DOC in bulk precipitation
The average BP DOC concentration was 5.17 (± 4.25) mg.L-1, presenting considerable variation between the events. Highlights were the highest concentrations in EV3 and EV7, respectively in winter and spring (figure 5). Apart from these two occurrences, the DOC concentration was always below the level of 04 mg.L-1, with the lowest concentration occurring at the end of winter (EV4).
Rainfall intensity was the only variable to present a significant linear model in an inversely proportional relationship to BP DOC concentrations (table 2). Regarding the previous rainfall variables, the time-interval of better adjustment was the previous 15-days, but the significance value did not corroborate the model (P > 0.05).
When analyzed by multiple regression the two variables of best individual adjustments (RfI and AcR 15-day), there increased the coefficient of determination, but the model was non-significant. When analyzing all variables combined (excluding the accumulated 10 and 30 days), there was a considerable increase in the determination coefficient, but remaining a non-significant model.