摘要
云南松生长的环境 ,蕴藏着生长所需要的能量 ,也包含低温、干旱、病虫害等破坏性因素 ,是持续涨落波动的“能量流”。“苗木群体”对不稳定“能量流”的适应 ,表现为通过优胜劣汰而演变为初始林分。能够进入初始林分的“苗木群体” ,可由“平均苗龄” 1～ 10年刻划的“苗木株数递减率”来描述。各种密度的“苗木群体”都通过优胜劣汰的过程进入初始林分 ,它是一种整体性的演变过程。用随机调查的 192个“苗木群体”样本进行导算 ,揭示出 1个“苗木度”为 0 3～ 2 0 ,随“平均苗龄”增长而走向初始林分的演变模型。“平均苗龄” 10年时的株数变动为 2 490 0～ 3 6 2 0株 /hm2 ,也就是初始林分形成 (株数—蓄积量 )结构的时刻 ,从此林分演变过程由“内部时间 (T = D)”刻划的“株数递减率 /蓄积量递增率”来描述。具有时间因素的初始林分 ,是“耗散结构”的起点。
Being “Energy flow”of continuously fluctuating, the environment of Pinus yunnanensis contained not only energy for tree growing, but also destructive factors such as low temperature, drought, disease and insect etc. Plant populations’ adaptation to unstable “Energy flow”was to succession as primary stands by surviving the fittest and discarding unfits. The succession of plant populations to primary stands may described by “decrease rate of tree number”divided by 1～10 years old of the “average tree age”. All plant populations at various densities became primary stands through process of surviving the fittest, of which was the succession process of integrated. After 192 random samples of plant populations were conducted, a succession model of plant populations, whose density is 0 3～2 0, becoming primary stands with the increase of “average tree age”was revealed. The tree number of “average tree age” being 10 years old varied from 24 900 to 3 620 tree/hm 2, and that was the time when the primary stands form their structure. Since then the succession process would be described by “decrease rate of tree number/increase of volume”divided by “internal time (T=)”.The primary stands containing time factors was the start of “dissipative structure”.
出处
《云南林业科技》
2000年第4期10-14,共5页
Yunnan Forestry Science and Technology
关键词
云南松
苗木群体
初始林分
耗散结构
能量流
Pinus yunnanensis,plant population,primary stand,internal time,decrease of tree numb`
