日本柏在浙江中山地区的生长量检测

Increment of Three Cypress Trees in Middle-high Mountains of Zhejiang Province

通过设置标准地,选择标准木,对日本扁柏、日本花柏和日本香柏等柏木树种生长过程进行研究。结果表明:(1)3个树种胸径在造林后3~4 a基本没有生长,日本扁柏、日本花柏胸径连年生长量曲线与平均生长量曲线相交于造林后8~9 a,日本香柏则是在造林后11~12 a,其连年生长量开始低于平均生长量,造林后8~15 a是胸径生长的旺盛期,应在造林10 a左右进行间伐。(2)树高生长量均在造林10 a内增长迅速,其旺盛生长期为造林后5~10 a,3个树种的连年生长量曲线和平均生长量曲线相交于造林后9~11 a。(3)材积连年生长量与平均生长量在早期生长缓慢,在造林0~20 a生长速度较为一致,而在造林20 a后,日本花柏材积连年生长量明显大于另外2个树种,解析木材积从小到大依次为日本扁柏(0.248 7 m3)、日本香柏(0.253 6 m3)、日本花柏(0.317 2m3)。(4)造林35 a后,3个树种林分均未到达成熟期,应对林分进行抚育管理等措施,达到培育柏木大径材的目的。

We studied the growth process of three cypress trees by stem analysis （ Chamaecyparis obtuse, Thuja standishii and C. pisifera）. For three species, the growth of DBH （diameter at breast height） had nearly no increase in the first 3-4 a after planting. The annual growth curve and the average growth curve of Chamaecyparis obtuse and C. pisifera intersected in for- estation after 8-9 a, and the successive growth started to be lower than the average growth rate 11-12 a after planting T. standishii. DBH of vigorous growth period appeared during 8-15 a after afforestation, and the three cypress tree stands should be thinned after 10 a of afforestation. The growth of height increased rapidly in the first 10 a of afforestation, and its vigorous growth period lasted for 5-10 a, and the current annual increment curve and average growth curve intersected after afforestation 9-11 a. Annual and average volume growth quantity growth turned slow in the 0-20 a afforestation, and after 20 a of afforestation, C. pisifera volume successive growth was significantly greater than the other two species, the volume order of timber is C. obtuse （0.248 7 m3 ）, T. standishii （0.253 6 m3 ） , and C. pisifera （0.317 2 m3 ）. After 35 a afforestation, forest stands of the three species were not maturity demanded forest tending and management measures to cultivate the cypress big diameter timber.