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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.
11

Proposed methodology of allocation of water in periods water shortage for vale do Rio Curu-Cearà / Proposta metodolÃgica de alocaÃÃo de Ãgua em perÃodos de escassez hÃdrica para o vale do Rio Curu - CearÃ

MarcÃlio Caetano de Oliveira 27 November 2013 (has links)
A escolha acertada de um modelo de alocaÃÃo de Ãgua em perÃodos crÃticos ameniza o sofrimento causado pela ausÃncia de um bem tÃo precioso. Apesar da infraestrutura hÃdrica existente, o estado do Cearà vem sofrendo com os problemas causados pela estiagem. A metodologia de alocaÃÃo de Ãgua, sobretudo em perÃodos de escassez, precisa ser formatada e discutida com os agentes envolvidos nesse processo. Esta pesquisa tem como objetivo apresentar uma proposta de estratÃgia para alocaÃÃo de Ãgua, em perÃodo de escassez, para o Vale do Rio Curu, CearÃ, construÃda a partir da junÃÃo de dois mecanismos de alocaÃÃo: a formaÃÃo de consenso entre usuÃrios e instrumentos econÃmicos. à demonstrado, para isso, que o uso da Ãgua no Vale do Curu à predominante na atividade de irrigaÃÃo. Dessa forma, a estratÃgia proposta à composta por um sistema de prioridades de uso de Ãgua intrassetorial para irrigaÃÃo, com base na cobranÃa pelo uso da Ãgua variando em funÃÃo da garantia de longo prazo. Os recursos arrecadados com essa cobranÃa serÃo utilizados para pagamento de seguro e compensaÃÃo financeira, em anos secos, aos usuÃrios com garantia menores. A metodologia de alocaÃÃo proposta alcanÃou resultados satisfatÃrios quanto aos critÃrios de eficiÃncia econÃmica, legitimidade e sustentabilidade polÃtica, equidade, sustentabilidade financeira e capacidade de adaptaÃÃo. Para sua efetiva implantaÃÃo, foram sugeridas as medidas necessÃrias de controle, monitoramento e fiscalizaÃÃo do uso da Ãgua, alÃm da adequaÃÃo da legislaÃÃo vigente. A discussÃo e deliberaÃÃo pelo Comità de Bacia HidrogrÃfica do Rio Curu foi apresentada como premissa fundamental para efetivaÃÃo da metodologia proposta / The right choice of a model of water allocation in critical periods alleviates the suffering caused by the absence of so precious. Despite the existing water infrastructure, the state of Cearà has been suffering with the problems caused by drought. The methodology for allocation of water, especially in times of scarcity needs to be formatted and discussed with stakeholders in this process. This research aims to propose a strategy for allocating water in lean period for the River Valley Curu, CearÃ, built from the junction of two allocation mechanisms consensus building between users and economic instruments. It is shown that for this water use in Curu Valley is dominantly in the activity irrigation. Thus the proposed strategy consists of the definition of a system of priorities for the use of intra-sectoral water for irrigation from the payment of charges for water use varies depending on the long-term warranty. The funds raised from this collection will be used to pay insurance and financial compensation, in dry years, users with lower collateral. The proposed allocation methodology achieved satisfactory results regarding the criteria of economic efficiency, legitimacy and political sustainability, equity, financial sustainability and adaptability. For its effective implementation were suggested appropriate measures for monitoring, control and supervision of water use, the adequacy of current legislation. The discussion and deliberation by the committee River basin Curu was presented as a prerequisite for realization of the proposed methodology
12

Physiological responses of pepper plant (Capsicum annuum L.) to drought stress

Mardani, Sara, Tabatabaei, Sayyed Hassan, Pessarakli, Mohammad, Zareabyaneh, Hamid 25 January 2017 (has links)
Water shortage is the most important factor constraining agricultural production all over the world. New irrigation strategies must be established to use the limited water resources more efficiently. This study was carried out in a completely randomized design with three replications under the greenhouse condition at Shahrekord University, Shahrekord, Iran. In this study, the physiological responses of pepper plant affected by irrigation water were investigated. Irrigation treatments included control (full irrigation level, FI) and three deficit irrigation levels, 80, 60 and 40% of the plant’s water requirement called DI80, DI60, and DI40, respectively. A no plant cover treatment with three replications was also used to measure evaporation from the soil surface. Daily measurements of volumetric soil moisture (VSM) were made at each 10 cm intervals of the soil column, considered as a layer. The differences between the measured VSM and the VSM in the next day and evaporation rate at the soil surface at the same layer of the no plant cover treatment were calculated. Eventually, by considering the applied and collected water in each treatment, evapotranspiration (ETC) and root water uptake (RWU) in each layer per day were estimated. Furthermore, fruit number per plant, fresh fruit weight/day, root fresh/dry weight, shoot fresh/dry weight, root zone volume, root length and density, crop yield, and water use efficiency (WUE) were measured under different water treatments. The results showed that the maximum and minimum of all the studied parameters were found in the FI and DI40 treatments, respectively. ETC in the DI80, DI60, and DI40 treatments were reduced by 14.2, 37.4, and 52.2%, respectively. Furthermore, applying 80, 60, and 40% of the plant’s water requirement led to crop yield reduction by 29.4, 52.7, and 69.5%, respectively. The averages of root water uptakes (ARWUs) in the DI80, DI60, and DI40 treatments reduced by 17.08, 48.72, and 68.25%, respectively. WUE and crop yield also showed no significant difference in the FI and DI80 treatments. Moreover, in the DI80 treatment the reduced rate of water uptake was less than the reduced rate of plant's applied water. According to these results, it can be concluded that 20% deficit irrigation had no significant reduction on the yield of pepper, but above this threshold, there was an adverse effect on the growth and yield. Therefore, for water management in the regions with limited water resources, plant's applied water can be decreased around 20%.
13

Towards Sustainable Use of Groundwater Resources: Aquifer 23, La Mancha-Spain.

Doncel Fuentes, Pablo January 2015 (has links)
La Mancha Plain lies in the core of Spain and partially stretches over the Guadiana River Upper Basin (UGB), is one of the most arid regions of the Iberian Peninsula, indeed “La Mancha” in Arabic means “the dry”, and also houses a vast Aquifer that has supported the related numerous marshlands and hydro-ecosystems in harmony with the human development till the 1970s, when the “Agrarian Green Revolution” commenced. Land reclamation over River and lagoon beds joined to the irrigation implementation of more than 150.000 Ha have badly bled the water resources to the maximum usable limit, lowering the phreatic table down to 60 meters, provoking a serious ecological damage for the 25.000 Ha of wetlands highly dependent on shallow phreatic levels. Recently, Nature granted the wettest period ever registered in the area (2009-2012) which caused an incredible natural replenishment of that Aquifer deficit. However, even though several costly plans and policies have been undertaken, it is still pending to effectively control the extractions, to manage the Aquifer within a portion allowing a certain continuous upwelling to enliven the Guadiana River real spring, and also, to adjust the essential agriculture sector to the environmental conditions and carrying capacity of the system.
14

Multispectral remote sensing of vegetation responses to groundwater variability in the greater floristic region of the Western Cape, South Africa

Chiloane, Chantel Nthabiseng January 2021 (has links)
>Magister Scientiae - MSc / Groundwater dependent vegetation (GDV) communities are increasingly threatened by the transformation of the natural environment to different land use/land cover, over-exploitation of groundwater resources and the proliferation of invasive species within the Cape Floristic Region (CFR). These changes affect the groundwater regime, level, and quality, which supports GDV. Natural resource managers often lack an understanding at appropriate scales of the nature of dependency of GDV to make informed sustainable decisions. This work thus assesses the spatial distribution of GDV and their responses to groundwater variability within the Cape floristic region from June 2017 to July 2018. To achieve this aim, firstly a literature review on the background of GDV, threats and the impact of climate change was assessed.
15

Dynamics of Water Supply and Demand in the Bandama River Watershed of Cote d'Ivoire

Traore, Sarah Alima 12 May 2022 (has links) (PDF)
Water is a fundamental human right supporting life, health, and livelihoods. Yet water-related issues are ranked among the top five global economic risks (WEF, 2020). About two-thirds (4 billion) of the world's population live with severe water scarcity for at least one month, of which about 48% live in both India and China (Mekonnen et al., 2016). In Côte d'Ivoire, the Bandama River, one of the largest in the country, has struggled to meet expected demand, causing recurrent water and electricity shortages. The city of Bouaké in Côte d'Ivoire and neighboring towns experienced a severe water shortage in 2018 with the drying up of the water supply reservoir (Loka along the Bandama River), affecting 70% of the population causing difficult economic and social conditions. To fully understand this dimension of water scarcity in the Bandama watershed, this study models current water availability using SWAT and assesses the current watershed system in Cote d’Ivoire. Model calibration and validation performances were suboptimal. However, the model gave important information about the dominant process and the critical areas of the watershed. This information guided the development of strategies to build resilience in the water supply system through institutional and stakeholder-driven approaches.
16

Assessing the perceptions of consumers on wastewater reuse in the Vaal Triangle / Lelethu Conelia Bungu

Bungu, Lelethu Conelia January 2014 (has links)
Many countries, including South Africa, are facing the reality of insufficient water supplies to meet their present and future water demands due to decreasing freshwater availability and increasing demand. Increased populations and climate changes further exacerbate the problem. South Africa is considered the thirtieth driest country in the world with limited supplies of water which are unevenly distributed. Thus there is a need for alternative water sources to augment the freshwater supply. Wastewater reuse has been identified worldwide as a viable option to augment water supplies. While technologies are available to ensure proper treatment of wastewater to even potable standards, many countries have experienced public resistance to wastewater reuse due to negative perceptions of consumers. For wastewater reuse initiatives to be successful public acceptance is imperative. The aim of this study was to assess perceptions of consumers in the Vaal Triangle on wastewater reuse. This is the first study conducted in the Vaal Triangle on wastewater reuse hence this information can be valuable in future when wastewater reuse projects are implemented A questionnaire to measure perceptions of consumers on wastewater reuse was developed based on previous studies and distributed to people residing in the Vaal Triangle area. A response rate of 74% (515 completed questionnaires) was obtained from 700 distributed questionnaires. The results showed that socio-demographic factors such as age, race, qualification and level of employment affect the perceptions of consumers on wastewater reuse. Additionally, knowledge of wastewater reuse and water scarcity had a positive effect on consumer‟s perceptions. Some of the major reasons why consumers are not receptive to wastewater reuse are health concerns, lack of trust in the implementing agencies, poor management of the plants and safety of chemicals used to treat the water. Lack of knowledge on wastewater reuse was raised as a major concern in the study. All these concerns need to be addressed to ensure success of wastewater reuse projects within the area. Limitations within the study were identified and recommendations for future research were made. / MBA, North-West University, Potchefstroom Campus, 2015
17

Assessing the potential risk of failing to maintain water supply in the Rand Water area / Londani Phillip Lithole

Lithole, Londani Phillip January 2015 (has links)
The research study focused on assessing the potential risk of failing to maintain water supply in the Rand Water area. The study analysed all factors and areas that contributes to water supply in the Rand Water area; this included municipalities supplied by Rand Water, the Department of Water Affairs and other factors that directly affect Rand Water supply such as population growth, increased urbanisation and acid mine drainage. The objectives of the study were: (a) is to determine the potential risk of failing to maintain supply in the Rand Water supply area, in other words, the likeliness of water not being supplied adequately to customers. (b) generate timely and credible information to determine the understanding, awareness, and acknowledgement by the sampled management group of the existence of the potential water supply risk in the Rand Water supply area. This will be done through a quantitative study. The research study approach that was utilized was a quantitative methodology; this approach included the distribution of questionnaires to all relevant stakeholders in the Rand Water supply area. To address the problems that are highlighted in the problem statement and achieve the objectives of the study these answered questionnaires were then sent to a Statistical consultant at North-West University‟s Potchefstroom Campus, to be analysed using an SPSS Version 21 statistical program. The questionnaires were divided into the three big municipal customers, these municipalities combined takes a total of 74.35% of Rand Water supply; these are Johannesburg Water which is part of the City of Johannesburg Metropolitan Municipality, Ekurhuleni Metropolitan Municipality, Tshwane Metropolitan Municipality and other small municipalities and the Department of Water Affairs‟ officials. Many previous studies also were assessed to be able to help this study establish the seriousness of the water challenge, the amount of work that has already been done, factors contributing to the problem and finally, measures that can be put in place to address the problem. The results that were obtained for this study provided many relationships between this study‟s selected variables and also highlighted the need to put certain strategies in place to be able to control the growing demand for water in the Rand Water system. The name of the Department of Water Affairs has changed many times over the year. It used to be called DWAF (Department of Water Affairs and Forestry, then DWEA (Department of Water and Environmental Affairs, then DWA (Department of Water Affairs) and it has recently been changed to DWS (Department of Water and Sanitation. For the purposes of this study this department will be called DWA (The Department of Water Affairs) The results were very relevant as most of the relationships were found between variables that are practically supposed to be related in order for the problem to be dealt with fruitfully. From these results it could be concluded that the risk of failing to maintain water supply in the Rand Water supply area does exist, if certain factors were allowed to trend the way they‟ve been trending without measures in place to counteract them. It could also be concluded that certain measures have been initiated to deal with the problem; this included water demand management. Results indicated that collective efforts from all stakeholders in the Rand Water supply area will be crucial in addressing the water supply challenge and avoid future failure to supply. To close the gap between previous research studies and this research study recommendations were made. Areas of future research were also highlighted; these are areas that can add value in providing valued information to help the challenge of water shortage in the Rand Water supply area. This area of future research studies will also be crucial in identifying other external factors that were not highlighted in the study but contribute to the problem. This area of future research studies will also help when implementing turnaround strategies to avoid the risk of failing to maintain supply in the Rand Water area as it will be able to highlight a different strategy that deals with the problem holistically. / MBA, North-West University, Potchefstroom Campus, 2015
18

Assessing the perceptions of consumers on wastewater reuse in the Vaal Triangle / Lelethu Conelia Bungu

Bungu, Lelethu Conelia January 2014 (has links)
Many countries, including South Africa, are facing the reality of insufficient water supplies to meet their present and future water demands due to decreasing freshwater availability and increasing demand. Increased populations and climate changes further exacerbate the problem. South Africa is considered the thirtieth driest country in the world with limited supplies of water which are unevenly distributed. Thus there is a need for alternative water sources to augment the freshwater supply. Wastewater reuse has been identified worldwide as a viable option to augment water supplies. While technologies are available to ensure proper treatment of wastewater to even potable standards, many countries have experienced public resistance to wastewater reuse due to negative perceptions of consumers. For wastewater reuse initiatives to be successful public acceptance is imperative. The aim of this study was to assess perceptions of consumers in the Vaal Triangle on wastewater reuse. This is the first study conducted in the Vaal Triangle on wastewater reuse hence this information can be valuable in future when wastewater reuse projects are implemented A questionnaire to measure perceptions of consumers on wastewater reuse was developed based on previous studies and distributed to people residing in the Vaal Triangle area. A response rate of 74% (515 completed questionnaires) was obtained from 700 distributed questionnaires. The results showed that socio-demographic factors such as age, race, qualification and level of employment affect the perceptions of consumers on wastewater reuse. Additionally, knowledge of wastewater reuse and water scarcity had a positive effect on consumer‟s perceptions. Some of the major reasons why consumers are not receptive to wastewater reuse are health concerns, lack of trust in the implementing agencies, poor management of the plants and safety of chemicals used to treat the water. Lack of knowledge on wastewater reuse was raised as a major concern in the study. All these concerns need to be addressed to ensure success of wastewater reuse projects within the area. Limitations within the study were identified and recommendations for future research were made. / MBA, North-West University, Potchefstroom Campus, 2015
19

Assessing the potential risk of failing to maintain water supply in the Rand Water area / Londani Phillip Lithole

Lithole, Londani Phillip January 2015 (has links)
The research study focused on assessing the potential risk of failing to maintain water supply in the Rand Water area. The study analysed all factors and areas that contributes to water supply in the Rand Water area; this included municipalities supplied by Rand Water, the Department of Water Affairs and other factors that directly affect Rand Water supply such as population growth, increased urbanisation and acid mine drainage. The objectives of the study were: (a) is to determine the potential risk of failing to maintain supply in the Rand Water supply area, in other words, the likeliness of water not being supplied adequately to customers. (b) generate timely and credible information to determine the understanding, awareness, and acknowledgement by the sampled management group of the existence of the potential water supply risk in the Rand Water supply area. This will be done through a quantitative study. The research study approach that was utilized was a quantitative methodology; this approach included the distribution of questionnaires to all relevant stakeholders in the Rand Water supply area. To address the problems that are highlighted in the problem statement and achieve the objectives of the study these answered questionnaires were then sent to a Statistical consultant at North-West University‟s Potchefstroom Campus, to be analysed using an SPSS Version 21 statistical program. The questionnaires were divided into the three big municipal customers, these municipalities combined takes a total of 74.35% of Rand Water supply; these are Johannesburg Water which is part of the City of Johannesburg Metropolitan Municipality, Ekurhuleni Metropolitan Municipality, Tshwane Metropolitan Municipality and other small municipalities and the Department of Water Affairs‟ officials. Many previous studies also were assessed to be able to help this study establish the seriousness of the water challenge, the amount of work that has already been done, factors contributing to the problem and finally, measures that can be put in place to address the problem. The results that were obtained for this study provided many relationships between this study‟s selected variables and also highlighted the need to put certain strategies in place to be able to control the growing demand for water in the Rand Water system. The name of the Department of Water Affairs has changed many times over the year. It used to be called DWAF (Department of Water Affairs and Forestry, then DWEA (Department of Water and Environmental Affairs, then DWA (Department of Water Affairs) and it has recently been changed to DWS (Department of Water and Sanitation. For the purposes of this study this department will be called DWA (The Department of Water Affairs) The results were very relevant as most of the relationships were found between variables that are practically supposed to be related in order for the problem to be dealt with fruitfully. From these results it could be concluded that the risk of failing to maintain water supply in the Rand Water supply area does exist, if certain factors were allowed to trend the way they‟ve been trending without measures in place to counteract them. It could also be concluded that certain measures have been initiated to deal with the problem; this included water demand management. Results indicated that collective efforts from all stakeholders in the Rand Water supply area will be crucial in addressing the water supply challenge and avoid future failure to supply. To close the gap between previous research studies and this research study recommendations were made. Areas of future research were also highlighted; these are areas that can add value in providing valued information to help the challenge of water shortage in the Rand Water supply area. This area of future research studies will also be crucial in identifying other external factors that were not highlighted in the study but contribute to the problem. This area of future research studies will also help when implementing turnaround strategies to avoid the risk of failing to maintain supply in the Rand Water area as it will be able to highlight a different strategy that deals with the problem holistically. / MBA, North-West University, Potchefstroom Campus, 2015
20

Water scarcity and electricity generation in South Africa

Wassung, Natalie 12 1900 (has links)
Thesis (MPhil)--Stellenbosch University, 2010. / ENGLISH ABSTRACT: South Africa has a mean annual precipitation far lower than the global average. This is a fundamental constraint to development, especially when the country has already run out of surplus water and dilution capacity. To add further pressure, Southern Africa’s water resources are expected to decrease as a result of climate change. Despite the potential devastation, the country’s response to climate change has been limited. South Africa’s energy sector is dominated by coal power stations and is the country’s primary emitter of carbon dioxide. Given the significantly higher water usage of coal-fired power plants compared to that of most renewable energy power plants, the transition to a clean energy infrastructure might be more successfully motivated by water scarcity than by the promise of reduced carbon emissions. This article analyses more critically the impact of coal-fired electricity generation on South Africa’s water resources, by estimating a water-use figure that extends backwards from the power plant to include water used during extraction of the coal. This figure can then be compared to the water usage of alternative electricity generation options. It is then possible to estimate how much water could be saved by substituting these alternatives in place of additional coal-fired plants. / AFRIKAANSE OPSOMMING: Suid-Afrika se gemiddelde jaarlikse neerslag is baie laer as die wêreldwye gemiddelde. Dit plaas ’n wesenlike beperking op ontwikkeling, veral aangesien die land se surplus water- en verdunningskapasiteit reeds uitgeput is. Om die saak verder te vererger, word verwag dat Suidelike Afrika se waterbronne gaan kleiner word as gevolg van klimaatsverandering. Ten spyte van die potensiële ramp, was die land se reaksie op klimaatsverandering tot dusver baie beperk. Steenkoolkragstasies, wat Suid-Afrika se energiesektor oorheers, is die land se primêre bron van koolstofdioksieduitlating. Gegewe die beduidend hoër waterverbruik van steenkoolkragstasies teenoor dié van die meeste kragstasies wat met hernubare energie werk, kan die verandering na ’n skoonenergie-infrastruktuur meer suksesvol gemotiveer word deur waterskaarste as deur die belofte van verminderde koolstofuitlatings. Hierdie artikel analiseer die impak van steenkoolgedrewe elektrisiteitsopwekking op Suid-Afrika se waterbronne meer krities deur te beraam hoeveel water verbruik word van die kragstasie terug tot by die ontginning van die steenkool. Hierdie syfer kan dan vergelyk word met die waterverbruik van alternatiewe kragopwekkingsopsies. Dit is dan moontlik om te beraam hoeveel water gespaar kan word deur hierdie alternatiewe op te rig in plaas van bykomende steenkoolkragstasies.

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