黑河中游沙枣树干液流的动态变化及其与林木个体生长的关系

利用热脉冲树干液流仪, 在生长季节对黑河中游防风固沙树种沙枣树干液流速率进行了连续观测, 结果表明: 沙枣树干液流速率没有明显的昼夜变化规律, 树干液流日平均值在(1.41±0.52)~(2.00±0.66)g·cm^-2·h^-1之间; 树干液流速率8月份最高, 7月份次之, 6月与9月份基本一致。不同的单株在相同月份平均树干液流速率存在差异。树干液流与树木的胸径、胸径的平方与树高之积呈复合指数函数关系, 与边材面积呈线性关系, 与叶面积指数呈现三次幂函数关系。

Sap Flow of Elaeagnus angustifolia and its Relation with Growth Regime in Middle Reaches of Heihe River Basin

The sap flow velocity of Elaeagnus angustifolia was continuously measured during growing season by using heat pulse meter. Results showed that the diurnal sap flow velocity change of Elaeagnus angustifolia hasn't obvious regularity between day and night and the daily average sap flow velocity was between(1.41±0.52)g·cm^-2·h^-1 and(2.00±0.66)g·cm^-2·h^-1; the maximum of average sap flow velocity occurred in August, the second was in July, and the third was in June and in September(it was basically consistent in June and September). As for different individuals, the average sap flow velocity wasn't uniformity in the same month. The average cumulative sap flow showed a strong compound exponential correlation with breast-height diameter(DBH) and product of(DBH)²H, and a linear correlation with sapwood area, and a third power correlation with leaf area index(LAI), respectively.