No description available.

No description available.

No description available.

Thesis (Ph.D)--Civil and Environmental Engineering, Georgia Institute of Technology, 2008. / Committee Chair: Saunders, F. Michael; Committee Member: Huang, Ching-Hua; Committee Member: Hughes, Joseph; Committee Member: Loeffler, Frank; Committee Member: Pullman, Gerald; Committee Member: Spain, Jim. Part of the SMARTech Electronic Thesis and Dissertation Collection.

Orientador: Raoul Henry / Banca: Alaíde Aparecida Gessner / Banca: Evanilde Benedito / Resumo: O objetivo deste estudo foi analisar a composição taxonômica e a densidade de macroinvertebrados associados à macrófita Eichhornia azurea (Swartz) Kunth em seis lagoas laterais ao Rio Paranapanema em sua zona de desembocadura na Represa de Jurumirim - SP. As amostragens foram realizadas em março e agosto de 2009, supostamente meses de estações chuvosa e seca, respectivamente. Em cada uma das seis lagoas, foram selecionados três bancos distintos de E. azurea para coleta do material biológico (macrófita e fauna associada) e medida das variáveis limnológicas: profundidade, transparência, temperatura, pH, condutividade elétrica e concentrações de oxigênio dissolvido e material em suspensão. A amostragem de E. azurea foi realizada com um retângulo de 0,1976 m2, utilizando-se uma tesoura de jardinagem para retirada do material vegetal, que foi lavado em solução de formol e água para remoção dos macroinvertebrados associados. Entre os períodos estudados diferenças significativas (p<0,05) foram encontradas tanto para as variáveis limnológicas, quanto para a densidade de alguns dos taxa de macroinvertebrados. Na comparação das lagoas entre si em março e agosto, com relação as variáveis limnológicas e densidade dos taxa de macroinvertebrados (em níveis de grandes grupos), o Teste Tukey apontou mais diferenças significativas (p<0,05) para março, embora alguns dos taxa de macroinvertebrados associados à E. azurea não tenha apresentado diferença significativa entre as lagoas em nenhum dos períodos amostrados. De acordo com a análise de componentes principais, o pH e oxigênio dissolvido são as variáveis que melhor explicam a ordenação das lagoas nos períodos de estudo. Com relação à fauna associada, em ambos os períodos a classe Insecta foi a mais abundante (com destaque a família Chironomidae), seguida pelo filo Crustacea e pela classe Clitellata... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The aim of this study was to analyze the taxonomic composition and density of macroinvertebrates associated with macrophyte Eichhornia azurea (Swartz) Kunth in six lagoons to the river side Paranapanema in its mouth zone into the Jurumirim Reservoir - SP. Samples were held in March and August 2009, supposedly months of rainy and dry seasons, respectively. In each of the six lagoons three different stands of E. azurea were selected for collecting biological material (macrophytes and associated fauna) and measurement of limnological variables: depth, transparency, temperature, pH, electric conductivity and concentrations of dissolved oxygen and suspended solids. The sampling of E. azurea was performed with a rectangle of 0,1976 m2, gardening shears was used to remove the plant material, which was washed in a solution of formaldehyde and water to remove associated macroinvertebrates. Between the two periods significant differences (p <0,05) were found for both limnological variables, and for the density of some of the taxa macroinvertebrates. In comparison with each other lagoons in March and August, related limnological variables and density of taxa of macroinvertebrates (levels in large groups), the Tukey test showed more significant differences (p <0,05) in March, although some of taxa of macroinvertebrates associated with E. azurea has not presented significant difference between the lagoons in any period sampled. According to principal components analysis, pH and dissolved oxygen are the variables that best explain the ordering of lagoons during the study periods. With respect to the associated fauna, in both periods the class Insecta was the most abundant (especially the family Chironomidae), followed by phylum Crustacea and the class Clitellata. However, comparing the richness of taxa in the months of sampling, it appears that higher values were recorded in August period... (Complete abstract click electronic access below) / Mestre

No description available.

No description available.

No description available.

No description available.

Concentrations of heavy metals (Cu, Cd, Cr, Zn, Mn, Fe and Pb) in the water columns, aquatic plants and sediments of fourteen lakes of varied levels of pollution were measured. Correlation analysis was carried out between heavy metal concentrations in aquatic plants and heavy metal concentrations in water and sediment. The aquatic plants which accumulated heavy metals in their tissues in proportion to that in water and sediments were identified. The aquatic plants studied were: 8/yxa auberti Rich, Cabomba caroliniana Gray, Ceratophyllum demersum L, Ceratopteris thalictroides (L.) Bron, Chara globularis, Eichhornia crassipes Solmn, Hydrilla verticillata Royle, Ipomoea aquatica Forsk, Limnophila aromatica (Lam.) Merr., Ludwigia adscendens (L) Hara, Nelumbo nucifera Gaertn, Nymphaea stallata Linn, Nymphoides indica (L.) Kuntze, Typha angustata Bony & Chaub and Utricularia aurea Lour. Metal uptake by aquatic plants varied between different species and within the same species depending on lake water contamination levels. The level of metal uptake to a great extent was a function of the environment water metal concentration. Results showed that Utricularia accumulated Mn, Zn, Cr, Cd and Pb in direct proportion to the overlying waters (r2 = 0.69, 0.63, 0.69, 0.65 and 0.39 respectively). Hydrilla accumulated Cu, Mn, Zn, Fe, Cr, Cd and Pb in direct proportion to the overlying waters (r2 = 0.65, 0.66, 0.44, 0.72, 0.38, 0.63, and 0.73 respectively). Blyxa leaves accumulated Zn, Fe, Cr, Cd and Pb in direct proportion to the overlying waters (r2 = 0.74, 0.74, 0.72, 0.60 and 0.82 respectively). Echhornia leaf accumulated only Cr in direct proportion to the overlying waters r2 = 0.81. Nymphaea leaf and Chara did not accumulate any metal in direct proportion to the overlying waters. Roots of Blyxa auberti, Ceratopteris thalictroides, and Eichhornia crassipes contained higher concentrations of heavy metals than their leaves. Roots of Blyxa accumulated Cr, Cd and Pb in direct proportion to the overlying waters (r2 = 0.91, 0.65 and 0.69 respectively). Echhornia root accumulated Cd in direct proportion to the overlying waters with r2 = 0.90. Nymphaea stem showed no significant correlations between the metal concentrations in the waters and in the plant. Utricularia accumulated Zn, Fe, Cr, Cd and Pb in direct proportion to the metals in the underlying sediment extracted by cold hydrochloric acid (r2 = 0.84, 0.51, 0.47, 0.68 and 0.80 respectively). Hydrilla accumulated Cu, Zn, Cr, Cd and Pb in direct proportion to the underlying sediment (r2 = 0.34, 0.37, 0.91, 0.49 and 0.96 respectively). Blyxa accumulated Zn, Fe, Cr, Cd and Pb in direct proportion to the underlying sediments (r2 = 0.99, 0.61, 0.82, 0.75 and 0.64 respectively) . Echhornia leaf showed significant correlation between the Cu (r2 = 0.83) and Cr (i2 = 0.88) concentration in underlying sediment and the plant. Nymphaea leaf showed a significant correlation between the Zn (r2 = 0.83) concentration in the plant and the underlying sediments. Roots of Blyxa showed significant correlation between concentrations of Cu, Cr and Pb in sediment extracted by hydrochloric acid and plant (r2 = 0.9, 0.7 and 0.9 respectively). Roots of Echhornia had no significant correlation with the sediment metal concentrations (hydrochloric acid extractable). Two techniques (cold hydrochloric acid extractable and nitric acid extractable) to extract metals from sediment were compared. Based on correlations of metal concentrations in plant tissue and metal extracted from the sediment, it was concluded that the cold hydrochloric acid extractable metal technique is more suitable for determining bioavailable sediment metal concentration in environmental studies. Laboratory studies investigations on the bioaccumulation of Zn and Cu in Hydrilla confirmed that Hydrilla is a good bioindicator of Cu as it accumulated 20360 ug/g dry weight of Cu in 72 hours. Hydrilla showed higher bioaccumulation factor with low concentration of Cu in the solution, in the laboratory studies. Hydrilla was determined to be the best indicator species as it reflected the heavy metal concentration in the environment which was supported by the laboratory studies.