Demography of Larix gmclini seedling population in natural old-growth forests of north Daxinganling Mts EXPERIMENTAL STUDIES ON FATE OF LARIX GMELINI SEEDS IN THE SOIL IN OLD-GROWTH LARCH STANDS Dynamics of aboveground biomass of sub-alpine old-growth forest in the upper Minjiang River(UMR) Natural Regeneration of Larix gmelini Seedlings and Micro-habitat in old-growth Larix gmelini Forests