关键词: 高山松, 种群结构, 静态生命表, 生存分析, 时间序列预测

Abstract:

After a comprehensive investigation on Pinus densata populations that distribute in southeast Tibet by transects and quadrats, this paper analyzed the diameter class, height class and crown width class, compiled the static life table, drew survival curve, mortality curve, killing power curve, and four survival function curve (Survival rate, accumulated mortality rate, morality density rate and hazard rate), investigated population quantitative characteristics, and predicted population quantitative dynamics by a time sequence prediction model. The results showed that the individual number of P. densata was slight fluctuant with structure level (the diameter class, height class and crown width class), but the number in the three structures was generally presented as the anti-"J" type, and the population belonged to growing type. The survival number of every diameter class had obvious difference, the mortality rate of age Ⅳ was relatively low (13%), that of age Ⅷ was highest (70%), and the average mortality rate accounted for 42%. The survival curve of P. densata population approached to the B₁ subtype of Deevey-Ⅱ. With the increase of the population age class, the mortality rate had a similar change trend to the killing power, and they all presented double-peak curves. Four survival function curve for P. densata population indicated that the population would have an early reduction, a mid-term stability, and a late recession because of physiological exhaustion. The time sequence model predicted that P. densata population had strong recovery capability, and the amount of population would have a different rising tendency in the upcoming 3, 6 and 9 age classes.

Key words: Pinus densata, population structure, static life table, survival analysis, time sequence prediction