山茱萸人工林蒸腾速率混沌及分形特征  

Chaotic and fractal characteristics of transpiration rate of Cornus officinalis plantation

作　　者：张劲松[1] 孟平[1] 高峻[1] 王鹤松[1] 

机构地区：[1]中国林业科学研究院林业研究所国家林业局林木培育重点实验室,北京100091

出　　处：《生态学杂志》2008年第4期661-666,共6页Chinese Journal of Ecology

基　　金：国家自然科学基金项目(30471371);国家"十一五"科技支撑资助项目(006BAD03A11)

摘　　要：利用热扩散液流法测算了华北山地山茱萸人工林的蒸腾,采用相空间重建法,分析了林木蒸腾速率混沌及分形特征。结果表明:林木蒸腾过程是一种混沌运动,具有分形性质;2005年与2006年主要生长季节期间,延滞时间(τ)为10min时,蒸腾速率(Tr)的分形维数(D)分别是1.054和1.041,二阶Renyi熵(K2)分别为0.0082和0.0086,此时嵌入维数(m)均为10,平均预报时长(T)分别约为122.0和116.3min,描述其变化过程所需独立变量至少为2个,上限值为10个;尽管2005年和2006年主要生长季节Tr在数量上或外表变化规律上存在差异性(如:总蒸腾量相差25.6%),但在相同τ条件下,D和K2在2005年与2006年差异均极小,故本质特征或内在规律性不存在差异。Based on the data measured with thermal dissipation probes in 2005 and 2006, and by the method of phase space reconstruction, the chaotic and fractal characteristics of transpiration rate （ Tr） of Cornus officinalis plantation in the mountainous region of North China were analyzed. The results showed that the plantation transpiration was a chaotic motion, and characterized by fractal pattern. At the lag time （τ） of 10min, the fractal dimension （D）, Renyi entropy （K2）, embedding dimension （m）, and average predictability time scale （T） in main gTowth seasons were 1. 054, 0. 0082, 10, and 122.0 min in 2005 and 1. 041, 0. 0086, 10, and 116. 3 min in 2006, and the least and most limit amount of the independent variables for describing or simulating the dynamics of the plantation transpiration were 2 and 10, respectively. Despite the significant difference in the amount or external appearance of Tr between the two years, less difference in D and K2 was observed at same r, suggesting that there were no differences in the natural characteristics or internal patterns of Tr in different years.

关 键 词：山茱萸人工林 蒸腾 混沌 分形 

分 类 号：S716[农业科学—林学]