哀牢山中山湿性常绿阔叶林林窗更新研究

对云南哀牢山中山湿性常绿阔叶林林窗更新状况的调查结果表明，林内优势树种在林窗阶段不占优势，其在林窗内的重要值显著低于成熟林分；林窗内外的乔木幼苗在组成上存在较大差异，林窗内的幼苗多样性(H=2．73，D=0．89)高于林冠下(H=2．25，D=0．82)，二者的Jaccard相似系数只有0．6．许多树种的幼苗只出现在林窗内；林窗内的乔木幼苗密度(38636株·hm²)远远高于林冠下(17323株·hm²)．林窗内和林冠下的乔木幼苗(H≤50cm)均以高度为11～20cm幼苗的在数量上占优势，但林窗内高度超过20cm的幼苗比例明显高于林冠下；林窗大小对乔木幼苗更新有重要影响，不同树种的幼苗密度高峰出现在不同大小级别的林窗内．

Regeneration in gaps of the middle-mountain moist evergreen broad-leaved forest of Ailao Mountains

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.