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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.
131

An assessment of the social consequences of water management devices on the poor in Samora Machel, Cape Town

Ntwana, Bukiwe January 2014 (has links)
Magister Administrationis - MAdmin / This study assesses the social consequences of water management devices in poor households in Samora Machel, a poor urban area characterised by high levels of unemployment and poverty. South Africa is currently faced with an increase in the roll out of water management technologies, mainly in poor areas, allegedly to manage water demand and help poor households manage their water consumption and prevent wastage. The water management device (WMD) limits access to the free basic water (FBW) allocation and automatically cuts it off when the allocation is finished. In 2009/2010 the City of Cape Town started rolling out the devices in Samora Machel, which previously used the conventional water meter that supplied the area with unlimited water access. WMDs limit water access to 350 litres of FBW per day. People living in Samora Machel claim that 350 litres is not enough and they are experiencing problems of frequent water cuts even before the allocated litres are used up. There have also been water leaks ever since the installation of the devices. Section 27(1)(b) of the Constitution of the Republic of South Africa, Act 108 of 1996, entrenches the right of access to sufficient water. The WMDs are criticised for infringing the right of access to sufficient water supply to poor households by leaking, cutting off water supply frequently and by limiting access to FBW supply. Moreover, critics argue that the WMDs are not water-demand management mechanisms; they are cost-recovery mechanisms that are introduced under the neo-liberal policies introduced by the post-apartheid government in 1994. This criticism is based on the fact that the WMDs are implemented in poor areas only, where water is needed more for basic survival, rather than in high-income areas, where water is mostly used for luxury purposes.
132

Water sensitive urban design as a transformative approach to urban water management in Cape Town: A case study of the proposed River Club development

Gluckman, Lloyd January 2017 (has links)
The author examines effective urban water management as a means to promote sustainable development and achieve water sensitive cities. A qualitative method is utilised in the collection of data through document studies, desktop analysis and a literature review. A review of the current national and local water policies and approaches within South Africa, and more specifically Cape Town, indicated the need for a coordinated, systems based and holistic approach to urban water management. Water Sensitive Urban Design (WSUD) is considered as an alternative approach to urban water management in Cape Town to build resilience among local communities against the threat of drought and flood events, and promote sustainable development in moving toward a water sensitive city. A model for implementing WSUD in the context of limited resources and capacity within local municipal departments is considered. Incorporating the principles of WSUD within spatial planning initiatives to implement this approach and catalyse a systemic transition in urban water management is considered and assessed in a case study of the proposed development of the River Club. The case study considers a bottom-up approach to transforming urban water management and the capacity of WSUD, when implemented through spatial planning, to simultaneously address multiple objectives including those of sustainable development and those contained within national and local policies. The benefits of a WSUD approach for all are considered. Many if these benefits are as a result of reduced pressures on municipal infrastructure and increased water resources accrued as a product of the proposed implementation model. The implementation model proposed creates conditions in which municipal resources and investment can be redirected to promote equitable water resource and service provision distribution throughout the city. The model is proposed to effect a transformation in water policy, institutional structures and water resource management to reflect the principles of WSUD in a manner which is cognisant of the various limitations inherent to the City.
133

The utilisation of spatial planning in improving urban water culture: a case study of Oranjezicht, Cape Town

Petersen, Gadija Assaa-Imah January 2018 (has links)
Nothing can exist, live, survive or thrive without water. Water is the basis of life for all living organisms and the centre of life for all societies. The global attitude around water has become territorial as it encompasses an intricate link to the development of nations. Centralising main water supplies beyond urban boundaries may have improved the utilisation of water but has also resulted in the separation of society and water. Water is what gave rise to the city of Cape Town, as there was an abundance of rivers and springs located on and around Table Mountain. This water was first used by the Khoi people and became the reason for colonial settlers residing in the Cape. The City is currently experiencing the worst water crisis in over a century due to increased temperatures and decreased rainfall. Amid the water crisis there appears to be underused, freshwater below Cape Town's CBD, flowing to the Atlantic Ocean via the stormwater reticulation system. This water originates from Table Mountain's rivers, streams and, to an extent, springs. Naturally, the drought has sparked widespread concern for, and attention given to, water and its sustainable usage. This dissertation explores the ways in which the City's water, environmental and spatial planning policies could spark a new and improved water-culture within Cape Town to ensure sustainable, long-term water availability. This is done through investigating the potential of Oranjezicht in becoming a catalytic area for water sustainability due to the locations of the Field of Springs and the Platteklip Stream. This dissertation proposes using water sensitive urban design as well as integrated, collaborative partnerships and management mechanisms to encourage an improved urban water culture.
134

Participation of women in irrigation and water management in Sindh on-farm water management and irrigation system rehabilitation project.

Soomro, Abdullah January 2013 (has links)
Gender is a behavioural norm attributed to men and women in a given social system. Gender defines the role of women socially and in day to day life, especially when it comes to the access to the safe water. However, their participation is very little. Water projects by nature are gender sensitive and thus should have gender equality, starting from planning and decision making level to execution. In agricultural sector we need more water than other sectors. Men have been predominant decision makers for water management in agriculture and farm work while women have been thought to be responsible for household chores. However, in reality, women have always been prime participants in the agricultural production system. The aim of this thesis was to assess the participation of women in the “Sindh On-Farm Water Management Project”. In this regard a study was carried out in the project area using written questionnaires and face to face interviews that were even recorded using video. According to the results obtained a handful of women who own lands who will be affected by this project. They are aware of the project but reluctant to participate. Some others who work as farm laborers are unaware of the project but would be interested in participation. Finally, women working as professionals, social mobilizers and consultants have diverse views about their own work, working conditions and participation of women concerned with land and farming. The thesis concludes that the Sindh project was a good exercise to involve women and give them confidence to take part in decision making. It is a good start but lot more need to be done to actually give women their due right especially in rural areas of developing countries.
135

Skånskt Vatten 2120

Lysholm, Rebecka January 2018 (has links)
Uppsatsen berör den komplexa frågan om hur vatten värderas i landskapets ekosystem förhållande som en resurs till människan. Uppsatsen syftar till att undersöka vilka faktorer som är betydande för att ändra attityden till sötvatten och vilka tekniska lösningar, med fokus på avsaltningsanläggningar, som kan vara svaret till framtidens sötvattenproblematik för kustnära städer i Skåne. Genom kvantitativa observationer skapas en giltig teori av ”Skånsk vattenhantering 2120” byggd på generaliseringar av empirin. Därav är uppsatsen av en kvalitativ, induktiv, forskningskaraktär.Genom användningen av scenariometodik presenteras de hot och risker det konventionella vattensystemet kommer utgör för de kustnära städernas ekosystemen och samhällen i Skåne till följd av klimatförändringarna. Vattensystemets karaktär vilket förhindrar vattnet att följa dess naturliga kretslopp i samband med dess otillräckliga kapacitet medför att varken den ekologiska eller sociala dimensionen av hållbar utveckling uppnås. Dem identifierade trenderna för scenariot var: klimatförändringar, befolkning, landskap och vattenanvändning. Den mest betydande trenden visades vara vattenanvändning eftersom den rymmer de mänskliga faktorerna så som konsumtion, attityder och politik. / This paper touch the the complex issue regarding the value of water as a recourse for the ecosystem or for the human. The purpose is to analyse which factors that are of importance for changing the attitude towards freshwater, and what technical solutions, focusing on desalination plants, that can solve the future fresh water issue in the costal cities of Scania, Sweden. Through quantitative observations, a valid theory of "Scania Water Management 2120" is created based on generalizations of empire. Hence the essay holds a qualitative, inductive, research character.By the use of scenario methodology, the climate change effects on the costal cities in Scania will present the threats and risks the conventional water system pose, both for the ecosystem and the society. The systems characteristics which prevent the water from following its natural cycle in combination with its limited capacity entails that neither the ecological nor the social dimension of a sustainable developments is fulfilled. The identified trends for the scenario was: Climate change, Population, the Landscape and Water use. The trend of highest importance was shown to be Water use since it holds the human factors, such as consumption, attitudes and politics.
136

Impact on Rural Incomes of Improved Water Management Practices in Milagro County, Ecuador

Lloyd, Phillip H. 01 May 1972 (has links)
Farm budgets based on survey data a r e used to calculate the net revenue for average irrigated and unirrigated farms for four tenure classes on the Milagro irrigation project, Ecuador. Differences in net revenues between irrigated and unirrigated farms within each tenure class are assumed to be the return to investment in irrigation capital, assuming homogeneity of all other production factors. The internal rate of return is calculated on investment in irrigation capital assuming returns to such an investment are the difference in net revenues between irrigated and unirrigated farms. Investment in such capital is found to be highly profitable assuming the opportunity cost of capital is 12 per cent. However, small size farms (minifundios) are relatively more profitable than larger farms. Also, the pure economic profit (rent) accruing to each hectar of land is determined. This is done by finding the water tariff that causes the internal rate of return to fall to 12 per cent and subtracting the current water tariff per hectar (S/. 200) from the maximum tariff. The difference is rent per hectar, which is greater for small farms than larger ones. However, when total land area by tenure class is considered, larger farms capture the greatest share of the economic rent from the project.
137

Influence of Phosphorus and Water Management on Mycorrhiza and Rhizobia in Symiosis With Legumes

Ianson, David C. 01 May 1982 (has links)
Mycorrhizal associations are very important to plant growth. This is mainly due to the hyphal stands that are able to utilize concentrations of nutrients that would normally be considered unavailable for plant growth, especially phosphorus. These associations are of great importance in soils that have been disturbed by mineral extraction and are consequently low in available nutrients. The ability of mycorrhizal fungi to form associations on disturbed sites may be dictated by a number of factors: moisture, soil pH, soil fertility (including heavy metal ions), salinity, and plant response. Two factorial experiments were conducted with the legume Hedysarum boreale cv utahensis and the mycorrhizal fungus Glomus mosseae. The first to observe the effects of three factors: fungi level (mycorrhizal or non-mycorrhizal), type of phosphate (P) (monocalcium or superphosphate), and irrigation intervals (2, 4, or 8 day) on root and shoot dry weights. The second experiment was conducted to observe the effects of three factors: fungi level, type of P and level of P on root and shoot dry weights, root and shoot P concentration, nodulation and nitrogen fixation. In the first experiment, the combination of fungi level and type of P had a significant effect on root /shoot ratio (weight ). In the second experiment, the interaction of fungi level, type of P and level of P had a significant effect on nodulation. The interaction of P type and P level had a significant effect on the amount of phosphorus found in plant roots and shoots. The factor, fungi level, had a significant effect on shoot dry weight, with mycorrhizal plant's shoots having a significantly greater dry weight than non-mycorrhizal shoots. Mycorrhizal infection may have been greatly reduced by the adverse soil conditions found in the mine spoil (i.e. low pH, high salinity , and high heavy metal concentration). What infection did occur may have been great enough to produce changes in the shoot dry weight, but not great enough to significantly enhance plant P uptake. The reintroduction of mycorrhizae into disturbed areas for reclamation purposes may be important for rapid establishment of plant cover and to speed up succession. Before mycorrhizae can be reestablished in a disturbed area, many potential stress factors need to be addressed and, if possible, overcome.
138

Methodology to Predict Daily Groundwater Levels by the Implementation of Machine Learning and Crop Models

Gutierrez, Sandra Milena Guzman 12 August 2016 (has links)
The continuous decline of groundwater levels caused by variations in climatic conditions and crop water demands is an increased concern for the agricultural community. It is necessary to understand the factors that control these changes in groundwater levels so that we can better address declines and develop improved conservation practices that will lead to a more sustainable use of water. In this study, two machine learning techniques namely support vector regression (SVR) and the nonlinear autoregressive with exogenous inputs (NARX) neural network were implemented to predict daily groundwater levels in a well located in the Mississippi Delta Region (MDR). Results of the NARX model indicate that a Bayesian regularization algorithm with two hidden nodes and 100 time delays was the best architecture to forecast groundwater levels. In another study, the SVR and the NARX model were compared for the prediction of groundwater withdrawal and recharge periods separately. Results from this study showed that input data classified by seasons lead to incremental improvements in the model accuracy, and that the SVR was the most efficient machine learning model with a Mean Squared Error (MSE) of 0.00123 m for the withdrawal season. Analysis of input variables such as previous daily groundwater levels (Gw), precipitation (Pr), and evapotranspiration (ET) showed that the combination of Gw+Pr provides the optimal set for groundwater prediction and that ET degraded the modeling performance, especially during recharge seasons. Finally, the CROPGRO-Soybean crop model was used to simulate the impacts of different volumes of irrigation on the crop height and yield, and to generate the daily irrigation requirements for soybean crops in the MDR. Four irrigation threshold scenarios (20%, 40%, 50% and 60%) were obtained from the CROGRO-Soybean model and used as inputs in the SVR to evaluate the predicted response of daily groundwater levels to different irrigation demands. This study demonstrated that conservative irrigation management, by selecting a low irrigation threshold, can provide good yields comparable to what is produced by a high volume irrigation management practice. Thus, lower irrigation volumes can have a big impact on decreasing the amount of groundwater withdrawals, while still maintaining comparable yields.
139

Modeling And Analysis Of Rainwater Harvesting Systems Under Different Climates

El Ganzouri, Ahmed 11 1900 (has links)
There is a strong interest in rainwater harvesting (RWH) solutions as the global demand for water increases and water sources face contamination and depletion. Despite the extensive research conducted on the impact of RWH on watersheds, there is significant research to be completed to determine the relationship between the collection tank volume, roof size, and water demand satisfied by the RWH system. This thesis aims to further the understanding of the behaviour of RWH systems through a quantitative assessment of the water provided by these systems. Calculating the reliability of RWH systems in various Canadian regions allows for an evaluation of the capacity of RWH in meeting various residential water needs in Canada’s diverse climates. The results are obtained through hourly continuous simulation to provide the most accurate results and are presented in a user-friendly format through simple equations and graphs. RWH modeling through analytical equations do not require long-term historical data and are easier to use than conducting computer-aided continuous simulations. A better understating of the analytical equations’ application is developed through a comparison between the analytical and continuous simulations methods. The comparison is held for different regions within Canada, and the analysis confirms a lack of accuracy for the analytical method in some climatic conditions. Daily continuous simulations conduced for Ugandan and Canadian regions provide a perspective on the feasibility of RWH systems to meet the human right to drinking water in the two countries. A comparison of the reliability of RWH tanks in Ugandan and Canadian regions is conducted to provide insight into the impact of rainfall patterns on the reliability of RWH systems. The evaluation of RWH performance in the RRM context in Canada and Uganda is aimed to address the lack of adequate water sources in rural, remote, and otherwise marginalized (RRM) communities globally. Examining the most accurate and appropriate modeling tools and assessing the actual yield of RWH systems provides information critical to water-sensitive communities and provides a foundation for future research to further explore the most effective application of RWH in urban and water-sensitive communities. / Thesis / Master of Applied Science (MASc)
140

Effects of Localized Irrigation and Fertilizer on Woody Plant Establishment in Degraded Semi-Arid Environments

Lund, Holley M. 09 August 2022 (has links)
Semi-arid native plant communities worldwide are often disturbed either intentionally or incidentally by human activity. In order to restore ecological function after human activities cease, native plant communities need to be restored. Woody plants are important to ecological function for many reasons including reducing erosion and providing food and shelter for wildlife. Unfortunately, woody plant establishment in these areas has proven to be challenging. Direct seeding efforts can be hindered by poor germination and low seedling emergence. To overcome this, seedling transplants are often used in harsh sites. However, transplanted woody seedlings often experience high mortality during the first year, predominantly as a result of stress during the summer. The Waterboxx® device is a tool that collects precipitation and condensates into a polypropylene reservoir, slowly releasing the water into the soil next to the seedling. Low soil fertility can also limit seedling establishment. In two studies, we evaluated the use of Waterboxx® devices with one wick or two wicks, and/or fertilizer as tools for establishing seedlings on a reclaimed waste rock pile. We also looked at the effects of either placing the Waterboxx® on the soil surface or burying the Waterboxx® partway into the ground. The first study focused on different species in the Waterboxx®. Species planted in the first study were Atriplex canescens, Cercocarpus ledifolius, Pinus edulis, Purshia tridentata and Rhus glabra. The second study focused on number of wicks, addition of fertilizer, and method of Waterboxx® instillation. This study was conducted with only one species: C. ledifolius. In both studies, the Waterboxx® device improved survival and vigor. In the second study, fertilizer was detrimental to seedling survival, and Waterboxx® devices installed on top of the soil had no difference in survival or vigor compared to the control, but partially buried devices were better than the control and Waterboxx® devices with two wicks had the best C. ledifolius seedling survival. Based on the results obtained, Waterboxx® devices were a viable method for most of these species in improving their establishment on mine land overburden sites in the semi-arid mountain west and additional research is merited for other areas of the world.

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