The objective of this research was to determine the best light response model for Phyllostachys pubescens. Based on measurements of leaf photosynthesis response curves from January 2009 to January 2010,the light response curves for photosynthesis of Ph. pubescens were fitted to four different models: a non-rectangular hyperbolic model, a rectangular hyperbolic model, a quadratic function, and an exponential equation. Results of R2 obtained from the four methods were in the order: non-rectangular hyperbolic model and rectangular hyperbola model (R2＞0.95)＞exponential equation＞quadratic function. Using the non-rectangular hyperbolic and rectangular hyperbolic models for maximum net photosynthetic rates (Pmax) and dark respiration rate (Rd), the calculated results were much greater than the measured data; whereas with the index model, Pmax was accurate and Rd was slightly lower than measured values. Also, a quadratic function was used to fit the light saturation point (PLS) and Rd. Thus, an exponential equation could be used to calculate PLS and Pmax with a linear fitting of YAQ, light compensation point(PLC), and Rd using values following 100 μmol·m-2·s-1.%为更好地开展毛竹Phyllostachys pubescens固碳研究,筛选适合毛竹的光响应模型的基础性研究显得十分必要.以3年生毛竹叶片2009年1月-2010年1月光合响应曲线测定资料为基础,利用非直角双曲线模型、直角双曲线模型、二次函数和指教方程4种方法,对毛竹光响应曲线进行拟合.结果表明:非直角双曲线模型与直角双曲线模型拟合的相关度最高,均大于0.95,指数方程次之,二次函数最差;但非直角双曲线模型与直角双曲线模型所求出的最大净光合速率(Pmax)和暗呼吸速率(Rd)较实测值高,指数模型的拟合结果准确,但对暗呼吸速率(Rd)的拟合结果比实测值低;二次函数所拟合的光饱和点(PLS)与暗呼吸速率(Rd)均不正确.建议计算PLS和Pmax时使用指数方程,计算表观光量子效率(YAQ),光补偿点(PLC)和Rd时使用50-100μmol·m-2·s-1以下数值进行直线拟合.
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