摘要
采用基于热补偿原理的SF100热脉冲茎秆液流自动监测系统,监测了柠条树干液流的日季变化规律,利用TubeTDR监测柠条根区3m土层深度的含水量变化,利用自动气象站同步监测太阳辐射、最高与最低气温、相对湿度、风速、风向等气象因子,同时输出相应的参考作物蒸发蒸腾量ET0。以上述资料为基础,对柠条树干液流的昼夜变化、日际动态、木质部径向不同位点液流速率、不同天气条件下的液流变化及液流的季节变化规律进行了分析。利用SPSS11.0统计软件,分析了液流量与气象因子的相关关系。结果表明:柠条树干液流昼夜变化显著;木质部径向液流速率随探针插入深度的增加而减小;晴天液流变化幅度较大,雨天液流变化幅度较小;气象因素对柠条树干液流量影响的大小表现为空气水汽压差>太阳辐射>气温>风速。
The SF100 Heat pulse sensors based on the heat compensation theory were applied to study the diurnal and seasonal changes of trunk sap flows for Caragana korshinskii. The soil moisture content at 0 ～ 300 cm layer was measured with a tube-type time domain reflectometry （Tube-TDR）. The solar radiation, the maximum and minimum air temperature, relative humidity, wind speed, wind direction and precipitation etc. were also measured with an automatic weather station where the reference crop evapotranspiration was provided simultaneously. The diumal and seasonal variations of sap fluxes, the flow velocity at different positions in the trunk and the sap fluxes under different weather conditions were analyzed. The correlation between the sap flux and the meteorological factors was also analyzed by SPSS 11.0 statistical software. Results showed that the trunk sap flow varied regularly in the diurnal term and the sap flow velocity decreased with the inserted depth into the sapwood. Magnitude of sap flow changed considerably between sunny and rainy days. The order of the main meteorological factors affecting the sap flux of Caragana korshinskii trees were： vapor pressure deficit 〉 solar radiation 〉 air temperature 〉 wind speed.
出处
《生态学报》
CAS
CSCD
北大核心
2006年第4期1186-1193,共8页
Acta Ecologica Sinica
基金
国家自然科学基金重点资助项目(50339030)
国家自然科学基金"中国西部环境与生态科学重大研究计划"资助项目(90202001)~~
关键词
干旱荒漠区
热脉冲技术
树干液流
木质部水分传输
柠条
arid desert region
heat pulse technique
trunk sap flow
xylem water transport
Caragana korshinskii
