Tesis
Fotorreatividade e biodisponibilidade da matéria orgânica dissolvida produzida por Microcystis aeruginosa
Fecha
2010-03-30Registro en:
BITTAR, Thais Beraldo. Fotorreatividade e biodisponibilidade da matéria orgânica dissolvida produzida por Microcystis aeruginosa. 2010. 149 f. Tese (Doutorado em Ciências Biológicas) - Universidade Federal de São Carlos, São Carlos, 2010.
Autor
Bittar, Thais Beraldo
Institución
Resumen
Photochemically and biologically mediated reactions are key processes on the transformation of dissolved organic matter (DOM) in natural waters. The aims of this study were to evaluate these isolated and coupled processes over the DOM produced by the Cyanobacteria Microcystis aeruginosa, which contributes with great amounts of biomass in the Barra Bonita Reservoir. Our results showed that photodegradation occurred, but also showed that there were cyanobacterial photoresistant molecules and photoproducts that were identified in the Reservoir s DOM. Pre exposure of the DOM released by M. aeruginosa caused decrease in bioavailability of this type of DOM due to competition, i.e., removal of the biolabile portion of the DOM by irradiation. The bioavailability of intracellular DOM was not significantly altered by pre exposure to UV radiation. Detailed chemical characterization showed that competition between photo and biodegradation and photoproduction of biolabile compounds, equilibrated negative and positive effects of irradiation on the bioavailability of the intracellular DOM.