应用生态学报2011，Vol.22Issue(12)：3109-3116,8.
不同环境因子对兴安落叶松树干液流的时滞效应复杂性及其综合影响
Complexity and its integrative effects of the time lags of environment factors affecting Larix gmelinii stem sap flow
摘要
Abstract
Based on the one-year ( 2005) observations with a frequency of half hour on the stem sap flow of Larix gmelinii plantation trees planted in 1969 and the related environmental factors air humidity ( RH), air temperature ( Tair) , photosynthetic components active radiation ( PAR), soil temperature ( Tsiol) , and soil moisture (TDR), principal analysis ( PCA) and correction analysis were made on the time lag effect of the stem flow in different seasons (26 days of each season) and in a year via dislocation analysis, with the complexity and its integrative effects of the time lags of environment factors affecting the stem sap flow approached. The results showed that in different seasons and for different environmental factors, the time lag effect varied obviously. In general, the time lag of PAR was 0. 5-1 hour ahead of sap flow, that of Tair and RH was 0-2 hours ahead of or behind the sap flow, and the time lags of Tsoil and TDR were much longer or sometimes undetect-able. Because of the complexity of the time lags, no evident improvements were observed in the linear correlations (R2, slope, and intercept) when the time lags based on short-term (20 days) data were used to correct the time lags based on whole year data. However, obvious improvements were found in the standardized and non-standardized correlation coefficients in stepwise multiple regressions , I. E. , the time lag corrections could improve the effects of RH, but decreased the effects of PAR, Tair, and Tsiol, PCA could be used to simplify the complexity. The first and the second principal components could stand for over 75% information of all the environmental factors in different seasons and in whole year. The time lags of both the first and the second principal components were 1-1.5 hours in advance of the sap flow, except in winter (no time lag effect).关键词
兴安落叶松/时滞效应/主成分分析/逐步回归分析/环境因子Key words
Larix gmelinii/ time lag/ principal components analysis/ stepwise regression analysis/environmental factor分类
农业科技引用本文复制引用
王慧梅,孙伟,祖元刚,王文杰..不同环境因子对兴安落叶松树干液流的时滞效应复杂性及其综合影响[J].应用生态学报,2011,22(12):3109-3116,8.基金项目
国家自然科学基金项目(31100457,31170575)、中国博士后基金项目(20080430126,201003406)和中央高校基本科研业务费专项资金项目(DL09CA17,DL12DA03)资助. （31100457,31170575）
