毛竹发笋与幼竹生长规律研究

Studies on the Rule of Bamboo Shooting and Young Bamboo Growth of Phyllostachys edulis

以崇阳毛竹为研究对象,在毛竹生长较好的林分内进行标准地设置与调查,对笋体出土与毛竹幼竹生长规律进行了研究。结果表明,崇阳县毛竹在正常情况下的出笋期为3月下旬至4月下旬,持续35 d左右。在出笋期间,各天出笋率和退笋率均服从正态分布。从笋体出土到地径生长停止为止,地径生长期约为25 d,表现出"S"生长节律。从笋体出土到毛竹竹高生长停止,毛竹高生长期约45 d,比地径生长期长约20 d,毛竹幼竹高生长过程出现昼夜节律,其竹高生长过程符合Logistic回归模型。利用Fisher最优分割法可将幼竹生长过程划分为4个阶段:笋体出土期(第1~13 d)、幼竹较快速生长期(第14~25 d)、幼竹快速生长期(第26~35 d)及幼竹形成期(第36~45 d)。毛竹各生长因子之间存在相关性,如地径与胸径为线性相关,地径与竹高以及胸径与竹高均为幂函数相关。依据毛竹发笋与幼竹生长规律,提出了维持毛竹林分可持续经营相应的生产技术。

Phyllostachys edulis in Chongyang had been taken as a research object. Plots bad been set in growth better stands, and a research had been carried out into characteristics both bamboo shooting and young bamboo growth of Phillostachys edulis. Results showed under normal circumstances, Bamboo shoot period was from late March to late April, lasting about 35 d in Chongyang. Both the shooting rate and the degenerated shoot rate presented as a normal distribution during whole shooting period. The diameter at ground growth stage was about 25 d, showing ＂S＂ growth rhythm. Young bamboo height growth showed day-night rhythm, the height growth process with 45 d was a Logistic regression model, and the height growth process was 20 d longer than that of the diameter at ground. Young bamboo growth process could be divided into 4 stages by means of Fisher time order cluster analysis., the bamboo shooting stage（1-13 d）, the bamboo accelerating growth stage（14 - 25 d）, the fast growth stage（26 - 35 d）and the young bamboo stage（36 - 45 d）. There were regressions between P. edulis growth factors, i. e diameter at ground to diameter at breast height was a linear, both diameter at breast height to height and diameter at ground to height a power. Based on characteristics of bamboo shooting and young bamboo growth, many suggestions corresponding production technology had been put forward in order to maintain a Moso bamboo stand sustainable management.