摘要
将4个纬度上（大兴安岭塔河、大兴安岭松岭、黑河孙吴、伊春带岭）8年生的兴安落叶松（Larix gmelinii Rupr．）幼树移栽到其分布区的南缘构成4个实验处理，以探索树木水分关系的时空变化格局及其影响因子。采用基于热平衡方法的包裹式茎流计和环境因子自动测定系统同步测定移栽自4个纬度的兴安落叶松的树干液流及其相应的环境因子。研究结果表明：兴安落叶松的树干液流密度基本上呈现单峰曲线日变化格局，而日最大液流出现的时间随生长季节和实验处理不同而略有变化。移栽自4个纬度的兴安落叶松的平均单位边材面积液流通量在展叶前、中和后期分别为26．24—54．45g·cm^-2·d^-1、114．33—355．39g·cm^-2·d^-1和58．32—304．03g·cm^-2·d^-1。展叶期间落叶松的日耗水量与距地面10cm处树干直径呈显著的正相关关系；单位边材面积液流通量与针叶长度呈显著的正相关关系。影响树干液流密度的环境因子随生长阶段和实验处理而变化，主要包括太阳辐射、水蒸气压亏缺、相对湿度、气温和风速，其中太阳辐射通常是影响树干液流密度的关键因子。
To examine spatial-temporal dynamic patterns of tree water relations and their controlling factors, we transplanted 8-year-old Dahurian larch （ Larix gmelinii Rupr. ） trees to the southern boundary of its distribution area from four locations, i. e. , Tahe （52°31′N, 124°39′E）, Songling （50°43′N, 124°25′E）, Sunwu （49°13′N, 127°12′E） and Dailing （47°05′ N, 128°54′E） , comprising four experimental treatments. The heat balance method was applied to measure stem sap flow for the larch trees, while an automatic weather station with Campbell Scientific dataloggers was used to measure associated environmental factors. The sap flow density basically showed a bell-shaped diurnal pattern, but the daily maximum value of sap flow density occurred at different times depending on growing seasons and experimental treatments. The mean sap flow flux per unit sapwood area of the four treatments varied 26.24 -54.45 g·cm^-2·d^-1, 114.33-355.39 g·cm^-2·d^-1 and 58. 32-304.03 g·cm^-2·d^-1 during prior to foliar expanding, foliar expanding, and posterior to foliar expanding periods, respectively. The amount of daily water assumption was significantly positively correlated to stem diameter at 10 cm above ground surface; while sap flow flux per unit sapwood area was significantly correlated to the length of needles during the foliar expanding period. The environmental factors influencing sap flow density, including solar radiation, vapor pressure deficit, relative humidity, air temperature and wind speed, changed with the growing periods and treatments, among which the solar radiation was usually the key factor.
出处
《生态学报》
CAS
CSCD
北大核心
2008年第1期136-144,共9页
Acta Ecologica Sinica
基金
国家自然科学基金资助项目(No.30625010,30470304)~~
关键词
树干液流
兴安落叶松
热平衡法
stem sap flow
Larix gmelinii Rupr.
heat balance method
