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Investigating variability of biogenic gas dynamics in peat soils using high temporal frequency hydrogeophysical methodsUnknown Date (has links)
Peat soils are known to be a significant source of atmospheric greenhouse gasses. However, the releases of methane and carbon dioxide gasses from peat soils are currently not well understood, particularly since the timing of the releases are poorly constrained. Furthermore, most research work performed on peatlands has been focused on temperate to sub-arctic peatlands, while recent works have suggested that gas production rates from low-latitude peat soils are higher than those from colder climates. The purpose of the work proposed here is to introduce an autonomous Ground Penetrating Radar (GPR) method for investigating the timing of gas releases from peat soils at the lab scale utilizing samples originating from Maine and the Florida Everglades, and at the field scale in a Maine peatland. Geophysical data are supported by direct gas flux measurements using the flux chamber method enhanced by timelapse photography, and terrestrial LiDAR (TLS) monitoring surface deformation. / by William J. Wright. / Thesis (M.S.)--Florida Atlantic University, 2013. / Includes bibliography. / Mode of access: World Wide Web. / System requirements: Adobe Reader.
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Avaliação da eficiência de uma zona alagadiça (wetland) no controle da poluição por metais pesados: o caso da Plumbum em Santo Amaro da Purificação/BA. / Investigation on the wetland efficiency for the control pollution of heavy metals: the specific case of "Plumbum" at Santo Amaro da Purificação/Bahia.Anjos, José Ângelo Sebastião Araujo dos 24 February 2003 (has links)
Esta pesquisa teve o objetivo de avaliar a eficiência de uma zona alagadiça (wertland) que ocorre nas dependências de uma usina situada em Santo Amaro da Purificação, Bahia, como medida de controle da contaminação proveniente de um barramento de escória contaminada por metais pesados. Inicialmente, foi proposto um levantamento anual com amostragens semanais das águas pluviais e superficiais da zona alagadiça, com o intuito de avaliar a eficiência da zona alagadiça, por meio do levantamento das concentrações dos metais oriundos dos processos de lixiviação e/ou solubilização da escória nos seus pontos de entrada e saída do sistema alagado e, concentrações e potencial disponibilidade dos metais retidos nos sedimentos da zona alagadiça. Foram selecionados os seguintes parâmetros: para as águas pluviais o pH e o volume da chuva; para as águas superficiais as concentrações dos metais Chumbo (Pb), Cádmio (Cd), Zinco (Zn), Cobre (Cu), Alumínio (Al), Manganês (Mn), Ferro (Fe), Magnésio (Mg) e Cálcio (Ca) e os parâmetros de suporte pH, Eh, condutividade, Oxigênio Dissolvido (OD) e temperatura. Para o solo e sedimento da zona alagadiça as concentrações dos metais Pb, Cd, Zn e Cu e, determinação por análise por extração seqüencial do total removido pelo sistema nas suas diversas fases e a potencial disponibilidade dos metais pesados. Todavia, uma modificação da estratégia de pesquisa teve que ser feita em função de uma decisão judicial que determinou o recobrimento da escória e do ponto de entrada da zona alagadiça. Em função do ocorrido, a pesquisa foi dividida em três etapas considerando os levantamentos efetuados antes, durante e depois do recobrimento. Os dados levantados nos cinco meses antes do recobrimento mostraram que os metais cádmio, chumbo, cobre e zinco estão sendo retidos pela zona alagadiça e, que este sistema foi eficiência de 100% para os metais cobre e zinco, 82% para o chumbo e 73% para o cádmio. Os parâmetros de suporte que influenciam a remoção destes metais foram o pH, entre neutro a alcalino, e Eh, na faixa de oxidação das águas superficiais, além da alta capacidade de troca catiônica da montmorilonita presente no sedimento. Quanto ao potencial de disponibilidade dos metais, cádmio, chumbo e zinco apresentam valores elevados, enquanto o cobre encontra-se preferencialmente concentrado na fase residual. A segunda etapa do levantamento realizada durante o recobrimento da escória demonstrou que ocorreu pouca migração dos metais da zona alagadiça, embora a empresa não tenha obedecido as normas técnicas para o recobrimento da escória. Na terceira etapa foi realizado levantamento na saída da zona alagadiça e da drenagem próxima ao rio Subaé. As análises levantadas demonstraram a grande disponibilidade do cádmio no sistema alagado, este mecanismo foi acionado a partir da erosão do solo contaminado disposto sobre a escória e a grande solubilidade do cádmio. Desta forma pode-se conclui que as zonas alagadiças estão sendo eficientes na retenção dos metais. A redução de sua área é indesejável, pois tende a diminuir sua eficiência, como sistema de controle da poluição das águas superficiais, recomenda-se a construção de nova zona alagadiça a jusante da existem. / A lead ore smaller which operated from 1960 to 1993 in Santo Amaro da Purificação, Bahia State, disposed of 490,000 tons of slag in a landfill situated in the situated in the industrial site. Earthworks formed a man-made wetland downstream of the slag landfill, which acted as a metal retaining systems, thus preventing further water pollution. This research aimed at investigating the efficiency of this wetland as a water pollution control system. The research plan scheduled weekly samplings of rainfall, rainwater pH and water runoff in two points corresponding to the input and the output of the wetland for determination of metals concentration (Pb, Cd, Cu, Zn, Al, Mn, Fe, Mg, Ca), as well as water pH, Eh, conductivity, temperature and dissolved oxygen (OD). In addition, soil and sediment in the wetland were sampled and analyzed for Pb, Cd, Zn and Cu by sequential extraction methods. However, a Court ruling following a lawsuit for environmental damage led to the slag being covered by clayish soil weeks after sampling began. As a consequence, the point where waters entered the wetlands has been covered. Hence, sampling in this point has been discontinued and a new sampling point was established downstream of the wetland, at a point where its waters flow into a river. Results showed that before cover-up, Pb, Cd, Cu and Zn were being retained in the wetland at rates reaching 100% for Cu and Zn, 82% for Pb and 73% for Cd. After cover-up, Cd was being released into the waters. Sequential extraction showed that only Cu is not available for leaching, since it is mostly concentrated in the insoluble phase. On the other hand, Pb, Cd and Zn are potentially available, thus could re-enter other media if wetland is disturbed. The wetland acts as an efficient device for retaining metals because of near neutral water pH, oxidizing water Eh, and the existence of montmorillonite clay in the sediments, which features high cationic exchange capacity. It is concluded that this involuntary wetland has been working, as an efficient system for water pollution control. The reduction in its size, due to the cover-up activities, is undesirable. Hence, a new constructed wetland is proposed downstream of the existing one. Then, we can end that the wetland of Plumbum this being efficient in the control of the metals, from when interferences anthropogenetic that maximize the capacity of support of this system dont happen.
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Establishing Spatiotemporal Linkages Between Hydrological and Soil Physical Characteristics and Vegetation on an Ecological Preserve: Boca Raton, FL.Unknown Date (has links)
In recent decades, ecohydrology has received renewed attention because of the impacts of groundwater withdrawal on ecosystems. Growing population and urban expansion in Palm Beach County, FL. place pressure to eradicate natural areas, such as Florida scrub habitats, and increase groundwater withdrawal. This study presents preliminary results of soil and hydrological characterization of an ecological preserve surrounded by changing land use. Soil moisture and water levels were monitored to assess the effects of precipitation as influenced by plants and soil analysis determined the suitability of current soil conditions for hosting native vegetation habitats. Hydrologic and soil conditions on the preserve fall within values expected for native Florida scrub habitats. Hydrologic response to precipitation varied due to factors including antecedent conditions and vegetation types. These results provide a better understanding of the interactions between soil proper ties, hydrologic cycle, and plants, and assist with establishing a baseline to monitor changes over time. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2015. / FAU Electronic Theses and Dissertations Collection
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Consumptive effects of predatory fish reduce wetland crayfish (Procambarus spp.) recruitment and drive species turnoverUnknown Date (has links)
Trade-offs in traits conferring success in permanent and ephemeral habitats are often at odds with few species being able to persist in both types of environments. I examined the effect of sunfish predators on two species of south Florida crayfish to establish the mechanism that limits one species, Procambarus alleni, to short-hydroperiod environments. The crayfish assemblage response to a gradient of sunfish predators and the effect of predation on P. fallax alone was examined. I also examined the effects of sunfish on crayfish growth and quantified activity levels and risky behaviors of both crayfish species. P. alleni dominated at low sunfish densities but dominance shifted with increasing sunfish density. P. alleni was more active and likely to initiate risky behaviors, suggesting that sunfish predators remove the more active P. alleni, reducing their numbers disproportionally to those of P. fallax and allowing P. fallax to dominate crayfish assemblages in long-hydroperiod wetlands. / by Christopher M. Kellogg. / Thesis (M.S.)--Florida Atlantic University, 2011. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2011. Mode of access: World Wide Web.
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Mechanisms that generate resource pulses and drive wading bird nesting in a fluctuating wetlandUnknown Date (has links)
Variation in the seasonal water level fluctuations of tropical and subtropical wetlands controls the production and concentration of aquatic fauna that support breeding wading birds. However, little is known about how particular components of the annual hydrologic cycle affect processes that control food availability and reproduction. This thesis identifies specific mechanisms responsible for transforming wet season prey standing stock into dry season prey concentrations, links landscape hydrological patterns to wading bird nesting, and presents a predictive model of Wood Stork nesting. I examined the supoort for several a priori hypotheses of factors affecting wading bird prey concentrations and wading bird nest effort. Factors affecting the concentration and vulnerability of prey were important for transferring secondary production to higher trophic levels. Receding water levels, microtopographic variation, and high standing stocks of prey were critical for generating pulses of food availabiltiy to meet the high energy requirements of breeding predatory birds. / by Bryan A. Botson. / Thesis (M.S.)--Florida Atlantic University, 2012 / Includes bibliography. / Mode of access: World Wide Web. / System requirements: Adobe Reader.
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Diet variation and the consumptive effects of native centrarchids on benthic macroinvertebrates in wetlandsUnknown Date (has links)
Fish predation can have structuring effects in aquatic communities, but the most important fish predators are not always immediately obvious. Generalist fish predators often occupy similar habitats and consume similar prey making determination of their consumptive impacts difficult. Understanding these consumptive impacts is important for understanding complex wetland food webs. I collected warmouth (Lepomis gulosus), bluespotted sunfish (Enneacanthus gloriosus), and dollar sunfish (Lepomis marginatus) in two seasons from sloughs for both diet and bioenergetics analysis. Macroinvertebrates dominated diets of the three species, and nonparametric analyses revealed evidence of diet ontogeny in warmouth and potential competition for prey items among gape-matched individuals. Bioenergetics modeling revealed high levels of macroinvertebrate comsumption by these species relative to macroinvertebrate reproductive output suggesting that when combined with other sources of mortality, consumptive pressures placed by sunfish on benthic macroinvertebrates may be quite large. / by Jacob Bransky. / Thesis (M.S.)--Florida Atlantic University, 2012. / Includes bibliography. / Mode of access: World Wide Web. / System requirements: Adobe Reader.
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Bio-physical controls on tidal network geomorphologyBelliard, Jean-Philippe January 2014 (has links)
Looking over a tidal wetland, the tidal network characterised by its intricate system of bifurcating, blind-ended tidal courses clearly stands out from the overall landscape. This tidal landform exerts a fundamental control on the morphology and ecology within the tidal environment. With today’s recognition of the ecological, economical and societal values provided by tidal wetlands, which has been notably reflected in the development of restoration management strategies across Europe and USA, there is a need to fully understand the nature and development of tidal networks as well as their relationships with associated landforms and biotic components (e.g. vegetation), to eventually guarantee the success of current and future restoration practices. Accordingly, this research aims to bring further insights into the bio-physical controls on the geomorphology of tidal networks. To this end, a combination of remote sensing, modelling and field activities was employed. A geo-spatial analysis was performed at Queen Mary, University of London (UK), to address the variability of tidal network patterns. A series of network scale morphometric variables was extracted using airborne LiDAR data among selected tidal networks across the UK depicting different planview morphologies, and supplemented with the collection of corresponding marsh scale environmental variables from published sources. Multivariate statistics were then performed to characterise the variability of tidal network patterns and identify the inherent environmental controls. The analysis has revealed that every network type can be characterised based upon measures of network size and complexity, with each network pattern depicting proper morphometric aspects. Particularly, the stream Strahler order and the median depth of the network main channel have the highest discriminating weight on the patterns investigated. High correlation between the latter variable and network main channel width has revealed that linear, linear-dendritic and dendritic networks followed a transitional gradient in their aspect ratio approximated by a power law and thus are seen to depict similar erosional processes. To the contrary, meandering networks clearly depart from this relationship, and show particular segregation in their aspect ratios with respect to dendritic networks. Globally, differentiation on network morphometric properties has been linked to environmental conditions specific to the marsh physiographic setting within which a tidal network develops. Conceptually, tidal networks seem to adapt to marsh environmental conditions by adopting suitable morphologies to drain their tidal basin effectively. An eco-geomorphic modelling framework was developed at University of Trento (Italy), to address tidal network morphological development. In line with current theories as well as modelling advances and challenges in the field of tidal network ontogeny, emphasis was thus placed on the investigation of tidal channel formation and evolution in progressive marsh accretional context. Under these environmental conditions, tidal network development can be ascribed to the combination of two channel-forming processes: channel initiation results from bottom incisions in regions where topographic depressions occur; channel elaboration results from differential deposition, contributing to the deepening of the tidal channels relative to the adjacent marsh platform. Further evolutionary stages including channel reduction proceed from the horizontal progradation of the marsh platform which may lead eventually to channel infilling. Moreover, both qualitative and quantitative results allude to an acceleration of the morphological development of the synthetic tidal networks with increasing sediment supply. These different observations thus emphasise the prevalence of depositional processes in shaping tidal channels. In a second stage, the investigation was extended to the role of the initial tidal flat morphology as an inherent control on tidal network development, by considering different scenarios of topographic perturbations, which has revealed its legacy on tidal network morphological features. Modelling experiments have also acknowledged salt marsh macrophytes as a potential control on network evolution depending on their biomass distribution within the tidal frame. However, tidal channel morphodynamcis appears to be sensitive to the way biomass growth is mathematically parameterised in the model. In view of the current challenges in transcribing mathematically such a dynamic process and the relevance of bio-physical interactions in driving salt marsh and tidal network evolution, a field survey was conducted in a temperate salt marsh in the Netherlands, as part of the mobility to UNESCO-IHE (Netherlands) in partnership with University of Antwerp (Belgium), to assess vegetation distribution and productivity in the tidal frame. Particularly, emphasis was placed on extending investigations on the possible presence of relationships involving vegetation properties in different climatic and ecological conditions from those characterising these previously documented relationships. Regression analysis has revealed that biomass growth can be expressed as a linear function of marsh relative elevation, providing therefore direct empirical validation for corresponding assumptions reported in the literature and used in the present modelling framework; surprisingly, that increase did not correlate with an increase in species richness and diversity. Analysis of likely associations between vegetation morphometrics and total standing biomass yielded only a single linear relationship linking the latter variable to stem height. In truth, these observations may bear reconsiderations on the global validity of the assumptions used in the formulation of some eco-geomorphic processes which are applied in the study and prediction of wetland resiliency facing climate change.
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Dinâmica, sazonalidade e estrutura da comunidade de aves em uma área úmidaKoury, Helena Ansanello January 2019 (has links)
Orientador: Reginaldo José Donatelli / Resumo: As áreas úmidas têm uma grande importância global e estão sendo altamente degradadas por ações antrópicas. As aves presentes nessas áreas têm sido usadas como indicadores da qualidade ambiental de ecossistemas aquáticos e suas populações são sensíveis as mínimas alterações no habitat. Elas representam um grupo expressivo na composição dos ecossistemas aquáticos, exercendo um impacto ecológico considerável. Dessa forma as espécies de aves encontradas em uma área úmida permanente foram utilizadas para avaliar a importância e qualidade desse ambiente, por meio da metodologia de transecto. O presente trabalho teve como objetivo o estudo da dinâmica da avifauna existente na fazenda Itapuã, situada em Gália, São Paulo, além de mostrar a importância de áreas preservadas dentro de propriedades rurais. Foram registradas 169 espécies, das quais 22 foram observadas fora do período amostral, distribuídas em 50 famílias, sendo 30 de aves não-Passeriformes e 20 de Passeriformes. Desse total, 40 espécies são consideras dependentes de áreas úmidas. A diversidade de aves não diferiu entre as estações do ano, porém a composição de espécies foi distinta. Isso poderia ser explicado pelas diferentes exigências das aves bem como as variações ambientais da área e do entorno ao longo do ano. Houve um predomínio de aves insetívoras, como esperado devido à grande riqueza dessa categoria alimentar nos trópicos, bem como uma boa representatividade de frugívoros, o que poderia sugerir indicativo de quali... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Wetlands are of great global importance and are being heavily degraded by human activities. Wetlands birds have been used as indicators of the environmental quality for aquatic ecosystems, being their populations sensitive to minimal changes in habitat. Such group of birds represent an expressive abundance in aquatic ecosystems where they play a considerable ecological role. Therefore, we sought to register and count bird species in a permanent wetland area in order to evaluate the importance and quality of this environment. We used the linear transect methodology to study the dynamics of the wetland birds occurring at Itapuã ranch, located in the municipality of Gália, São Paulo state. Moreover, we sought to verify the importance of wetland areas within rural properties. We recorded 147 species during sample period, being 22 outside this time; the total birds account for 169 species distributed in 50 families, 30 of which were non-Passeriformes and 20 were Passeriformes; 40 of which were considered dependent on wetlands. The weather seasons were similar in relation to bird diversity, but differed in species composition. This can be explained by the different requirements of birds throughout the year as well as the environmental variations during a year. There was a clear predominance of insectivorous birds, as well as a relative representation of frugivorous species; such results may be considered a good indicator of environmental quality. A total of 65 migratory species and... (Complete abstract click electronic access below) / Mestre
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Evaluation des potentialités de traitement par phytoépuration du lisier de porc en région PACA : paramètres chimiques, microbiologiques et macrophytiques / Evaluation of an integrated constructed wetland to manage pig manure under Mediterranean climateNehmtow, Julie 16 December 2015 (has links)
L’objectif de la thèse était de développer un procédé de traitement des lisiers de porc par zone humide artificielle (ZHA) adapté aux contraintes du climat méditerranéen ainsi qu’à celles des éleveurs porcins. Le lisier de porc présentant des teneurs en ammonium (NH4+) toxiques pour les espèces végétales, il a été nécessaire de prétraiter le lisier. Des expérimentations sur le prétraitement du lisier de porc par aération continue (30 jours) à petite (12 litres) et moyenne échelles (300 litres) ont donc été conduites, et ont permis une diminution des concentrations en NH4+ en dessous des seuils de tolérance végétale. Cependant, la volatilisation de l’ammoniac semble avoir été le processus majoritairement à l’origine des abattements observés (phénomène d'ihnibition). Afin d’améliorer la diminution du NH4+, des produits d’ensemencement microbiens commerciaux ont été utilisés sans que leur effet n'ait pu être mis en évidence. Lors des expérimentations à moyenne échelle, le lisier prétraité a été amendé en ZHA (mésocosmes constitués d’un filtre à écoulement vertical suivi d’un filtre à écoulement horizontal). La forte variabilité phénotypique en système expérimental des macrophytes sélectionnés et prélevés dans le milieu naturel environnant (Carex hispida, Typha latifolia, Carex cuprina, Iris pseudacorus, Alisma lanceolatum et Juncus effusus), a été illustrée. Lors des apports en lisier dans la ZHA, les espèces végétales ont répondu différement, soulignant l’intérêt des cortèges multi-spécifiques. Les premiers résultats épuratoires ont été probants. Cependant l’étude des processus épuratoires a mis en lumière la problématique de leur durabilité. / The aim of the thesis was to develop a treatment process of pig manure by constructed wetland (CW) and designed in order to be adapted to the Mediterranean climate constraints and those of pig farmers. However hog manure has concentrations above 2 g.l-1 of ammonium (NH4+), toxic to the plants. It is therefore necessary to establish a slurry pre-treatment step. The thesis has included experiments including pre-treatment of pig slurry by continuous aeration (30 days) to small (12 liters) and medium scale (300 liters). Commercial products for microbial seeding were also used. The results showed that the aeration of pig manure did allow lower concentrations of NH4+ below plant tolerance threshold. However, the ammonia volatilization process appears to be the leading cause behind the observed reductions (inhibition phenomenom). No effect could be demonstrated for microbial treatments. During meso-scale experiments, the CW was amended with the pre-treated slurry (mesocosms made of a vertical flow filter followed by a horizontal flow filter). As a first step, the high phenotypic variability of macrophytes (taken from the natural environment) in experimental system was illustrated and discussed. After manure application, the selected plant species (Carex hispida, Typha latifolia, Carex cuprina Iris pseudacorus, Alisma lanceolatum and Juncus effusus) have presented different responses, emphasizing the importance of multi-species selection for the CW. Finally, the first purifying results were conclusive. However the study of the underlying purifying processes has highlighted the issue of sustainability of these phenomena.
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Uso de sistema wetland construído no pós-tratamento de efluente de curtume / Constructed wetland system use in the tannery industry wastewater post-treatmentZacarkim, Carlos Eduardo 25 September 2006 (has links)
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Previous issue date: 2006-09-25 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / Water contamination with heavy metals is a very important problem in the current world. Occurrence of toxic metals in pond and river water affects the lives of local people that depend upon these water sources for their daily requirements. Chromium is one of the toxic heavy metals, which is released into environment in effluents generated from tanneries and other industries. Conventional chemical methods for removal of toxic metals are ineffective when levels of metals in wastewaters are very low (between 10 - 100 ppm). Therefore, use of low cost, natural resources for removal of metal is being preferred over other conventional methods. Many plants have been known to accumulate heavy metals and other nutrients from contaminated waters and can be exploited for polishing of wastewaters. Aquatic macrophytes have been used during the last two decades for water metal removal competing with other secondary treatments, being the principal mechanism for metal uptake adsorption trough roots. As an alternative method, constructed wetlands have emerged as a viable option for addressing a wide range of water quality problems, especially in treating wastewater effluent. In tropical and subtropical regions, because of its abundance and the large biomass produced, the water hyacinth (Eichhornia crassipes) has been studied especially for this purpose. The main objective of the present study was to evaluate two constructed wetland in greenhouse for treating of tannery wastewater effluent, using two autochthonous floating macrophytes Eicchornia crassipes and Salvinia auriculata in order to remediate the contaminated industrial effluent, under natural conditions. The amount of wastewater generated by a tannery industry is ranged 30-50 L per kg of processed animal skins. Around of 10% of all wastewater effluent correspond to initial stage of animal skin processing into leather and 90% corresponding to intermediate and final process such as washing, neutralization and tinged. This work was performed at a 48-m2 greenhouse constructed in the Toledo Campus of the West Paraná State University, using wastewater effluents from a Tannery industry located in Toledo County. The experiences were carried out for three different hydraulic removal time: 4, 6 and 8 days. At each collection time, physic-chemical parameters such as Oxygen Chemical Demand (OCD), Inorganic Phosphorus and Total Kjeldahl Nitrogen (TKN), pH, Dissolved Oxygen (DO) were determined according to chemical standard methods, and Chromium, Sulfur, Aluminium and Iron total concentrations were calculated by PIXE technique. The second wastewater treatment wetland system working with aquatics plants Salvinia was excluded of these experiences due to tannery wastewaters were along the time in presence of different concentrations of contaminants, showing non-reliable results. Also, tannery wastewaters have shown very high concentrations of sulfur. In such conditions, salvinia species started showing toxicity symptoms and began to develop necrosis. On the other hand, the first wetland system working with the water hyacinth showed high contaminants removal percentages for all evaluated parameters / A quantidade de águas residuárias produzidas por um curtume variam entre 30-50L por quilograma de pele processada. Do total dos efluentes, cerca de 10% correspondem ao estágio inicial de fabricação do couro e o restante remanescente corresponde ? s demais etapas do processo como a neutralização, tintura, lavagem, etc. O uso de wetlands como alternativa no processo de tratamento de águas residuais vem sendo empregado como alternativa, visto a tecnologia e manejo simples e de baixo custo em relação a outros sistemas convencionais que, por apresentarem sistemas sofisticados de tratamento, proporcionam custos elevados. Visto ? problemática ambiental causada pela industria do couro, o presente trabalho avaliou um sistema wetland construído com macrófitas aquáticas flutuantes no pós-tratamento de efluente de um curtume de acabamento. A pesquisa foi realizada entre os dias 09/02 a 05/05/2006 na UNIOESTE/ Campus de Toledo, utilizando efluente proveniente de um curtume de acabamento de couro localizado no município de Toledo - PR, onde a matéria prima é o couro wet-blue. O estudo foi baseado em dois sistemas: um utilizando-se a macrófita Eicchornia crassipes e outro a macrófita Salvinia sp. Os parâmetros avaliados foram: DQO, Nitrogênio Total Kjeldahl NTK, Fosfato Total, pH, O2 Dissolvido, e os íons (Cr, S, Al e Fe). O sistema II, operado com a macrófita Salvinia sp., apresentou problemas em relação a concetração de nutrientes fornecidos pelo efluente do curtume optando-se em operar somente com o Sistema I, onde foram avaliados 3 tempos de detenção hidráulicas (4, 6 e 8 dias). O Sistema I apresentou reduções de 73,41% a 79,91% de DQO, 48,94% a 83,51% de Fósforo total, 59,24% a 67,93% de Nitrogênio total, 73,6% a 87,7% Cromo, 26,5% a 52% de Enxofre, 60 a 78% para o Ferro e 58,5% a 80,4% para o Alumínio. O principal limitante do sistema e o provável responsável pela morte das plantas no sistema II foi o Enxofre. De modo geral, o TDH de 6 dias foi o que apresentou melhores resultados em porcentagens de remoção. O sistema resultados promissores em termos de remoção a baixo custo operacional
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