光合有效辐射比率（FPAR）是陆地生态系统碳循环研究的重要参数。根据FPAR的物理意义，本文提出了有效FPAR的概念：即叶绿素吸收的FPAR（FPARchl），利用模拟数据建立了有效FPAR信息模型。探讨了基于叶绿素含量估算有效FPAR的可行性，为进一步采用有效FPAR来估算NPP／GPP提供思路和途径。利用实测数据对有效FPAR模型进行验证表明：（1）叶片吸收的FPAR（FPARleaf）与有效FPAR（FPARchl）之间的差异较大。FPARchl通常不足FPARleaf的50％，两者之间虽存在一定的相关性，而这种相关性是非线性的；（2）叶绿素含量与FPARleaf的相关性较高，而与FPARchl的相关性更高，基于叶绿素含量可以以较高的精度估算FPARleaf和FPARchl经过验证，估算的平均相对误差分别为2．90％和6．6％；（3）应用模拟数据建立的FPARleaf及有效FPAR模型均在叶绿素含量大于20μg／cm。时估算的精度较高，而低于20μg／cm^2时估算的精度较低，本文中叶绿素含量大于20μg／cm^2的60个样本的FPARleaf及FPARchl的估算的平均相对误差，分别为1．79％和5．07％。

The Fraction ofAbsorbed PhotosyntheticallyActiveRadiation(FPAR) has been recognized as one\nof the mi portantvariables in carbon cycle research ofterrestrialecosystem. According to the physicalmeaning of\nFPAR, the conceptofeffectiveFPAR, which isFPAR absorbed by chlorophyllwithin the lea,f is introduced in\nthis article. We developed the effective FPAR remote sensingmodel using smi ulated data, and analyzed the\nfeasibility ofestmi ating effective FPAR based on chlorophyll content, whichwas expected to introduce away to\nestmi ateNPP/GPP using effective FPAR. The results showed: (1) the difference between FPAR absorbed by\nleaf(FPARleaf) and FPAR absorbed by chlorophyll(FPARchl) cannot be neglected. FPARchlis notmore than\n50% ofFPARleafbasically. The correlation betweenFPARchland FPARleafisnonlinear. (2) A strong correlation was found between chlorophyll content and FPARleaf, but the correlation between chlorophyll content and\nFPARchlismuch stronger. So FPARleafand FPARchlcan be accurately estmi ated based on chlorophyll content,\nand the estmi ation average errors are 2·90% and 6·6% respectively. (3) the estmi ation accuracy ofFPARleaf\nand FPARchlmodels is higher when chlorophyll content is not less than 20μg/cm2. For 60 samples that\nchlorophyll content isnot less than 20μg/cm2, the average errors ofestmi ated FPARleafand FPARchlare 1·79%\nand 5·07% respectively.