间伐强度对杉木－火力楠混交林生长影响的研究初报

对杉木-火力楠混交林进行4种间伐强度试验表明,间伐6年后各林分的杉木、火力楠胸径净生长量比对照分别增加70-139、11-25%,树高增加46-90、7-10%,村积生长增加54-140、10-43%,林分蓄积量增加49-75m³·ha^-1,平均冠高增加2-6、8-13%,第1活枝高下降0.5-3、35-48%.冠幅杉木下降1-2%、火力楠增加1-8%.可以认为,以间伐强度为30和40%2种方式较好,间伐后林分定型株数约保留在1600-2200株·ha^-1之间为宜。

Effect of thinning intensity on the growth or Cunninghumis lanceolata and Michelia maclurei mixed forests

6 years experiment on four thinning intensities of Cunninghamia lanceolata and Micheliameclurri mixed forest shows that in comparing with control, net growth of DBH for C.lanceofata and M.maclurei is respectively by 70-139% and 11-25%,height by 46-90 and 710%, volume by 54-140 and 10-43%, mean crown height by 26 and 8-13%, growing stock of the stand by 49-75m³.ha-1.The height of first living branch isdecreased by 0.5-3 and 35-48%,but crown width by 1-2% for C.lanceofata,and by 1-8% for M.maclurri.Therefore,it is considered that the thinning intensities of 30% and 40% are better than others,and the remainning trees are 1600-2200plant·ha^-1