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Evaluation of a plant-herbivore system in determining potential efficacy of a candidate biological control agent, cornops aquaticum for water hyacinth, eichhornia crassipesBownes, Angela January 2009 (has links)
Water hyacinth, Eichhornia crassipes Mart. Solms-Laubach (Pontederiaceae), a freefloating aquatic macrophyte of Neotropical origin, was introduced into South Africa as an ornamental aquarium plant in the early 1900’s. By the 1970’s it had reached pest proportions in dams and rivers around the country. Due to the sustainability, cost efficiency and low environmental risk associated with biological control, this has been a widely used method in an attempt to reduce infestations to below the threshold where they cause economic and ecological damage. To date, five arthropod and one pathogen biocontrol agents have been introduced for the control of water hyacinth but their impact has been variable. It is believed that their efficacy is hampered by the presence of highly eutrophic systems in South Africa in which plant growth is prolific and the negative effects of herbivory are therefore mitigated. It is for these reasons that new, potentially more damaging biocontrol agents are being considered for release. The water hyacinth grasshopper, Cornops aquaticum Brüner (Orthoptera: Acrididae), which is native to South America and Mexico, was brought into quarantine in Pretoria, South Africa in 1995. Although the grasshopper was identified as one of the most damaging insects associated with water hyacinth in its native range, it has not been considered as a biocontrol agent for water hyacinth anywhere else in the world. After extensive host-range testing which revealed it to be safe for release, a release permit for this candidate agent was issued in 2007. However, host specificity testing is no longer considered to be the only important component of pre-release screening of candidate biocontrol agents. Investigating biological and ecological aspects of the plant-herbivore system that will assist in determination of potential establishment, efficacy and the ability to build up good populations in the recipient environment are some of the important factors. This thesis is a pre-release evaluation of C. aquaticum to determine whether it is sufficiently damaging to water hyacinth to warrant its release. It investigated interactions between the grasshopper and water hyacinth under a range of nutrient conditions found in South African water bodies as well as the impact of the grasshopper on the competitive performance of water hyacinth. Both plant growth rates and the response of water hyacinth to herbivory by the grasshopper were influenced by nutrient availability to the plants. The ability of water hyacinth to compensate for loss of tissue through herbivory was greater under eutrophic nutrient conditions. However, a negative linear relationship was found between grasshopper biomass and water hyacinth performance parameters such as biomass accumulation and leaf production, even under eutrophic conditions. Water hyacinth’s compensatory ability in terms of its potential to mitigate to detrimental effects of insect feeding was dependent on the amount of damage caused by herbivory by the grasshopper. Plant biomass and the competitive ability of water hyacinth in relation to another freefloating aquatic weed species were reduced by C. aquaticum under eutrophic nutrient conditions, in a short space of time. It was also found that grasshopper feeding and characteristics related to their population dynamics such as fecundity and survival were significantly influenced by water nutrient availability and that environmental nutrient availability will influence the control potential of this species should it be released in South Africa. Cornops aquaticum shows promise as a biocontrol agent for water hyacinth but additional factors that were not investigated in this study such as compatibility with the South African climate and the current water hyacinth biocontrol agents need to be combined with these data to make a decision on its release. Possible management options for this species if it is to be introduced into South Africa are discussed.
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The impact on biodiversity, and integrated control, of water hyacinth, Eichhornia crassipes (Martius) Solms-Laubach (Pontederiaceae) on the Lake Nsezi - Nseleni River systemJones, Roy William January 2009 (has links)
Water hyacinth, Eichhornia crassipes (Martius) Solms-Laubach (Pontederiaceae), a free floating aquatic plant was discovered by C. von Martius in 1823 in Brazil. It is believed to have been introduced into South Africa, as an ornamental plant, in 1908 to the Cape Province and Natal. Since its introduction, water hyacinth has spread throughout South Africa to the detriment of all aquatic systems that it has been introduced to directly or indirectly. The weed was first positively identified on the Nseleni and Mposa rivers on the Nseleni Nature Reserve which is a protected area near Richards Bay in KwaZulu- Natal in 1982 and formed a 100% cover of the river by 1983. An integrated management plan was implemented in 1995 and resulted in a reduction of the weed from a 100% cover to less than 20% cover in 5 years. The keys to success of the water hyacinth integrated management plan, presented here, were finding the source of the weed, mapping the extent of the water hyacinth infestation, identifying sources of nutrient pollution, appointing a champion to drive the programme, dividing the river into management units, consultation with interested and affected parties, judicious use of herbicides and biological control and a commitment to follow-up. This study further showed that water hyacinth on the Nseleni and Mposa river systems had a negative impact on the biodiversity of the protected area and the control of water hyacinth resulted in the recovery of the benthic invertebrate, amphibian, reptile, fish and avian fauna. The implementation of this integrated management plan was very cost-effective and serves as a model approach to the control of water hyacinth in both South Africa and the rest of the world.
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Genetic Diversity in an Invasive Clonal Plant? A Historical and Contemporary PerspectiveWeidow, Elliot D 06 August 2018 (has links)
Introduced populations of Eichhornia crassipes (Pontederiaceae) possess extremely low levels of genetic diversity due to severe bottleneck events and clonal reproduction. While populations elsewhere have been well studied, North American populations of E. crassipes remain understudied. We used Amplified Fragment Length Polymorphism markers to assess genetic diversity and population structure in North American E. crassipes populations. Patterns of diversity over the past fifty years were analyzed using herbarium specimens. Furthermore, we sampled populations across the Gulf Coast of the United States throughout a year to determine contemporary genetic diversity and assess potential seasonal effects. Genetic diversity was found to be scant in the United States without population structure, agreeing with previous studies from other regions. Genetic diversity has remained consistently low over the past fifty years despite significant changes in selection pressure. However, evidence for and against population structure between seasons was found and the consequences of this are discussed.
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Termovalorização da biomassa de aguapé (Eichhornia crassipes) através de pirólise em reator forno rotativo / Thermovalorisation of water hyacinth (Eicchornia crassipes) biomass through pyrolysis in rotary kiln reactorCarregosa, Ingred Suellen Carvalho 27 July 2016 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Lignocellulosic biomass use for obtaining biofuels has been showing itself with
much more evidence during these past years through cellulosic ethanol and biooils,
biogases and biochars. Aquatic plants of lignocellulosic basis, Eichhornia
crassipes species, commonly known by water hyacinth, represent a major
environmental problem due to their invasive nature and their high proliferation
rate. In this work we evaluated the possibility of use this biomass source from
pyrolysis in a rotary kilns reactor in three different temperatures. The results
evidence that the major yield of the liquid fraction (bio-oil + acid extract) was
obtained at 500 ºC (42.11%). For 400 ºC and 600 ºC, the biochar and biogas
had major production, 37.78% and 42.36%, respectively. Bio-oils
characterization by GC/MS produced in microscale allowed an investigation
upon the scale-up phenomenon under the bio-oils composition. The results
show that, in qualitative terms, the chemical composition of bio-oils was not
changed, however, at semiquantitative aspect, show they are produced in
distinguish relative percentages. The mainly chemical classes identified in biooils
were: acids, alcohols, phenols and sugar derivatives. Bio-oils showed in
average, 68% of calorific power of the fuels derived from petroleum, glimpsing
enforcement on the energetic area. In the produced biochars, with yields
between 37% and 26%, the increase on pyrolysis temperature has provided an
increase upon carbon concentration, and a decreasing upon the hydrogen and
oxygen concentrations, reflecting in high aromaticity of the materials. These
materials ware tested in some aspects about the soils management, nutritional
function and water retention. In view of this, the water hyacinth pyrolysis has
associated sustainability concepts and green chemistry, putting concepts of
renewable energetic sources together and glimpsing an environmental
problems inhibition, to offer an alternative to the 2nd generation of bio-fuels
production. / O uso de biomassas lignocelulósicas para a obtenção de biocombustíveis
apresenta-se com muito mais evidência nos últimos anos através do etanol
celulósico e de bio-óleos, biogás e biocarvão. As plantas aquáticas de base
lignocelulósica da espécie Eichhornia crassipes, popularmente conhecida por
aguapé, representam um grande problema ambiental devido ao seu caráter
invasor e sua alta taxa de proliferação. Neste trabalho avaliou-se a
possibilidade de aproveitamento dessa fonte de biomassa a partir do processo
de pirólise em um reator cilindro rotativo em três diferentes temperaturas. Os
resultados demonstraram que o maior rendimento da fração líquida (bio-óleo +
extrato ácido) foi obtido a 500 ºC (42,11%). Para as temperaturas de 400 e 600
ºC, o biocarvão e o biogás tiveram maior produção, 37,78% e 42,36%,
respectivamente. A caracterização por CG/EM dos bio-óleos produzidos em
microescala permitiram investigar o efeito de scale-up sob a composição dos
bio-óleos. Os resultados mostraram que em termos qualitativos, a composição
química dos bio-óleos não foi alterada, no entanto, no aspecto semiquantitativo
mostraram que são produzidos em percentuais relativos distintos. As principais
classes químicas identificadas nos bio-óleos foram: ácidos, álcoois, fenóis e
derivados de açúcares. Os bio-óleos apresentaram em média 68% do poder
calorífico do combustível derivado de petróleo, vislumbrando uma aplicação na
área energética. Nos biocarvões produzidos, com rendimento variando de 37%
a 26%, o aumento da temperatura de pirólise proporcionou um aumento na
concentração de C, e uma diminuição nas concentrações de H e O, refletindo
em maior aromaticidade dos materiais. Estes materiais foram testados sob
alguns aspectos quanto ao manejo de solos, função nutricional e retenção de
água. À vista disto, a pirólise de aguapé relacionou conceitos de
sustentabilidade e química verde, unindo o conceito de fontes de energias
renováveis com a inibição de problemas de cunho ambientais, ao oferecer uma
biomassa alternativa para a produção de biocombustíveis de 2ª geração.
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Avaliação da influência dos macronutrientes na bioacumulação do chumbo pela Eichhornia crassipes / Evaluation of the influence of macronutrients in the bioaccumulation of lead by Eichhornia crassipesOliveira, Ana Paula de 16 February 2012 (has links)
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Previous issue date: 2012-02-16 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The main objective of this study was to verify the influence of the macronutrient phosphorus in the lead bioaccumulation process, using the living aquatic macrophyte Eicchornia crassipes. In addition, the removal capacity of lead ions and some nutrients such as P, K, Ca and Fe, by the E. crassipes was verified, obtaining also information on how these are distributed within two compartiments of the plant: roots and leaves. For this, a set of metal removal/bioaccumulation experiments, in batch mode, was performed for different concentration ranges of metal and nutrients in hydroponic conditions.
Several 5 L growing solutions based on the set of macro and micronutrients specified by Clark as being adequate to cultivate plants in hydroponic conditions were prepared, containing a mixture of lead (0, 5, 10, 15 and 20 mg L-1) and phosphorus (once, twice, four and eight times of 3,2 mg L-1) concentrations among other constant essential nutrient ones. At a greenhouse and using several 8 L containers approximately 80 g of living and healthy E. crassipes aquatic macrophytes were growded in each type of 5 L growing solution, restoring its former hydroponic and metal concentration condition at each two days time interval as well as monitoring the plant weight, the aqueous medium temperature and the pH values. After predefined collection time (2, 4, 8, 16 and 32 d), samples of growing solutions and plants were separated and measured some physico-chemical parameters and then stored in plastic bags for posterior analysis.
Analysis of initial and residual concentrations of lead and nutrients available in the metal-doping Clark growing solutions as well as bioaccumalated metal concentrations in the dried plant samples (roots and leaves) were performed by SR-TXRF technique, except for phosphorus concentrations which were determined by a colorimetric method. According to the TXRF results, the adsorption/accumulation of lead ions in roots and leaves of the Eichhornia crassipes was slightly favoured by the presence of high phosphorus concentrations in the metal-doping Clark growing solutions. It can be noticed that the lead removal by roots is a quit process, occurring basically a high lead adsorption in the first days, whereas the lead bioaccumulation in leaves is a low process due to ocurr a low transportation rate of nutrients for aerial parts of the aquatic plant. Beside this, high lead concentrations in metal-doping Clark solutions have negatively influenced the accumulation of phosphorous in leaves as well as a low phosphorous adsorption in roots, suggesting that there is a detrimental effect on sorption and transport of phosphourous to the leaves by the presence of lead ions.
On the other hand, it was observed a high systematically increasing of potassium concentration in roots whereas a reduction on potassium ones is occurring in leaves due to the presence of lead ions, suggesting that there is a migration process of potassium from leaves to roots. It could be occurring by different possible processes such as potassium complexation in roots or occupation of lead sites by potassium during the transportation of lead to aerial parts, reducing the potassium concentration in leaves. Further nutrient and metal adsorption/bioaccumulation experiments are necessary to understand better the translocation and accumulation process of nutrients such as phosphorus and potassium when lead ions are being adsorbed and transported within the internal structure of the aquatic plant. / O objetivo principal do trabalho foi verificar a influência do macronutriente fósforo no processo de bioacumulação do chumbo, utilizando a macrófita aquática Eicchornia crassipes viva. Além disso, verificou-se a capacidade de remoção de íons chumbo e alguns nutrientes como o P, K, Ca e Fe, pela E. crassipes, obtendo-se também informações de como estes são distribuídos dentro de dois compartimentos da planta: raízes e folhas. Para tanto, foi realizado um conjunto de experimentos de remoção/bioacumulação de metal, em batelada, para diferentes faixas de concentração de metal e nutrientes em condições hidropônicas.
Foram preparadas várias soluções de cultivo com base no conjunto de macro e micronutrientes especificado por Clark como sendo adequado para cultivar plantas em condições de hidroponia, contendo uma mistura de chumbo (0, 5, 10, 15 e 20 mg L-1) e fósforo (uma, duas, quatro e oito vezes 3,2 mg L-1) entre outros nutrientes fundamentais em concentrações constantes. Em uma estufa e usando vários recipientes com capacidade de 8 L, aproximadamente 80 g da macrófita aquática E. crassipes viva e saudável, foram colocadas a crescer em 5 L de cada tipo de solução de crescimento, restaurando-se as condições iniciais hidropônicas e de concentração de metal a cada dois dias, bem como monitorando o peso da planta, a temperatura do meio aquoso e os valores de pH. Após o tempo de cultivo pré-definido (2, 4, 8, 16 e 32 d), amostras de solução de cultivo e planta foram separadas, medidos alguns parâmetros físico-químicos e armazenadas em sacos plásticos para posterior análise.
Análises das concentrações inicial e residual de chumbo e de nutrientes disponíveis na solução de cultivo de Clark contendo metal, assim como concentrações de metal bioacumuladas nas amostras de planta seca (raízes e folhas), foram realizadas pela técnica SR-TXRF, exceto para as concentrações de fósforo, que foram determinadas por um método colorimétrico. De acordo com os resultados da TXRF, a adsorção/acumulação de íons de chumbo nas raízes e folhas da Eichhornia crassipes foi levemente favorecida pela presença de altas concentrações de fósforo nas soluções de cultivo de Clark contendo metal. Pode-se notar que a remoção de chumbo pelas raízes é um processo rápido, ocorrendo basicamente uma alta adsorção de chumbo nos primeiros dias, enquanto que a bioacumulação de chumbo nas folhas é um processo lento devido à ocorrência de uma baixa taxa de transporte de nutrientes para a parte aérea da planta aquática. Além disso, altas concentrações de chumbo na solução de Clark podem ter influenciado negativamente o acúmulo de fósforo nas folhas, bem como uma baixa adsorção de fósforo nas raízes, sugerindo que há uma relação prejudicial na adsorção de fósforo e seu transporte para as folhas pela presença de íons de chumbo.
Por outro lado, observou-se um aumento sistemático na concentração de potássio nas raízes e redução na quantidade de potássio nas folhas devido à presença de íons de chumbo, sugerindo que há um processo de migração de potássio das folhas para as raízes. Isto pode ocorrer por diferentes processos, tais como a complexação de potássio nas raízes ou a ocupação de sítios de chumbo pelo potássio durante o transporte de metal para a parte aérea, reduzindo a concentração de potássio nas folhas. No entanto, são necessários mais experimentos de adsorção/bioacumulação de nutrientes e metal para melhor entendimento do processo de translocação e acumulação de nutrientes, como fósforo e potássio, quando íons de chumbo estão sendo adsorvidos e transportados dentro da estrutura interna da planta aquática.
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Tratamento de efluente industrial de fecularia utilizando macrófita aquática Eichhornia crassipes e coagulante natural / Residuary water treatment of fecularia by means aquatic macrophyte Eichhornia crassipes and coagulants naturalLied, Eduardo Borges 24 February 2012 (has links)
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Previous issue date: 2012-02-24 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The cassava processing industry, especially potato starch, have a high pollution potential due to the release of their effluents on aquatic ecosystems. Among the main characteristics of this effluent highlights the high organic load and the presence of cyanide ion. The treatment of wastewater from potato starch has been done predominantly by treatment ponds. However, this type of system has limitations for wastewater treatment with the presence of cyanide. The cyanide ion is toxic to micro-organisms, and at certain concentrations the effect is significant, compromising both the removal of cyanide itself as other biodegradable compounds. In this context the present study evaluated the efficiency of starch factory effluent treatment by coagulation / flocculation, employing for that seed extracts of Moringa oleifera (M.O.) as a natural coagulant, as well as the use of the aquatic macrophyte Eichhornia crassipes as natural adsorbent. In the first stage of treatment, represented by the tests of coagulation/flocculation was used the methodology of experimental planning Central Composite Rotatable Design (DCCR). The variables studied were of the M.O. and concentration of salt solution of sodium chloride (NaCl). The test conditions were the following: fast mixing speed (VMR) of 100 rpm, mixing time (TMR) of 2 min; slow speed mixing (VML) of 20 rpm, mixing time (TML) 10 min, the settling time was 60 min. The response variables analyzed in this phase were: turbidity and color, COD and cyanide ion. The operating conditions were optimized: concentration M.O. of 2484 mg L-1 and salt concentration of 0.9 mol L-1. Under these conditions it was possible to remove 89.16% of Turbidity, 54.43% of apparent color, 66.39% of COD and 9.9% of cyanide ion. Given the low efficiency of removal of cyanide ion by coagulation is started for a subsequent treatment. For this, we adopted a treatment by batch adsorption using dry biomass of the aquatic macrophyte Eichhornia crassipes as an adsorbent. For the purpose of a further investigation was used a synthetic solution cyanide (NaCN solution). The best operating conditions of pH, adsorbent dosage and contact time were 2.0, 2.0 g L-1 and 20 min, respectively. By simulating a test combined coagulation/flocculation/adsorption with the effluent of cassava industry to greater removal of cyanide ion fit the sample with pH adjustment (2.0), removing around 31%, proving the thesis of the preliminary tests indicated for tests with a solution of sodium cyanide. / As indústrias de processamento de mandioca, especialmente as fecularias, apresentam alto potencial poluidor devido ao lançamento de seus efluentes sobre os ecossistemas aquáticos. Dentre as principais características deste efluente destaca-se a alta carga orgânica e a presença do íon cianeto. O tratamento das águas residuárias de fecularias vem sendo feito predominantemente por lagoas de tratamento. No entanto, esse tipo de sistema de tratamento apresenta limitações para efluentes com presença de cianetos. O íon cianeto é tóxico aos micro-organismos, sendo que em certas concentrações a influência é bastante significativa, comprometendo tanto a remoção do próprio cianeto como de outros compostos biodegradáveis. Neste contexto o presente estudo avaliou a eficiência do tratamento de efluentes de fecularia por coagulação/floculação, para isso empregando extratos de sementes de Moringa oleifera (MO) como coagulante natural, bem como o uso da macrófita aquática Eichhornia crassipes como adsorvente natural. Na primeira etapa do tratamento, representado pelos ensaios de coagulação/floculação foi utilizada a metodologia do planejamento experimental do tipo Delineamento Composto Central Rotacional (DCCR). As variáveis estudadas foram: concentração de MO e concentração da solução salina de cloreto de sódio (NaCl). As condições de ensaio foram as seguintes: velocidade de mistura rápida (VMR) de 100 rpm, com tempo de mistura (TMR) de 2 min; velocidade de mistura lenta (VML) de 20 rpm, com tempo de mistura (TML) de 10 min; o tempo de sedimentação foi de 60 minutos. As variáveis de resposta analisadas nesta etapa foram: Turbidez, Cor Aparente, DQO e Íon Cianeto. As condições operacionais otimizadas foram: concentração de MO de 2484 mg L-1 e concentração salina de 0,9 mol L-1. Nestas condições foi possível remover 89,16% de turbidez, 54,43% de cor aparente, 66,39% de DQO e 9,9% de íon cianeto. Em face da baixa eficiência de remoção de íon cianeto por coagulação partiu-se para um tratamento subsequente. Para isso, adotou-se um tratamento por adsorção em batelada utilizando a biomassa seca da macrófita aquática Eichhornia crassipes como adsorvente. Para efeitos de uma melhor investigação utilizou-se uma solução sintética de cianeto (solução de NaCN). As melhores condições operacionais de pH, dosagem de adsorvente e tempo de contato foram 2,0; 2,0 g L-1 e 20 min, respectivamente. Ao simular um ensaio combinado de coagulação/floculação/adsorção com o efluente bruto de fecularia a maior remoção de íon cianeto coube a amostra com ajuste de pH (2,0), remoção em torno de 31%, comprovando a tese dos ensaios preliminares indicados pelos testes com a solução de cianeto de sódio.
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Uso de duas espécies de macrófitas aquáticas, Eichhornia crassipes e Pistia stratiotes em tratamento de resíduos de cervejaria na cidade de Toledo/PR / Use of two species of aquatic macrophytes Eichhornia crassipes and Pistia stratiotes for treatment of waste brewery in the city of Toledo / PRSales, Cristina Viana 23 August 2011 (has links)
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Previous issue date: 2011-08-23 / The accumulation and deposition of high concentrations of organic matter cause the eutrophication of aquatic environments, and a sustainable alternative to the removal of these compounds is phytoremediation. This study evaluated the potential of two floating aquatic macrophytes, Eichhornia crassipes and Pistia stratiotes in the treatment of brewery wastewater. The treatment system consisted of eight experimental units, and the experimental design 2 treatments and 4 pseudoréplicas, each treatment was coupled to a mechanical filter in closed circulation system. We analyzed the parameters temperature, electrical conductivity, pH, dissolved oxygen, turbidity, COD, total phosphorus, nitrogen, nitrite and nitrate, and measure the biomass of macrophytes, the experiment lasted 21 days, with collections made weekly. Statistical analysis showed no statistical difference between treatments for the reduction of nutrients, however the two species E. crassipes and P. statiotes been proven effective in removing these nutrients. As for weight gain, E. crassipes had a higher growth compared to P. stratiotes. The use of phytoremediation is recommended for the treatment of brewery effluents due to low cost, easy maintenance and efficiency of aquatic macrophytes in removing nutrients that cause eutrophication of aquatic environments. / O acúmulo e deposição de elevadas concentrações de matéria orgânica provocam a eutrofização de ambientes aquáticos, e uma alternativa sustentável para a retirada destes compostos é a fitorremediação. Neste estudo avaliou-se o potencial de duas espécies de macrófitas aquáticas flutuantes, Eichhornia crassipes e Pistia stratiotes, no tratamento de efluente de cervejaria. O sistema de tratamento foi constituído de 8 unidades experimentais, sendo o delineamento experimental de 2 tratamentos com 4 pseudoréplicas, cada tratamento foi acoplado a um filtro mecânico, em sistema de circulação fechado. Foram analisados as variáveis temperatura, condutividade elétrica, pH, oxigênio dissolvido, turbidez, DQO, fósforo total, nitrogênio, nitrito e nitrato, e medida a biomassa das macrófitas aquáticas, o experimento teve duração de 21 dias, sendo as coletas feitas semanalmente. O estudo estatístico mostrou que não houve diferença estatística entre os tratamentos quanto à redução de nutrientes, no entanto as duas espécies E. crassipes e P. statiotes se mostraram eficazes na remoção desses nutrientes. Quanto ao ganho de peso, E. crassipes teve maior crescimento comparado a P. stratiotes. O uso da fitorremediação é recomendável para o tratamento de efluentes de cervejaria devido ao baixo custo, a fácil manutenção e a eficiência das macrófitas aquáticas na remoção de nutrientes que causam a eutrofização de ambientes aquáticos.
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Estudo da bioacumulação de cobre e chumbo pela macrófita aquática Eicchornia crassipes em solução hidropônica / Bioaccumulation study of copper and lead by the Eicchornia crassipes in hydroponic solutionSzymanski, Nayara 11 February 2011 (has links)
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Previous issue date: 2011-02-11 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Aquatic macrophytes are known to remove heavy metals from the surface by adsorption or absorption and incorporate them into systems, in different ways. The main objective of this work is to study the multicomponent bioaccumulation of copper and lead by the living aquatic macrophyte Eicchornia crassipes. The experiments were performed in triplicate using about 30g healthy young plants and 5L Clark s hydroponic solution doped with non-toxic concentration of copper and lead metals combined. All experiments have been carried out in a greenhouse, for 20 days, monitoring the loss of water volume and adding deionized water as it was needed. Samples were performed in predetermined collection times (2, 4, 7, 12 and 20 days) to determined the metal content by the synchrotron radiation reflection X-ray fluorescence technique (SR-TXRF), and the measurements of SR-TXRF were performed at the Brazilian Light Synchrotron Laboratory (LNLS). It was observed that at least 90% metal concentration was removed of all experiments by bioaccumulation process, this indicates that the adsorption process is quick in roots, but slow if accumulation process takes place in aerial parts. The kinetics of biosorption that better fits the experimental data was Irreversible Langmuir for Cu and Pb, and Pseudo-first order and Pseudo-second order for Cu and Pb, respectively at the multicomponent experiment. / Macrófitas aquáticas são conhecidas por removerem metais pesados pela superfície, por adsorção ou absorção, e incorporá-los em seu sistema de diversas formas. O objetivo principal deste trabalho é estudar a remoção multicomponente de cobre e chumbo pela macrófita aquática flutuante Eicchornia crassipes viva. Experimentos foram realizados em triplicata, utilizando em média 30 gramas de plantas, jovens e sadias em 5L de solução hidropônica de Clark dosada a uma concentração não tóxica de metais cobre e chumbo em três combinações. Todos os experimentos foram conduzidos em estufa externa, durante 20 dias, monitorando-se o nível do volume de água pela adição de água deionizada quando necessário. Coletas de amostras foram feitas em tempos pré-determinados (2, 4, 7, 12 e 20 dias). A determinação das quantidades de metais foi feita utilizando-se da técnica de espectroscopia de Raios-X por Reflexão Total (SR-TXRF), e as medidas de SR-TXRF foram efetuadas no Laboratório Nacional de Luz Síncrotron (LNLS). Foi observada redução de até 90% nos valores de concentração dos metais, nos experimentos realizados, indicando que cobre e chumbo foram removidos pela macrófita pelo processo de bioacumulação, ou seja, rápida adsorção pelas raízes e um lento processo de acumulação nas partes aéreas. As cinéticas de biossorção que melhor ajustaram-se aos dados experimentais foram de Langmuir Irreversível para Cu e Pb, e de Pseudo-primeira ordem e Pseudo-segunda ordem para Cu e Pb, respectivamente no experimento multicomponente.
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Estudio de un biosistema integrado para el postratamiento de las aguas residuales del café utilizando macrófitas acuáticasRODRÍGUEZ VALENCIA, NELSON 02 April 2009 (has links)
El objetivo principal de la presente investigación es la generación de la información necesaria para el diseño de un biosistema integrado que utilice macrófitas para el postratamiento de las aguas mieles del café, buscando que sus efluentes generen el menor impacto negativo posible sobre el ecosistema acuático cafetero, presentando alternativas viables, desde el punto de vista técnico, económico, ambiental y social, para la adecuada disposición de la biomasa generada durante el proceso de depuración.
En un primer ensayo, que constó de 18 tratamientos, se determinó el efecto de la concentración, en términos de DQO, de las aguas mieles del café tratadas mediante digestión anaerobia sobre el desempeño de sistemas acuáticos de tratamiento, a escala de mesocosmos, sembrados con las especies flotantes Eichhornia crassipes, Pistia stratiotes, Salvinia auriculata y la especie emergente Typha angustifolia, evaluando la remoción de los parámetros físico-químicos DQO, DBO5, ST, SST, NT, PT, K, S y del grupo de bacterias Coliformes.
En un segundo ensayo, que constó de 24 tratamientos, se determinó el efecto de la carga orgánica de los efluentes de los sistemas anaerobios de tratamiento de las aguas mieles del café sobre el desempeño de sistemas acuáticos de tratamiento, sembrados con las mismas especies de plantas y determinando los mismos parámetros de remoción evaluados en el ensayo 1.
Considerando el desempeño de las 4 especies acuáticas en la remoción de los parámetros DBO5, SST, NT, PT y K (medida como mg/m2-d) en los 2 ensayos evaluados, se determinó que la mejor especie para el postratamiento de las aguas mieles del café fue E. crassipes, seguida de P. stratiotes, T. angustifolia y S. auriculata.
En un tercer ensayo, se evaluó el efecto del monocultivo vs la combinación de especies, en sistemas acuáticos para el postratamiento de las aguas mieles del café. / Rodríguez Valencia, N. (2009). Estudio de un biosistema integrado para el postratamiento de las aguas residuales del café utilizando macrófitas acuáticas [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/4342
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