基于目标树中心样圆法的华北落叶松天然林抚育间伐生长效应研究

Effect of Thinning Intensity on Growth of Larix principis-rupprechtii by Using Survey Method of Circular Sample of Target Tree

为探究抚育间伐对华北落叶松天然林生长效应的影响,利用目标树中心样圆法,对关帝林区1998年之前进行过不同抚育间伐强度处理的华北落叶松天然林进行实地调查,发现随着抚育间伐强度的增强,华北落叶松单木材积和生物量增加,但不同间伐强度无显著差异。抚育间伐对林分总的材积和生物量有明显影响,重度间伐会造成林分材积和生物量的显著减少。中重度抚育间伐会显著促进华北落叶松单木胸径的增长。采取中度间伐可以促进林分总生物量的增加,而为了大径材的生产可以采用重度抚育间伐措施。

In order to understand the effect of thinning on the growth of Larix principis- rupprechtii naturalforest, we investigated the Larix principis-rupprechtii natural forest which was thinned in different intensitiesbefore 1998 in Guandi mountain by using survey method of circular sample of target tree. The result showedthat with the thinning intensity increased, single tree＇s volume and biomass were increased too, but the resultswere not significantly different from each other. Three different thinning intensities had significantly effect on Larix principis- rupprechtii stand＇s total volume and biomass, the stand＇s volume and biomass weresignificantly depleted by heavy thinning treatment. The growth of larch tree＇s DBH was significantly promotedby moderate and heavy thinning treatments. Taking moderate thinning treatments could increase the total standbiomass, heavy thinning measures could be used actively in large diameter timber production.