水土保持学报2011，Vol.25Issue(3)：193-197,5.
辽东栎不同方位边材液流季节动态及其对蒸腾耗水测算的影响
Seasonal Dynamics and Azimuthal Variations of Sap Flow in Quercus liaotungensis and Their Effects on Transpiration Estimates
摘要
Abstract
The Granier-type thermal dissipation probes (TDP) were applied to a naturally-growing Quercus liaotungensis tree in the semiarid loess plateau region to measure the long-term dynamics and azimuthal variations of sap flow on xylem trunk. Air temperature, relative air humidity, and solar radiation were monitored at the same time. In this paper, the correlations among sap flux densities at four different azimuthal directions, effects of different data source on the estimates of whole-tree sap flow and transpiration, and the relationships among sap flow and environmental factors had been investigated. The results showed that sap flux densities at four aspects (north, south, east and west) on the trunk were significantly different, but were highly linearly correlated. Daily whole-tree transpiration throughout the growing season (May to October) could be well fitted to the corresponding daily total solar radiation and average daytime air vapor pressure deficit using exponential saturation functions. The differences relative to tree transpiration estimates based on sap flux densities for four aspects were typically 30 ％ and 18％ in accordance with the sap flux densities for one and two measurement aspects, respectively. The results suggested that azimuthal variations of sap flux density could be a large source of errors in tree transpiration estimates.关键词
方位差异/黄土高原/辽东栎/树干液流/热扩散探针/蒸腾耗水Key words
azimuthal variation/ loess plateau/ Quercus liaotungensis/ sap flow/ thermal dissipation probe (TDP)/ transpiration分类
农业科技引用本文复制引用
张建国,闫美杰,时伟宇,杜盛..辽东栎不同方位边材液流季节动态及其对蒸腾耗水测算的影响[J].水土保持学报,2011,25(3):193-197,5.基金项目
中国科学院知识创新工程重要方向项目(kzcx2-yw-BR-02) （kzcx2-yw-BR-02）
