Thesis (MPhil (Public Management and Planning))--University of Stellenbosch, 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.

<p>In the scope of future population support, agricultural productivity, in particular in sub-Saharan Africa, has to increase drastically to meet the UN’s millennium development goals of eradicating extreme poverty and hunger by 2015. Water availability in the root-zone limits crop production in large parts of the developing world. As competition for fresh water increases, water of lower quality, for example saline or polluted water, is often used for irrigation. Low-cost drip systems are suitable for saline water irrigation because they effectuate a minimisation of salt accumulation, leaf burn and peaks in salt concentration. Nonetheless, all types of saline water irrigation contain the risk for causing soil salinisation. Thus, in order to achieve long-term sustainability of these systems, appropriate management strategies are needed. The choice of management practices may be influenced by local conditions such as climate, soil and irrigation water salinity. A litera-ture review showed that there is a potential for saline water irrigation in sub-Saharan Africa in water scarce areas. Low-cost drip irrigation with saline water (6 dS m-1) was successfully used to irrigate two consecutive crops of tomato in semi-arid South Africa. An integrated ecosystems model was developed to simulate long-term yield and salt accumulation in a drip-irrigated agricultural system for a range of salinities, climates and management techniques. Crop, salt and water balance data from two field experiments conducted in Israel and South Africa, respectively, were used to parameterise and test the model. Emphasis was placed on testing the usability of the model as a tool for evaluating the importance of certain plausible management options of low-cost, drip-irrigation systems. Therefore, particular focus was directed towards correctly describing soil salinity stress on plant growth and soil evaporation from a distributed (wetted and dry) surface. In addition, the model was developed to function for different climates without having to change any other parameters or variables except for the actual climatic data. Simulations were subsequently run over a 30-year period to study long-term yield and salt accumulation in the soil profile for two sites in South Africa, demonstrating the applicability of the model. Model simulations showed that high soil salinities reduced crop growth and thus increased both drainage and soil evaporation. Further, covering the soil with a plastic sheet led to a reduction of soil evaporation and a subsequent increase in both transpiration and drainage. Rainfall was crucial for the leaching of salts from the soil, and thus in regions with low levels of rainfall, a higher leaching fraction of supplied saline irrigation water has to compensate for the lack of rain. However, a high leaching fraction also causes large amounts of salt leaching, which could potentially pollute underlying groundwater and downstream ecosystems. This risk can be mitigated using mulching, which minimises non-productive water losses, thereby lowering irrigation water needs. The choice of irrigation water salinity, frequency of irrigation and soil coverage may differ between the farmer and the regional water manager due to different preferences. Furthermore, the study highlighted how environmental variables such as water use efficiency and radiation use efficiency can be used as indicators of system performance. Whereas the latter is first and foremost a general stress indicator, water use efficiency more precisely describes specific factors such as plant size, allocation patterns and evaporative demand, which will affect the exchange of carbon dioxide and water through the stomata.</p>

MSc Dissertation Submitted to School of Chemical and Metallurgical Engineering, Faculty of Engineering and the Built Environment, University of the Witwatersrand, Johannesburg, South Africa 12 August 2016 / Most mineral processing plants have high water requirements for their operational activities. These plants often function in an environment where water is becoming increasingly scarce. An increase in population will result in an increased demand for water, potentially beyond the limits of supply, and hence increased competition for the resource. In South Africa, Gauteng and the North West Province are likely to be first to experience a shortage of potable water. The key to a sustainable future lies in understanding and utilising resources more efficiently. This holds especially for industries who seek to minimise water usage through better management of resources. The two tools used in this study are the Water Accounting Framework (WAF) and Water Footprinting (WF) method. This research assisted a refinery in the North West Province understand its water usage and move towards operating in a more sustainable manner. Site water management was improved and the objective of this research fulfilled by: (i) Surveying the potable water and the storm water systems with a view to assessing the current water accountability and determining methods to improve accountability; (ii) Determining the water balance for the site and presenting it in the form of a water balance sheet; (iii) Reporting water usage in accordance with the Minerals Council of Australia’s “Water Accounting Framework for the Minerals Industry”; (iv) Calculating the water footprints of the refinery; and (v) Evaluating the water usage at the refinery and identifying ways in which water savings could be achieved. It was seen that the biggest consumer of water was the boilers and utilities section and the biggest loss of water was through evaporation. The refinery potable water requirement (2 280 m3/y) amounted to 0.16% of the daily water use for the Bojanala Platinum District. Four reports (outputs) were generated using the WAF. The four reports generated provide a good indication of the movement of water into, out of and during a process. WFs were calculated for the process. The blue WF was calculated to be 832 363 m3 and the green WF was calculated to be 261 970 m3. The product WF was 43.9 m3/t of base metal produced. There was no grey WF as the site does not discharge polluted water. This research provided an opportunity for the refinery to improve water efficiency onsite as well as improve reporting standards. Water usage was reported using global reporting tools to set a benchmark for the base metals industry. / MT2017

O paisagismo está presente em espaços externos e internos modificando as cidades. O girassol é uma planta anual, com potencial paisagístico. Algumas variedades ornamentais podem ser cultivadas em vasos, bordaduras e maciços, sendo considerada uma cultura com excelentes perspectivas de expansão no Brasil, em função de suas características, como, ampla adaptação aos diferentes ambientes, mas, no entanto, o estresse hídrico diminui o crescimento e a produtividade das plantas. Uma ferramenta que busca racionalizar o manejo hídrico é o condicionador de solo hidrogel empregado em diversos setores da agricultura. Trata-se de um polímero hidrorretentor que possui a capacidade de liberar gradativamente a água e nutrientes retidos na cadeia carbônica, melhorar a drenagem do solo, aumentar a produtividade, diminuir os custos de produção e evitar a perda de nutrientes por percolação e lixiviação. Porém, são necessários estudos direcionados a cada cultura para se realizar a recomendação desse condicionador. A produção de girassol cultivado em vaso tem grande potencial comercial no Brasil e a utilização do hidrogel como condicionador de solo pode permitir a economia hídrica ao longo do ciclo de cultivo. Este trabalho teve por objetivo avaliar as respostas da produção de girassol em vaso sob diferentes doses de hidrogel em duas diferentes épocas sazonais. A pesquisa foi conduzida em casa de vegetação nos períodos de outono/inverno (20/05/2015 a 31/07/2015) e primavera/verão (24/10/2015 a 14/12/2015). O delineamento experimental adotado foi em blocos casualizados (DBC) com 4 doses de hidrogel (0, 6, 12 e 18 gramas por planta) com 6 repetições. A colheita foi realizada aos 60 dias após o transplantio das mudas (DAT). Foram avaliados a massa fresca e seca da parte aérea (MFPA e MSPA); massa fresca e seca das flores (MFF e MSF); massa fresca e seca das raízes (MFR) e (MSR) e volume das raízes (VR). A adição de hidrogel favoreceu a produção de girassol em vaso promovendo economia de água durante todo o ciclo da cultura. A dose de 6 gramas de hidrogel por planta, propiciou a melhor economia hídrica em ambos os experimentos. O período primavera/verão apresentou maior gasto na irrigação quando comparado ao outono/inverno. O diâmetro floral diminuiu em função do aumento das doses de hidrogel em ambos os períodos sazonais. / The landscaping is present in several external and internal spaces modifying the cities. The sunflower is an annual plant with potential landscape use. Some ornamental varieties can be cultivated in pots, borders and massifs, being considered a crop with excellent prospects of expansion in Brazil, due to its characteristics, such as, wide adaptation to different environments, however, water stress decreases growth and productivity of plants. Hydrogel conditioner is a tool that aims to rationalize water soil management used in several sectors of agriculture. The hydrogel is a polymer that has the ability to gradually release water and nutrients retained in the carbon chain, improve soil drainage, increase productivity, decrease production costs and prevent nutrient loss through percolation and leaching. The production of potted sunflower has great potential for commercial growth in Brazil and the use of the hydrogel as a soil conditioner can allow water saving throughout the growing cycle. The objective of this work was to evaluate the responses of potted sunflower production under different doses of hydrogel in two different seasonal seasons. The research was conducted in a greenhouse during the fall / winter (05/20/2015 to 07/31/2015) and spring / summer (24/10/2015 to 12/14/2015). The experimental design was a randomized complete block (DBC) with 4 hydrogel doses (0, 6, 12 and 18 grams per plant) with 6 replicates. Harvesting was performed 60 days after transplanting of the seedlings (DAT). Were evaluated the fresh and dry shoot of the aerial part (MFPA and MSPA); fresh and dry mass of flowers (MFF and MSF); fresh and dry mass of the roots (MFR) and (MSR) and root volume (VR). The addition of hydrogel effectively favored potted sunflower production, promoting water saving throughout the crop cycle. The hydrogel addition favored potted sunflower production, promoting water saving throughout the all crop cycle. The dose of 6 grams of hydrogel per plant, provided the best hydric economy in both experiments. The spring / summer period presented higher irrigation use when compared to autumn / winter. The floral diameter decreased as a function of the increase by hydrogel doses in both seasonal periods.

lt;p align="justify"gt; Este trabalho visa propor uma simulação do instrumento da cobrança pelo uso dos recursos hídricos na bacia hidrográfica do rio Piracicaba no Estado de Minas Gerais. Nesta bacia destacam-se como principais segmentos de usuários, o setor de mineração no alto e médio Piracicaba e o setor de siderurgia que representa o maior complexo siderúrgico da América Latina, com suas plantas instaladas na porção do baixo curso do rio Piracicaba, na região conhecida como Vale do Aço. Inicialmente foram apresentadas as legislações de recursos hídricos a nível federal e estadual, particularmente a do Estado de Minas Gerais, destacando seus avanços em relação à federal. Posteriormente foi caracterizada a bacia hidrográfica considerando aspectos físicos e sócio-econômicos, bem como o levantamento dos principais usos dos recursos hídricos para o ano de 2006. Utilizou-se como principal referencia para a simulação da cobrança pelo uso da água na bacia do rio Piracicaba, a metodologia de cobrança aplicada na bacia do rio Paraíba do Sul, (CEIVAP). A partir dos valores dos parâmetros utilizados naquela bacia estimou-se o valor a ser arrecadado com a cobrança na bacia hidrográfica do rio Piracicaba. Recomenda-se a necessidade de reavaliação da metodologia utilizada quando o Comitê IX da Bacia optar pela implantação da cobrança na bacia do rio Piracicaba podendo ser utilizada a nova fórmula de cobrança do CEIVAP que define novos critérios e valores para a cobrança a partir de 2007. Por fim concluiu-se que de uma forma geral a cobrança pelo uso de recursos hídricos na bacia atende os objetivos da legislação federal e estadual de recursos hídricos.lt;/pgt; / lt;p align="justify"gt; This work seeks to simulate the implementation of the management instrument of water use charge in the Piracicaba river basin in the State of Minas Gerais. In this watershed, those which stand out as main user segments are the mining sector, in the upper and medium Piracicaba basin, where the largest minerary complex of the world is located; and the metallurgy sector, that has its largest metallurgical complex in Latin America installed mainly in the lower Piracicaba basin, in the area known as Steel Valley. Initially, the legislation of water resources was presented at federal and state level, particularly of the State of Minas Gerais, detaching its progresses in relation to the norms of federal ambit. Then it was presented a description of the river basin considering physical, climatic and socioeconomic aspects, as well as the survey of the main uses of the water resources in the basin in the year of 2006. It was presented the volume of water granted in the basin for superficial and underground abstractions, per user sector. For the simulation of the water use charge in the basin, it was used the methodology of CEIVAP for the charge in the Paraíba do Sul watershed. From the values of the parameters used in that basin, it was estimated the value to be collected with the charge in the Piracicaba watershed. Then, recommendations were presented for the reevaluation of this methodology when the Basin Committee decides to implement the charge, once the current formula used by CEIVAP for water use charge will be reformulated by 2007. Finally it was concluded that, in a general way, the water use charge in the basin attains the objectives of the federal legislation - the "Water Law", as Law nº 9.433/97 is known -, once it recognizes the economical value of water and gives dimension of its real value to the user; works as an incentive for the user for the rationalization of its use and propitiates the means to obtain funds, what makes possible the financing of programs and interventions foreseen in Water Resources Plans.lt;/pgt;

No description available.

abstract: In the recent past, Iraq was considered relatively rich considering its water resources compared to its surroundings. Currently, the magnitude of water resource shortages in Iraq represents an important factor in the stability of the country and in protecting sustained economic development. The need for a practical, applicable, and sustainable river basin management for the Tigris and Euphrates Rivers in Iraq is essential. Applicable water resources allocation scenarios are important to minimize the potential future water crises in connection with water quality and quantity. The allocation of the available fresh water resources in addition to reclaimed water to different users in a sustainable manner is of the urgent necessities to maintain good water quantity and quality. In this dissertation, predictive water allocation optimization models were developed which can be used to easily identify good alternatives for water management that can then be discussed, debated, adjusted, and simulated in greater detail. This study provides guidance for decision makers in Iraq for potential future conditions, where water supplies are reduced, and demonstrates how it is feasible to adopt an efficient water allocation strategy with flexibility in providing equitable water resource allocation considering alternative resource. Using reclaimed water will help in reducing the potential negative environmental impacts of treated or/and partially treated wastewater discharges while increasing the potential uses of reclaimed water for agriculture and other applications. Using reclaimed water for irrigation is logical and efficient to enhance the economy of farmers and the environment while providing a diversity of crops, especially since most of Iraq’s built or under construction wastewater treatment plants are located in or adjacent to agricultural lands. Adopting an optimization modelling approach can assist decision makers, ensuring their decisions will benefit the economy by incorporating global experiences to control water allocations in Iraq especially considering diminished water supplies. / Dissertation/Thesis / Doctoral Dissertation Civil, Environmental and Sustainable Engineering 2019

This thesis deals with the estimation of plant-atmosphere trace gas exchange and isotopic discrimination from atmospheric concentration measurements. Two space scales were investigated: canopy and regional. The canopy-scale study combined a Lagrangian model of turbulent dispersal with ecophysiological principles to infer vertical profiles of fluxes of CO2, H2O and heat as well as carbon and oxygen isotope discrimination during CO2 assimilation, from concentration measurements within a forest. The regional-scale model used a convective boundary layer budget approach to infer average regional isotopic discrimination and fluxes of CO2 and sensible and latent heat from the evolution during the day of boundary layer height and mean concentrations of CO2 and H2O, temperature and carbon and oxygen isotope composition of CO2. For the canopy study, concentrations of five scalar quantities, CO2, 13CO2, C18O16O, H2O and temperature, were measured at up to nine heights within and above a mixed fir and spruce forest in central Siberia over several days just after snow melt in May 2000. Eddy covariance measurements of CO2, H2O and heat fluxes were made above the canopy over the same period, providing independent verification of the model flux estimates. Photosynthesis, transpiration, heat exchange and isotope discrimination during CO2 assimilation were modelled for sun and shade leaves throughout the canopy through a combination of inversion of the concentration data and principles of biochemistry, plant physiology and energy balance. In contrast to the more usual inverse modelling concept where fluxes are inferred directly from concentrations, in this study the inversion was used to predict unknown parameters within a process-based model of leaf gas and energy exchange. Parameters relating to photosynthetic capacity, stomatal conductance, radiation penetration and turbulence structure were optimised by the inversion to provide the best fit of modelled to measured concentration profiles of the five scalars. Model results showed that carbon isotope discrimination, stomatal conductance and intercellular CO2 concentration were depressed due to the low temperatures experienced during snow melt, oxygen isotope discrimination was positive and consistent with other estimates, radiation penetrated further than simple theoretical predictions because of leaf clumping and penumbra, the turbulence coherence was lower than expected and stability effects were important in the morning and evening. For the regional study, five flights were undertaken over two days in and above the convective boundary layer above a heterogeneous pine forest and bog region in central Siberia. Vertical profiles of CO2 and H2O concentrations, temperature and pressure were obtained during each flight. Air flask samples were taken at various heights for carbon and oxygen isotopic analysis of CO2. Two budget methods were used to estimate regional surface fluxes of CO2 and plant isotopic discrimination against 13CO2 and C18O16O, with the first method also used to infer regional sensible and latent heat fluxes. Flux estimates were compared to ground-based eddy covariance measurements. Model results showed that afternoon estimates for carbon and oxygen isotope discrimination were close to those expected from source water isotopic measurements and theory of isotope discrimination. Estimates for oxygen isotope discrimination for the morning period were considerably different and could be explained by contrasting influences of the two different ecosystem types and non-steady state evaporative enrichment of leaf water.

環境資本中的水資源是自然生態必備要素，隨著經濟發展，水資源即漸成經濟財，早期重視農業的結果，如今與二、商及民生用水一起競用有限水資源，加上新的環境生態問題，均使水資源面臨短缺之危機；而台灣地處亞熱帶，雨量雖丰，但因其地形特殊（如南部地區），七八成地表逕流量迅速流入海中，因此河流枯水期長，流量小，如不經適當開發即面臨缺水的危機；水資源之管理有如多頭馬車，如中央有水利司、水資會、工業局、環保署，地方有水利局、水庫管理局等，導致每遇缺水時，即發生各單位協調困難，使問題無法有效解決。以上因素使未來水資源問題，不僅只為水源之開發，水源之維護與分配亦需獲得應有的重視，因此本文嘗試由效率面，就水源的管理及自來水供應予以探討，並提出較合理的方式以解決水資源問題。 　　對於民生用水方面，一般推估其用水量多是以每年人口成長數推算，本文則以實証方式找出除人口外之可能影響水的因素，以供未來決定國內民生用水需水量之參考。 　　本研究以水資源之功能分成水管理與自來水使用，水管理部份現行制度下己產生不少問題，本研究建議採水利區為一個管理單元，除可解決現今事權不統一主窘境外，尚可配合各河川水文特性，建立符合當地自然景觀之特色，於環境保育日漸興起之際，採集水區管理局經營實為當務之急。 　　自來水使用現今分成二個供水單位一台北自來水事業處及台灣省自來水公司，二者均為公用事業，過去政府從事各項水利建設，在眾多重大工程一起競用有限資金下，唯有採行之統一管理、分區經營才可解決，但此種經營方式形成水費需經民意機關監督，造成低水費政策，在原水成本不斷上升，己無法彌補公司之營運成本之際，本研究建議引入俱樂部財模型以配合水利區管理局分區成立民營水公司以解決目前難題。 　　實証部份，限於樣本不足，如能採月資料將更可使模型結果完滿，以本模型而言，所得仍為影響各縣市需水量最重要因素，且彈性皆小於一，足証水仍為民生必需品；其次為平均成本，只有四個縣市顯著：台中市及台南價格彈性小於一，表示必需品，高雄市及北縣基隆大於一，富有彈性，表示價格上升時，需求量減少很大；雨量部份計有臺北縣基隆市、高雄縣、澎湖、雲林四個區域顯著，且彈性為正表雨量上升，用量亦增加；溫度方面，只有台南顯著，一般而言應為正相關，有可能是溫度上升使水質差不願使用，此由歷年降雨量較其他縣市為少下，使水體無法有效溶解使水質變差可茲証明。需水量之估計不僅要考慮人口，尚應加上所得、價格、雨量、溫度甚或各用水設備（如馬桶個數）等，將可使實証結果更加完備。 　　本文主題一水屬環境資本之一支，它是否為再生系統，端視二種力量而定：一為水污染，嚴重的水污染將破壞水體，非但人類無法取用，水中生物及仰賴水而活之動植物亦無法悻免，如淡水河即是一例；二為新技術開發或原有技術改良以提高水的資本存量及生產力，如英國泰晤士河流域即是整治成功之最佳例証；如後者力量大於前者，水就是再生系統，反之其命運如礦產一般只有耗竭一途，而現今的水資源問題除應改供給導向之水資源政策為需求導向外，積極開發水源節水及循環用水、改進現行組織系統均為解決目前水資源難題之途。

<p>To address increasing irrigation water demand consecutive to the increasing population pressure in terms of food demand, there is an imperative of developing relevant mechanisms to regulate irrigation water consumption patterns. A radical shift from uncontrolled flooding irrigation as currently practiced by farmers in Mugerero paddy farming zone towards efficient allocation and use of water resources is important to save water that could be allocated to other water users.</p><p>This paper surveys current and past views on the way irrigation water is allocated in the irrigation scheme of Mugerero and how farmers are using water for paddy production purpose. The existing irrigation water practices as well as paddy productivity are assessed and the results are expected to be useful for water policy professionals, while addressing the growing water demand. According to the respondents, the causes of low paddy yields are the increasing and uncontrolled extension of paddy farming, non adapted irrigation infrastructure and water pricing systems as well as lack of updated knowledge and technologies on irrigation. These issues faced by the paddy farmers have led to pronounced economic, social and environmental consequences which are manifested in conflicts over irrigation water use, increasing soil salinity and pollution, destruction of infrastructure and above all, low irrigation paddy yields.The identification of the core problem in the irrigation system might be important for water managers as it would provide a starting point to establish comprehensive baseline towards efficient irrigation water allocation and use. This would improve paddy productivity within the formal as well as the growing informal paddy farming referred to “hors- perimeter” in the low land of Imbo region.</p>