【摘要】 以小黑杨为研究材料,研究不同栽植密度(1 000、500、250株/hm2)对林木幼龄材、成熟材生长量的影响。结果表明:不同栽植密度的林木幼龄期为12~13 a,栽植密度对林木幼龄材、成熟材年轮数影响均不显著;栽植密度对林木幼龄材、成熟材宽度及面积的影响极显著,随着栽植密度的减小,幼龄材宽度及面积明显增大,而对于成熟材,500株/hm2的林木生长量较大;不同栽植密度林木幼龄材面积比例达74%~83%,栽植密度最小的林分幼龄材比例最大;幼龄材生长速率要比成熟材大10倍左右,不同栽植密度间幼龄材、成熟材生长速率差异明显。相比而言,栽植密度对小黑杨幼龄材的影响较大。更多还原

【Abstract】 The effects of different planting densities(1 000,500,250 stem/hm2)on growth increment of juvenile and mature wood were studied in Populus×xiaohei.The result indicated that the juvenile period was about 12～13 years and there are no differences in juvenile wood growth rings at different planting densities.The effects of planting densities on widths and basal area of juvenile and mature wood were highly significant.An obvious tendency of increasing juvenile wood width and basal area with decreasing planting densities was seen.The highest mature wood growth increment was found at the planting density of 500 stem/hm2. The percentage of juvenile wood area ranged from 74% to 83% depending on different planting densities.The highest juvenile wood proportion being at the lowest planting density.The growth rate of juvenile wood was about 10 times higher than that of mature wood.There were remarkable differences in the growth rate of both juvenile and mature wood at different planting densities.It′s concluded that planting densities showed various degrees of impact on the growth of juvenile and mature wood,and juvenile wood was more susceptible to planting density.更多还原