抚育间伐对光皮桦次生林生长的影响

对分布于贵州省织金县茶店乡的7年生光皮桦次生林进行抚育间伐试验。结果表明：抚育间伐对林分胸径、树高和单株材积生长具有不同程度的影响：强度间伐的影响均达到显著程度,中度间伐的影响对胸径、树高生长未达到显著水平,对单株材积生长达到显著程度。试验林分的蓄积量总体上呈逐渐上升趋势,强度间伐林分的蓄积量最高,中度间伐林分次之,对照林分最低。间伐之后10年,强度间伐林分的平均胸径、树高、单株材积和蓄积量,比对照林分分别高31.3%、28.2%、116.5%和44.7%,中度间伐林分比对照林分分别高10.0%、9.3%、30.8%和23.3%。在试验地区中等立地条件下,对林龄为7年、密度达7 630株/hm2以上的光皮桦次生林,进行适宜强度的抚育间伐是十分必要的。如要将其培育成为建筑、家具、坑木等用材林,按株数计算的间伐强度以不低于50%为宜。

Effect of Thinning on Growth of Secondary Betula luminifera Forest

Thinning experiment of secondary Betula luminifera forest located on Chadian Township of Zhijin County in Guizhou Province were carried out herein.The result showed that the thinning had different effects on the breast-height diameter,height and individual volume growth of the stands.All effects of heavy thinning on them achieved significant level.Effects of moderate thinning on breast-height diameter and height growth were not significant,but effect on individual volume growth gained significant result.Gro...