薄壳山核桃不同品种光响应过程及模型拟合

Light response in different pecan cultivars and model fitting of the process

为了探讨不同光响应模型对于薄壳山核桃光合作用的适用性,以‘Mahan’、‘Stuart’、和‘Kanza’3个薄壳山核桃品种为研究对象,建立了5种光响应模型(直角双曲线模型、非直角双曲线模型、直角双曲线修正模型、指数模型和指数修正模型),分别对各薄壳山核桃品种的光响应过程进行了拟合。结果表明:1)5种光响应模型对薄壳山核桃的光响应拟合效果突出,决定系数均在0.9以上,其中非直角双曲线模型拟合效果最优,R^2达到了0.99,并且AIC值最低,直角双曲线模型σ及AIC最高,表现最差。2)通过与实测值相比较,直角双曲线修正模型对于光响应特征参数的求解效果最好,求解出的AQY、R_d、LSP和Pn_(max)最准确,非直角双曲线模型求解LCP最佳。3)‘Mahan’在3个品种中光照生态幅最宽,利用光能能力最强;‘Stuart’在各模型中的R^2均达到0.99,运用光响应模型拟合效果最好。

In order to explore the applicability of different light response models to photosynthesis of Carya illinoensis, five light response models (rectangular hyperbolic model, non-rectangular hyperbolic model, modified rectangular model, exponential model and modified exponential model l) were established based on three varieties of C. illinoensis, such as ‘Mahan’,‘Mahan’ and‘Kanza’, and the light response processes were fitted. The results are as follows. 1) All 5 kinds of models fitted well and the determination coefficients of them were above 0.9;Among these models, non-rectangular hyperbolic model had the best fitting effect whose determination coefficient could reach 0.99 and had the lowest AIC;Rectangular hyperbolic model fitted worse than other models since its σ and AIC were the highest. 2) Compared with the measured values, the rectangular hyperbolic correction model had the best solution effect on the light response characteristic parameters, the solved AQY, Rd, LSP and Pnmax were the most accurate, and the non-rectangular hyperbolic model was the best for LCP. 3) Among the three cultivars,‘Mahan’had the widest light ecological range and the strongest ability to utilize light energy;R2 of‘Mahan’reached 0.99 in each model, and the fitting effect of the light response model of ‘Mahan’was the best.