ENVIRONMENTAL CONSEQUENCES in rocky mountain coniferous ...

LITTER
Figure 3.-- SoiZ organic matter type and percent occurrence in soit cores.
The natural balance between fire and decay, as a regulatory process for
organic matter accumulations on these sites, is documented by the relative proportion
af decay in woody residue (fig. 4), and by the incidence of charcoal in the soil
samples (figs. 5 and 6). As we might expect, decay was highest in warm moist
environments, lowest in cold or dry sites. Conversely, charcoal was most abundant
in cold or dry systems and least abundant on warm-moist sites.
This pattern indicates that productive ecosystems regulate organic matter
accumulation by means of those processes having the fewest external constraints.
Thus, the cold Teton site is temperature-decay 1 imited and fire dominated, while
the Priest River site is moisture-decay dominated and fire limited. Under inter-
mediate conditions, the balance between processes is more complex. For example,
since the decay process breaks down organic matter to C02 and water, presumably
moisture may be less limiting to the production of soil-wood than temperature.
In general, high residue accumulations appear to be characteristic of cool ecosystems.
More research is needed to adequately define this area of residue ecology.