The effect of temperature on the glucose cycling and oxygen uptake rates in the Infernão Lagoon water, state of São Paulo, Brazil

Abstract

Experiments were carried out to verify the temperature effect on the mineralization process of an artificial source of organic matter. Incubations were prepared with water samples from the Infernão Lagoon (21^º35’S and 47^º51’W), enriched with glucose (20 mg.L^-1). Bottles were kept with and without aeration for 8 days. Glucose and oxygen concentrations were registered; the results were adjusted to first order kinetic models. The Q₁₀ of each process was estimated by the reaction coefficients obtained. Temperature had greater influence on the process of oxygen consumption (Q₁₀=6.23) than on glucose decay. For glucose consumption, the anaerobic process was more sensitive (Q₁₀=3.30) to temperature than the aerobic one (Q₁₀=1.12). Results suggest that in the Infernão Lagoon the anaerobic cycling processes are favored in warmer seasons whereas, in colder months, the aerobic process may prevail.