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比较盆栽陆生榕树和两栖型榕树的形态差异、叶片叶绿素含量、叶绿素荧光特性和气体交换的日变化 .两栖型榕树具有较发达的气生根和水生不定根 ,叶片比陆生榕树宽 ,并有向中生性发展的倾向 ,陆生榕树的叶绿素含量比两栖型榕树高 .净光合速率略高于水培两栖型榕树 ,但明显高于土培两栖型榕树 ,蒸腾速率以水培两栖型榕树最高 ,陆生榕树次之 ,土培两栖型榕树最低 ,线性回归分析表明 ,三者的叶片气孔导度与净光合速率变化均呈正相关 ,气孔导度的变化是以上气体交换特征变化的主导控制因子 .内在水分利用效率 (净光合速率与气孔导度的比值 ,IntrinsicWUE)比常用的水分利用效率 (净光合速率与蒸腾速率的比值 ,WUE)更适宜描述榕树的光合和水分特性 ,其中 ,土培两栖型榕树的内在水分利用效率最高 .
The morphological differences of chlorophyll content, chlorophyll fluorescence and diurnal variation of gas exchange between terrestrial banyan and amphibian banyan were compared.The amphibian banyan has more developed aerial and aquatic adventitious roots with wider leaves than terrestrial banyan, In the tendency of sexual development, terrestrial banyan tree had higher chlorophyll content than amphibian banyan tree.The net photosynthetic rate was slightly higher than that of amphibian banyan, but it was significantly higher than that of amphibian banyan.The transpiration rate was the highest in transplanting banyan, The lowest was banyan tree and the second was birch. The linear regression analysis showed that there was a positive correlation between the leaf stomatal conductance and the net photosynthetic rate. The stomatal conductance was the dominant controlling factor of the above gas exchange characteristics. IntrinsicWUE was more suitable than the commonly used water use efficiency (net photosynthetic rate and transpiration rate ratio, WUE) to describe the photosynthetic and water characteristics of banyan trees, and the intrinsic water use efficiency (net photosynthetic rate versus stomatal conductance) Banyan trees have the highest intrinsic water use efficiency.