天宝岩珍稀濒危植物长苞铁杉的生长规律

采用4种数学模型拟合天宝岩长苞铁杉胸径、树高、材积生长过程,并分析其生长规律。结果表明,天宝岩长苞铁杉胸径生长旺盛期在3-36 a;树高在前7 a生长较快,以后逐年下降;材积生长逐年增加,数量成熟期在139-140 a。通过与永泰、连城长苞铁杉生长过程的对比,天宝岩长苞铁杉在第3年就有胸径生长,树高在70 a时达19.27 m。

Growth law of endangered rare plant Tsuga longibracteata in Tianbaoyan

Four mathematical models were used to fit the growth of diameter at breast height(DBH),tree height and volume of Tsuga longibracteata in Tianbaoyan Natural Reserves,and its growth law was analyzed.The results showed that the peak growth period of breast-height diameter of T.longibracteata in Tianbaoyan Natural Reserves was 3-36 years;the tree height increased relatively fast before the age of 7,and decreased with the year after the age of 7;the volume growth increased year by year with the maturity stage between 139 and 140.In contrast with the growth process of T.longibracteata in Yongtai County and Liancheng County,the DBH growth of T.longibracteata in Tianbaoyan Natural Reserves was in the third year,and its height was 19.27 m in the 70th year.