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研究了广东亚热带42种木本植物幼苗的生长及其与物种的生态特性、生活型、种子大小的相互关系。较强光下(H,66.8 μmol m-2s-1)乔木幼苗的茎高和茎生物量显著高于灌木幼苗的相应值,但在较低光下(L, 33.7 μmol m-2s-1)两者无显著差异。而阳性植物、耐阴植物和中间型植物之间,茎高和茎生物量无显著差别。乔木幼苗的叶面积和叶生物量比灌木幼苗大,但灌木幼苗的叶片数较乔木幼苗多。大种子种和小种子种幼苗之间,阳性植物、耐阴植物和中间型植物幼苗之间的叶片数和叶面积一般无显著差异。阳性植物幼苗比耐阴植物幼苗侧根数多。乔木幼苗的根生物量和根/茎比显著高于灌木幼苗。在较高光下, 阳性植物幼苗的根/茎比较耐阴植物幼苗高,但在较低光下无明显差异。45 d幼苗的根生物量与种子重量呈显著的正相关,而90 d幼苗无明显的相关。乔木幼苗个体生物量显著高于灌木幼苗。幼苗相对生长率和叶面积比的大小呈现如下顺序:阳性植物> 中间型植物> 耐阴植物,但只有阳性植物和耐阴植物之间有显著差异。阳性植物、中间型植物和耐阴植物幼苗之间的单位叶率无显著差异。
The growth of seedlings of 42 species of woody plants in subtropical area of Guangdong and their relationship with the ecological characteristics, life form and seed size of the species were studied. The stem height and stem biomass of tree seedlings under high light (66.8 μmol m-2s-1) were significantly higher than those of shrub seedlings, but under low light (L, 33.7 μmol m-2s-1) No significant difference between the two. The positive plants, shade-tolerant plants and intermediate plants, stem height and stem biomass no significant difference. The leaf area and leaf biomass of tree seedlings were larger than shrub seedlings, but shrub seedlings had more leaves than tree seedlings. There were generally no significant differences in the number of leaves and leaf area between seedlings of large seeds and small seeds, between positive plants, shade-tolerant plants and intermediate plantlets. Positive plants more seedlings than shade-tolerant plantlets more roots. The root biomass and root / shoot ratio of tree seedlings were significantly higher than that of shrub seedlings. Under higher light, the seedlings of positive plants had higher root / shoot resistance than shade-tolerant plantlets, but no significant difference at lower light. There was a significant positive correlation between the seedling weight and the root biomass of seedlings on the 45th day, but no obvious correlation on the seedlings on the 90th day. The individual biomass of tree seedlings was significantly higher than that of shrub seedlings. The relative growth rate and leaf area ratio of seedlings showed the following order: positive plants> intermediate plants> shade-tolerant plants, but there was significant difference between positive plants and shade-tolerant plants. There was no significant difference in unit leaf rate between positive plants, intermediate plants and shade-tolerant seedlings.