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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.
51

Uso de aguapé (Eichhornia crassipes) em sistema de tratamento de efluente de matadouro e frigorífico e avaliação de sua compostagem

Mees, Juliana Bortoli Rodrigues 27 March 2006 (has links)
Made available in DSpace on 2017-05-12T14:48:07Z (GMT). No. of bitstreams: 1 Juliana Bortoli Rodrigues Mees.pdf: 2709034 bytes, checksum: 02264027f5193bac921eb872df0081a9 (MD5) Previous issue date: 2006-03-27 / The objective of the recent research was to evaluate the water hyacinth performance (E. crassipes), applied in situ in a slaughter house treatment system, located in the west of the Paraná state, observing the nutrients removal (nitrogen composts and total phosphorus), organic matter (COD and BOD), turbidity and suspended solids, obtaining as well data from the production, management and composting practices of the biomass generated in the system. The plants were introduced into the forth tank of the industry stabilization lagoons system, covering 35m2 of the total area delimitated for the experiment: 870m2. During a period of 11 months (47 weeks) of water hyacinth development, physic and chemical parameters were monitored monthly and meteorological parameters were monitored daily or weekly. In order to search information about the degradation of the water hyacinths removed from the treatment, another experiment was conduced in plant pilot. Eight composting piles were built measuring approximately 0.60m3, with four distinct treatments that were done twice. The treatments were T1 - Water hyacinth (E. crassipes), T2 - Water hyacinth and swine excrement (7:1), T3 - Water hyacinth, swine excrement and earth (7:1:0,67), T4 - Water hyacinth, swine excrement and cellulosic gut (7:1:0,67), for a period of 90 days. The temperature was monitored daily, and humidity, cinder, nitrogen and total organic carbon were monitored monthly. The result obtained, during 11 months, were promising and the efficient averages of 26.3% of COD and 32.5% of BOD removal were observed, with a maximum removal of 77.2% of COD and 77.87% of BOD. About the nutrient removal, a 21.2% average of nitrogen removal was observed, with a maximum removal of 87.9%, an 11.0% average for ammoniac nitrogen, with maximum of 47.5%, and an 11.1% average and maximum of 38.9% for total phosphorus, during an average of 5 days of retention. An increase in the water turbidity was noticed during the months of high pluviometric precipitation; however, the efficiency of the process was positive during all the monitoring period, with a maximum removal of 58.1%. Considering the C/N relation as a compost maturity indicator, the T4 treatment (water hyacinth, swine excrement and cellulosic gut) had the shorter period of stabilization: 60 days. / O presente trabalho teve por objetivo avaliar o desempenho da macrófita aquática (Eichhornia crassipes), aplicada in situ em sistema de tratamento de um matadouro e frigorífico, localizado no Oeste do Estado do Paraná, com relação à remoção de nutrientes (formas de nitrogênio e fósforo total), matéria orgânica (DBO e DQO), turbidez e sólidos sedimentáveis, bem como obter dados da produção, de práticas de manejo e compostagem da biomassa gerada no sistema. As plantas foram introduzidas na quarta célula do sistema de lagoas de estabilização da indústria, ocupando 35m2 da área total delimitada para o experimento: 870m2. Durante o período de 11 meses (47 semanas) de desenvolvimento das macrófitas na lagoa, realizou-se o monitoramento de parâmetros físico-químicos, analisados com freqüência mensal e parâmetros meteorológicos, coletados com freqüência diária e/ou semanal. Com intuito de buscar informações sobre a degradação das macrófitas retiradas do sistema de tratamento, foi conduzido um experimento em planta piloto, montando-se oito leiras de compostagem com aproximadamente 0,60m3, com quatro tratamentos distintos, sendo: T1 - Aguapé (E. crassipes), T2 - Aguapé e dejeto suíno (7:1), T3 - Aguapé, dejeto suíno e terra (7:1:0,67), T4 - Aguapé, dejeto suíno e tripa celulósica (7:1:0,67), por um período de 90 dias, monitorando-se semanalmente a temperatura, e mensalmente a umidade, cinzas, nitrogênio e carbono orgânico total. Os resultados obtidos, durante os 11 meses do experimento, foram promissores e observou-se uma eficiência media de remoção de DQO de 26,3% e de DBO de 32,5%, com remoção máxima de DQO de 77,2% e de DBO de 77,8%. Em relação aos nutrientes, observou-se uma remoção média de nitrogênio total de 21,2% com máxima de 87,9%, de nitrogênio amoniacal de 11,0% com máxima de 47,5% e de fósforo total de 11,1% com máxima de 38,9%, para um tempo médio de retenção de cinco dias. Com relação à turbidez, observou-se aumento da turbidez afluente nos meses com maior índice de precipitação pluviométrica, contudo a eficiência manteve-se positiva durante todo período de monitoramento, com remoção máxima de 58,1%. Considerando a relação C/N como um indicador da maturidade do composto, observou-se que o tratamento T4 (aguapé, dejeto e tripa celulósica) obteve o menor período de estabilização do composto orgânico: 60 dias.
52

Remote sensing of the spatio-temporal distribution of invasive water hyacinth (Eichhornia crassipes) in the Greater Letaba River System in Tzaneen, South Africa

Thamaga, Kgabo Humphrey January 2018 (has links)
Thesis (MSc. (Geography)) --University of Limpopo, 2018 / Water hyacinth (Eichhornia crassipes) is recognised as the most notorious invasive species the world-over. Although its threats and effects are fully documented, its distribution is not yet understood, especially in complex environments, such as river systems. This has been associated with the lack of accurate (high spatial resolution) and robust techniques, together with the reliable data sources necessary for its quantification and monitoring. The advent of new generation sensors i.e. Landsat 8 Operational Land Imager (OLI) and Sentinel-2 MultiSpectral Instrument (MSI) data, with unique sensor design and improved sensing characteristics is therefore perceived to provide new opportunities for mapping the distribution of invasive water hyacinth in small waterbodies. This study aimed at mapping and understanding the spatio-temporal distribution of invasive water hyacinth in the Greater Letaba river system in Tzaneen, Limpopo Province of South Africa using Landsat 8 OLI and Sentinel-2 MSI data. Specifically, the study sought to identify multispectral remote sensing variables that can optimally detect and map invasive water hyacinth. Landsat 8 OLI and Sentinel-2 MSI were tested based on the spectral bands, vegetation indices, as well as the combined spectral bands plus vegetation indices, using discriminant analysis algorithm. From the findings, Sentinel-2 MSI outperformed Landsat 8 OLI in mapping water hyacinth, with an overall classification (OA) accuracy of 77.56% and 68.44%, respectively. This observation was further confirmed by a t-test statistical analysis which showed that there were significant differences (t=6.313, p<0.04) between the performance of the two sensors. Secondly, the study sought to map the spatial distribution of invasive water hyacinth in the river system over time (Seasonal). Multi-date 10 m Sentinel-2 MSI images were used to detect and monitor the seasonal distribution and variations of water hyacinth in the Greater Letaba River system. The study demonstrated that, about 63.82% of the river system was infested with water hyacinth during the wet season and 28.34% during the dry season. Sentinel-2 MSI managed to depict species spatio-temporal distribution with an OA of 80.79% during wet season and 79.04% in dry season, using integrated spectral bands and vegetation indices. New generation sensors provide new opportunities and potential for seasonal or long-term monitoring of aquatic invasive species like water hyacinth- a previously challenging task with broadband multispectral sensors. / Risk and Vulnerability Science Centre (RSVC)
53

Quantification of the cross-sectoral impacts of waterweeds and their control in Ghana

Akpabey, Felix Jerry January 2012 (has links)
The Akosombo Dam on the Volta River in Ghana was built in 1963 to provide cheap energy to fuel industry and to accelerate the economic growth of the country. It provides hydroelectric power, enhanced fishing and water transportation upstream, and improved opportunities for irrigated farming, especially in the lower reaches, and their attendant economic multiplier effects. A few years after the construction of this major dam, a rapid expansion of industrialization took place in Ghana. This brought about an exponential increase in demand for more electrical power. This led to the construction of a smaller dam at Akuse, downstream of the Akosomho Dam in 1981 and the formation of a headpond at Kpong. The impoundment of the river at the two sites (Akosombo and Kpong) caused an alteration in the existing ecological and biophysical processes in the river basin, including a slowing of the flow of the river, upstream and downstream. Changes in the natural processes, such as a reduction in the flow of the river and an increase in nutrient status of the water, resulted in an invasion of aquatic weeds, increasing the density of aquatic snails (intermediate hosts of schistosomiasis), silting and closure of the estuary, as well as other more subtle effects. The invasion of the river's main course and the dams by aquatic plants led to a corresponding reduction of navigable water both upstream and downstream. The aim of this thesis was to quantify the impact and control of waterweeds, especially water hyacinth, Eichhornia crassipes (Mart) Solms-Laubach (Pontederiaceae), in Ghana. A floral survey on the Kpong Headpond recorded 49 emergent, 12 free floating and I submerged aquatic plant species, many of which were indigenous, but the exotic or introduced water hyacinth was recorded at most of the sampling sites, and was the most abundant and had the biggest impact on the utilization of the water resource. Mats of water hyacinth served as substrates for other, indigenous species to grow out into the main channel of the headpond, including the intake point of the Kpong head works of the Ghana Water Company Limited (GWCL) and landing sites for boats. These mats resulted in a reduction of the fish (fin and shell) harvest, reducing the annual production to far below demand. Water hyacinth was also shown to have severe health implications. A survey of the Ministry of Health records showed that the prevalence of both urinary and intestinal schistosomiasis had risen significantly over time as the abundance of waterweeds, most notably water hyacinth, increased, and ranged between 70&#37; and 75&#37; but up to 100&#37; in some lakeside communities. Based on the work done by an NGO on board the medical boat ("Onipa Nua "), losses in terms of money due to the effect on health of the aquatic weed infestations on the Volta River in 2006 amounted to US$ 620,000. Economic losses due to invasive alien aquatic weeds were also calculated on the Oti River Arm of Lake Volta. It was estimated that about US$2.3 million per annum would be lost to the Volta Lake Transport Company and individual boat transport operators if this section of the river were 100&#37; covered by aquatic weeds (water hyacinth and Salvinia molesta D.S. Mitchell (Salviniaceae)). It was also estimated that US$327,038 was spent annually in monitoring and managing the weeds in the Oti River. Control interventions for aquatic weeds have been implemented in river systems in Ghana. The biological control agents Neochetina bruchi Hustache (Coleoptera, Curculionidae) and Neochetina eichhorniae Warner (Coleoptera, Curculionidae) have been used on water hyacinth infestations in the Oti River Arm of Lake Volta, the Tano River and the Lagoon complex in the south-western part of the country. Cyrtobagous salviniae Calder and Sands (Coleoptera: Curculionidae) has been used to control salvinia, and Neohydronomous affinis Hustache (Coleoptera: Curculionidae) to control water lettuce, Pistia stratiotes Lilmaeus (Araceae) in the Tano River and Lagoon complex. Although these projects have been regarded as successful, they have relied on research from elsewhere in the world and no postrelease quantification has been conducted. In evaluating the impact of the biological control agents Neochetina bruchi and Neochetina eichhorniae weevils on water hyacinth infestations in the Tano River, fresh adult feeding scars were recorded as well as the numbers of adult weevils on each water hyacinth plant sampled at six sites. Despite being released in 1994, weevil numbers and resultant damage to plants in the Tano Lagoon was low in comparison to other regions of the world where these agents have been used. The main reason for this is that this lagoon floods seasonally, washing weevil-infested plants out to sea. Water hyacinth then re-infests the lagoon from seed and the weevil populations are low. To resolve this situation, two courses of action are proposed. The first is to mass rear the weevils along the shore of the lagoon and release them when the first seedlings recruit. The second proposal is that additional agents that have shorter lifecycies and are more mobile than the weevils should be released. To this end, the water hyacinth mirid, Eccritotarsus catarinensis (Carvalho) (Hemiptera: Miridae) was imported from South Africa and released onto the Tano Lagoon in 2009. Retrospective laboratory host specificity trials were conducted on Neachetina eichharniae and Neachetina bruchi weevils 15 years after their release into Ghana to see if any variation in their host ranges had occurred. Considerable damage was inflicted on the E. crassipes leaves by the Neachetina weevils, while little feeding damage was recorded on both Heteranthera callifalia Kunth. (Pontederiaceae) and Eichharnia natans (P.Beauv.) Solms (Pontederiaceae). All the weevils introduced on H callifalia and E. natans died after the first week. This study served to confirm the host specificity and thereby the safety of these agents. Invasive alien aquatic macrophytes have negative impacts on the environment and economy of Ghana. The control of these weeds is essential to socioeconomic development and improved human health standards in riparian communities. Biological control offers a safe and sustainable control option, but requires diligent implementation. However, aquatic weed invasion is more typically a result of the anthropogenically induced eutrophication of water bodies, and this is the main issue that has to be addressed.
54

Efeito de pontas de pulverização e de arranjos populacionais de plantas de Eichhornia crassipes (Mart.) Solms., Salvinia auriculata Aubl. e Pistia stratiotes L. na deposição de calda de pulverização /

Marchi, Sidnei Roberto de, 1964- January 2006 (has links)
Orientador: Dagoberto Martins / Banca: Robinson Antonio Pitelli / Banca: Gerson Augusto Gelmini / Banca: Mario Sergio Tomazela / Banca: Marcus Barifouse Matallo / Resumo: Este trabalho teve como objetivo avaliar a quantidade de calda de pulverização depositada na água e em folhas de Eichhornia crassipes (Mart.) Solms, Salvinia auriculata Aubl e Pistia stratiotes L. em condições variáveis de arranjos populacionais e dois tipos de pontas de pulverização (ConeJet TXVK-8 e TeeJet DG 11002 VS). Para tanto, foi conduzido um experimento em caixas d’água composto por três Situações distintas. Na Situação Aguapé, além da proporção de dominância total correspondente à cobertura de 100% da caixa d’água pelas plantas de aguapé, foram utilizados os arranjos (ou proporções) com as espécies de salvinia ou alface d’água a 75%:25%, 50%:50%, 25%:75%. Adotou-se as mesmas proporções na Situação Salvínia e na Situação Alface d’água, sendo que cada Situação foi determinada pela predominância total de salvínia ou alface d’água, respectivamente, na caixa d’água. Uma densidade tripla, onde as três espécies foram igualmente dispostas na proporção de 33,33%, foi utilizada como testemunha. Soluções dos corantes Amarelo Tartrasina FDC-5 a 3.500 ppm e Azul Brilhante FDC-1 a 1.000 ppm foram utilizados como traçadores para as pontas TXVK-8 e DG 11002VS, respectivamente. A pulverização de ambas soluções foram efetuadas na mesma unidade experimental, com um intervalo de 30 minutos entre si, através de um pulverizador costal pressurizado com CO2 e calibrado de modo a proporcionar um volume de aplicação aproximado de 200 L/ha. Amostras de água dos reservatórios foram coletadas antes e após as aplicações com o objetivo de avaliar a quantidade de calda de pulverização que não atingiu o alvo. Imediatamente após a coleta da 2 água, as plantas presentes nos reservatórios foram lavadas com água destilada até remoção total dos corantes depositados nas folhas. Placas de plástico contendo... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The present research had as objective to quantify the spray deposition on water and leaves of water hyacinth (Eichhornia crassipes (Mart.) Solms), water fern (Salvinia auriculata Aubl.) and water lettuce (Pistia stratiotes L.) according to various population arrangements and two nozzle type (ConeJet TXVK-8 and TeeJet 11002VS). The trial was carried out under reservoirs conditions using three different Situations. At Water hyacinth Situation, besides the total dominancy proportion equivalent to 100% of reservoir covering by water hyacinth plants, it was used three others combinations involving water hyacinth and water fern or water lettuce plants, as following: 75%:25%, 50%:50% and 25%:75%. The same combinations were also used at Water Fern Situation and Water Lettuce Situation, being each Situation determined by total dominancy of water fern or water lettuce in the 4 reservoirs, respectively. A triple ratio, where the three species were equally disposed at proportion of 33,33%, was used as check. Dye solutions of FD&C Yellow n. 5 at 3,500 ppm and FD&C Blue n. 1 at 1,000 ppm were used as spraying tracers for TXVK-8 and DG 11002 VS nozzles, respectively. Both solutions were sprayed at same plot within at 30 minutes interval each one through a CO2 pressured backpack knapsack calibrated to delivery a spray volume around 200 L/ha. Samples of reservoirs water were taken before and after sprays in order to evaluate the carrier quantity that not reaches the target. After that, the plants present at reservoirs were washed with distillated water until totally dyes removal deposited on the leaves. Plastic dishes containing 20 mL of distillated water were disposed in each experimental plot in order to check the spray efficacy and possible drift losses. Absorbance measures at 427 and 630 nm of wavelength were procedures... (Complete abstract, click electronic access below) / Doutor
55

Uso de resíduos orgânicos como recondicionante de subsolo degradado e efeito na atividade microbiana, micorrização e crescimento do barbatimão

Calgaro, Hemerson Fernandes [UNESP] 05 December 2006 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:29:43Z (GMT). No. of bitstreams: 0 Previous issue date: 2006-12-05Bitstream added on 2014-06-13T20:19:55Z : No. of bitstreams: 1 calgaro_hf_me_ilha.pdf: 561756 bytes, checksum: 08e7ef755d47a0302680f6ed11722b36 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / A região de Ilha Solteira apresenta em sua maior extensão, como cobertura vegetal, o cerrado. No final da década de 60, com a construção da Usina Hidrelétrica de Ilha Solteira, algumas áreas foram desmatadas e serviram como .área de empréstimo. Os solos pertencentes a estas localidades foram subtraídos e estas áreas ficaram com suas características químicas e biológicas distantes das ideais. O desenvolvimento da vegetação depende das condições do substrato; melhorias de alguns dos atributos do subsolo destas áreas poderiam ser obtidos com a adição de resíduos orgânicos e/ou adubos químicos. O trabalho teve como objetivo avaliar o uso de resíduos orgânicos no crescimento do Stryphnodendron polyphyllum e como recondicionantes de subsolo degradado. A área utilizada para o experimento faz parte da Fazenda Experimental de Pesquisa e Extensão - FEPE, UNESP - Ilha Solteira, em Selvíria . MS. O subsolo continua a apresentar caráter ácido e pobre em nutrientes, após um ano de avaliação. O diâmetro do colo e altura de planta apresentam resultados crescentes ao longo do período, com os maiores valores para os tratamentos que receberam calagem, N + P e resíduos orgânicos. O carbono da biomassa, ao longo do experimento, apresentou tendências à estabilização enquanto que o quociente metabólico diminuiu no mesmo período. A colonização micorrízica e número de esporos foram influenciados positivamente pela presença de resíduos orgânicos, os quais apresentaram os maiores valores. / Ilha Solteira region is covered for the most by cerrado as vegetation. In the late 60s as a result of the building of Hydroelectric Power Station of Ilha Solteira, some areas have been deforested and were used as loan areas. Thus, the soils belonging to these locations were subtracted and these areas became chemically poor soils with both physical and biological properties far from the ideal ones. The vegetation development depends on the substrate conditions; the improvement of some subsoil features in these areas could be obtained by adding organic residues and/or chemical fertilizers. This work aimed at evaluating the use of organic residues in the growth of Stryphnodendron polyphyllum and as a reconditioner of degraded subsoil. The area taken for the experiment is part of the Experimental Farm of Teaching and Research, FEPE, UNESP - Ilha Solteira, in Selvíria . MS. However, the subsoil keeps presenting the same acid characteristic and poor nutrient levels after a year of assessment. The column diameter and the height of the plant presented increasing results during the period; the highest values were for the treatments which received liming, N + P and organic residues. During the experiment, the carbon of the microbe biomass presented tendencies to the stabilization while the metabolic quotient decreased in the same period. The mycorrhization and the number of the spores were positively influenced by the presence of organic residues, showing the highest values.
56

ADSORÇÃO DE COMPOSTOS FENÓLICOS EM CARVÃO ATIVADO PREPARADO A PARTIR DO AGUAPÉ (Eichhornia crassipes) / ADSORPTION OF PHENOLIC COMPOUNDS IN ACTIVATED CARBON PREPARED FROM WATER HYACINTH (Eichhornia crassipes)

Barbosa, Charles Silva 26 November 2013 (has links)
Made available in DSpace on 2016-08-19T12:56:42Z (GMT). No. of bitstreams: 1 dissertacao Charles.pdf: 1084037 bytes, checksum: c0b51053c8b5238fee81d3c52d6c8a59 (MD5) Previous issue date: 2013-11-26 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Activated carbon was produced from the water hyacinth (CAA) by impregnation with ZnCl₂ (1:2), followed by pyrolysis at 700 °C, under N₂, and presented a surface area of 640.4 m²gˉ¹. We ve done kinetics tests, equilibrium and thermodynamics tests, and also tests to verify the influence of pH, temperature and initial concentration on adsorption process, using the following phenolic compounds: fenol, o cresol and m cresol. The pHzpc value of CAA was estimated at 5.4. Kinetic studies were performed at pH 10 due to the greater efficiency of removal of phenolic compounds. The kinetic models of pseudo-first and second orders were applied at temperatures 10, 25, 35 and 45°C, and the second order model (R² ≥ 0.94) was that best modeled the experimental data. The adsorption isotherms were obtained by varying the phenolic compounds concentration in the range from 150 to 1000 mg Lˉ¹. The Freundlich and Langmuir adsorption isotherms models have been applied to fit the experimental data, and the Freundlich model was the best one. The maximum quantity adsorbed of each compound, obtained from Langmuir, at 45 oC followed the order: fenol (163.7 mg gˉ¹) > o-cresol (142.3 mg gˉ¹) > m-cresol (130.2 mg gˉ¹). The thermodynamic parameters confirmed the spontaneity of the adsorptive processes, which are endothermic, but with increasing entropy. / Carvão ativado foi produzido a partir de aguapé (CCA) por impregnação com ZnCl₂ (1:2), seguida por pirólise a 700 °C, sob N₂, e apresentou área superficial de 640,4 m²gˉ¹. Foram realizados testes cinéticos, de equilíbrio e termodinâmicos, além de testes para verificar a influência de pH, temperatura e concentração inicial no processo de adsorção, utilizando os seguintes compostos fenólicos: fenol, o cresol e m cresol. O valor do pHpcz do CAA foi estimado em 5,4. Os estudos cinéticos foram realizados em pH 10, devido a maior eficiência de remoção dos adsorvatos. Os modelos cinéticos de pseudo-primeira ordem, segunda ordem e Elovich foram aplicados nas temperaturas 10, 25, 35 e 45 ºC, sendo o modelo de segunda ordem (R² ≥ 0,94) o que melhor representou os dados experimentais. As isotermas de adsorções foram obtidas variando-se a concentração dos compostos fenólicos na faixa de 150 a 1000 mg Lˉ¹. Os modelos isotérmicos de Freundlich e Langmuir foram aplicados na avaliação dos resultados experimentais, sendo o modelo proposto por Freundlich o que mais se aproximou dos resultados experimentais. A quantidade máxima adsorvida de cada composto, obtida a partir de Langmuir, na temperatura de 45 ºC seguiu a ordem: fenol (163,7 mg gˉ¹) > o-cresol (142,3 mg gˉ¹) > m-cresol (130,2 mg gˉ¹). Os parâmetros termodinâmicos confirmaram a espontaneidade dos processos de adsorção, os quais se apresentaram endotérmicos, mas com aumento de entropia.
57

Modelagem sistêmica do ciclo de vida do aguapé no Pantanal e anãlise do uso desta biomassa para a produção de bio-óleo e bio-fertilizante / System modeling of water hyacinth life cycle in Pantanal and analysis of the use of this biomass for bio-oil and bio-fertilizer production

Buller, Luz Selene, 1970- 02 October 2012 (has links)
Orientadores: Enrique Ortega Rodriguez, Ivan Bergier Tavares de Lima / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-19T11:57:30Z (GMT). No. of bitstreams: 1 Buller_LuzSelene_M.pdf: 2995716 bytes, checksum: 7169eaed43d8a521a5154da2d23578ea (MD5) Previous issue date: 2012 / Resumo: O Pantanal ocupa uma área extensa do Brasil em torno de 140.000 km²; seus ecossistemas são caracterizados por áreas com alagamento periódico, campos inundados constantemente e ambientes aquáticos naturais com lagoas (baías), rios e canais (vazantes e corixos); não existem quedas d¿ água para a geração de energia elétrica dentro da bacia. Em virtude das áreas alagadas existem poucas vias para o abastecimento de combustíveis para as fazendas produtoras que, assim, dependem fortemente de diesel e lenha como fonte de energia. Além disso, as cidades da região dependem da energia elétrica originária de outros estados da federação e a produção industrial (cimento e ferro gusa) é baseada em carvão vegetal, cuja origem é questionável, possivelmente do desmatamento do Cerrado. O uso de fontes alternativas de biomassa produzidas localmente poderia amenizar a carência energética no Pantanal. O aguapé, que se desloca nas lagoas e rios do Pantanal na forma de ilhas flutuantes, pode ser uma fonte alternativa de biomassa para a obtenção de combustíveis sólidos, líquidos e gasosos renováveis produzidos e distribuídos localmente. Esta pesquisa objetivou uma análise do ciclo de vida do aguapé na região de Corumbá mediante estudos teóricos que permitiram modelar e simular a dinâmica de crescimento (nas baías e margens dos rios) e de decaimento do aguapé (decomposição), elaborar cenários de colheita sustentável e dos mecanismos de remoção de nutrientes pelo aguapé em diferentes épocas do ano e realizar a avaliação emergética da produção natural de biomassa e de produtos derivados da conversão termoquímica desta biomassa, bio-óleo e bio-carvão. O estudo foi complementado com uma avaliação econômica de uma unidade industrial de pirólise rápida de biomassa. Os resultados obtidos permitem que tomadores de decisão avaliem de modo sistêmico a viabilidade ambiental e econômica da criação de um sistema para extração e aproveitamento de biomassa de aguapé. Os níveis de colheita estudados e os indicadores emergéticos e econômicos apontam para a viabilidade ecológica e econômica de um sistema operando com extração de 1% da biomassa de aguapé escoada no rio Paraguai. Para níveis maiores de extração, os resultados trazem à tona questões que requerem estudos adicionais a fim de garantir uma visão ecológica sobre a exploração de recursos naturais do Pantanal que é um importante provedor de serviços ambientais. As interferências na região devem ser baseadas em mecanismos de monitoramento contínuo dos impactos ambientais e socioeconômicos da atividade antrópica e em premissas de responsabilidade socioambiental no longo prazo / Abstract: Pantanal covers an extensive area of Brazil, around 140.000 km²; its ecosystems are characterized by periodic flooded areas, permanently flooded fields and natural aquatic environments with bays, rivers, streams and channels (locally denominated ¿vazantes¿ and ¿corixos¿); there are no water falls for power generation within the basin. Because of the flooded areas there are few routes for fuel supply to farms that rely heavily on diesel fuel as an energy source. In addition, the cities of the region depend on the energy originated in other states of the federation and its industrial production (cement and cast iron) is based on charcoal, whose origin is questionable, possibly from the deforestation of the Cerrado (Brazilian Savanna). The use of alternative sources based on biomass locally produced could ease energy shortages in the Pantanal. Water hyacinth, which flows in the lakes and rivers of Pantanal in the form of floating islands, can be an alternative source of biomass to obtain solid, liquid and gaseous renewable fuels locally produced and distributed. This research aimed the analysis of water hyacinth life cycle in Corumbá by theoretical studies that allowed to model and to simulate the growth dynamics (in the bays and riverbanks) and water hyacinth decay (decomposition), to elaborate scenarios of sustainable harvesting level and mechanisms of nutrient removal by water hyacinth at different periods of the year and to perform the emergy evaluation of the natural production of biomass and of the industrial products derived from the thermochemical conversion of biomass, bio-oil and biocharcoal. The study was complemented with an economic evaluation of one plant of biomass fast pyrolysis. The results allow decision makers to systemically evaluate the environmental and economic feasibility of a system for extraction and utilization of water hyacinth biomass. Harvest levels studied and emergy and economic indicators obtained indicate the ecological and economic feasibility of an operating system with extraction of 1% of the water hyacinth biomass that flows in Paraguay River. For higher levels of extraction, the results bring to light issues that require further investigation to ensure an ecological view of the exploitation of natural resources of Pantanal that is a leading provider of environmental services. The interference in the region should be based on mechanisms for continuous monitoring of environmental and socioeconomic impacts of human activity and on premises of social and environmental responsibility in the long term / Mestrado / Engenharia de Alimentos / Mestre em Engenharia de Alimentos
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The effect of temperature on the feeding and development of Neochetina eichhorniae weevil larvae on water hyacinth (Eichhornia crassipes)

Bokotomba, Ndongo Fyfy January 2017 (has links)
A dissertation submitted to the Faculty of Science, University of the Witwatersrand, in partial fulfilment of the requirements for the degree of Master of Science. Johannesburg, March 2017. / Water hyacinth (Eichhornia crassipes) is an example of an alien invasive plant, threatening ecosystems around the world. Taking into consideration all the negative impacts caused by the proliferation of water hyacinth, many control measures have been implemented to manage this weed. These include mechanical control, chemical control and biological control. But in recent years, the focus has shifted towards natural enemies for control (biological control) of water hyacinth because they have many advantages for environmental safety. However, in South Africa, success is limited in most parts of the country. Factors affecting the success of biological control of water hyacinth in South Africa have been attributed in part to weather conditions. Therefore, further studies and other strategies are needed to reinforce the biological control of water hyacinth. This is why this research investigated the influences of temperature on Neochetina eichhorniae larvae feeding and development on water hyacinth, to contribute to the future management of water hyacinth biological control. To measure the effect of temperature on the feeding and development of Neochetina eichhorniae larva, experiments were conducted at four fixed temperatures (15 °C, 20 °C, 25 °C, and 30 °C). Larval feeding is expected to be greater and the development faster at warm temperatures compared with cold temperatures. The results of this study confirmed that, both feeding and larval development increased with an increase in temperature. The highest larval feeding damage was recorded at 30°C and the lowest at 15°C. Similar to the feeding of larvae, warmer temperatures were more favourable to the growth of larvae than cold temperatures; all larvae found at 30°C were in their third instars (with 0.72 mm being the biggest headwidth found) while all larvae at 15°C were in the first instars (with 0.28 mm being the smallest headwidth found). Even if the optimal temperature for larval performance took place at 30 °C (with a high amount of biomass removal), it was at 25 °C that the larvae had a larger effect on the growth of water hyacinth. Larval feeding damage reduced the growth of water hyacinth by 30 % at 25 °C and only affected 24 % of water hyacinth growth at iv 30 °C. Therefore, for the biocontrol of water hyacinth, the ideal temperature to slow the progression of the weed will be recommended at between 25- 30 °C. / LG2017
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Study on treatment of domestic wastewater of an area in Tu Liem district, Hanoi, by water hyacinth / Nghiên cứu xử lý nước thải sinh hoạt tại một khu dân cư thuộc quận Từ Liêm, Hà Nội, bằng Bèo lục bình

Pham, Khanh Huy, Nguyen, Pham Hong Lien 09 December 2015 (has links) (PDF)
Domestic wastewater is one of the most interested environmental issues in Vietnam, especially in big cities and suburban residential areas. Most of the wastewater was not treated in the right way before discharging to environment. In this research, the author used water hyacinth as a main aquatic plant in aquatic pond model to treat wastewater. The experiment was operated continuously in 1 year with hydraulic retention time (HRT) is 11 and 18 days. Hydraulic loading rate (HRL) is 300 and 500 m3/ha/day, respectively. Treatment efficiency of the model for TSS is 90% (remaining 6 -12mg/l); COD, BOD5 is 63 - 81% (remaining 10 - 48mg/l); TP is 48 – 50% (remaining 3.5 - 9.8mg/l); TKN is 63 - 75% (remaining 8 - 17mg/l). Polluted parameters in effluent were lower than A and B levels of Vietnam standard QCVN 14: 2008/BTNMT and QCVN 40: 2011/BTNMT. The doubling time of water hyacinth in summer is 18days, and in autumn and winter is 28.5 days. Experiment results showed that we can use water hyacinth in aquatic pond to treat domestic wastewater with medium scale. We can apply this natural treatment method for residential areas by utilizing existing natural ponds and abandoned agricultural land with capacity up to 500m3/ha day. However, to get better efficiency we should combine with other aquatic plant species to treat wastewater and improve environmental landscape. / Nước thải – xử lý nước thải sinh hoạt hiện đang là một trong những vấn đề môi trường được quan tâm tại Việt Nam nhất là tại các thành phố lớn và các khu dân cư. Hầu hết lượng nước thải chưa được xử lý đúng cách trước khi thải ra môi trường. Trong nghiên cứu này, tác giả sử dụng mô hình hồ thủy sinh và sử dụng cây Bèo lục bình để xử lý nước thải sinh hoạt của một khu dân thuộc huyện Từ Liêm, tại khu vực này nước thải bị thải trực tiếp vào sông Nhuệ. Thực nghiệm đã được tiến hành trong khoảng thời gian một năm, trải qua các mùa của khu vực miền Bắc với hai chế độ vận hành HRT là 18 và 11 ngày, tương ứng với tải trọng thủy lực HRL là 300 và 500 m3/ha/ngày. Kết quả cho thấy mô hình thủy sinh sử dụng cây bèo lục bình cho kết quả tốt, hiệu suất xử lý với các chất ô nhiễm đạt được như sau: chất rắn lơ lửng đạt 90%, COD, BOD5 đạt 63 - 81%, Phốt pho tổng giảm tới 48 -50%, Nitơ tổng giảm tới 63 - 75%. Hàm lượng các chất ô nhiễm trong nước thải đầu ra của mô hình đều thấp hơn ngưỡng A và B của các tiêu chuẩn QCVN 14: 2008/BTNMT và QCVN 40: 2011/BTNMT. Bên cạnh đó tác giả cũng đã xác định định được tốc độ sinh trưởng của cây bèo tại khu vực miền Bắc là 18 ngày vào mùa hè và 28.5 ngày vào mùa thu đông. Kết quả nghiên cứu cho thấy có thể sử dụng bèo lục bình để xử lý nước thải sinh hoạt, với qui mô vừa và nhỏ và nên áp dụng cho các khu vực ven đô, nông thôn nơi có diện tích đất rộng hoặc tại các hồ sinh thái của các khu đô thị. Tuy nhiên, để hiệu quả tốt hơn ta cần kết hợp với nhiều loại thực vật thủy sinh khác để ngoài tác dụng xử lý nước thải mà còn tạo cảnh quan môi trường xung quanh.
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How elephants utilize a miombo-wetland ecosystem in Ugalla landscape, Western Tanzania

Kalumanga, Elikana January 2015 (has links)
African elephants are ‘keystone’ species with respect to biodiversity conservation in Africa since they maintain habitats that support several animal communities by changing vegetation structure through foraging and by dispersing seeds between landscapes. Elephants are also ‘flagship’ species because, given their impressive size, they can make people sympathetic and stimulate local and international concerns for their protection. Economically, elephants contribute to national revenues as tourists are willing to pay to watch them. Despite all these factors, little is known however about elephant movement and how they utilize resources, especially in miombo-wetland ecosystems. This thesis investigates how elephants utilize resources in a miombo-wetland ecosystem in the Ugalla landscape of Western Tanzania over different protected areas containing different resource users. Using Global Positioning System (GPS) collars fitted to six elephants, it was observed that some elephant families are not confined in one protected area in the Ugalla landscape. Rather, they moved readily between different protected areas. Elephant movements were restricted to areas near the rivers, especially the Ugalla River, during the dry season and were dispersed widely during the wet season. As they move, elephants in the miombo woodlands of Ugalla selected the most abundant woody plants for browsing. Common to many woody plants, the browsed plants were short of mineral nutrients (e.g., sodium, calcium). Elephants obtained additional minerals by eating soils from certain termite mounds. Soils from termite mounds are richer in mineral elements (e.g., sodium, calcium, iron) compared to soils from the surrounding flood plain or compared to the browsed plants. However, the recorded termite mounds from which elephants eat soils were not evenly distributed in the landscape but confined mainly to the flood plains in the Ugalla Game Reserve. The Ugalla River, which is the main source of water for the elephants and other animals and also supports fishing activities by the local people in Ugalla during the dry seasons, is infested by the water hyacinth (Eichhornia crassipes). Such infestation potentially limits access to these precious surface water supplies. In addition at the regional level, the Ugalla River is among the major rivers that flow into the Lake Tanganyika which is shared by the countries of Tanzania, Burundi, Democratic Republic of Congo and Zambia. Thus, the spread of water hyacinth if left unchecked threatens to impact Lake Tanganyika, affecting many countries and ecosystem services. This thesis highlights that sustainable conservation of biodiversity in different protected areas in the Ugalla landscape requires an integrated management approach that will embrace conservation of different interrelated landscape resources required by both wildlife and the rural poor populations for their livelihoods. Regular coordinated wildlife anti-poaching patrols should be initiated across the entire Ugalla landscape because the elephants, among other wildlife, utilize different protected areas in Ugalla. Local communities should also be engaged in conservation initiatives (e.g., controlling the spread of the water hyacinth) as these directly impact local livelihoods. / <p>At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 1: Manuscript. Paper 2: Manuscript. Paper 3: Manuscript. Paper 4: Manuscript.</p> / INTEGRATED NATURAL RESOURCES MANAGEMENT

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