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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.
1

Advancing cumulative effects assessment methodology for river systems

Seitz, Nicole Elyse 14 April 2011
Increased land use intensity has adversely affected aquatic ecosystems within Canada. Activities that occur over the landscape are individually minor but collectively significant when added to other past, present, and reasonably foreseeable future actions, and are defined as cumulative effects. Existing approaches to cumulative effects assessment for river systems within Canada are ineffective. This thesis aims to improve the practice of cumulative effects assessment by evaluating current methodology for linking landscape change and river response over a large spatiotemporal scale. As part of this goal, I offer a framework for better incorporating science into current practices for cumulative effects assessment. The framework addresses the challenges involved in cumulative effects assessment, such as defining appropriate spatial and temporal scale, complex ecological and hydrologic pathways, predictive analysis, and monitoring. I then test the framework over a large spatiotemporal scale using a case study of the lower reaches of the Athabasca River Basin, Alberta. Three objectives are addressed: 1) changes in land use and land cover in the lower ARB for several census dates (1981, 1986, 1991, 1996, 2001) between 1976 (historic) and 2006 (current day) are identified; 2) linkages between landscape change and river water quality and quantity response are evaluated; and 3) results of the different methods used to link landscape stressors with stream responses are compared. Results show that the landscape has changed dramatically between 1976 and 2006, documented by increases in forest harvesting, oil sands developments, and agricultural intensity. Secondly, results suggest that linear regression tests combined with regression trees are useful for capturing the strongest associations between landscape stressors and river response variables. For instance, water abstraction and agricultural activities have a significant impact on solute concentrations. This suggests that water abstraction and agriculture are important indicators to consider when conducting a watershed cumulative effect assessment on a similar spatiotemporal scale. The thesis has strong implications for the need for improved water quality and quantity monitoring of Canada‟s rivers. The research provides a means of identifying appropriate tools for improved watershed cumulative effects assessment for scientists and land managers involved in the environmental impact assessment process and protection of Canada‟s watersheds.
2

Advancing cumulative effects assessment methodology for river systems

Seitz, Nicole Elyse 14 April 2011 (has links)
Increased land use intensity has adversely affected aquatic ecosystems within Canada. Activities that occur over the landscape are individually minor but collectively significant when added to other past, present, and reasonably foreseeable future actions, and are defined as cumulative effects. Existing approaches to cumulative effects assessment for river systems within Canada are ineffective. This thesis aims to improve the practice of cumulative effects assessment by evaluating current methodology for linking landscape change and river response over a large spatiotemporal scale. As part of this goal, I offer a framework for better incorporating science into current practices for cumulative effects assessment. The framework addresses the challenges involved in cumulative effects assessment, such as defining appropriate spatial and temporal scale, complex ecological and hydrologic pathways, predictive analysis, and monitoring. I then test the framework over a large spatiotemporal scale using a case study of the lower reaches of the Athabasca River Basin, Alberta. Three objectives are addressed: 1) changes in land use and land cover in the lower ARB for several census dates (1981, 1986, 1991, 1996, 2001) between 1976 (historic) and 2006 (current day) are identified; 2) linkages between landscape change and river water quality and quantity response are evaluated; and 3) results of the different methods used to link landscape stressors with stream responses are compared. Results show that the landscape has changed dramatically between 1976 and 2006, documented by increases in forest harvesting, oil sands developments, and agricultural intensity. Secondly, results suggest that linear regression tests combined with regression trees are useful for capturing the strongest associations between landscape stressors and river response variables. For instance, water abstraction and agricultural activities have a significant impact on solute concentrations. This suggests that water abstraction and agriculture are important indicators to consider when conducting a watershed cumulative effect assessment on a similar spatiotemporal scale. The thesis has strong implications for the need for improved water quality and quantity monitoring of Canada‟s rivers. The research provides a means of identifying appropriate tools for improved watershed cumulative effects assessment for scientists and land managers involved in the environmental impact assessment process and protection of Canada‟s watersheds.
3

Factors Affecting Sediment Oxygen Demand of the Athabasca River Sediment under Ice Cover

Sharma, Kusumakar Unknown Date
No description available.
4

Změny srážko-odtokového režimu v povodí řeky Athabaska / Changes of rainfall-runoff regime in the Athabasca River basin

Fraindová, Kateřina January 2014 (has links)
Athabasca River Basin is located in an area which is affected by many factors. During the last century, the global warming manifests here, resulting primarily into increasing temperatures and glaciers melting in the headwaters area. Much of the middle reaches watershed is used for agriculture, for irrigation of which water from the Athabasca River is pumped. In recent years, controversial development of bituminous sands mining is carried out in the basin. Although it represents a real energy source, the mining requires large amounts of water, which is largely drawn from the Athabasca River. The work therefore analyzes the runoff change in the upper, middle and lower reaches during the last forty years. Along with the time series air temperature changes and precipitation totals, which can also explain runoff changes, are analyzed. Powered by TCPDF (www.tcpdf.org)
5

Effects of climate variability and change on surface water storage within the hydroclimatic regime of the Athabasca River, Alberta, Canada

Walker, Gillian Sarah 02 May 2016 (has links)
Warmer air temperatures projected for the mid-21st century under climate change are expected to translate to increased evaporation and a re-distribution of precipitation around the world, including in the mid-latitude, continental Athabasca River region in northern Alberta, Canada. This study examines how these projected changes will affect the water balance of various lake sizes. A thermodynamic lake model, MyLake, is used to determine evaporation over three theoretical lake basins – a shallow lake, representative of perched basins in the Peace-Athabasca Delta near Fort Chipewyan; an intermediate-depth lake representative of industrial water storage near Fort McMurray; and a deep lake representative of future off-stream storage of water by industry, also near Fort McMurray. Bias-corrected climate data from an ensemble of Regional Climate Models are incorporated in MyLake, and the water balance is completed by calculating the change in storage as the difference between precipitation and evaporation. Results indicate that evaporation and precipitation are projected to increase in the future by similar magnitudes, thus not significantly changing the long-term water balance of the lakes. However, intra-annual precipitation and evaporation patterns are projected to shift within the year, changing seasonal water level cycles, and the magnitudes and frequencies of extreme 1-, 3- and 5-day weather events are projected to increase. These results demonstrate that future climate change adaptation and mitigation strategies should take into account increases in intra-annual variability and extreme events on water levels of lakes in mid-latitude, interior hydroclimatic regimes. / Graduate / 0368 / walkerg@uvic.ca
6

2-D modeling of freeze-up processes on the Athabasca River downstream of Fort McMurray, Alberta

Wojtowicz, Agata Unknown Date
No description available.
7

2-D modeling of freeze-up processes on the Athabasca River downstream of Fort McMurray, Alberta

Wojtowicz, Agata 06 1900 (has links)
This study is part of a three year project aimed to assess the effects of industrial water withdrawals on the ice regime of the Athabasca River. A 2-D numerical model was used to provide quantitative data for this effort. Freeze-up monitoring was carried out over two years along 80-km of the river from Fort McMurray to Bitumount. Summer bathymetric and winter ice surveys were conducted along with discharge measurements on a 5-km long detailed study reach that exhibited the full range of ice cover initiation processes. The data collected was used to build a CRISSP2D river ice process model for the simulation of freeze-up processes. An extensive parametric assessment was carried out to evaluate the capabilities of the model. Although it was not possible to simulate bridging, the simulated border ice agreed very well with field observations. Limitations of the model are addressed and future research recommendations are included. / Water Resources Engineering
8

Analysis of the cost effectiveness of alternative policies and technologies to manage water extractions by the oil sands sector along the lower Athabasca River

Mannix, Amy Elinor Unknown Date
No description available.
9

Analysis of the cost effectiveness of alternative policies and technologies to manage water extractions by the oil sands sector along the lower Athabasca River

Mannix, Amy Elinor 11 1900 (has links)
The Lower Athabasca Water Management Framework limits water extractions by the oil sands industry near Fort McMurray, Alberta. To increase water-use efficiency and minimise the cost of water restrictions, several policy and technology options were developed and assessed using quantitative and qualitative methods. Selected options were the policies of water trade and pricing with refund, and the technologies of storage, and consolidated tailings and increased recycling. Options were designed based on year 2020 demand and assessed relative to prior allocation. Using linear programming and static optimisation, it is shown that an off-stream storage sized to avoid water restrictions, in combination with efficient water allocation (e.g. water trade), is most cost-effective, although provides no ongoing incentive to increase water-use efficiency. Only the policy options provide equal incentives across firms to increase efficiency. To achieve both objectives of increased water-use efficiency and minimised costs, a combined policy and technology approach is recommended. / Agricultural and Resource Economics
10

Udržitelný rozvoj v Kanadě ve vztahu k těžbě ropných písků / Sustainable Development in Canada in Relation to Oil Sands Developments

Podhola, Adam January 2013 (has links)
The aim of this thesis is to evaluate to what extent Canada and Alberta have been fulfilling the principles of sustainable development as they have adopted in the 1990s from the essential U.N. documents - the Brundtland Report and the Rio Declaration- and to what extent both governments failed in providing and enforcing efficient environmental law protection as it is the basic premise for achieving sustainability. I assessed this level of sustainability in Canada and Alberta on the basis of a stronger and weaker sustainability theoretical framework. Author's presumption was that Canada, as it defined sustainable development in its legislation, acted according to stronger sustainability, which emphasizes stronger protective environmental measures. Given a very large scope of environmental impacts of oil extraction on different ecosystems, the sector of water resources was selected to serve as a case study to compare and analyze government and alternative reports assessing the sustainability of water management. Thus, the author follows how the oil industry in Alberta affects the water resources and how both governments of Canada and Alberta provide environmental protection to the water resources. In this respect the author illustrates how the government is reluctant towards the implementation of...

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