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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.
241

Modelo analítico para a avaliação do escoamento de água no Aquífero Guarani em Bauru/SP / Analytical model for the groundwater flow assessment in the Guarani Aquifer in the city of Bauru/SP

Vinicius Ferreira Boico 02 June 2016 (has links)
Os eventos de escassez hídrica observados nos últimos anos e o aumento populacional no Estado de São Paulo têm conduzido à maior explotação de água subterrânea do Sistema Aquífero Guarani (SAG) para abastecimento público. Somente no município de Bauru/SP, está previsto um aumento da vazão de água extraída deste Aquífero de 3.699 m3/h (2014) para 4.465 m3/h (2034). Entretanto, a superexplotação em longo prazo do Aquífero pode comprometer a quantidade de água disponível. O Método de Elementos Analíticos foi utilizado para a modelagem do escoamento em regime permanente, considerando o escoamento regional, a extração de água por poços e os principais condicionantes geológicos locais. Observou-se que o gradiente hidráulico do SAG na cidade de Bauru é de aproximadamente 0,82 m/km. Os poços públicos que operam em regime de escoamento confinado estão localizados a nordeste da cidade. O rebaixamento esperado devido ao cenário previsto pelo DAE, em 2034, é de até 15 m com relação ao cenário atual (2014). Este rebaixamento pode ser controlado em até 5 m, reduzindo em 20% a vazão média anual de todos os poços, e em até 10 m, reduzindo em 10% a vazão média anual de todos os poços localizados na área central. A extração de água do SAG em Bauru/SP pode causar o rebaixamento de até 15 m nas cidades mais próximas (Piratininga e Agudos) e pouco interfere no escoamento de água do SAG das cidades mais distantes. Finalmente, os mapas potenciométricos e de rebaixamento gerados pelo modelo analítico são adequados para a análise do escoamento de água subterrânea e podem auxiliar no gerenciamento de recursos hídricos. / The recent drought events and the population growth in São Paulo State (Brazil) have caused many municipalities to increase the groundwater exploitation of the Guarani Aquifer System (GAS). In the city of Bauru/SP, the extraction of water from the Aquifer is expected to increase from 3,699 m3/h, in 2014, to 4,465 m3/h, by 2034. However, the long-term overexploitation of the Aquifer may compromise the amount of available water. The Analytical Element Method was used for the groundwater flow modeling in steady state. The regional flow, the water extraction by wells and the main local geological conditions were considered. The hydraulic gradient in the GAS in Bauru is approximately 0.82 m/km. The public wells in operation in confined flow regime are located in the eastern region of the city. The expected drawdown caused by the scenario predicted by the Department of Water and Wastewater of Bauru, in 2034, can reach 15 m, in comparison with the current situation (2014). Such lowering can be controlled up to 5 m, reducing 20% of the average annual groundwater flow rate of all wells, and up to 10 m, reducing 10% of the annual flow rate of all wells located in the critical area. The GAS groundwater extraction in Bauru/SP may cause the lowering of up to 15 m in nearby cities (Piratininga and Agudos) and has negligible interference in the groundwater flow in the GAS of distant cities. Finally, the potentiometric and drawdown maps generated by the analytical model are suitable for the analysis of groundwater flow and can be useful for the management of water resources.
242

Estudo in situ da fixação biológica de nitrogênio pelo fitoplâncton em reservatórios subtropicais (SP) / Study in situ of biological nitrogen fixation by phytoplankton in subtropical reservoirs (SP)

Gabriela Albino Marafão 19 May 2016 (has links)
A eutrofização artificial é um dos maiores desafios da sociedade moderna em relação à manutenção dos usos múltiplos da água, portanto, é preciso estudar os mecanismos que influenciam a variação das características bióticas e abióticas dos reservatórios em resposta às interferências antrópicas, sobretudo ao incremento excessivo de nutrientes, nitrogênio e fósforo. Estes nutrientes afetam a produção da biomassa aquática e favorecem florações de cianobactérias. Diante dessa problemática, a presente pesquisa quantificou as taxas de fixação biológica de nitrogênio pelo fitoplâncton, considerando que algumas cianobactérias se beneficiam dessa habilidade competitiva para dominarem muitos ecossistemas aquáticos. Para isso, foram estudados três reservatórios subtropicais com diferentes graus de trofia no estado de São Paulo, totalizando oito amostragens entre 2013 e 2015. Além de variáveis abióticas e bióticas da água, foram utilizados dois métodos, um indireto e outro direto, para estimar as taxas de fixação: redução do acetileno e traçador isótopo 15N2. Os reservatórios de Itupararanga, Barra Bonita e Lobo foram classificados como eutrófico, hipereutrófico e supereutrófico, respectivamente. As maiores concentrações de nutrientes (nitrogênio total Kjeldahl: 5.930 µg /L e fósforo total: 466 µg /L ) foram observadas no reservatório de Barra Bonita, no qual não foi detectada fixação significativa pela predominância de Microcystis aeruginosa, não fixadora de N2, que atingiu biovolume máximo de 110 mm3/L. Em Itupararanga, nas coletas de outubro de 2013 e fevereiro de 2014, Cylindrospermopsis raciborskii e Anabaena sp. foram responsáveis pelas taxas de fixação, sendo que essa última apresentou maior frequência de heterócitos (75%). No Lobo, Aphanizomenon sp. (durante o inverno), C. raciborskii (durante o verão) e Lyngbya sp. (fixadora noturna de N2) realizaram a fixação em todas as amostragens, com exceção de fevereiro de 2014. Nos reservatórios de Itupararanga e no Lobo, mesmo em condições de excesso de nutrientes e elevadas relações N:P (máximo de 564:1), as taxas de fixação atingiram 0,22 e 0,95 µg/L.h, que são consideradas elevadas quando comparadas a outros estudos em ambientes temperados. A comparação entre as metodologias sugeriu que o método direto, com o traçador 15N2, foi mais sensível que o indireto, da redução do acetileno. Entre as variáveis analisadas, a que mais influenciou a fixação foi a estrutura da comunidade fitoplanctônica (e.g., características qualitativas, capacidade de fixação e presença de heterócito). As variáveis climatológicas (precipitação e temperatura) e hidrológica (tempo de detenção hidráulico), juntamente com a disponibilidade de nutrientes e a possível competição entre espécies e grupos fitoplanctônicos, regularam a comunidade fitoplanctônica. A análise do processo de fixação no período diurno ou noturno permitiu inferir diferentes estratégias adaptativas das cianobactérias presentes nos ambientes estudados. Para os três reservatórios analisados, concluiu-se que a qualidade da água está comprometida devido à floração de cianobactérias potencialmente tóxicas e isso evidencia a necessidade de medidas de controle de estado trófico para garantir os usos múltiplos da água e a saúde pública. O processo de fixação pode representar uma parcela significativa de nitrogênio nos sistemas aquáticos e não foi inibido pelo excesso de nutrientes. / Artificial eutrophication is one of the greatest challenges of modern society in relation to the maintenance of the multiple uses of water, therefore it is necessary to study the mechanisms that influence the variation of biotic and abiotic characteristics of the reservoirs in response to anthropogenic interference, especially the increase of nutrients, nitrogen and phosphorus. Such nutrients affect the production of aquatic biomass and favor cyanobacteria. This research quantified the biological nitrogen fixation rates by the phytoplankton, considering that some cyanobacteria benefit from this competitive ability to dominate many Brazilian aquatic ecosystems. We studied three subtropical reservoirs with different trophic levels in the São Paulo State, Brazil, performing eight sampling campaigns between 2013 and 2015. In addition to the abiotic and biotic variables of water, two methods were used to estimate the fixation rates: acetylene reduction and tracer isotope 15N2. The reservoirs Itupararanga, Barra Bonita and Lobo were classified as eutrophic, hypertrophic and supereutrophic, respectively. The highest concentrations of nutrients (Total Kjeldahl Nitrogen: 5.930 µg/L and total phosphorus = 466 µg/L) were observed in the Barra Bonita Reservoir, where no fixation was detected due to the predominance of Microcystis aeruginosa, non-fixing cyanobacteria, with a maximum biovolume of 110 mm3/L. In Itupararanga, in October 2013 and January 2014, Cylindrospermopsis raciborskii and Anabaena sp. were responsible for nitrogen fixation, the latter with greater frequency of heterocysts (75%). In Lobo, Aphanizomenon sp. (during the winter), C. raciborskii (during the summer) and Lyngbya sp. (night fixing N2) fixation was detected in all samplings, except for February 2014. In the Itupararanga and Lobo Reservoirs, even with excess of nutrients and at high N:P ratios (maximum of 564:1), the fixation rates reached 0.22 and 0.95 µg/L.h, which were high when compared to temperate environments. The comparison between the methodos indicated that the direct method, through the tracer 15N2, was more sensitive than the indirect method of the acetylene reduction. Considering the analyzed variables, phytoplankton community structure significantly influenced the nitrogen fixation (e.g., qualitative aspects, N2 fixation capacity and presence of heterocysts). The climatological (precipitation and temperature) and hydrological (hydraulic retention time) variables, associated with the availability of nutrients and competition among species and phytoplankton groups, regulated the phytoplankton community in the reservoirs. The analysis of the nitrogen fixation during day or night periods allowed inferring different adaptive strategies of cyanobacteria. For the three reservoirs analyzed, it is concluded that the water quality is impaired due to the bloom of potentially toxic cyanobacteria and this highlights the need for trophic state control measures to ensure the multiple uses of water and public health. The fixation process can represent a significant part of nitrogen in aquatic systems and was not inhibited by excess nutrients.
243

Análise do processo participativo na gestão dos recursos hídricos no Estado de São Paulo: um estudo de caso do Comitê da Bacia Hidrográfica do Tietê - Jacaré / Analise of the partipative process in the water resources management in the São Paulo State: a case study of Tiete Jacare Watershed Commitee

Prota, Mariza Guimarães 18 October 2011 (has links)
O modelo atual de gestão dos recursos hídricos no Brasil é descentralizado, participativo e integrado, e tem como unidade de planejamento a bacia hidrográfica. Baseia-se na atuação de comitês de bacia, sendo que cada comitê possui composição e regras de funcionamento próprias, regidas por seu estatuto. Os princípios básicos desta gestão foram ditados pela Constituição Brasileira de 1988 e detalhados pela Política Nacional de Recursos Hídricos, instituída por meio da Lei Federal nº 9433/97. Porém, já em 1991, São Paulo promulgou sua Política Estadual de Recursos Hídricos, através da Lei Estadual nº 7663/91, que também prevê a implementação de instrumentos de gestão. Atualmente, decorridos quase 20 anos da promulgação da lei estadual, críticas são feitas a este modelo de gestão. Esta pesquisa analisou o processo de participação nos comitês de bacia do Estado de São Paulo por meio de um estudo de caso no Comitê da Bacia Hidrográfica do Tietê Jacaré, adotando como metodologia a aplicação de questionários aos seus membros da gestão 2009 - 2011. Os resultados encontrados, além de apontar para a necessidade de revisão do estatuto deste comitê, evidenciaram as distorções causadas pelas divergências entre a legislação estadual e a federal, principalmente quanto aos segmentos participantes e atores envolvidos. Mostraram também a necessidade de uma maior divulgação das questões de recursos hídricos nesta bacia e no Estado de São Paulo, como um todo / The current model of water resources management in Brazil is decentralized, participative and integrated, and adopted the river basin as a planning unit. Its based on the performance of basin committees; each Committee has its own composition and rules of procedure, governed by its statute. The basic principles of this management have been established by the Brazilian Constitution of 1988 and detailed by the National Water Resources Policy, established by Federal Law nº. 9433/97. However, already in 1991, São Paulo State promulgated its Water Resources Policy, through State Law nº. 7663/91, which also provides for the implementation of management instruments. Nowadays, after almost 20 years of the enactment of State law, comments about this water resources management model have been made. This research examined the participatory process in basin committees of the São Paulo State through a case study in the Tiete - Jacare Basin Committee, based on the application of questionnaires to the Committees members. The interviews results have pointed that the Committees statute need to be reviewed, and showed the differences between the Federal and the State legislations, mainly regarding the participating sectors and representatives involved. They also showed that a greater disclosure of water resource issues in this basin and in the State of São Paulo, as a whole, is necessary
244

Modelo analítico para a avaliação do escoamento de água no Aquífero Guarani em Bauru/SP / Analytical model for the groundwater flow assessment in the Guarani Aquifer in the city of Bauru/SP

Boico, Vinicius Ferreira 02 June 2016 (has links)
Os eventos de escassez hídrica observados nos últimos anos e o aumento populacional no Estado de São Paulo têm conduzido à maior explotação de água subterrânea do Sistema Aquífero Guarani (SAG) para abastecimento público. Somente no município de Bauru/SP, está previsto um aumento da vazão de água extraída deste Aquífero de 3.699 m3/h (2014) para 4.465 m3/h (2034). Entretanto, a superexplotação em longo prazo do Aquífero pode comprometer a quantidade de água disponível. O Método de Elementos Analíticos foi utilizado para a modelagem do escoamento em regime permanente, considerando o escoamento regional, a extração de água por poços e os principais condicionantes geológicos locais. Observou-se que o gradiente hidráulico do SAG na cidade de Bauru é de aproximadamente 0,82 m/km. Os poços públicos que operam em regime de escoamento confinado estão localizados a nordeste da cidade. O rebaixamento esperado devido ao cenário previsto pelo DAE, em 2034, é de até 15 m com relação ao cenário atual (2014). Este rebaixamento pode ser controlado em até 5 m, reduzindo em 20% a vazão média anual de todos os poços, e em até 10 m, reduzindo em 10% a vazão média anual de todos os poços localizados na área central. A extração de água do SAG em Bauru/SP pode causar o rebaixamento de até 15 m nas cidades mais próximas (Piratininga e Agudos) e pouco interfere no escoamento de água do SAG das cidades mais distantes. Finalmente, os mapas potenciométricos e de rebaixamento gerados pelo modelo analítico são adequados para a análise do escoamento de água subterrânea e podem auxiliar no gerenciamento de recursos hídricos. / The recent drought events and the population growth in São Paulo State (Brazil) have caused many municipalities to increase the groundwater exploitation of the Guarani Aquifer System (GAS). In the city of Bauru/SP, the extraction of water from the Aquifer is expected to increase from 3,699 m3/h, in 2014, to 4,465 m3/h, by 2034. However, the long-term overexploitation of the Aquifer may compromise the amount of available water. The Analytical Element Method was used for the groundwater flow modeling in steady state. The regional flow, the water extraction by wells and the main local geological conditions were considered. The hydraulic gradient in the GAS in Bauru is approximately 0.82 m/km. The public wells in operation in confined flow regime are located in the eastern region of the city. The expected drawdown caused by the scenario predicted by the Department of Water and Wastewater of Bauru, in 2034, can reach 15 m, in comparison with the current situation (2014). Such lowering can be controlled up to 5 m, reducing 20% of the average annual groundwater flow rate of all wells, and up to 10 m, reducing 10% of the annual flow rate of all wells located in the critical area. The GAS groundwater extraction in Bauru/SP may cause the lowering of up to 15 m in nearby cities (Piratininga and Agudos) and has negligible interference in the groundwater flow in the GAS of distant cities. Finally, the potentiometric and drawdown maps generated by the analytical model are suitable for the analysis of groundwater flow and can be useful for the management of water resources.
245

Estudo in situ da fixação biológica de nitrogênio pelo fitoplâncton em reservatórios subtropicais (SP) / Study in situ of biological nitrogen fixation by phytoplankton in subtropical reservoirs (SP)

Marafão, Gabriela Albino 19 May 2016 (has links)
A eutrofização artificial é um dos maiores desafios da sociedade moderna em relação à manutenção dos usos múltiplos da água, portanto, é preciso estudar os mecanismos que influenciam a variação das características bióticas e abióticas dos reservatórios em resposta às interferências antrópicas, sobretudo ao incremento excessivo de nutrientes, nitrogênio e fósforo. Estes nutrientes afetam a produção da biomassa aquática e favorecem florações de cianobactérias. Diante dessa problemática, a presente pesquisa quantificou as taxas de fixação biológica de nitrogênio pelo fitoplâncton, considerando que algumas cianobactérias se beneficiam dessa habilidade competitiva para dominarem muitos ecossistemas aquáticos. Para isso, foram estudados três reservatórios subtropicais com diferentes graus de trofia no estado de São Paulo, totalizando oito amostragens entre 2013 e 2015. Além de variáveis abióticas e bióticas da água, foram utilizados dois métodos, um indireto e outro direto, para estimar as taxas de fixação: redução do acetileno e traçador isótopo 15N2. Os reservatórios de Itupararanga, Barra Bonita e Lobo foram classificados como eutrófico, hipereutrófico e supereutrófico, respectivamente. As maiores concentrações de nutrientes (nitrogênio total Kjeldahl: 5.930 µg /L e fósforo total: 466 µg /L ) foram observadas no reservatório de Barra Bonita, no qual não foi detectada fixação significativa pela predominância de Microcystis aeruginosa, não fixadora de N2, que atingiu biovolume máximo de 110 mm3/L. Em Itupararanga, nas coletas de outubro de 2013 e fevereiro de 2014, Cylindrospermopsis raciborskii e Anabaena sp. foram responsáveis pelas taxas de fixação, sendo que essa última apresentou maior frequência de heterócitos (75%). No Lobo, Aphanizomenon sp. (durante o inverno), C. raciborskii (durante o verão) e Lyngbya sp. (fixadora noturna de N2) realizaram a fixação em todas as amostragens, com exceção de fevereiro de 2014. Nos reservatórios de Itupararanga e no Lobo, mesmo em condições de excesso de nutrientes e elevadas relações N:P (máximo de 564:1), as taxas de fixação atingiram 0,22 e 0,95 µg/L.h, que são consideradas elevadas quando comparadas a outros estudos em ambientes temperados. A comparação entre as metodologias sugeriu que o método direto, com o traçador 15N2, foi mais sensível que o indireto, da redução do acetileno. Entre as variáveis analisadas, a que mais influenciou a fixação foi a estrutura da comunidade fitoplanctônica (e.g., características qualitativas, capacidade de fixação e presença de heterócito). As variáveis climatológicas (precipitação e temperatura) e hidrológica (tempo de detenção hidráulico), juntamente com a disponibilidade de nutrientes e a possível competição entre espécies e grupos fitoplanctônicos, regularam a comunidade fitoplanctônica. A análise do processo de fixação no período diurno ou noturno permitiu inferir diferentes estratégias adaptativas das cianobactérias presentes nos ambientes estudados. Para os três reservatórios analisados, concluiu-se que a qualidade da água está comprometida devido à floração de cianobactérias potencialmente tóxicas e isso evidencia a necessidade de medidas de controle de estado trófico para garantir os usos múltiplos da água e a saúde pública. O processo de fixação pode representar uma parcela significativa de nitrogênio nos sistemas aquáticos e não foi inibido pelo excesso de nutrientes. / Artificial eutrophication is one of the greatest challenges of modern society in relation to the maintenance of the multiple uses of water, therefore it is necessary to study the mechanisms that influence the variation of biotic and abiotic characteristics of the reservoirs in response to anthropogenic interference, especially the increase of nutrients, nitrogen and phosphorus. Such nutrients affect the production of aquatic biomass and favor cyanobacteria. This research quantified the biological nitrogen fixation rates by the phytoplankton, considering that some cyanobacteria benefit from this competitive ability to dominate many Brazilian aquatic ecosystems. We studied three subtropical reservoirs with different trophic levels in the São Paulo State, Brazil, performing eight sampling campaigns between 2013 and 2015. In addition to the abiotic and biotic variables of water, two methods were used to estimate the fixation rates: acetylene reduction and tracer isotope 15N2. The reservoirs Itupararanga, Barra Bonita and Lobo were classified as eutrophic, hypertrophic and supereutrophic, respectively. The highest concentrations of nutrients (Total Kjeldahl Nitrogen: 5.930 µg/L and total phosphorus = 466 µg/L) were observed in the Barra Bonita Reservoir, where no fixation was detected due to the predominance of Microcystis aeruginosa, non-fixing cyanobacteria, with a maximum biovolume of 110 mm3/L. In Itupararanga, in October 2013 and January 2014, Cylindrospermopsis raciborskii and Anabaena sp. were responsible for nitrogen fixation, the latter with greater frequency of heterocysts (75%). In Lobo, Aphanizomenon sp. (during the winter), C. raciborskii (during the summer) and Lyngbya sp. (night fixing N2) fixation was detected in all samplings, except for February 2014. In the Itupararanga and Lobo Reservoirs, even with excess of nutrients and at high N:P ratios (maximum of 564:1), the fixation rates reached 0.22 and 0.95 µg/L.h, which were high when compared to temperate environments. The comparison between the methodos indicated that the direct method, through the tracer 15N2, was more sensitive than the indirect method of the acetylene reduction. Considering the analyzed variables, phytoplankton community structure significantly influenced the nitrogen fixation (e.g., qualitative aspects, N2 fixation capacity and presence of heterocysts). The climatological (precipitation and temperature) and hydrological (hydraulic retention time) variables, associated with the availability of nutrients and competition among species and phytoplankton groups, regulated the phytoplankton community in the reservoirs. The analysis of the nitrogen fixation during day or night periods allowed inferring different adaptive strategies of cyanobacteria. For the three reservoirs analyzed, it is concluded that the water quality is impaired due to the bloom of potentially toxic cyanobacteria and this highlights the need for trophic state control measures to ensure the multiple uses of water and public health. The fixation process can represent a significant part of nitrogen in aquatic systems and was not inhibited by excess nutrients.
246

From water resources management to integrated water resources management : an analysis of the establishment of new water management organisations in Namibia

Simataa, Faith Auguste January 2010 (has links)
<p>The questions posed in this study address the different processes that were involved in the decision-making and establishment of the water management organisations, the extent of public participation, as well as features of evident governance in implementing the policies. A critical analysis of the role of stakeholders and the various influences they may have in water management will also be examined. The methodology follows a historical study approach. A thorough document review will be done of the policies and related materials around BMCs, where events will be constructed from the findings. Interviews will be conducted for verification purposes, to verify the desktop findings and to assimilate any conflicts of opinion that might have not been documented.</p>
247

From water resources management to integrated water resources management : an analysis of the establishment of new water management organisations in Namibia

Simataa, Faith Auguste January 2010 (has links)
<p>The questions posed in this study address the different processes that were involved in the decision-making and establishment of the water management organisations, the extent of public participation, as well as features of evident governance in implementing the policies. A critical analysis of the role of stakeholders and the various influences they may have in water management will also be examined. The methodology follows a historical study approach. A thorough document review will be done of the policies and related materials around BMCs, where events will be constructed from the findings. Interviews will be conducted for verification purposes, to verify the desktop findings and to assimilate any conflicts of opinion that might have not been documented.</p>
248

Institutional overlaps in water management in the Eerste River Catchment.

Nleya, Ndodana January 2005 (has links)
In this minithesis I have investigated overlapping mandates as a source of management failure in water management in South Africa in general and Eerste River Catchment in particular. I analysed major legislation which deals with water management to find out how duties and responsibilities are apportioned in the various pieces of legislation. I also undertook an exercise of evaluating roles and responsibilities played by various organs of state in water management from national government, Provincial Government of the Western Cape through to local government, in this case the Municipality of Stellenbosch and the City of Cape Town. It emerged that there were a number of areas of overlap, ambiguously defined mandates, conflict and that these were impeding on decision making in water management. In order to test the framework built above, I then applied it in the Plankenbrug River, a tributary of the Eerste River. Through analysis of newspaper clippings over a period of 4 years I was able to reconstruct conflict over ill-defined mandates in the various aspects of the management of the catchment which showed that<br /> there were differences in roles of the different state organs operating in the catchment. Water management conflict emanated from lack of congruence in the various legislation and differences in the interpretation of legislation. The various state organs seem to be aware of the constitutional duty of cooperative government that engenders state organs to work co-operatively in order to meet their developmental mandates. It seems however that the state organs were merely interested to be seen to be in conformity with this duty more than actually solving the issue as this was seen as something to be tackled at a higher level.
249

Desempenho de redes neurais artificiais e árvores de regressão na modelagem do processo chuva-vazão da bacia do Alto Canoas / Performance of artificial neural networks and regression trees in the rainfall-runoff modeling in the basin Alto Canoas process

Debastiani, Aline Bernarda 15 February 2016 (has links)
Submitted by Claudia Rocha (claudia.rocha@udesc.br) on 2017-12-07T12:49:04Z No. of bitstreams: 1 PGEF16MA053.pdf: 1576798 bytes, checksum: 649706432937dc5a8116984a2bb20aa7 (MD5) / Made available in DSpace on 2017-12-07T12:49:04Z (GMT). No. of bitstreams: 1 PGEF16MA053.pdf: 1576798 bytes, checksum: 649706432937dc5a8116984a2bb20aa7 (MD5) Previous issue date: 2016-02-15 / FAPESC / The future behavior estimate of minimum, medium and maximum discharges of a watershed is essential to elaborate themanagement plan of its water resources.There are two modelling approaches to generate predictions series: models that consider the physical processes occurring in the basin and data-oriented models.This work aims to evaluate dataoriented models, among which the most popular are the Artificial Neural Networks (ANN). The Regression Trees (RT) also have great potential for this kind of application, but they are not so widespread in Hydrology, which is why they were included in this work. These models were evaluated in the Upper Canoas basin, whose outlet coincides with Rio Bonito Station. In the first chapter, the objective was to evaluate the performance of an ANN method called Multi Layer Perceptron (MLP) in closed-loop mode to estimate daily discharge, considering different input vectors in order to assess the most appropriate combinations. The input vectors data series were composed of observed precipitation, evapotranspiration and discharge of the previous day. The training was held in open-loop mode, where all model input treatments were constituted of observed flow rate of the previous day (t-1) among other variables. To simulate the flow in the test period was the MLP used for open-loop and closed-loop mode, the latter being composed of a simulated flow of entries in t-1. The combination of input vectors with the best performance constituted of daily rainfall of the four rainfall stations, rainfall with t-2 days delay of the same four stations and discharge with t-1 day delay. The second chapter presents an evaluation of modeling performance in the monthly scale comparing some RTs (M5P, REP Tree and Decision Stump) and the MLP ANN. The experiment was set up with one period for training and two periods for testing. Among the RTs, the M5P produced the best results. In one of the test periods, M5P presented similar performance to the MLP, being considered an interesting alternative to using ANNs / A estimativa do comportamento futuro das vazões mínimas, médias e máximas de uma bacia hidrográfica é fundamental para a elaboração do plano de gerenciamento dos seus recursos hídricos. Existem duas abordagens de modelos que possibilitam gerar séries de previsões: a abordagem dos modelos baseados nos processos físicos que ocorrem na bacia e a abordagem dos modelos orientados a dados. Esta dissertação se propõe a avaliar modelos orientados a dados, dentre os quais, os mais populares são as Redes Neurais Artificiais (RNAs). As Árvores de Regressão (RT) também apresentam grande potencial de aplicação, embora pouco difundidas na Hidrologia, motivo pelo qual estão incluídas neste trabalho. Estes modelos foram avaliados na bacia hidrográfica do Alto Canoas, cujo exutório coincide com a Estação Rio Bonito. No capitulo 1, o objetivo foi avaliar o desempenho de uma RNA do tipo Multi Layer Perceptron (MLP), em modo closed-loop, tratandose diferentes combinações de vetores de entrada, visando determinar o mais adequado para estimar as vazões diárias. Os vetores de entrada foram constituídos de séries observadas de precipitação, evapotranspiração e da vazão do dia anterior. O treinamento foi realizado em modo open-loop, em que todos os tratamentos de entrada do modelo foram constituídos pela vazão observada do dia anterior (t-1) entre outras. Para a simulação da vazão no período de teste foi utilizada a MLP em modo open-loop e closed-loop, sendo a última composta por uma das entradas a vazão simulada em t-1. A combinação de vetores de entrada que apresentou melhor desempenho foi constituído pelo registro da precipitação diária nas quatro estações pluviométricas, precipitação com atraso de t-2 dias para as mesmas quatro estações e vazão em t-1. O capitulo 2 apresenta a avaliação do desempenho, na escala mensal, de algumas RTs (M5P, REP Tree e Decision Stump) frente ao desempenho de uma RNA do tipo MLP. O experimento foi configurado com um período para treinamento e dois períodos para teste. Entre as RTs, a M5P produziu os melhores resultados. Em um dos períodos de teste, a M5P apresentou desempenho semelhante ao da MLP, sendo considerada uma alternativa interessante ao uso de RNAs
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Transdisciplinarity as a means for capacity development in water resources management / Transdisziplinarität als Instrument für capacity development in der Wasserbewirtschaftung

Leidel, Marco 12 June 2018 (has links) (PDF)
Water resources management has to deal with complex real life problems under uncertain framework conditions. One possibility for encountering such challenges is integrated water resources management (IWRM). However, IWRM is often understood as prescriptive manual, not acknowledging the need for adaptive solutions and capacity development (CD). These challenges demonstrate that sustainable water resources management requires transdisciplinarity, i.e. the integration of several scientific disciplines, as well as the collaboration between science and local actors. Transdisciplinarity is inherently related to CD since it facilitates collaboration and provides mutual learning and knowledge on complex interrelationships. This correlates with the evidence that CD can be seen as a key factor for water resources management (Alaerts et al. 1991, Alaerts 2009). Consequently, the objective of this thesis is to strengthen water resources management by connecting processes of IWRM and CD in a transdisciplinary sense, i.e. (i) interrelating disciplinary research within an interdisciplinary research team that collaborates with local actors, and (ii) conducting a political process for knowledge and capacity development. Based on general insights, an embedded case study in the Western Bug River Basin, Ukraine, was conducted to evaluate the concept. It is shown that CD is essential for shifting from IWRM theories towards implementation and accordingly advantages of harmonizing CD into the IWRM process are presented (Leidel et al. 2012). Next to capacity issues, also other coordination gaps were assessed. River Basin Organisations are frequently proposed as a response to the administrative gap; however, coordination efforts cannot be simply reduced by transferring tasks from jurisdictional institutions to a river basin authority, because they will always need to coordinate with organizations from within or outside the water sector (von Keitz and Kessler 2008). Thus, coordination mechanisms across the boundaries of relevant policy fields are essential. Therefore, a management framework is established linking technical development and capacity development that describes interrelations between environmental pressures and capacity and information gaps for different levels of water management (Leidel et al. 2014). The developed model-based and capacity-based IWRM framework combines model-based systems analysis and capacity analysis for developing management options that support water management actors. This is aligned with a political process for capacity development. It constitutes a boundary object for approaching cross-scale challenges that converges analyses, assessments and participation into one strategy. As concluded by Mollinga (2008), this can improve the performance of sustainable resources management by approaching transdisciplinarity. Within the model and capacity-based IWRM framework, the results of the integrated analysis are made explicit and transparent by introducing a matrix approach. Technical issues, institutional challenges, organizational and human resources development, and information needs are jointly assessed and interrelated by confronting pressures and coordination gaps on a subsystem basis. Accordingly, the concept supports a transparent decision making process by identifying knowledge and capacities required for the implementation of technical intervention options and vice versa. The method is applied in the International Water Research Alliance Saxony (IWAS) model region ‘Ukraine’. It could be shown that the approach delivers management options that are scientifically credible and also accepted by and relevant for the actors. The case study revealed that technical intervention measures for the urban and rural water management have to be jointly implemented with appropriate CD measures and an accompanying political process on (i) strengthening the institutional framework and interministerial collaboration, (ii) fitting RBM into the existing institutional framework, (iii) setting up prerequisites for realistic RBM (Monitoring, information management, legal enforcement), (iv) a revision of effluent standards and a differentiated levy system, (v) cost covering tariffs, (vi) association work. For the Western Bug River Basin (WBRB), the strengthening of the collaboration between actors on all levels has to be continued. For increasing the usability, the approach needs to be institutionalized and become more practice relevant, e.g. by extending it to a water knowledge management system. Developing a roadmap for establishing transboundary water management is a subsequent step. For strengthening future water management actors, IWRM curricula development at uni-versities in Ukraine was supported. And we developed the e-learning module IWRM-education that links interactively different aspects of water management to comprehend the complexity of IWRM (Leidel et al. 2013). The evaluation showed that participants under-stand the content, appreciate this way of learning, and will use this module for further activities. The case study showed that technical cooperation can be a facilitator for political processes and that it can support decision making in a transparent way. Yet, it also showed that IWRM is highly political process and that the developed approach cannot cover all obstacles. In summary, exploring and reducing simultaneously environmental pressures and capacity and information gaps is essential for water sector evolution worldwide. Accordingly, transdisciplinarity as a means for capacity development can support the implementation of real integrated water resources management.

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