Abstract: Based on the previous researches on fallen trees in forest, the storage dynamics of fallen trees in Korean pine broad-leaved forest in Changbai Mountain and its relation to the dynamic patterns of their decomposition were studied. The study revealed that the decomposition of the fallen trees was from the surface to the inside, except the heart-rot woods. Under the same ecological conditions, the decomposition rate was decided by their species, diameter and position. The storage dynamics of fallen trees in Korean pine broad-leaved forest included two aspects, i.e., the storage now available and the annual input of fallen trees. The dry existing fallen trees reduced rapidly during the first 100 years storage, and the decomposition of the basswood was faster than that of the Korean pine, the former being decomposed 91% and the latter being72%. The storage dynamics of the fallen trees was similar with their annual input decomposition, but the former increased considerably greater, because some fallen trees were not decomposed completely. After 100 years, the existing storage and decomposition tended to stabilized at 16～17 t·hm^-2 until the climax community ended.

Key words: Decomposition of fallen trees, Korean pine, Basswood, Korean pine broad-leaved forest, rhizosphere soil, fungal community, poplar plantation, high-throughput sequencing, root orders