摘要
运用Granier热扩散探针技术,测定了中间锦鸡儿整株丛树干液流日进程及其月动态变化,并分析了树干液流变化与同步测定的太阳辐射强度、空气温度、空气相对湿度、土壤温度等环境因子之间的关系。结果表明:中间锦鸡儿整株丛树干液流昼夜变化可分为4个明显的阶段:1)液流量迅速上升阶段;2)液流量最大的稳定阶段;3)液流量迅速降低阶段;4)液流量较小的稳定阶段。中间锦鸡儿整株丛树干液流量的月变化特征,除10月有明显下降外,其余各月的树干液流量并没有明显的差异;在5月、7月、9月树干液流的变化都滞后于太阳辐射而提前于水汽压亏缺,存在一定的时滞现象。从整株丛树干液流量和环境因子的相关关系来看,太阳辐射强度在该研究区是影响中间锦鸡儿整株丛树干液流的关键因子;在遇到突发性降雨时,中间锦鸡儿整株丛树干液流量会随着降水的增加而迅速升高,但时间上要滞后于降水量达到最大值的时间。
In order to characterize the water consumption by Caragana intermedia,an excellent wind-breaking and sand-fixing shrub species widely planted in Inner Mongolia,its whole-plant transpiration was monthly measured by using Granier＇s thermal dissipation probe.Meanwhile,the environmental factors such as solar radiation around sample plant,air temperature,air relative humidity,and soil temperature were also measured.The whole-plant transpiration had a diurnal variation with four distinct phases,i.e.,rapid ascending phase,stationary high phase,rapid descending phase,and stationary low phase.Except for October,in which the trunk sap flow had a marked decrease,there was no significant difference in the sap flow in other months.In May,July,and September,the variation of trunk sap flow lagged behind solar radiation,but advanced vapor pressure deficit.Solar radiation was the key factor affecting the transpiration.Under sudden precipitation,a rapid increase of the whole-plant sap flux was observed,but the increase lagged behind the peak time of the precipitation.
出处
《生态学杂志》
CAS
CSCD
北大核心
2010年第3期420-426,共7页
Chinese Journal of Ecology
基金
国家自然科学基金项目(30660028
30660034
40841018)
教育部"春晖计划"科研资助项目(E-2004-2-15034)
关键词
中间锦鸡儿
树干液流
热扩散探针技术
时滞现象
Caragana intermedia
trunk sap flow
thermal dissipation probe method
time lag
