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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.
161

The Impact of Environmental Change and Water Conservation on Dryland Groundwater Resources in Northern Egypt: Modeling Aquifer Response Using Sparse Data

Switzman, Harris R. 10 1900 (has links)
<p>Please contact the author with any questions. A compressed tar.b2z file is attached with the groundwater model input files.</p> / <p>Wadi El Naturn, located in the Western Desert in northern Egypt, has been subject to significant groundwater degradation since the 1990s, attributed primarily to agricultural development. Information required to diagnose the drivers of groundwater degradation and assess management options in dryland environments like Wadi El Natrun is however, frequently sparse. This research presents an approach for modeling the impacts of dryland environmental change on groundwater in the context of sparse data. A focus is placed on understanding the potential impacts of conservation strategies in the context of climate change. Water use, hydrostratigraphic and groundwater flow data were collected from literature, monitoring records, satellite imagery and a survey of local landholders. MODFLOW-NWT was used to model the multi-layer aquifer system, and algorithms were developed in R to create realizations of groundwater recharge, and well-pumping at a monthly time-step from 1957 to 2011. The model was deemed to be reasonably capable of capturing the cumulative impact of environmental change over this historical period. A risk assessment approach was then used to assess the impact of climate change and conservation-focused management scenarios on groundwater locally over a 50-year future planning horizon. The optimization of irrigation systems and increased cultivation of drought/salt tolerant crops have the potential to significantly reduce the risk of groundwater depletion compared to an across-the-board 20% water use reduction scenario. The influence of groundwater pumping also outweighed that of climate change, and the most vulnerable water users/ecosystem were found to be the most exposed to groundwater degradation.</p> / Master of Applied Science (MASc)
162

Water Supply Planning for Landscape Irrigation in Virginia

Tucker, Adrienne Janel LaBranche 10 June 2009 (has links)
A water supply plan approach was used to investigate irrigation application on landscaped areas in Virginia with a focus on turfgrass. The economically-important turfgrass industry in Virginia should be proactive in conserving drinking water supplies to meet human consumption needs, especially in drought times. This thesis investigates current irrigation water supplies, water supply sustainability, and alternative water sources to meet irrigation demands and offers an insight on how potable water is unnecessarily consumed for non-potable irrigation needs. A Virginia evapotranspiration website was developed to offer a scientifically based source for efficient irrigation scheduling. The website was developed using a collaborative and user-centered design method, which included potential users in the process. The final website is hosted on the Virginia Tech website at http://www.turf.cses.vt.edu/Ervin/et_display.html and utilizes data from weather stations throughout the state. Evapotranspiration-based irrigation was tested at three case study sites in Blacksburg, Williamsburg and Norfolk, Virginia to assess potential water conservation. In Williamsburg, a 55% water savings was reported with evapotranspiration-based irrigation. In Blacksburg, slightly more water was applied on research greens irrigated based on evapotranspiration demand. Significantly less water was applied in Norfolk, compared to the evapotranspirationbased irrigated plots. The study also uncovered increased confidence to alter irrigation systems and the need to conduct irrigation audits when irrigating based on evapotranspiration. Evapotranspiration-based irrigation, reclaimed water and harvested rainwater were investigated to determine feasibility for meeting irrigation demands, while reducing potable water consumption at four case study sites in Blacksburg, Fairfax, Williamsburg and Norfolk, Virginia. Due to the limited collection potential at the Blacksburg site, reclaimed water and harvested rainwater was not feasible. However, the on-site weatherstation could offer a unique opportunity to calculate evapotranspiration. In Fairfax, all three alternative water sources could be integrated to supply enough water to irrigate a soccer field and adjacent athletic fields and save an estimated $7,000 per season in potable water costs. Harvested rainwater at the Williamsburg site could supplement the irrigation pond and reduce reliance on groundwater. In Norfolk, reclaimed water use is economically feasible, but rainwater harvesting could meet the irrigation needs, while evapotranspiration-based irrigation is too labor intensive for homeowners. / Ph. D.
163

Segmentation of the market for labeled ornamental plants by environmental preferences: A latent class analysis

D'Alessio, Nicole Marie 09 July 2015 (has links)
Labeling is a product differentiation mechanism which has increased in prevalence across many markets. This study investigated the potential for a labeling program applied in ornamental plant sales, given key ongoing issues affecting ornamental plant producers: irrigation water use and plant disease. Our research investigated how to better understand the market for plants certified as disease free and/or produced using water conservation techniques through segmenting the market by consumers' environmental preferences. Latent class analysis was conducted using choice modeling survey results and respondent scores on the New Environmental Paradigm scale. The results show that when accounting for environmental preferences, consumers can be grouped into two market segments. Relative to each other, these segments are considered: price sensitive and attribute sensitive. Our research also investigated market segments' preferences for multiple certifying authorities. The results strongly suggest that consumers of either segment do not have a preference for any particular certifying authority. / Master of Science
164

The Influence of Conservation Programs on Residential Water Demand: Synthesis and Analysis for Shared Vision Planning in the Rappahannock River Basin

Cartwright, Lauren Ashley 09 January 2003 (has links)
The Rappahannock River Basin Commission is undergoing a collaborative water supply planning process for Virginia's Rappahannock River Basin. Participants in the planning process have indicated an interest in technical information about the possible impact conservation programs may have on reducing residential water demand. The potential influence of conservation programs is identified through a literature synthesis and a statistical analysis of residential water demand for a locality within the basin (Stafford County). In the literature synthesis, conservation programs are classified as voluntary or mandatory. Voluntary programs utilize financial incentives (such as water pricing and rebates) or educational incentives (such as radio ads and bill inserts) to encourage conservation, and mandatory programs utilize regulatory incentives (such as plumbing standards and bans on outdoor water use). The water demand statistical model was estimated to more specifically identify how Stafford residential water customers respond to water pricing/rate structure changes (financial incentives), imposition of federal regulations on plumbing standards (regulatory incentives), and a voluntary conservation program utilizing educational incentives. The results indicate that while many studies have found residential customers are responsive to price changes, Stafford residential water users have not significantly changed their water demand in response to price/rate structure changes. Previous literature also suggests federal plumbing standards potentially have a significant impact on water demand. The influence of new plumbing standards in the Stafford demand model was inconclusive and warrants further analysis. Consistent with the literature, voluntary conservation programs utilizing educational incentives alone did not substantially alter residential water demand in Stafford County. / Master of Science
165

The development of an environmental education programme for water conservation in the Steelpoort area

Mathipa, Katishi Silas 25 August 2009 (has links)
The purpose of this study was to determine what activities and practices prejudice water conservation in the Steelpoort area. Using this information, context specific environmental education programmes were designed for various sectors of the community. A qualitative research approach was used. Respondents who provided information through interviews and questionnaires included school principals and educators, non-teaching staff members, learners and adult community members. The theory developed from the literature review facilitated the development of qualitative research for the study. The research identified certain activities and practices that contribute to the unsustainable use of water in the area. The respondents suggested that consumers generally need to acquire knowledge and skills that will enable them to effectively conserve and utilise water. Specific programmes intended to meet the needs of the various categories of consumers that will facilitate water conservation and its sustainable use were designed as an outcome and recommendation of the research. / Educational Studies / M.Ed. (Environmental Education)
166

A proactive water supply shortage response plan focusing on the Green Industry in the Rand Water supply area

Hoy, Leslie Higham 01 1900 (has links)
Water is a symbol of life. It affects all organisms on earth and its importance is emphasised in times of drought. The human population growth places more demands on our natural resources. As pressures on the available water increases, more measures are required to utilise water sustainably. South Africa is classified as a water stressed country with less than 1700 cubic meters of water available per person per year. Rand Water supplies water to approximately 11 million people in Gauteng. During times of drought, restrictions imposed are aimed mainly at the broader Green Industry. This research investigated international strategies, existing restrictions in Gauteng, and undertook a survey within the Green Industry to determine the most appropriate response. This research proposes a new water supply shortage response plan for Rand Water in Gauteng with a total of four levels of restrictions implemented at different stages of water stress in the system. / Environmental Sciences / M. Sc. (Environmental Management)
167

Modelling amenity landscape plant water use in South Africa

Hoy, Leslie Higham 12 1900 (has links)
South Africa is classified as a semi-arid environment with limited natural water sources. Amenity landscapes provide broad ranging benefits for society. Amenity landscapes account for between 31% - 50% of water supplied for domestic and urban use. To reduce water use and water conservation in amenity landscapes, strategies, regulations and interventions are required. Every landscape is a unique complex system with a large number of variables that differ from each other. The variability can be summarized into management/design, irrigation, climatological, edaphic and plant related aspects. Several amenity landscape water use models have been developed around the world and two in South Africa. This study developed a comprehensive South African hydrozone based plant database and an Amenity Landscape Water Use Model South Africa (ALWUMSA). This will improve hydrozoning of amaneity landscapes and ultimately also improve water conserbvation for these sites. It allows users/owners to determine water use requirements through an extensive data gathering, from aspects such as design, management, microclimate, environmental, edaphic, irrigation and plant related factors. Comparisons of results from ALWUMSA to three test sites, selected existing models and a range of scenarios produced results demonstrating that ALWUMSA consistently projected lower water requirements. The model also allows for site aspects to be changed thus encouraging end users to implement specific water saving intiatives with the amenity landscape to reduce water use. These savings will be translated into both water-use savings as well as financial savings for users of the amenity landscape water use model. / Environmental Sciences / Ph. D. (Environmental Science)
168

The development of an environmental education programme for water conservation in the Steelpoort area

Mathipa, Katishi Silas 25 August 2009 (has links)
The purpose of this study was to determine what activities and practices prejudice water conservation in the Steelpoort area. Using this information, context specific environmental education programmes were designed for various sectors of the community. A qualitative research approach was used. Respondents who provided information through interviews and questionnaires included school principals and educators, non-teaching staff members, learners and adult community members. The theory developed from the literature review facilitated the development of qualitative research for the study. The research identified certain activities and practices that contribute to the unsustainable use of water in the area. The respondents suggested that consumers generally need to acquire knowledge and skills that will enable them to effectively conserve and utilise water. Specific programmes intended to meet the needs of the various categories of consumers that will facilitate water conservation and its sustainable use were designed as an outcome and recommendation of the research. / Educational Studies / M.Ed. (Environmental Education)
169

A proactive water supply shortage response plan focusing on the Green Industry in the Rand Water supply area

Hoy, Leslie Higham 01 1900 (has links)
Water is a symbol of life. It affects all organisms on earth and its importance is emphasised in times of drought. The human population growth places more demands on our natural resources. As pressures on the available water increases, more measures are required to utilise water sustainably. South Africa is classified as a water stressed country with less than 1700 cubic meters of water available per person per year. Rand Water supplies water to approximately 11 million people in Gauteng. During times of drought, restrictions imposed are aimed mainly at the broader Green Industry. This research investigated international strategies, existing restrictions in Gauteng, and undertook a survey within the Green Industry to determine the most appropriate response. This research proposes a new water supply shortage response plan for Rand Water in Gauteng with a total of four levels of restrictions implemented at different stages of water stress in the system. / Environmental Sciences / M. Sc. (Environmental Management)
170

A recursive programming analysis of water conservation in Arizona agriculture : a study of the Phoenix active management area

Lierman, Wally Kent. January 1983 (has links)
Arizona agriculture faces many changes in the near future. One of the most imminent changes will come from the enactment of the 1980 Arizona Groundwater Management Act. The 1980 AGWMA is designed ultimately to curtail the use of groundwater in Arizona. Agriculture will be affected since this sector used approximately 87 percent of all water in the State in 1980. This study reports on the possible effects that a proposed pump tax and water duty policy would have on agriculture within the Phoenix Active Management Area. The PAMA is one of four such areas in the State that have been identified as needing groundwater use management. The results of this study indicate that the proposed water duty is more effective in curbing groundwater use than the proposed pump tax. Investment in more water application efficient irrigation technologies is also important in this study. However, substantial amounts of capital investment funds will be needed to begin this investment.

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