杉木幼苗不同光质光响应曲线的模型拟合及光合特性比较

Comparison of light response curve fitting model and photosynthetic characteristics about Chinese fir seedlings under different light qualities

以2年生无性系幼苗为试验材料,利用直角双曲线模型、非直角双曲线模型和直角双曲线修正模型分别对白光、红光和蓝光3种光质条件下杉木光合光响应曲线进行拟合,并分析3种光质条件下杉木的光合特性。结果表明,非直角双曲线模型适用于白光和红光的拟合,直角双曲线修正模型则适用于蓝光的拟合,而直角双曲线模型对3种光质的拟合效果均较差。弱光环境中(I≤200μmol·m-2·s-1),红光下杉木具有较强的光合能力,其光合速率、气孔导度和水分利用效率均较高;强光环境中(I>200μmol·m-2·s-1),蓝光下杉木具有更强的光合能力,白光下的光合速率则介于红光和蓝光之间。

The light response curve fitting models and photosynthetic characteristics of 2-year old Chinese fir （ Cunninghamia lanceo- lata） seedlings under three light conditions （ white, red and blue） were compared using rectangular hyperbolic, non-rectangular hy- perbolic, and rectangular hyperbolic correction models, respectively. The results showed that the non-rectangular hyperbolic model was suitable for the fitting of white and red lights, the rectangular hyperbolic correction model was suitable for the fitting of blue light, and the rectangular hyperbolic model was not suitable for fitting of any light. Under low intensity of red light （I ~〈 200 μmol· m-2· s-1）, C.lanceolata seedlings had relatively higher photosynthetic rate, higher stomatal conductance, and higher water use efficiency. Under high intensity of blue light （≥200 μmol· m-2· s-1 ）, C. lanceolata seedlings had relative higher photosyn- thetic capacity. Under white light, the photosynthetic rate of C.lanceolata seedlings was between those under the red and the blue lights.