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尖峰岭热带天然林,树种繁杂,林木生长存在较大的差异。根据65株不同树种的解析木,按树高和胸径的年生长量划分为三种类型,即年平均生长量大于0.5(m或 cm)者为速生型,0.2—0.5者为中生型,小于0.2为慢生型,其中83.1％属于中生型,对各类型分别调制了生长过程的回归估测模型。材积生长量在三个类型中仍继续增长,数量成熟龄尚难确定。从缩短经营周期出发,可考虑采用工艺成熟龄作为择伐的回归年。据回归估测,速生型40年,中生型140年,慢生型180年,胸径可达32cm,树高23—24m,平均单株材积达0.9m~3以上,符合锯材原木标准,可考虑作为择伐回归年的依据。
Jianfengling tropical natural forests, tree species complicated, there is a big difference in tree growth. According to the analysis of 65 different tree species, tree height and DBH annual growth were divided into three types, namely, the average annual growth of more than 0.5 (m or cm) for the fast-growing type, 0.2-0.5 for the Mesozoic type, Less than 0.2 is slow-type, of which 83.1% belongs to the Mesozoic type, for each type of growth were modulated regression estimation model. Volume growth in the three types continue to grow, the number of mature age is difficult to determine. Proceeding from the shortening of the business cycle, we may consider the use of process maturity as a selective regression of the year. According to regression estimation, 40 years of fast-growing type, 140 years of mesophyll, 180 years of slow-growing type, DBH up to 32cm, tree height 23-24m, the average single plant volume of 0.9m ~ 3 or more, in line with timber standard lumber, May be considered as the basis for the return of seventy years of selection.