新疆乌拉泊库区主要乔木树种树干液流对比研究

选择新疆乌拉泊库区沙枣、银白杨、大果榆、白榆和火炬等5种乔木树种,于2009年5月份和8月份对树干液流和气象进行同步监测。结果表明:(1)沙枣、银白杨和火炬树干液流表现为单峰曲线;大果榆和白榆树干液流则为双峰曲线;5月份平均液流流速为火炬>银白杨>沙枣>大果榆>白榆;8月份树干液流平均流速为沙枣>白榆>大果榆>火炬=银白杨。(2)5种树种的树干液流流速与气温、太阳辐射强度呈极显著正相关,与空气相对湿度呈极显著负相关;除大果榆树干液流与风速呈显著相关外,其余树种树干液流流速与风速关系不密切。(3)沙枣、大果榆和白榆8月份树干液流流速比5月份高;火炬则表现出相反的变化趋势;银白杨变化不明显;5种树种的日耗水量也表现出类似的变化;各树种5月份日耗水量为大果榆>白榆>火炬>银白杨>沙枣;8月份的日耗水量为大果榆>白榆>沙枣>银白杨>火炬。

Sap flow dynamics of the major tree species and its relationship with meteorologic factors in Wulabo reservior, Xinjiang

This study selected Elaeaguns angustifolia, Populus Alba, Ulmus macrocarpa , U.pumila and Rhus tynhina in water resources protection forest in Wulabo, Xinjiang, and simultaneously measured the sap flow velocity and related environmental factors using thermal dissipation method and automatic measuring system of weather station. The results showed that. (1) Among with the exception of Ulmus macrocarpa and U.pumila whose sap flow velocity exhibited typical double-peak diurnal patterNs, the sap flow velocity of other tree species exhibited wide mono-peak diurnal patterns; The order of average slap flow velocity in May was Rhus tynhin>Populus alba>Elaeaguns angustifolia>Ulmus macrocarpa>U.pumil. The order of average slap flow velocity in August was Elaeaguns angustifolia>Ulmus pumila>U.macrocarpa>Rhus tynhina=Populus alba. (2) The sap flow velocities of the five arbors species were positively correlated with air temperature and solar radiation, and were negatively correlated with relative humidity. With the exception of Ulmus macrocarpa whose sap flow velocity was positively correlated with wind speed, the sap flow velocities of other trees were not correlated with wind speed. (3) The sap flow velocities of Elaeaguns angustifolia, Ulmus macrocarpa and U.pumila in August were higher than those in May. It was opposite to Rhus tynhina; the difference of Ulmus pumila of the sap flow in May and in August was not significant. Meanwhile, the diurnal water consumption also exhibited the similar change. The order of diurnal water consumptions in May was Ulmus macrocarpa>U.pumila>Rhus tynhina>Populus alba>Elaeaguns angustifolia; diurnal water consumptions in August was: Ulmus macrocarpa>U.pumila>Elaeaguns angustifolia>Populus alba>Rhus tynhina.