思茅松林分演变过程周期性的研究

Study on Periodicity of Evolution of Pinus kesiya var. langbianensis Stand

优良木（Ⅰ、Ⅱ、Ⅲ级木）的成长和分化，被压木（Ⅳ、Ⅴ级木）的衰退和死亡，是思茅松林分演变过程中相互联系的两方面。林分平均直径的变化与“内部时间（Ｔ＝Ｄ）”有关系。由“内部时间（Ｔ＝Ｄ）”刻划的“立木度／蓄积度”序列，与由“内部时间（Ｔ＝Ｄ）”刻划的“株数递减率／蓄积量递增率”序列的相互关联关系，反映出林分结构状态的演变。在８、１６、３２这几个临界时刻，“立木度／蓄积度”的数值都趋近１０，这是思茅松林分演变的３个周期，对应着周期性的转移概率序列。用在判断林分生长、预测林分演变过程、确定林分间伐强度等方面都有使用价值。

The growth and differentiation of the superior trees (classes Ⅰ,Ⅱ,Ⅲ) and the decline and death of the suppressed trees (classes Ⅳ,Ⅴ) were correlative 2 aspects in the evolution of Pinus kesiya var. langbianensis stand. The change of stand average diameter was related with the “inside time(T=D)”, the relationship between the array “stocking percent/volume percent” depicted by “inside time(T=D)” and the array “tree number lapse rate/volume increase rate” depicted by “inside time(T=D)” represented the evolution of stand structure. In the critical moment of 8, 16 and 32, the ratio of stocking percent to volume percent was tending towards 1 0, these were 3 periodicities of evolution of Pinus kesiya var. langbianensis stand, and were corresponding with periodic transfer probability array. The research results also indicated that transfer probability was valuable to estimate growth quality of stand, predict evolution procedure of stand and determine intermediate cutting intensity of stand.