不同间伐强度对杉木人工林林分生长的影响

Effects of intermediate cutting intensities on growth of planted Cunninghamia lanceolata forests

为探明不同间伐强度对杉木林生长的影响,以浏阳地区4种间伐强度(20%,30%,40%和50%)下的杉木人工林为对象,样地内每木标尺,连续3年测量林木胸径和树高,对比分析不同间伐强度下平均胸径和树高变化。结果表明:不同间伐强度对杉木人工林胸径连年生长量的影响差异显著,当间伐强度为40%时,可促进胸径连续性增长,并合理控制树体高度;不同间伐强度之间树高的差异均不显著。从经济效益分析,间伐强度40%的整体增长趋势较明显,具有连续性,适合当地采用。

In order to verify the effect of different thinning intensities on the growth of Cunninghamia lanceolata plantations,four thinning intensities（ 20%,30%,40%,50%） in Liuyang district as the object,an investigation was conducted on the DBH and tree height. The results showed that the DBH of 40% thinning intensity was significantly higher than other groups. There was no difference in the tree height of Cunninghamia lanceolata plantations among four thinning intensities and CK plots. For what it was worth,analysis suggested that adopting the thinning intensity of 40% has obrious growth and suitable to the local development.