2015年7-9月,对浙江省嵊州市长乐镇小昆村古香榧树进行每株调查,探索产量与胸径、树高、平均冠幅3个树体因子之间存在的趋势性、规律性关系.采用可变参数建模方法,构建了古香榧树青果产量模型.经模型检验,决定系数R2为0.6413,估计精度EA为97.32%,总相对误差TRE为0.0191%,平均相对误差MRE为0.425%.该产量模型能够估测给定胸径、树高和冠幅的古香榧树的平均水平的青果产量,可用于古香榧树经营水平评价、采果经营权林木资源资产批量评估等.%Investigations were implemented on each ancient Torreya grandis cv. Merrillii trees from July to September, 2015, at Xiaokun village, Changle town, Shengzhou, Zhejiang province. The nut yield model was developed by adopting the variable parameter modeling method. By model validation,the coefficient of determination (R2 ) was 0.6413, the estimation accuracy (EA) was 97.32%, the total relative error (TRE) was 0.0191%, the mean relative error (MRE) was 0.425%. The yield model can estimate the output of a given DBH, tree height and crown diameter under average management level. The estimated results can estimate individual management level and forest resources assets of the nut value.
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