Tree Leaf Biomass, and Rates of Litterfall, Decomposition and Litter Accumulation through Three Stages of a Successional Sere in Northern Utah
The leaf biomass, leaf productivity, litterfall, decomposition and litter accumulation were determined for each stage of a successional sequence that begins with quaking aspen, passes to subalpine fir and ends with engelmann spruce. Leaf biomass was highest in the near climax spruce stands (18.4 mt/ha) and lowest in the pioneer aspen stands (2.6 mt/ha). Leaf productivity was 1.8 mt/ha, 1.3 mt/ha and 1.3 mt/ha in the aspen, fir and spruce stages respectively. Annual litterfall was greatest in the spruce (1.9 mt/ha) and least in the aspen .(.8 mt/ha) though there is evidence that the aspen litterfall was severely underestimated. Leaves were the major component of the total litterfall in all three stages. Decomposition rates were greatly affected by winter snow accumulation. When snow pack approximated the normal most of the annual decomposition occurred during the winter months. Under these conditions aspen litter decomposed more rapidly than the coniferous litter. No significant differences were ever found between fir and spruce litter decomposition. Litter accumulation was highest in the conifers (160 mt/ha and 144 mt/ha in fir and spruce respectively). The high litter accumulation in the fir stands is due to the large amounts of downed stems. Calculated litter accumulations based on leaf fall or leaf productivity and leaf decomposition rates (K) indicate that none of the stages has reached an equilibrium in leaf litter accumulation.
Williams, Steven E. (1977). Tree leaf biomass, and rates of litterfall, decomposition and litter accumulation through three stages of a successional sere in northern Utah. MS.