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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.
221

The Impact of Low Dissolved Oxygen and Recovery Patterns of Benthos in Northern Rivers

Rychywolski, Kasper M Unknown Date
No description available.
222

An experiment in land use mapping in the Three Rivers District, Natal.

Christopher, A. J. January 1965 (has links)
No abstract available. / Thesis (M.A.)-University of Natal, Durban, 1965.
223

The surface waters of Winnipeg: rivers, streams, ponds and wetlands 1874-1984: the cyclical history of urban land drainage

Graham, Robert Michael W. 02 March 2012 (has links)
ABSTRACT The modern day City of Winnipeg is situated on the poorly drained floor of pro-glacial Lake Agassiz, one of the flattest regions on earth. Within the area now bounded by the Perimeter Highway sixteen major streams and at least twenty small coulees once emptied into the Àssiniboine and Red Rivers. Behind the levees of these rivers large areas of marsh existed providing detention storage of surface waters. The overflow from these wetlands fed many of the streams. The first settlers in the region mimicked the natural drainage regime by damming the waters of the streams to drive grist mills. Later agricultural settlers, occupying the uninhabited but marginally drained lands behind the levees began to drain the wetlands. During the explosive growth period of the City (1880-1910) the drainage regime was radically altered and an expensive and inadequate conduit system was substituted in it's place. Serious flooding episodes have occurred from the first alterations up to the present day. In an attempt to solve the flooding problems, overcome the expense of conduit systems and add amenity, a series of stormwater retention ponds was introduced by private developers in 1965. Functually these impoundments imitate the original hydraulic relationship between the ponds, wetlands and streams of the native landscape. Approximately on hundred years after the elimination of the natural drainage regime, Plan Winnipeg 1981 calls for the preservation of all natural watercourses in recognition of their high value for storm drainage and recreational amenity. Of the original thirty-six streams and coulees only nine exist today. All wetland storage areas have been eliminated. This practicum traces the historical progression of land drainage in the City of Winnipeg, summarizes the design criteria for future urban stormwater management, and outlines the present condition and rehabilitation of the historic water features.
224

Ice formation in the Gulf of St. Lawrence.

Lally, Graydon D. (Graydon Douglas) January 1973 (has links)
No description available.
225

Phytoplankton Communities in Temperate Rivers

Contant, Jacinthe 23 January 2012 (has links)
The structure of phytoplankton communities was examined seasonally across five rivers with a focus on small cells and their relative importance. Picophytoplankton (0.2-2 μm), previously considered insignificant in rivers, reached densities as high as those observed in lakes and oceans (~ 10e4-10e5 cells/mL). Their relative importance was not a function of trophic state with the highest contribution to algal biomass found in the most eutrophic river. Body size distributions were analyzed from both chlorophyll-a size fractions and taxonomic enumerations; no significant effect of river or season was detected, suggesting that phytoplankton size distribution is not a useful metric of change in rivers. Unlike lake ecosystems, the rivers were uniformly dominated by small cells (< 20 μm). Taxonomic analyses of the seasonal succession did not reveal a common periodicity of particular divisions (e.g. diatoms). However, strong dominance was more typical of eutrophic rivers even though taxa richness was similar.
226

Estimating Flow, Hydraulic Geometry, and Hydrokinetic Power at Ungauged Locations in Canada

Bomhof, James 08 January 2014 (has links)
A resource assessment of the hydrokinetic potential in Canada's rivers was completed. The main objectives of the study were to (1) quantify the potential hydrokinetic energy avail- able for development both nationally and regionally, and (2) develop geospatial datasets identifying streams or areas of high hydrokinetic potential. Flow estimates at ungauged locations were found using multiple linear regression coupled with Canonical correlation analysis (MLR-CCA). Total theoretical hydro power, equivalent to total theoretical hydroki- netic power was calculated using these ow estimates and hydraulic head estimates from DEMs. It is estimated that there are 710 GW of potential power in Canadian rivers, with 97.5% con dence that there is at least 433 GW. Downstream hydraulic geometry (DHG) relations were applied to ow estimates to nd cross section velocity and power at ungauged locations. Further testing was done on DHG relations, and were found to be most accurate when characterized by soil drainage characteristics.
227

The surface waters of Winnipeg: rivers, streams, ponds and wetlands 1874-1984: the cyclical history of urban land drainage

Graham, Robert Michael W. 02 March 2012 (has links)
ABSTRACT The modern day City of Winnipeg is situated on the poorly drained floor of pro-glacial Lake Agassiz, one of the flattest regions on earth. Within the area now bounded by the Perimeter Highway sixteen major streams and at least twenty small coulees once emptied into the Àssiniboine and Red Rivers. Behind the levees of these rivers large areas of marsh existed providing detention storage of surface waters. The overflow from these wetlands fed many of the streams. The first settlers in the region mimicked the natural drainage regime by damming the waters of the streams to drive grist mills. Later agricultural settlers, occupying the uninhabited but marginally drained lands behind the levees began to drain the wetlands. During the explosive growth period of the City (1880-1910) the drainage regime was radically altered and an expensive and inadequate conduit system was substituted in it's place. Serious flooding episodes have occurred from the first alterations up to the present day. In an attempt to solve the flooding problems, overcome the expense of conduit systems and add amenity, a series of stormwater retention ponds was introduced by private developers in 1965. Functually these impoundments imitate the original hydraulic relationship between the ponds, wetlands and streams of the native landscape. Approximately on hundred years after the elimination of the natural drainage regime, Plan Winnipeg 1981 calls for the preservation of all natural watercourses in recognition of their high value for storm drainage and recreational amenity. Of the original thirty-six streams and coulees only nine exist today. All wetland storage areas have been eliminated. This practicum traces the historical progression of land drainage in the City of Winnipeg, summarizes the design criteria for future urban stormwater management, and outlines the present condition and rehabilitation of the historic water features.
228

Water-drag coefficients in the Beaufort Sea : AIDJEX 1975-76

LeBlanc, Alain, 1952- January 1981 (has links)
No description available.
229

New Dimensions in Water Conservation; An Inter-animation of Writing and Water

January 2003 (has links)
Water is a finite resource which is increasingly valued as a commodity. This thesis explores the use and appreciation of water, in the context of community response and exchange. Its focus is a community writing practice, and in particular a project entitled new dimensions in Water Conversation based in the Northern Rivers region of New South Wales. This project was a non-crisis driven investigation into a wide range of interests in water. The central proposition of the thesis is that techno-scientific and broader cultural world views on water rarely connect, and that bringing them together reveals awkward tensions between specialist and non-specialist standpoints. These disparities are shown in the group writings and outcome of the project, which bring water provision into closer perspective. A story emerges from the project and its influences. It is one of material relationships to water over testings, tastings and visits to a water treatment works. It suggests links which would not normally be anticipated, for example between a regional bulk water supplier and a group of water writers. The study combines fiction and contemplation with critical analysis and the thesis crosses disciplinary boundaries, drawing on insights from critical cultural theory and the philosophy of science. The writing is performative rather than accumulative in nature, yet is a concrete record of the interplay between water users and water specialists, in a local and global dimension which includes the Northern Rivers, Australia more generally and Varanasi in India. Using this transcultural approach, it decentres theory and locates value in the situated contexts and views of different stakeholders in water, which range from sacred values to indifference. The work calls out for a way of thinking about water that is not yet in the public discourse. Through the practical connection of the project with an Australian water instrumentality, it draws in developments in contemporary water management, and raises questions and doubts about how instrumentalist and market values have come to dominate imaginings of a global water future. At the same time it points to the importance of putting the values of the arts and humanities into practice in the increasingly inter-disciplinary environment in which the resource of water is managed and maintained.
230

Colorado River trips within the Grand Canyon National Park and Monument a socio-economic analysis.

Boster, Mark Alan. January 1972 (has links) (PDF)
Thesis (M.S. - Hydrology and Water Resources)--University of Arizona. / Includes bibliographical references.

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