摘要
【目的】通过研究胡杨的光响应曲线及光合参数特征,阐明胡杨在不同灌水量下的光合-光响应机制,筛选不同灌水量下不同树龄胡杨的最优拟合模型。【方法】通过Li-6400光合仪测定不同灌水量[无灌水量(CK)、20 kg/株·次(T_(1))、40 kg/株·次(T_(2))、60 kg/株·次(T_(3))]下3 a、5 a和7 a胡杨的光响应过程,获取光合特征参数,采用4种光响应模型进行拟合分析。【结果】不同模型对胡杨光响应过程及光合参数模拟存在差异,表观量子效率(AQY)拟合采用指数模型(AQY=0.039);直角双曲线修正模型对T_(1)(20 kg)、T_(3)(60 kg)灌水下3 a、7 a胡杨和T_(1)、T_(2)灌水下5 a胡杨Pn max拟合效果最好[Pn max分别为22.83、22.03、22.01、28.78μmol/(m^(2)·s)],直角双曲线和双曲线修正模型对暗呼吸率(Rd)拟合效果相当。5 a和7 a胡杨光补偿点(LCP)、光饱和点(LSP)采用双曲线修正模型,3 a胡杨LCP、LSP采用指数模型拟合效果最佳。【结论】综合平均绝对误差(MAE)、均方根误差(MSE)和决定系数(R2)评价胡杨在不同灌水量的光合响应模拟效果,双曲线修正模型适用于各种灌水条件,拟合优度最高。
【Objective】By studying the light response curve and parameter characteristics of Populus euphratica,the photosynthesis-light response mechanism of P.euphratica under different irrigation levels was clarified in order to screen out the optimal fitting model suitable for different tree ages under different irrigation levels.【Method】The photoresponse process of P.euphratica at 3 years,5 years and 7 years under different irrigation levels was measured by Li-6400 photosynthesis instrument,the photosynthetic characteristic parameters were obtained,and four photoresponse models were used to fit and analyze them.【Result】Different models have differences in simulation of the light response process and photosynthetic parameters of P.euphratica.The exponential model was used to fit the apparent quantum efficiency(AQY=0.039);the right-angle hyperbolic correction model has the best fitting effect on the Pn max of P.euphratica under T_(1)(20 kg)and T_(3)(60 kg)irrigation for 3 years and 7 years and T_(1) and T_(2)(40 kg)under irrigation for 5 years[Pn max were 22.83,22.03,22.01,28.78μmol/(m^(2)·s)respectively].The right-angle hyperbolic and hyperbolic correction models have comparable fitting effects on the dark respiration rate(Rd).The light compensation point(LCP)and light saturation point(LSP)of P.euphratica in 5 years and 7 years adopt the hyperbolic correction model,and the LCP and LSP of P.euphratica in 3 years adopt the best fitting effect of the exponential model.【Conclusion】The coefficients of determination(R2)of the four photosynthesis models were all well fitted,and the combined mean absolute error(MAE)and root mean square error(MSE)suggested that the hyperbolic modified model was more suitable for different irrigation conditions and had the highest goodness of fit.
作者
陈跃萍
武胜利
史智欣
岳永江
何宇翔
CHEN Yueping;WU Shengli;SHI Zhixin;YUE Yongjiang;HE Yuxiang(College of Geographical Science and Tourism,Xinjiang Normal University,Xinjiang Key Laboratory of Lake Envi-ronment and Resources in Arid Areas,Urumqi 830054,China)
出处
《甘肃农业大学学报》
CAS
CSCD
2023年第1期146-155,共10页
Journal of Gansu Agricultural University
基金
新疆维吾尔自治区科技支撑专项塔里木河中下游胡杨生态修复研究与示范(HY-2.3)。
关键词
胡杨
灌水量
光响应
光合参数
光合模型
Populus euphratica
irrigation amount
light response
photosynthetic parameters
photosynthetic model
