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Ecological effects of water hyacinth (Eichhornia crassipes) on Lake Chapala, MexicoVillamagna, Amy Marie 15 April 2009 (has links)
Water hyacinth (Eichhornia crassipes) is a floating non-native plant that has been reoccurring in Lake Chapala, Jalisco, Mexico for more than 100 years. In this research, I explore the effects of water hyacinth on freshwater ecosystems worldwide and specifically on Lake Chapala.
In chapter 1, I reviewed studies conducted on water hyacinth worldwide and found that the effects of water hyacinth on water quality are similar but the magnitude of effects is dependent on the percent cover and potentially the spatial configuration of water hyacinth mats. Water hyacinth's effect on aquatic invertebrates, fish, and waterbirds is less predictable and dependent on conditions prior to invasion. In chapter 2, I tested for relationships between percent water hyacinth cover and waterbird abundance, species diversity, community composition, and habitat use. In general, I found a weak positive relationship or no relationship between these variables. In Chapter 3, I monitored habitat use by American Coots (Fulica americana) in a variety of habitats around Lake Chapala. I found that the time spent in water hyacinth positively corresponded to the percent water hyacinth cover and that the time foraging in water hyacinth was positively related to the time spent in water hyacinth.
In Chapter 4, I compared invertebrate assemblages in open water to those within and at the edge of water hyacinth mats, emergent vegetation, and submerged trees. I also examined invertebrate assemblages within the roots of water hyacinth plants and compared assemblages between patch and shoreline water hyacinth plants. I found that density and taxonomic richness of water column invertebrates were generally higher in association with water hyacinth, but that mean percent cover of water hyacinth affected the magnitude of differences among habitats and vegetation types. I did not find significant differences in root invertebrate density and taxonomic richness between patch and shoreline water hyacinth plants. In chapter 5, I discuss how water hyacinth affected dissolved oxygen and water transparency on a small, localized scale, but was not the driving factor for seasonal differences. The overall results suggest that water hyacinth had a minimal ecological effect on Lake Chapala during this study. / Ph. D.
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Evaluation of water hyacinth (Eichhornia crassipes) suitability as feedstock for biogas productionMakofane, Rosina 08 1900 (has links)
The suitability of water hyacinth in biogas production was evaluated as a means of waste management in the interests of sustainable energy production. Batch anaerobic digestion (AD) of water hyacinth was conducted to determine the optimal pre-treatment method for maximum methane production. Physical pre-treatment methods produced a highest cumulative methane of 2.3 L during batch AD. The selected pre-treatment method, hand-cutting, was further evaluated in a semi-continuous AD using both mono- and co-digestion. The emphasis was on identifying microbial communities involved and their response to organic loading rates (OLRs). The Illumina Miseq results proved that bacterial communities were more sensitive to disturbances caused by irregular OLRs as compared to archaeal communities. In addition, the variation in substrate nutrients as a result of mono- and co-digestion of water hyacinth, contributed to variations in the bacterial diversity. For example, Bacteroides and Petrimonas diversity varied between mono- and co-digestion. Overall, the study verified that water hyacinth is a suitable feedstock for biogas production and the simple pre-treatment methods are recommended. Furthermore, OLRs influenced the microbial community structure and associated biogas yield. / National Research Foundation (South Africa) / Environmental Science / M. Sc. (Environmental Science)
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"Is more, less?" : insect-insect interactions in a biological control context using water hyacinth as a modelWeyl, Philip Sebastian Richard January 2012 (has links)
Interactions between insects have been shown to be important regulators of population abundances and dynamics as well as drivers of spatial segregation and distribution. These are important aspects of the ecology of insects used in biological control and may have implications for the overall success of a particular programme. In the history of biological control there has been a tendency to release a suite of agents against a weed, which in some cases has increased the level of success, while in others little change has been observed. In most of these cases the implications of increasing the level of complexity of the system is not taken into account and there is little research on the effect of releasing another agent into the system. A brief meta-analysis was done on all the biological control programmes initiated in South Africa. Emphasis was placed on multi-species releases and the effects that overlapping niches were having on the number of agents responsible for the success of a programme. Where overlapping niches were present among agents released the number of agents responsible for success was lower than the number established. Water hyacinth, Eichhornia crassipes (Martius) Solms-Laubach in South Africa has more arthropod agents released against it than anywhere else in the world, yet control has been variable. If the biology and host utilisation of all the agents against water hyacinth is considered, a definite overlap of niches is apparent in at least one life stage of all the agents. Therefore the probability of these insects interacting is high, especially if they are established at the same site in the field. Three of the insects released in South Africa have been selected to investigate possible interactions. They are Neochetina eichhorniae Warner, Neochetina bruchi Hustache and Eccritotarsus catarinensis (Carvalho). Y-tube olfactometer bioassays were used to measure responses of these insects to water hyacinth with prior feeding damage by either conspecifics or heterospecifics. This was done to determine whether olfactory cues played a role in host acceptability and avoidance of conspecifics or heterospecifics. The insects were given a choice between damaged and undamaged plants in various combinations. There was a significant preference for the undamaged plants when given a choice between undamaged and damaged plants. However when the insects were given a choice between two damaged plants there was no discrimination between heterospecific or conspecific damaged plants. This may indicate that there is little or no ecological cost for the insect to share a plant with other insects utilising a similar resource. Insect – insect interactions were investigated in a common garden plot experiment to measure the impact that pairwise combinations of the insect may have on their performance. There was a significant interaction between the mirid E. catarinensis and the weevil N. eichhorniae, with the weevil not performing as well when in combination with the mirid than when alone. Interestingly there was a negative interaction between the two weevil species when in combination, however it was impossible to determine which species was being affected if not both. None of the insects performed significantly better when in combination with another insect. A field study on Wriggleswade Dam in the Eastern Cape, South Africa was initiated to determine whether the relationship between the mirid E. catarinensis and the weevil N. eichhorniae could be determined in the field. The performance of the insects at the different sites in the field suggests that there was an interaction between the agents. This interaction did not limit the establishment of either insect at a site, but it did result in one insect dominating at a site over another. Interactions between the three species of insect tested in this thesis suggest that there are both negative and neutral relationships between them. A basic comparison between the insect performances from 15 sites around the country was done to determine if the spatial segregation observed in the field could be extrapolated to the natural South African situation. The interaction observed between N. eichhorniae and E. catarinensis does seem to extrapolate to the general South African situation where there is definite spatial segregation on a landscape level. The co–occurrence of the two Neochetina weevils at these sites suggests that the negative relationship observed between them in the common garden experiment does not extrapolate to the field. The results from this thesis suggest that the interactions between the agents tested would not limit establishment or have significant ramifications on performance. However, there may be spatial and temporal segregation of these species in the introduced range.
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Uso de aguapé (Eichhornia crassipes) em sistema de tratamento de efluente de matadouro e frigorífico e avaliação de sua compostagemMees, Juliana Bortoli Rodrigues 27 March 2006 (has links)
Made available in DSpace on 2017-07-10T19:24:44Z (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.
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Uso de aguapé (Eichhornia crassipes) em sistema de tratamento de efluente de matadouro e frigorífico e avaliação de sua compostagemMees, 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.
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Remote sensing of the spatio-temporal distribution of invasive water hyacinth (Eichhornia crassipes) in the Greater Letaba River System in Tzaneen, South AfricaThamaga, 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)
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Quantification of the cross-sectoral impacts of waterweeds and their control in GhanaAkpabey, 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% and 75% but up to 100% 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% 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.
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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 dágua composto por três Situações distintas. Na Situação Aguapé, além da proporção de dominância total correspondente à cobertura de 100% da caixa dágua pelas plantas de aguapé, foram utilizados os arranjos (ou proporções) com as espécies de salvinia ou alface dágua a 75%:25%, 50%:50%, 25%:75%. Adotou-se as mesmas proporções na Situação Salvínia e na Situação Alface dágua, sendo que cada Situação foi determinada pela predominância total de salvínia ou alface dágua, respectivamente, na caixa dágua. 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
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Uso de resíduos orgânicos como recondicionante de subsolo degradado e efeito na atividade microbiana, micorrização e crescimento do barbatimãoCalgaro, Hemerson Fernandes [UNESP] 05 December 2006 (has links) (PDF)
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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.
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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)
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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.
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