杉木第2代和第3代良种幼龄期林分生长对比分析

The Comparative Analysis on the Juvenile Trees from the Second- and Third-generation Improved Cunninghamia lanceolata

为比较不同代数杉木良种的使用效果,2012年在福建省来舟林业试验场营建了杉木第3代良种和第2代良种对比试验林,2012-2014年调查分析了试验林1a、2a、3a生时的树高和3a生时的胸径指标。结果表明:使用杉木良种效果显著,幼林期生长量高,林分整齐。3a生时总体平均树高为3.69m,变异系数为18.20%;平均胸径为5.05cm,变异系数为24.75%。第3代良种造林效果明显优于第2代良种,3a生时树高、胸径和单株立木材积分别比第2代良种大3.59%、10.65%和14.58%,第3代良种的良种性在幼龄期就已得到充分体现。

To compare the growth effects of different generation improved Cunninghamia lanceolata, the test plantation of the second- and third-generation improved C. lanceolata was set up for comparative study in Fujian Provmcial Laizhou National Forest Farm. From 2012 to 2014, the tree height at the age of one year old, two years old and three years old, and the DBH at the age of three years old plantation were analyzed. The results showed there were remark- able effects on the growth effects of the second- and third-generation improved C. lanceolata. The growth increment of the juvenile trees was high and the plantation was uniform. The average tree height was 3.69 m at the age of three years old, and the variation coefficient was 18.02%; the average DBH was 5.05 cm, and the variation coefficient was 24.75%. It was evident that the afforestation effect of third-generation improved C. lanceolata was better than that of the second generation. A the age of three years old, the tree height, DBH and the volume per individual of the third generation were 3.59%, 10.65% and 14.58% higher than that of the second generation, respectively. The improved characteristics of the third generation were expressed at the juvenile plantation.