摘要:Differential site index models were constructed using both the algebraic difference approach (ADA) and thegeneralized algebraic difference approach (GADA) in this study to evaluate the site quality of forest landwithout the site index table. Data related to China fir (Cunninghamia lanceolata (Lamb.) Hook.) were selectedto fit the differential site index models and then the optimal model was chosen. The optimal model wasdetermined using an accuracy test and residual analysis, and then the dynamic update technique of theoptimal model was studied by MATLAB and .NET. The results showed that Richards’ differential site indexmodel (SI = 19.171 × (H t /19.171) ln(1-exp(-0.067×20))/ln(1-exp(-0.067 At)) ) had the best prediction performance. The ADAand GADA could be used to evaluate site quality without the site index table and the differential site indexmodel could provide prompt dynamic updates.