak. Hydrograph shapes also generally matched the recorded sequence more closely. PSRM-QUAL simulated the total runoff volume slightly better than KINEROS. The sensitivity of KINER OS and PSRM-QUAL to the model input parameters was evaluated. For KINEROS, peak discharge rate and runoff volume were very sensitive to changes in rainfall amount, saturated hydraulic conductivity and effective capillary drive. For PSRM-QUAL, peak discharge rate and total runoff volume were very sensitive to changes in SCS CN, initial abstraction coefficient and rainfall amount. / Master of Science
66

Effect of Stakeholder Attitudes on the Optimization of Watershed Conservation Practices

Piemonti, Adriana Debora 30 January 2013 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Land use alterations have been major drivers for modifying hydrologic cycles in many watersheds nationwide. Imbalances in this cycle have led to unexpected or extreme changes in flood and drought patterns and intensities, severe impairment of rivers and streams due to pollutants, and extensive economic losses to affected communities. Eagle Creek Watershed (ECW) is a typical Midwestern agricultural watershed with a growing urban land-use that has been affected by these problems. Structural solutions, such as ditches and tiles, have helped in the past to reduce the flooding problem in the upland agricultural area. But these structures have led to extensive flooding and water quality problems downstream and loss of moisture storage in the soil upstream. It has been suggested that re-naturalization of watershed hydrology via a spatially-distributed implementation of non-structural and structural conservation practices, such as cover crops, wetlands, riparian buffers, grassed waterways, etc. will help to reduce these problems by improving the upland runoff (storing water temporally as moisture in the soil or in depression storages). However, spatial implementation of these upland storage practices poses hurdles not only due to the large number of possible alternatives offered by physical models, but also by the effect of tenure, social attitudes, and behaviors of landowners that could further add complexities on whether and how these practices are adopted and effectively implemented for benefits. This study investigates (a) how landowner tenure and attitudes can be used to identify promising conservation practices in an agricultural watershed, (b) how the different attitudes and preferences of stakeholders can modify the effectiveness of solutions obtained via classic optimization approaches that do not include the influence of social attitudes in a watershed, and (c) how spatial distribution of landowner tenure affects the spatial optimization of conservation practices on a watershed scale. Results showed two main preferred practices, one for an economic evaluation (filter strips) and one for an environmental perspective (wetlands). A land tenure comparison showed differences in spatial distribution of systems considering all the conservation practices. It also was observed that cash renters selected practices will provide a better cost-revenue relation than the selected optimal solution.
67

Nitrogen, Phosphorus and Carbon Dynamics during Storms in a Glaciated Third-Order Watershed in the US Midwest

Johnstone, Joseph A. 22 August 2013 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / The characterization of the nutrients nitrogen, phosphorus and carbon (NPC) export to streams during storms is an integral part of understanding processes affecting water quality. Despite the fact that excessive levels of these nutrients in the Mississippi River basin adversely affects water quality in the Gulf of Mexico, little research has been conducted on NPC dynamics during storms on larger (>20 km2) agriculturally dominated Midwestern watersheds. This project examined the storm export of nitrate, ammonium, total phosphorus, and dissolved organic carbon (DOC) in the upper Eagle Creek Watershed (UECW) (274 km2) in Central Indiana, USA. Water samples were collected during five winter and spring storms in 2007 and 2008 on the rising and falling limb of the hydrograph, in order to characterize NPC dynamics during storm events. Stream discharge and precipitation was monitored continuously, and major cations were used to examine changes in source water over the duration of the storm and assist in the determination of potential flowpaths. DOC, total P, and TKN (Total Kjeldahl Nitrogen) tended to peak with discharge, while nitrate usually exhibited a slight lag and peaked on the receding limb. Total phosphorus, NH3-, TKN, and DOC appear to be delivered to the stream primarily by overland flow. NO3--N appear to be delivered by a combination of tile drain and macropore flow. Overall UECW displayed smoother nutrient export patterns than smaller previously studied watersheds in the area suggesting that scale may influence nutrient export dynamics. Further research is underway on a 3000 km2 watershed in the area to further examine the role scale may play in nutrient export patterns.
68

Historical land use and its impact on Oak Creek, Oregon

Yamaguchi, Keiko, 1964- 15 June 1992 (has links)
The purposes of this study were: 1) to review the land use history of Oak Creek watershed since European settlement. And 2) to consider the human-caused impacts and their effects associated with different land uses. The study area was classified into three land use patterns: residential, agricultural, and forested areas. Since the European settlement in the mid 1840's, the Oak Creek watershed has experienced changes of land use simultaneous with the development of the city of Corvallis and its vicinity. Associated with this, different impacts have occurred on riparian areas. By and large, these impacts were inherent to each land use. / Graduation date: 1993
69

Impact of mine land reforestation and revegetation on water quality in a mid-Appalachian watershed a stream monitoring study /

Wei, Honghong, January 2008 (has links)
Thesis (M.S.)--West Virginia University, 2008. / Title from document title page. Document formatted into pages; contains viii, 92 p. : ill., maps (some col.). Includes abstract. Includes bibliographical references (p. 56-62).
70

Export of carbon, nutrients, and microbiological indicators in Beaver Creek Watershed, Tennessee

Chen, Si, January 2009 (has links)
Thesis (M.S.)--University of Tennessee, Knoxville, 2009. / Title from title page screen (viewed on Mar. 19, 2010). Thesis advisor: Qiang He. Vita. Includes bibliographical references.

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