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从冠形、侧枝和叶片在树冠中的空间分布等方面对天然更新木荷(Schima superbaGardn.et Champ.)幼苗的树冠结构进行了研究,认为木荷幼苗的树冠对光照条件的变化有显著的可塑性响应。随着光照水平的提高,幼苗树冠由阔、松散型向相对紧密、窄冠型发展,表明木荷幼苗对不同光照环境有较强的适应能力。木荷幼苗在强光环境下产生短枝,在适度荫庇条件下侧枝和主枝同时向上方和侧方伸长生长;在强度遮阴条件下,侧枝发生强烈的伸长生长并发生强烈的分枝行为,同时在不同自然环境条件下幼苗的叶片密度由全光、林隙到林冠下逐渐提高。随着光照水平的减弱,1级侧枝密度逐渐降低,分枝(2级侧枝和3级侧枝)强度却逐渐增大,且侧枝在树冠上的分布有向上集中的趋势。
The canopy structure of Schima superbaGardn.et Champ. Seedlings was studied from the aspects of the crown, lateral branches and the spatial distribution of leaves in the canopy. The results showed that the crown of Schima superbaGardn.et Champ. Plasticity response. With the improvement of light level, seedling crown from wide and loose to the relatively close, narrow crown development, indicating Schima superba seedlings in different light environments have strong adaptability. Schima superba seedlings produce short shoots in bright light environment, and lateral shoots and main shoots grow upwardly and laterally under the condition of moderate shade protection. Under the condition of intensity shading, the strong and prolonged growth of the side branches occurs with strong points At the same time, the leaf density of seedlings under different natural conditions gradually increased from all-light and gap to canopy. With the decrease of light level, the density of the first grade branches gradually decreased, the intensity of the branches (the second and the third branches) gradually increased, and the distribution of the branches on the canopy tended to concentrate upward.