木麻黄林下青皮苗光合作用特性对光照度的响应

为了比较木麻黄林下不同光照处理的青皮苗叶片的光合作用特性,采用Li-6400便携式全自动光合测定仪对不同光照处理的青皮苗叶片光合作用参数及相关环境因子进行了日变化测定.结果表明,随着遮阴程度的增加,青皮苗叶片光合作用参数净光合速率、气孔导度、蒸腾速率逐渐降低；不加遮阳网的2特光照处理的净光合速率、气孔导度、蒸腾速率、水分利用效率比加遮阳网处理的大,而胞间CO2浓度低于加遮阳网处理的.3种光照处理下的青皮苗叶片净光合速率、气孔导度、蒸腾速率与环境中光合有效辐射的日变化趋势相符,并且影响净光合速率的主要环境因子相似.建议在木麻黄林阴环境下无需进行青皮苗的人工遮阳处理,可选择光照适度的地方种植.

Photosynthetic Characteristics of Vatica mangachapoi Seedlings Respond to the Light Intensity in Casuarina equisetifolia Forest

In order to compare the photosynthesis characteristics of Vatica mangachapoi Blanco seedlings in Casuarina equisetifolia forest,the daily variation of the photosynthetic parameters and related environmental factors were measured using Li-6400 portable automatic photosynthesis.The results showed that with the shading degree increase,V.mangachapoi seedling leaf photosynthetic parameters net photosynthetic rate,stomatal conductance,transpiration rate decreased gradually.The net photosynthetic rate,stomatal conductance,transpiration rate,water use efficiency of the 2 light treatments without shading was greater than that of the treatment with shading;and the intercellular CO2 concentration was lower.The variation trend of the leaf net photosynthetic rate,stomatal conductance,transpiration rate of the three light treatments was similar to that of photosynthetic active radiation.It was not necessary for planting V.mangachapoi seedlings in C.equisetifolia forest environment with artificial shading treatment.