Regeneration in gaps of the middle-mountain moist evergreen broad-leaved forest of Ailao Mountains
哀牢山中山湿性常绿阔叶林林窗更新研究

On the basis of investigation on gaps in the middle-mountain moist evergreen broad-leaved forest of Ailao Mountains Natural Reserve, Yunnan Province, tree seedlings (H<50 cm) composition were compared in the gaps and the non-gap stand. The results showed that the dominant tree species of the forest were not preponderated over others in the gaps. The composition of tree seedlings in the gaps differed from those in the non-gap stand. The species diversity of tree seedlings in the gaps(H= 2.73, D = 0.89)were higher than those in the non-gap stand (H = 2.25, D=0.82), and the Jaccard correlative coefficient were only 0.6. The density of tree seedlings in the gaps (38 636 N.hm-2) was much higher than that in the non-gap stand (17 323 N.hm-2), of which many species were only found in the gaps. The dominant height of the tree seedling in the gaps and the non-gap stand were also 11-20 cm, but the percentage of the tree seedlings higher than 20cm in the gaps was significantly higher than that in the non-gap stand. The gap sizes had important impact on the tree seedling germination, and different species of tree seedling dominated in different size classes of gap.