一年生云南松苗期生长动态规律研究

基于1a生云南松苗高和地径的定株、定期观测数据,采用Logistic方程对其生长过程进行拟合,根据其中参数分析生长动态规律。结果表明:(1)地径生长符合"S"型曲线,呈现"慢-快-慢"节律;苗高生长符合双"S"型曲线,呈现"慢-快-慢-快-慢"节律。(2)根据生长量变化规律,苗高生长过程可分为出苗期、速生期Ⅰ、过渡期、速生期Ⅱ和生长后期;地径生长过程可分为生长前期、速生期和生长后期。(3)苗高两个速生期为23～34d和89～150d,两个速生点时间为第28天和第120天;地径速生期为141～211d,速生点时间为第176天。(4)苗高、地径的累积生长量均在速生期最大,分别占理论上限值的58.37%和57.85%。(5)苗高、地径的生长表现出异速现象,150d之前苗木主要进行高生长、150d之后则以地径生长为主。

Dynamic Growth Rhythm of One-year Old Seedling of Pinus yunnanensis

Based on the data of height and basal diameters growth of one-year old seedlings of Pinus yunnanensis,the dynamic growth rhythm was analyzed by the growth parameters which were simulated from the Logistic Model.The results showed that:(1) The basal diameters growth of one-year seedlings of P.yunnanensis exhibited a "S-shaped" curve as "slow-fast-slow" while the of seedling height were presented as a "double S-shaped" curve as "slow-fast-slow-fast-slow".(2) The growth of seedling height could be described as the stage of sprouting,fast-growing Ⅰ,transition,fast-growing Ⅱ and late growing,while the basal diameters growth could be classified as pre-growing,fast-growing and late-growing stage.(3) Two durations of the fast-growing stage in respective of seeding height occurred during 23~34 d and 89~150 d respectively,the fast growing points occurred on the day 28 and day 120,respectively.For the basal diameters,the duration of fast-growing stage was 141~211 d and the fast growing point occurred on the day 176.(4) The largest accumulations of seedling height and basal diameters occurred during the fast growing stage,accounting for 58.37% and 57.85% of theoretic maximum number,respectively.(5) The allometry phenomenon were observed on the growth of seedling height and basal diameters,it was the seedling height that took the lead during the seedling stage before 150 d,and the basal diameters after 150 d.