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对16个美洲黑杨(Populus deltoides Marsh.)×欧美杨(P.×euramericana)无性系单株进行了树干解析,计算树高、胸径和材积的平均生长量、连年生长量与胸高形数;得到对树高、胸径和材积历年生长的拟合Logistic生长曲线。结果表明:(1)无性系748、893和6585干形最好,其胸高形数都在0·6以上;(2)树高、胸径和材积的生长用Logistic方程拟合精度高,R2分别为0·9999、0·9980和0·9956;(3)树高、胸径和材积速生点分别为:第3、4、9年,速生期分别为1~6、1~7、5~13a,最大生长速率分别为:2·75m/a、3·59cm/a和0·081m3/a。
The trunk analysis of 16 Populus deltoides Marsh × P. euramericana clones was performed to calculate the average growth, annual growth and chest height of tree height, DBH and volume. The logistic growth curve fitted to the tree height, DBH and volume growth over the years was obtained. The results showed that: (1) The clones of 748, 893 and 6585 were the best in dry form with the number of breast height above 0.6. (2) The growth of tree height, DBH and volume were highly fitted by Logistic equation, R2 Which was 0.999, 0.9980 and 0.9595 respectively. (3) The fast-growing points of tree height, DBH and volume were respectively 3, 4 and 9 years old, and the fast-growing period was 1 ~ 6,1 ~ 7,5 ~ 13a , The maximum growth rates were: 2.75m / a, 3.59cm / a and 0.081m3 / a respectively.