Abstract:litter decomposition rates of dominant tree species were determined using litterbag burying method in three altitudinal belts of the Broad-leaved Korean Pine forest, Spruce-fir forest and Ermans Birch forest in Changbai Mountain nature reserve during a period of three years from 2001 to 2003. Spatial and temporal dynamics and impact of litter quality were examined with a simulation model for understanding the trophic strategy of main species and ecosystem circulation of material and promoty ecosystem based forest management. The results indicated that annual mass loss increased over time, following a non-linear pattern. The leaf decomposition of all major tree species accelerated after 683 day(1.75year).By the end of study period(699 day), the remaining dry weight of buried leaves from 1ess to bigger was 24.56 for Asian White Birch(Betula platyphylla), 24.81% for Amur Linden(Tilia amurensis), 38.48% for Korean Pine(Pinus koraiensis), 41.15% for Yezo Spruce Cheng et L.K.Fu(Picea jezoensis var. microsperam), 41.53% for Ermans birch(Betula ermanii) and 42.62% for Khingan Fir(Abies nephrolepis). The decomposition rates of twigs were lower than those of leaves, and the remaining dry weight followed to order of AL(44.98%)<KF(64.62%)<KP(72.07%)<YS Cheng et L.K.Fu(73.51%)<AWB (77.37%)<E B (80.35%).At the same altitude, the decomposition rates of broad-leaved litterfall were higher than those of conifer’s. Among different altitude, decomposition decreased with the increase elevation.
The modelly analysis suggested that 95% decomposition of leaves takes about 4.5 to 8.0 years for major tree species in the three altitudinal belts. Annual leaf decomposition rates (k) 0.686 for AL, 0.624 for AWB,0.441 for KP, 0.406 for YSCheng et L.K.Fu, 0.397 for KF and 0.385 for EB. The 95% decomposition for twig ranged from 7.8 to 29.3 years,with large differences among different species. The annual decomposition rate (k) for twigs from high to low was 0.391 for AL, 0.204 for KF, 0.176 for KP, 0.157 for YS Cheng et L.K.Fu, 0.148 for AWB and 0.102 for EB.