黔南马尾松人工林生长规律研究

Study on growth rhythm of Pinus massoniana plantation in the south of Guizhou Province

对35 a生的马尾松人工林纯林进行树干解析,结果表明:35 a生以前,胸径、树高和材积的总生长量随林龄的增加而增加;胸径和树高的平均生长量的最大值都出现在15 a左右,其连年生长量的最大值都出现在10 a左右;20 a以后是材积生长的速生期,连年生长量都在0.020 m3以上,连年生长量和平均生长量在35 a前未达到最大值,两曲线未相交,说明该马尾松林分在35 a生仍未达到数量成熟龄;该区域马尾松人工林各测树因子和林龄的拟合模型分别为:胸径:Y=97.342 9×(1-EXP-0.014 6x)1.253 3;树高:Y=20.352 9×(1-EXP-0.089 4x)1.827 0;材积:Y=3.183 4×(1-EXP-0.035 0x)4.115 1;该区域马尾松胸径和树高激烈分化时期均在15 a左右,在此期间应进行间伐;由马尾松材积生长模型,并结合两曲线的走势,可知该林分数量成熟龄在65 a左右,此后可进行主伐。

The stem analyses of Pinus massoniana forest of 35-year-old were conducted. The results show that the total increments of diameter, height and volume increased with forest age increasing before 35-year-old. The maxmium average growth of diameter and height appeared in 15-year-old, and the maxmiun of current annual increment appeared in 10-year-old. Volumn reached the fast growing period after 20-year-old, and current annual increment was over 0. 020 ma. Current annual increment and average increment did not reach the maxmium before 35-yearold, and their＇s curves which were not intersection show that Pinus massoniana before 35-year-old did not reach the quantitative mature age. Pinus massoniana fitting model between forest measurement factors and forest age in this area were： Ydiameter = 97. 342 9 X （ 1 - EXP^-0.0146x）^1.2533, Yheighr = 20. 352 9 × （ 1 - EXP^-0.0894x ）^1.8270, Yvolumn= 3. 183 4× （1-EXP^-0.0350x）^4.1151. Intense split apart period of diameter and height were in 15-year-old, and inter- mediate cuttings was done in this period. Through Pinus massoniana volumn growth model, with the trend of two curves current annual increment and average increment, it was found that the quantitative mature age was 65-yearold, and the principle felling could be clone in this period.