Fig. 2. Loss of C and humic substances from the forest floor as a function of time. Each point represents one of five replicate plots. Data for the first year is connected by a dashed line. Data for Years 1 to 13 are represented by a solid exponential regression line and the regression statistics refer to data from 1 to 13 yr. As a statistical rationale for excluding the first year decomposition from the regression, we found that neither the 95% nor the 99% confidence intervals for the data at x = 0 yr included the intercept predicted from the regressions in Fig. 2.