Size distribution and carbon-to-nitrogen ratios of size-fractionated organic matter in the forest floor of coniferous and broadleaved stands

The C/N ratios of the forest floor under coniferous stands usually converge to higher values than those under broadleaved stands. Because litter decom position progresses with physical disintegration and chemical deterioration , if disintegration is delayed so that larger organic matter having a high C/N ratio accumulates, the C/N ratio of the organic layer is hypothesized t o be high. To test this hypothesis, a comparison of the size distribution o f forest floor organic matter was made between a coniferous stand group and a broadleaved stand group. The results showed that no clear difference exi sts in the size distribution between the two groups. In the H layers the co niferous group showed significantly higher C/N ratios than the broadleaved group even in the finer size of the organic matter.