Q(10) of heterotrophic activity during aerobic decomposition of Utricularia breviscapa and its effect on carbon cycling in a tropical lagoon

Autor(es)

Cunha-Santino, M. B. ^[1] ; Bianchini Junior, I ^[2]

Afiliação do(s) autor(es)

^[1] Univ Fed Sao Carlos, Dept Hidrobiol, BR-13565905 Sao Carlos, SP - Brazil

^[2] Univ Fed Sao Carlos, Programa PosGrad Ecol & Recursos Nat, BR-13565905 Sao Carlos, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Brazilian Journal of Biology; v. 70, n. 2, p. 317-324, MAY 2010.
• Citações Web of Science: 1

Resumo

In this study the Q(10) coefficients of heterotrophic activities were measured during aerobic decomposition of Utricularia breviscapa Wright ex Griseb from Oleo lagoon (21 degrees 36' S and 49 degrees 47' W). Lutz Antonio, SP. The bioassays were set up with fragments of U. breviscapa and incubated with lagoon water at distinct temperatures (15.3, 20.8. 25.7 and 30.3 degrees C). Periodically for 95 days, the concentrations of dissolved oxygen were determined in the bioassays. The results of the temporal variation of dissolved oxygen were fitted to a first-order kinetic model. The stoichiometric relations were calculated on the basis of these fittings. In general. the results allowed us to conclude: i) the oxygen/carbon stoichiometric relations (O/C) varied in function of temperature and time. The temporal variations of the O/C observed in the decomposition of U. breviscapa, suggest that. in the initial phases of the process. low organic carbon concentrations were enough to generate great demands of oxygen. ii) the oxygen consumption coefficients (k(d)) presented low variation in function of increasing temperature, iii) the increment of the temperature induced a higher consumption of Oxygen (COmax) and iv) the simulations indicate that during summer, temperature activates the metabolism of decomposing microbiota. (AU)

• Processo FAPESP: 00/09297-6 - O efeito da temperatura e o papel das enzimas na decomposição de Salvinia auriculata e Utricularia gibba da Lagoa do Óleo (Luiz Antônio, SP)
• Beneficiário: Irineu Bianchini Júnior
• Modalidade de apoio: Auxílio à Pesquisa - Regular