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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.
151

Vårt gemensamma vatten : Konflikt eller samarbetsområde? En komparativ fallstudie om Aralsjöns och Victoriasjöns delade vatten

Paulin, Oskar January 2016 (has links)
All life on Earth is based on and is constantly dependent on flows of water through every plant, every animal and every human body. This makes water Earth's most important natural resource. Lack of water can cause enormous suffering to faculty of agriculture, industry and local ecosystem. Although models, research and pure common sense shows the rational and positive in cooperating on shared water resources, it takes time to build up a stable cooperation between the different political states. Although a generalization is not possible, it is possible to find patterns that despite prevailing political situation, there is a willingness and desire to override political differences and seek a sustainable development in the region. Today there is a consensus among scientists that shared water combined with water shortages, often causes political conflicts. These disputes rather get the parties to realize that they are dependent on each other to get the water they need, and that they find ways to cooperate.
152

Institutions and decentralised urban water management

Livingston, Daniel John, Civil & Environmental Engineering, Faculty of Engineering, UNSW January 2008 (has links)
Physically decentralised water management systems may contribute to improving the sustainability of urban water management. Any shift toward decentralised systems needs to consider not just physical system design but also social values, knowledge frames, and organisations, and their interconnections to the physical technology. Four cases of recent Australian urban water management improvement projects were researched using qualitative methods. Three cases were of decentralised water management innovation. The other was of a centralised system, although decentralised options had been considered. These cases were studied to identify institutional barriers and enablers for the uptake of decentralised systems, and to better understand how emerging environmental engineering knowledge might be applied to overcome an implementation gap for decentralised urban water technologies. Analysis of each case focused on the institutional elements of urban water management, namely: the values, knowledge frames and organisational structures. These elements were identified through in-depth interviews, document review, and an on-line survey. The alignment of these elements was identified as being a significant contributor to the stability of centralised systems, or to change toward decentralised systems. A new organisational home for innovative knowledge was found to be common to each case where decentralised innovation occurred. ??Institutional entrepreneurs??, strong stakeholder engagement, and inter-organisational networks were all found to be linked to the creation of shared meaning and legitimacy for organisational and technological change. Existing planning frameworks focus on expert justification for change rather than institutional support for change. Institutional factors include shared understandings, values and organisational frameworks, and the alignment of each factor. Principles for, and examples of, appropriate organisational design for enabling and managing decentralised technological innovation for urban water management are proposed. This research contributes to the understanding of the institutional basis and dynamics of urban water management, particularly in relation to physical centralisation and decentralisation of urban water management technologies and, to a lesser extent, in relation to user involvement in urban water management. Understanding of factors that contribute to enabling and constraining decentralised technologies is extended to include institutional and organisational factors. New and practical pathways for change for the implementation of decentralised urban water systems are provided.
153

Institutions and decentralised urban water management

Livingston, Daniel John, Civil & Environmental Engineering, Faculty of Engineering, UNSW January 2008 (has links)
Physically decentralised water management systems may contribute to improving the sustainability of urban water management. Any shift toward decentralised systems needs to consider not just physical system design but also social values, knowledge frames, and organisations, and their interconnections to the physical technology. Four cases of recent Australian urban water management improvement projects were researched using qualitative methods. Three cases were of decentralised water management innovation. The other was of a centralised system, although decentralised options had been considered. These cases were studied to identify institutional barriers and enablers for the uptake of decentralised systems, and to better understand how emerging environmental engineering knowledge might be applied to overcome an implementation gap for decentralised urban water technologies. Analysis of each case focused on the institutional elements of urban water management, namely: the values, knowledge frames and organisational structures. These elements were identified through in-depth interviews, document review, and an on-line survey. The alignment of these elements was identified as being a significant contributor to the stability of centralised systems, or to change toward decentralised systems. A new organisational home for innovative knowledge was found to be common to each case where decentralised innovation occurred. ??Institutional entrepreneurs??, strong stakeholder engagement, and inter-organisational networks were all found to be linked to the creation of shared meaning and legitimacy for organisational and technological change. Existing planning frameworks focus on expert justification for change rather than institutional support for change. Institutional factors include shared understandings, values and organisational frameworks, and the alignment of each factor. Principles for, and examples of, appropriate organisational design for enabling and managing decentralised technological innovation for urban water management are proposed. This research contributes to the understanding of the institutional basis and dynamics of urban water management, particularly in relation to physical centralisation and decentralisation of urban water management technologies and, to a lesser extent, in relation to user involvement in urban water management. Understanding of factors that contribute to enabling and constraining decentralised technologies is extended to include institutional and organisational factors. New and practical pathways for change for the implementation of decentralised urban water systems are provided.
154

Coeficiente de cultivo e lâminas de irrigação do Maracujazeiro Amarelo nas condições semiáridas / Coefficient of cultivation and irrigation of yellow passion fruit in semiarid conditions.

Nogueira, Eliomar January 2011 (has links)
NOGUEIRA, Eliomar. Coeficiente de cultivo e lâminas de irrigação do Maracujazeiro Amarelo nas condições semiáridas. 2011. 70 f. : Dissertação (mestrado) - Universidade Federal do Ceará, Centro de Ciências Agrárias, Departamento de Engenharia Agrícola, Programa de Pós-Graduação em Engenharia Agrícola, Fortaleza-CE, 2007. / Submitted by demia Maia (demiamlm@gmail.com) on 2016-06-22T14:41:16Z No. of bitstreams: 1 2011_dis_enogueira.pdf: 6330872 bytes, checksum: b45642fa70c9e615f28157c7d80c869a (MD5) / Approved for entry into archive by demia Maia (demiamlm@gmail.com) on 2016-06-22T14:55:06Z (GMT) No. of bitstreams: 1 2011_dis_enogueira.pdf: 6330872 bytes, checksum: b45642fa70c9e615f28157c7d80c869a (MD5) / Made available in DSpace on 2016-06-22T14:55:06Z (GMT). No. of bitstreams: 1 2011_dis_enogueira.pdf: 6330872 bytes, checksum: b45642fa70c9e615f28157c7d80c869a (MD5) Previous issue date: 2007 / This work aims to determine the crop coefficie nt of the yellow passion fruit and to find irrigation levels that can raise the yield a nd quality of passion fruit production under the environmental conditions of the semiarid re gion of Piaui (Br). The experiment was conducted at the Projeto Piloto de Fruticultura Irrigada (Irrigated Fruit Culture Pilot Project) of the CODEVASF, in Santa Rosa, PI (06 ° 47 '5 6''S, 42 ° 17' 17''W). We used randomized blocks with six treatments and four replications, with four plants to a plot. The treatments (irrigation levels) were defined as percentages of the reference evapotranspiration (ETo): T1 (25% ETo), T2 (50% ETo), T3 (75% ETo), T4 ( 1 00% ETo), T5 (125% ETo) and T6 (150% ETo). It was installed a battery with three tensiom eters per treatment at depths of 0.10 m, 0.30 m and 0.50 m, to monitor the soil water. Determining the crop coefficient (Kc), we used the soil water balance, and for obtaining that, two batteries were installed, with tensiometers placed at depths of 0.10 m, 0.30 m 0.50 m within a radius of 0.30 m and 0.60 m from the stems of the plants in T4. The Kc values were estimated in the 41-240 days a fter transplanting (DAT). The irrigation le vels of 408.25 mm (T1), 463.41 mm (T2) 535.11 mm (T3), 609.98 mm (T4), 704.71 mm (T5) and 826.02 mm (T6) were applied on performing the experiment. We evaluated the morphological and physiologic al growth variables of yellow passion fruit (plant height, stem diameter, number of internod es, leaf area, leaf number and leaf water potential) and production traits (yield, fruit numb er, fruit weight, fruit transverse diameter and fruit longitudinal diameter). Analysis of varia nce showed that the irrigation significantly influenced stem diameter (P <0.05) in assessments conducted in December 2009, January and February 2010; leaf area (P < 0.01) for assessments conducted from Januar y to April 2010; number of leaves (P <0.05) for assessments conducted in March 2010 and (P <0.01) in April 2010; leaf water potential (P <0.01) at all testing times. Besides, the number of fruits (P<0.05), the average fruit weight (P <0.05) and the productivity (P <0.05) were found significantly responding to the irrigation level. Maximum yield (6763 kg ha-1) was obtained in 60 days of harvest, ie 25% of potential annual production of passion fruit was obtained with an irrigation level of 763.80 mm...Estimating to its full potential to the first year of production we obtained a value of 27,052 kg ha-1 yr -1. As for the average fruit weight, it ranged from 0.207 kg (T6) to 0,159 kg (T1). The maximum number of fruits (33 119 fruit ha -1) was obtained with an irrigation level of 760.21 mm. The Kc values ranged from 0.43 to 1.04 with a maximum recorded value at 211 to 220 DAT. The average Kc obtained at the vegetative stage, was 0.57, and the average Kc at the production stage(flower ing and fruiting)was 0.94. Therefore: The irrigation level most suitable for the passion fruit must be between 72% and 100% ETo; The assessed morphophysiological growth variables of the yellow passion fruit are influenced by the variation of irrigation level applied to culture; The yield, average weight and fruit number of the yellow pa ssion plant are also influenced by the same variation of irrigation level / Coeficiente de cultivo e lâminas de irrigação do maracujazeiro amarelo nas condições semiáridas. Orientador: Valdemício Ferreira de Sousa. Conselheiros: Thales Vinícius de Araújo Viana, Luís de França Camboim Neto. O objetivo do trabalho foi determinar o coeficiente de cultivo do maracujazeiro amarelo e definir lâminas de irrigação capazes de elevar a produtividade da cultura e a qualidade da produção nas condições ambientais da região semiárida do Piauí. O experimento foi realizado na área do Projeto Piloto de Fruticultura Irrigada da CODEVASF, no município de Santa Rosa, PI (06° 47’ 56’’ S, 42° 17’ 17’’ W). Utilizou-se delineamento experimental blocos ao acaso com seis tratamentos e quatro repetições, parcela com quatro plantas úteis. Os tratamentos (lâminas de irrigação) foram definidos em função de percentagens da evapotranspiração de referência (ETo): T1 (0,25*ETo), T2 (0,50*ETo), T3 (0,75*ETo), T4 (1,00*ETo), T5 (1,25*ETo) e T6 (1,50*ETo). Para o monitoramento da água no perfil do solo instalou-se uma bateria com três tensiômetros por tratamento nas profundidades de 0,10 m; 0,30 m e 0,50 m. Para determinação do coeficiente de cultivo (Kc), utilizou-se o balanço de água no solo e para tanto, foram instaladas duas baterias com tensiômetros distribuídos nas profundidades de 0,10 m; 0,30 m e 0,50 m, num raio de 0,30 m e 0,60 m do caule das plantas no T4 . No período de 41-240 dias após transplantio (DAT) estimou-se valores de Kc. Na execução do experimento foram aplicadas as respectivas lâminas de irrigação 408,25 mm (T1), 463,41 mm (T2), 535,11 mm (T3), 609,98 mm (T4), 704,71 mm (T5) e 826,02 mm (T6). Foram avaliadas as características morfofisiológicas de crescimento do maracujazeiro amarelo (altura da planta, diâmetro do caule, número de internós, área foliar, número de folhas e potencial hídrico foliar; características de produção (produtividade, números de frutos, peso médio de frutos, diâmetros transversal e longitudinal de frutos). A análise de variância mostrou que as lâminas de irrigação influenciaram significativamente o (diâmetro de caule (P<0,05) nas avaliações realizadas em dezembro de 2009, janeiro e fevereiro de 2010; área foliar (P<0,01) para avaliações realizadas de janeiro a abril de 2010; número de folha (P<0,05) para as avaliações realizadas em março 2010 e (P<0,01) para abril de 2010); o potencial hídrico nas folhas (P<0,01) em todas as épocas de avaliação. E foi significativo o número de frutos (P<0,05), peso médio do fruto (P<0,05) e a produtividade (P<0,05). A produtividade máxima (6.763 kg ha-1) obtida em 60 dias de colheita, isto é, 25% do potencial produtivo anual do maracujazeiro foi obtida com aplicação da lâmina de 763,80 mm e estimando-se para seu potencial total para o primeiro ano de produção obteve-se o valor de 27.052 kg ha-1 ano-1; o peso médio de fruto variou de 0,207 kg (T6) e 0,159 kg (T1); foi registrado o número máximo de frutos (33.119 frutos ha-1) com lâmina de 760,21 mm. Os valores de Kc variaram de 0,43 a 1,04 com registro de máximo valor em 211 a 220 DAT. E o Kc médio obtido para a fase vegetativa foi de 0,57 e para fase de produção (floração e frutificação) de 0,94. Conclui-se que, as lâminas de irrigação mais adequadas para maracujazeiro amarelo se situam entre o equivalente 0,72*ETo e 1,00*ETo; as características morfofisiológicas de crescimento do maracujazeiro amarelo avaliadas, são influenciadas pela variação de lâminas de irrigação aplicada à cultura; a produtividade do maracujazeiro amarelo, peso médio e número de frutos são influenciados pela diferenciação de lâminas de irrigação aplicada à cultura.
155

Capacidade de interceptação pelas árvores e suas influências no escoamento superficial urbano / Capacity of interception by trees and influences on urban runoff

Alves, Patrícia Layne 16 April 2015 (has links)
Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2015-10-28T12:52:56Z No. of bitstreams: 2 Tese - Patrícia Layne Alves - 2015.pdf: 6139087 bytes, checksum: 2d26cabd2939ffa1c0a67132b80a0490 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2015-10-28T12:54:31Z (GMT) No. of bitstreams: 2 Tese - Patrícia Layne Alves - 2015.pdf: 6139087 bytes, checksum: 2d26cabd2939ffa1c0a67132b80a0490 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2015-10-28T12:54:31Z (GMT). No. of bitstreams: 2 Tese - Patrícia Layne Alves - 2015.pdf: 6139087 bytes, checksum: 2d26cabd2939ffa1c0a67132b80a0490 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2015-04-16 / Fundação de Amparo à Pesquisa do Estado de Goiás - FAPEG / Problems related to water, in the urban environment, have drawn attention in the face of the problem caused by its lack and/or excess. Among this backdrop there is the tumultuous occupation of urban space that combined with the suppression of soil coverage and vegetation leads to the urban runoff higher volume, pollution and shorter time to peak discharge. In this context, the benefits of urban afforestation are present, which besides the aesthetic value added to space, set up physical barriers to stormwater, favoring its retention, storage and infiltration into the soil. This study aims to evaluate the capacity of rainfall interception treetops the some species, reduce the volume of urban runoff, slow the flow peaks, as well as to expand the attention span of an urban watershed. The research was field experiments with recurrent arboreal species in the urban afforestation of Uruaçu, Goiás, using pluviographs, trunk collectors and water level sensor. From the use of interception parameters determined in this study, computer simulations using the Storm Water Management Model Model (SWMM) were performed, starting from the proposition of scenarios with different types of territorial installment associated with the Low Impact Development practices (LID) and urban forestry. During the data collection period 2012/2013, the rainfall events had a median of accumulated rainfall of 16.7mm. During this period, the median values of interception were Mangifera indica - 8.0mm; Pachira aquatica - 7.4mm; Licania tomentosa - 7.2mm; and Caesalpinia peltophoroides - 4.8mm. The period of data collection relating to 2013/2014, the median precipitation of rainfall events were 20.7mm, and the median values for interception and stemflow were respectively: 5.7mm and 0.1mm for Mangifera indica; 4.5mm and 0.2mm for Licania tomentosa; and 3.8mm and 0.3mm for Tabebuia ochracea. The delay at the start of average rains caused by tree species was 3min. The presence of individual trees afforded a median delay in the peak time of 3 min, a reduction of the peak flow of 0.8 mm/min and runoff of 4.7mm/min. Through simulations with the scenario where the wooded urban planning aggregated all LID techniques employed in this study, it was possible to achieve a reduction in peak flows in 3.42m³ / s, compared to conventional design; allowing storage of a volume of water in 4470.59m³ local infiltration proposed structures; and delay the peak flows of up to 6 min. This thesis confirms the interference of the individual characteristics of the species in the rain interception capability by their canopies and reducing runoff, highlighting the need for careful definition of the species that make up the urban forestry; testifies the existence of variations in interceptions in relation to rainfall events and during their occurrence; as well as quantitative data points precipitate volume reduction and drained by the tree individual presence in urban areas. Their research shows that, alone, afforestation and LID techniques cause little reduction in volume and flow and little delay in time to peak flow, while combined contribute significantly to drainage. This study differs from the use of recording rain gauges and linígrados for the measurement of precipitation and runoff directly under the canopy of individual trees in an urban environment; and adds to SWMM the insertion of arboreal benefits in hydrological simulation. / Os transtornos relacionados à água, no ambiente urbano, têm merecido destaque diante da problemática causada pela sua falta e/ou excesso. Dentre este cenário, tem-se a ocupação desordenada do espaço urbano, que aliada à supressão da cobertura natural do solo e da vegetação acarretam ao escoamento urbano maior volume, poluição e menor tempo ao pico de vazão. Neste contexto, insere-se os benefícios da arborização urbana, que além do valor estético que agrega ao espaço, oferece barreiras físicas às águas pluviais, favorecendo a sua retenção, armazenamento e infiltração no solo. Este estudo se propõe a avaliar a capacidade de algumas espécies arbóreas em interceptar as águas de chuva pelas suas copas, reduzir o volume de escoamento superficial urbano, retardar os picos de vazão, bem como de ampliar o tempo de concentração de uma bacia hidrográfica urbana. A pesquisa teve experimentos de campo com espécies arbóreas recorrentes à arborização urbana de Uruaçu, Goiás, utilizando pluviógrafos, coletores de tronco e linígrafos. A partir do emprego dos parâmetros de interceptação determinados neste estudo, foram realizadas simulações computacionais com o uso do modelo Storm Water Management Model (SWMM), partindo da proposição de cenários com diferentes tipologias de parcelamento territorial associados às práticas de Low Impact Development (LID) e à arborização urbana. Durante o período de coleta de dados de 2012/2013, os eventos chuvosos tiveram mediana de 16.7mm de precipitação acumulada. Neste período, os valores medianos de interceptação foram: Mangifera indica – 8.0mm; Pachira aquatica - 7.4mm; Licania tomentosa – 7.2mm; e, Caesalpinia peltophoroides - 4.8mm. No período de coleta dados referente a 2013/2014, as precipitações medianas dos eventos chuvosos foram de 20.7mm, e os valores medianos para interceptação e escoamento pelo tronco, foram respectivamente: 5.7mm e 0.1mm para a Mangifera indica; 4.5mm e 0.2mm para a Licania tomentosa; e, 3.8mm e 0.3mm para a Tabebuia ochracea. O retardo mediano no início das chuvas ocasionado pelas espécies arbóreas foi de 3min. A presença dos indivíduos arbóreos propiciou, um atraso mediano no tempo ao pico de 3 minutos, uma redução do pico de vazão de 0.8 mm/min e do escoamento superficial de 4.7mm/min. Através de simulações, com o cenário em que o planejamento urbano arborizado agregava todas as técnicas de LID neste estudo empregadas, conseguiu-se atingir a redução das vazões de pico em 3.42m³/s, em relação ao projeto convencional; permitindo o armazenamento de um volume de água de 4470.59m³ nas estruturas de infiltração locais propostas; e, retardar os picos de vazão em até 6 min. Esta tese, confirma a interferência das características individuais das espécies na capacidade de interceptação de chuva por suas copas e na redução do escoamento superficial, ressaltando a necessidade de definição criteriosa das espécies que comporão a arborização urbana; atesta a existência de variações nas interceptações em relação aos eventos chuvosos e durante suas ocorrências; bem como, aponta dados quantitativos de redução de volume precipitado e escoado pela presença do indivíduo arbóreo no meio urbano. A pesquisa comprovou que, isoladamente, a arborização e as técnicas de LID causam pouca redução no volume e vazão e, pouco retardo no tempo ao pico do escoamento, enquanto que somadas contribuem de forma significativa à drenagem. O presente estudo se difere pela utilização de pluviógrafos e linígrados para a aferição de precipitações e escoamento superficial diretamente sob as copas de indivíduos arbóreos em ambiente urbano; e, agrega ao SWMM a inserção dos benefícios arbóreos na simulação hidrológica.
156

Community Water and Sanitation Alternatives in Peri-Urban Cochabamba: Progressive Politics or Neoliberal Utopia?

West, Madeline January 2014 (has links)
This thesis is about the tensions faced by communitarian water service providers in peri-urban Cochabamba, Bolivia, in their continued dependence on private water vending businesses, despite efforts to socialize service delivery. Based on fieldwork conducted in Cochabamba from May-July, 2013, this thesis argues that due in part to a lack of government intervention and regulation, many communitarian water associations in Cochabamba are being held captive by private water vendors who exploit the city’s unequal distribution of water resources for profit. It makes this argument by exploring two main points: that communitarian water associations leverage progressive forms of organization to improve service delivery, but are hindered by barriers which lie outside their control; and that small-scale water businesses are able to exploit the failures of the formal state/public and informal communitarian systems by positioning themselves as a necessary operation, in a way which limits the state’s ability to regulate their activities.
157

EVALUATING POTENTIAL FOR FLOATING SOLAR INSTALLATIONS ON ARIZONA WATER MANAGEMENT INFRASTRUCTURE

Hartzell, Tynan Scott January 2016 (has links)
Sustainable Built Environments Senior Capstone Project / This capstone project evaluates the current state of floating solar photovoltaic technology and proposes use of the technology on water management infrastructure in Arizona. The study finds that floating solar photovoltaic has a higher energy density (100 W/m^2) than land-based, utility-scale solar and does not involve significant cost increases. The study proposes and models a small pilot installation on Lake Pleasant Reservoir, part of the Central Arizona Project, and finds that lifetime costs per unit energy are higher than what the Central Arizona Project currently pays for energy, assuming US median per-wattinstalled costs for commercial solar. This cost however does not factor in savings from water conservation, existing infrastructure, reduced land costs, or other benefits. The study recommends water reservoirs by hydropower dams as ideal locations for floating photovoltaic installations. Justified with a significant background on Arizona’s environmental, social, and economic sustainability, as well as regulations calling for increased renewable energy generation and reduced carbon emissions, this study recommends aggressive implementation of floating solar photovoltaic technology within a sustainable development paradigm.
158

Evaluation of the effects of an orange-oil based soil ameliorant on soil water management

Wright, Nordely 03 1900 (has links)
Thesis (MScAgric)--Stellenbosch University, 2013. / ENGLISH ABSTRACT: Soil amelioration and conditioning is desirable and in many cases essential, due to increasing food demand and the deterioration and exhaustion of soils. A new soil ameliorant, consisting of orange oil as a base and a mixture of surfactants, is on the global agricultural market. Use of this soil ameliorant by farmers has made an impact on crop production and plant growth on many farms. The effects of this soil ameliorant on selected soil properties as well as plant traits were evaluated by a field trial, a pot trial and a Water Characteristic Curve experiment. A field trial was performed in the Firgrove area near Somerset West, Western Cape (South Africa). It entailed the evaluation of the water content and lateral movement of water in a sandy soil after the application of the soil ameliorant. The field was already planted with Capsicum annuum crop at the initiation of the trial. The trial was performed in a drip irrigated field by taking soil water measurements using a Diviner 2000 probe over a nine week period. The trial showed significant increases in water content on the plots treated with the soil ameliorant. These increases are indicative of an increase in the lateral movement of the soil water, as the measurements were taken between two drippers. On average, the ameliorant treated soil had 17% higher water content than that of the control. A Water Characteristic Curve (WCC) experiment was conducted, which entailed establishing the WCC for a sandy soil treated with the soil ameliorant. The Sandbox apparatus, from Eijkelkamp Agrisearch Equipment, was used to perform the experiment and provides suction values of 0.1 to 10.1 KPa. The WCC showed that the ameliorant application increased water retention over all suctions, especially for the 10 l/ha ameliorant application. This substantiated the Field trial where water retention was increase in a sandy soil. A pot trial was performed in a greenhouse to evaluate the effect of the soil ameliorant on selected soil properties and certain plant traits. This experiment consisted of an ameliorant treatment and a control with a combination of four different Plant Available Water Depletion (PAWD) regimes namely, 10% depletion, 50% depletion, 80% depletion and 50%C depletion, where “C” refers to covered. The trial layout, with five single pot replicates per treatment combination, was according to a randomized block design. The surface covering of one of the 50% PAWDs was a plastic sheet which to prevent evaporation from the soil surface. The ameliorant treatment resulted in significant improvements in overall plant growth, total biomass production, especially dry root biomass. Leaf Area Index and plant height were also improved. The Biomass Water Use Efficiency was improved with the ameliorant application, especially for the 50%C PAWD illustrating the beneficial use of a mulch. Bulk density was decreased with application of the ameliorant but this difference was not statistically significant. Aggregate stability for the moist soils (10% and 50%C PAWD) was significantly improved with the ameliorant application. The application of this soil ameliorant made significant improvements in various facets of plant growth and certain soil physical properties. Especially water holding capacity in sandy soils and the overall improvement in plant growth. There is still much opportunity for research in this field and many questions remain, especially those pertaining to the mechanisms involved in the workings of a soil ameliorant containing a mixture of ingredients. / AFRIKAANSE OPSOMMING: Die bestuur van besproeingswater en die optimisasie van gewasproduksie is `n studieveld wat baie aandag verg, aangesien varswater bronne bedreig word. As gevolg van die stygende vraag na voedsel en die agteruitgang en uitputting van die grond, is grondverbetering en-kondisionering aanbeveelbaar en in sommige gevalle noodsaaklik. `n Nuwe grond verbeteraar, bestaande uit lemoen olie as `n basis en ‘n mengsel van benattingsmiddels, is beskikbaar op die wêreld landbou mark. Die gebruik van die grondverbeteraar deur boere het ‘n impak gemaak op gewasproduksie en plantegroei op baie plase. Die effek van die grondverbeteraar op geselekteerde grond-eienskappe sowel as plantkenmerke is geevalueer deur ‘n veld proef, ‘n pot proef en ‘n Water Karakeristieke Kurwe eksperiment. `n Veldproef is uitgevoer in die Firgrove omgewing naby Somerset Wes in die Wes-Kaap Provinsie, Suid Afrika. Die veldproef het die evaluasie van die grondwater inhoud en die laterale beweging van water in `n sanderige grond behels. Die gewas Capsicum annuum was alreeds in die veld aangeplant voor die begin van die proef. Die proef was uitgevoer in `n drup besproeide veld deur grondwater metings wat geneem is met `n Diviner 2000 peilstif oor `n periode van nege weke. Die proewe het `n beduidende verhoging in die groundwater-inhoud getoon waar die grond met die grondverbeteraar behandel is. Die verhogings was `n aanduiding van `n toename in die laterale vloei van grond water, aangesien die lesings tussen twee druppers geneem is. Die grond, wat met die grondverbeteraar behandel is, het gemiddeld 17% hoёr groundwater-inhoud gehad as die kontrole. `n Water Karakteristieke Kurwe (WKK) eksperiment is uitgevoer, wat bestaan het uit die opstel van die WKK vir `n sanderige grond behandel met die grondverbeteraar. Die “Sandbox” apparaat van Eijkelkamp, Agrisearch Equipment is gebruik wat negatiewe druk waardes van 0.1 tot 10.1 KPa toon. Die WKK het getoon dat die toediening van die grondverbeteraar die water retensie verhoog het oor al die drukke, veral in die 10 l/ha toediening. Dit staaf die resultate van die Veld eksperiment waar water retensie verhoog is in die sanderige grond. Die pot-eksperiment is uitgevoer in `n tonnel om die effek van die grondverbeteraar op geselekteerde grond eienskappe en verskeie plant eienskappe te evalueer. Die eksperiment het bestaan uit ‘n grondverbeteraar behandeling en ‘n kontrole met ‘n kombinasie van vier verskillende plantbeskikbare wateronttrekkings naamlik, 10%, 50%, 80% onttrekking, en ‘n 50%C onttrekking, waar “C” verwys na “covered”. Die proef uiteensetting, met vyf enkel pot herhalings per behandeling kombinasie was volgens ‘n ewekansig blok uitleg. Die oppervlakte dekking van 50%C plantbeskikbare waterottrekking was `n 60 μm plastiek-vel wat verdamping vanaf die grondoppervlak verhoed het. Die grondverbeteraar behandeling het `n beduidende verbetering in algehele plantgroei, totale biomassa produksie en spesifiek droё wortel biomassa getoon. Die blaararea indeks en planthoogte het ook `n verbetering getoon. Die biomassa-watergebruiksdoeltreffendheid het verbeter met die toediening van die grondverbeteraar, spesifiek vir die 50%C plantbeskikbarewaterottrekking wat die voordele van die gebruik van oppervlakdekking illustreer. Die brutodigtheid is verminder deur die toediening van die grondverbeteraar, maar die verskil was statisties nie wesenlik nie. Agregaat-stabiliteit vir die grond met `n hoёr vogregime (10% en 50%C plantbeskikbare waterottrekking) is wesenlik verbeter met die toediening van die grondverbeteraar. Die toediening van die grondverbeteraar het wesenlike verbeteringe in verskeie plantegroei- en grondfisiese-eienskappe getoon. Spesifiek laterale beweging in sanderige grond en die verbettering van algehele plantegroei. Daar is nog baie geleenthede vir navorsing in die veld en baie vrae bly onbeantwoord, veral in verband met die meganismes met bretrekking tot die werking van die grondverbeteraar wat uit `n mengsel van bestandele bestaan.
159

Mine water geochemistry and management : two case studies and a new treatment method

Love, David 12 1900 (has links)
Thesis (MSc)--Stellenbosch University, 2003. / ENGLISH ABSTRACT: Mine water, that is all forms of water associated with and affected by mining operations is probably the largest area of concern in the environmental geology of mining. This study looks at the inter-relationship between mine water geochemistry and mine water management. The objectives of this study are: 1. To examine major geochemical processes influencing mine water; 2. To apply new national water and environmental legislation to the mining industry and discover how mine water management will be regulated; 3. To examine the approach of Integrated Catchment Management, and discover how this approach can be applied to the mining industry; 4. To conduct two case studies, where environmental geochemistry, general geochemistry and multivariate analyses are used as tools to investigate groundwater contamination problems in mining areas, and therefore suggest mine water management interventions; and 5. To, considering mine water problems discovered in the case studies, develop a newly-patented chemical treatment method for possible application in the mining industry. The changing legal framework - principally the implementation of the National Water Act (Act No 36 of 1998) and the National Environmental Management Act (Act No 107 of 1998) - is leading to the responsibilities of a mine becoming substantially clearer, and responsibilities which in the past could have been ignored until public outcry will now be difficult to escape. Two case studies are investigated. In both cases, general geochemistry and hydrogeochemistry, coupled with factor analysis are used to determine the major signatures in groundwater chemistry and the major sources of contamination. On the basis of this, management interventions are suggested. In the first case study, Sishen Iron Ore Mine of the Northern Cape, three signatures are identified in the groundwater: a clean dolomitic water signature, and a contamination signature from the mine and one from agriculture. The extent of nitrate and diesel contamination is shown to be related to agriculture, the use of explosives and to mine workshops and depots. Surface water controls may help reduce these problems. In the second case study, West Driefontein Gold Mine of the Far West Rand, two signatures are identified in the groundwater: a clean dolomitic water signature and a signature relating to contamination from the mine. Cluster analysis is used to suggest three groundwater zones, the chemistry of one being fairly clean dolomitic aquifer, the chemistry of the second affected by the mine and the chemistry of the third affected by granites. Contamination is shown to be related to mining operations, especially the slimes dams, and agriculture. Rehabilitation of dams and dumps, as well as surface water controls may help reduce these problems. Considering mine water problems discovered in the case studies, a newly-patented chemical treatment method is examined and tested for possible application in the mining industry. It is shown to be extremely effective for the removal of calcium from water, but less effective for the removal of iron and manganese. More broadly, this study shows the inter-dependence between mine water geochemistry and mine water management, and the need to be multi-disciplinary in approach. / AFRIKAANSE OPSOMMING: Mynwater, dit is aile soorte water wat geaffekteer en geassosieer word met mynbou bedrywighede, is moontlik die grootste rede tot kommer in omgewingsgeologie van mynbou. Hierdie studie stel ondersoek in na die verhouding tussen mynwater geochemie en mynwater bestuur. Die doelwitte van die studie is soos volg: 1. Om die hoof geochemiese prosesse te ondersoek wat mynwater beinvloed: 2. Om die nuwe nasionale water- en omgewingswette toe te pas op die mynboubedryf en te ondersoek hoe die bestuur van mynwater gereguleer sal word; 3. Om die benadering van Gerntegreerde Opvangs Bestuur ("Integrated Catchment Managemement") te ondersoek, en te ondersoek hoe hierdie benadering op die mynbou industrie toegepas kan word' 4. Om twee gevallestudies te doen, waar omgewingsgeochemie, algemene geochemie en multivariant analise gebruik word as middels om grondwater besoedeling in mynbougebiede te ondersoek, en daarvolgens om mynwater bestuurswysigings voor te stel; en 5. Om, nemende in ag die mynwater probleme wat ontdek is in die gevallestudies, 'n nuutgepatenteerde chemiese behandelingsmetode, vir moontlike toepassing in die mynbou industrie, te ontwikkel. Die veranderende regtelike raamwerk - hoofsaaklik die implementering van die Nasionale Waterwet (Wet No. 36 van 1998) en die Nasionale Omgewingsbestuur Wet (Wet No.1 07 van 1998) - lei daartoe dat 'n myn verantwoordelik moet wees om opmerklik skoner te word, verantwoordelikhede wat in die verlede maklik gergnoreer kon word maar wat nou te moeilik is om te ignoreer as gevolg van publieke uitroepe. Twee gevalle is ondersoek. In be ide studies word algemene geochemie en hidrogechemie, saam met faktoranalise, gebruik om die hoof kenmerke te bepaal in grondwaterchemie en die hoof bronne van besoedeling. Deur dit as basis te gebruik word bestuurswysigings voorgestel. In die eerste gevallestudie, Sishen Ystererts Myn in die Noordkaap, is drie kenmerkende samestellings qeidentitiseer in die grondwater: 'n skoon dolomitiese samestelling, en een elk van 'n myn en landbou gekontamineerde samestelling. Die omvang van nitraat en diesel kontaminasie word aangedui as geassosieerd met landbou, die gebruik van plofstowwe, mynwerkswinkels en depots. Oppervlak waterbeheer mag help om hierdie probleme te beheer. In die tweede gevallestudie, Wes Driefontein Goudmyn in die Ver Wesrand, is twee kenmerkende samestellings in die grondwater gerdentifiseer: 'n skoon dolomitiese samestelling en 'n samestelling geassosieer met kontaminasie van die myn. "Cluster" analise is gebruik om drie grondwatersones te identifiseer, die eerste een se chemie stem redelik ooreen met 'n skoon akwifer, die tweede een se chemie is bernvloed deur die myn en die derde se chernie is deur granite bemvloed. Kontaminasie word aangedui as geassosieer met mynboubedrywighede, veral die slikdamme, en landbou. Rehabilitasie van damme en afvalhope, asook oppervlak waterbeheer mag help om die probleem te verminder. Deur die mynwater probleme wat in die gevallestudies ontdek is in ag te neem, word 'n nuutgepatenteerde chemiese behandeling ondersoek en getoets vir moontlike toepassing in die mynboubedryf. Dit word aangewys as uiters effektief vir die verwydering van kalsium, maar minder effektief in die verwydering van yster en mangaan. In die algemeen, wys hierdie studie inter-afhanklikheid tussen mynwater geochemie en mynwater bestuur, en 'n behoefte aan 'n rnultidissiplinere benadering.
160

Time series models of the electrical conductivity measured at the Manchar Lake in Pakistan

Zehra, Syeda Mahe 16 November 2010 (has links)
The Manchar Lake in Pakistan is in danger. So are the native fisher folk that populate the area and lake. The lake is undergoing water quality degradation due to both a decrease in the amount of freshwater inflow and an increase in the polluted agricultural run-off. The fish in the lake are dying and some fish species are becoming extinct, the people living on and around the lake are facing severe health risks, migratory birds are no longer stopping at the Manchar Lake and agriculture in the area is also suffering. This report focuses on time-series modeling and analysis of water quality data from Manchar Lake. We evaluate data for three sites within the Manchar Lake and complete time series models and analysis for two sites. Particular attention is given to the Electrical Conductivity data of the lake. The approach to modeling and time series analysis provide an example of potential uses of measured data to recognize shifts in water quality within the context of potential insights and recommendations about lake management in the area. / text

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