间伐对柳杉人工林生长的影响

Effect of Thinning on Increment of Crypotomeria fortunei Plantation

2015年对浙江省缙云县柳杉(Crypotomeria fortunei)人工纯林样地调查不同间伐措施对其平均胸径、平均树高、蓄积量及胸径生长的影响。对照样地为1983年造林,至今未间伐;1977年造林1988年间伐1次作为1次间伐样地,1988年和1998年各间伐1次作为2次间伐样地。结果表明:间伐对柳杉林分的平均胸径和蓄积量的增长有极显著的影响,林分的平均胸径、平均树高以及单株材积均是间伐2次样地>间伐1次样地>对照样地;间伐对径级分布和树高分布影响明显,密度越大,径级株数高峰期越早,且树高分布越均匀;间伐样地的胸径生长速率均高于对照样地,间伐1次样地的生长量在后期开始减弱,而间伐2次样地的胸径生长速率始终高于间伐1次样地。

In 2015, investigations were implemented on mean DBH, mean tree height, volume and DBH of Crypotomeria fortunei plantations in Jinyun, Zhejiang province. The control was the stand planted in 1983 without any thinning so far, and the other 2 sample plots with treatment of thinning once and twice. The results showed that thinning had significant effect on mean DBH and volume growth. Mean DBH, mean tree height and individual tree volume was ordered by thinning twice 〉 thinning once 〉control, as well as diameter increment.