几种模型下砂生槐叶绿素荧光-快速光响应曲线(RLCs)拟合的比较

以西藏砂生槐(Sophora moorcroftiana)为试材,采用直角双曲线模型、非直角双曲线模型、单指数方程、双指数方程和双曲线修正模型对2个种源砂生槐叶绿素荧光-快速光响应曲线进行拟合,研究了5种模型对砂生槐叶绿素荧光-快速光响应曲线的适用性,以期为筛选最优模型和深入研究砂生槐的生理生态提供参考。结果表明:直角双曲线模型、非直角双曲线模型和单指数方程无法拟合砂生槐PSⅡ动力学下调时(光抑制)的曲线,不能拟合砂生槐的饱和光强(PAR_sat),最大电子传递效率(J_max)比实测值高。双指数方程和双曲线修正模型可以拟合砂生槐的主要荧光参数,但双指数方程拟合的最大电子传递效率(J_max)低于实测值,饱和光强(PAR_sat)高于实测值;双曲线修正模型拟合出的主要荧光参数,其拟合值与实测值相关性最强(R^2=0.998、R^2=0.994)。利用均方根误差(RMSE)、平均相对误差绝对值(MAE)和赤池信息量准则(AIC)评价5种光合模型,发现双曲线修正模型(MRH)拟合的光合参数可信性最高,显著优于其它4种光合模型。在5种光合模型中用双曲线修正模型拟合砂生槐叶绿素荧光-快速光曲线是最佳模型。

Comparison of the Fitting Several Models With the Chlorophyll Fluorescence Rapid Light Curves (RLC_S) Method of Sophora moorcroftiana

The chlorophyll fluorescence-rapid light curve of two provenances of Sophora moorcrofiana was fittd by rectangular hyperbolic model,non-rectangular hyperbolic model,single exponential equation,double exponential equation and modified rectangular hyperbolic model with Sophora moorcrofiana of Tibet as a research material,and the applicability of five models to the chlorophyll fluorescence-rapid light curve of Sophora moorcroftiana was studied.In order to provide a reference for screening the optimal model and further studied the physiology and ecology of Sophora moorcrofiana.The results showed that rectangular hyperbolic model,non-rectangular hyperbolic model and single exponential equation could not fit the curves(photoinhibition) with dynamic down-regulation of PSⅡ and could not directly calculate the saturation irradiance(PARsat) of Sophora moorcrofiana,and the maximum electron transport rate(Jmax) was higher than the measured values.The main fluorescence parameters fitted by the double exponential equation and modified rectangular hyperbolic model of Sophora moorcroftiana,but the maximum electron transfer rate(Jmax) fitted by the double exponential equation was lower than the measured value,and the saturation irradiance(PARsat) was higher than the measured value.The main fluorescence parameters fitted by modified rectangular hyperbolic model had the strongest correlation with the measured values(R2=0.998,R2=0.994).Root Mean Square Error(RMSE),Mean Absolute Error(MAE) and Akaichi Information Criterion(AIC) were used to evaluate the five photosynthetic models,it was found that the fluorescence parameters fitted by modified rectangular hyperbola model had the highest credibility and it had a significant superior to the other four photosynthetic models.In the five photosynthetic models,modified rectangular hyperbolic model was the best model to fit the chlorophyll fluorescence-rapid light curve of Sophora moorcrofiana.