%0 Journal Article
%T The sap flow dynamics of Caragana korshinskii and the influence of environmental factors in semi-arid region of the Loess Plateau<br>黄土高原半干旱区柠条(Caragana korshinskii)树干液流动态及其影响因子
%A XIA Yong-Qiu
%A SHAO Ming-An
%A <br>夏永秋
%A 邵明安
%J 生态学报
%D 2008
%I 
%X Measurements of sap flow were made in two 20-year-old Caragana korshinskii stands that largely differed in tree density for the period of 13-25 June 2006 in Liudaogou catchment in Loess Plateau of China. Soil water content, air temperature, relative humidity, solar radiation, wind speed, grass reference evapotranspiration (ET0), and water vapor pressure deficit (VPD) were also measured, and the actual canopy conductance was calculated from the inverted Penman-Monteith equation based on the actual data of stand transpiration. The results showed that the sap flows were closely coupled to the changing weather conditions except wind speed and could be tightly fitted to a simple linear equation of radiation. The transpiration from the two studied stands was effectively scaled by leaf area index. Canopy transpiration of the high density stand with LAI 2.3 reached in averaged of 3.83 mm d-1m-2 compared with 1.64 mm d-1m-2 for the stand with LAI 1.1 of the low density stand. The analysis of canopy conductance showed no meaningful responses to radiation, air temperature and ET0 but excellent fits to VPD and relative humidity in the case of soil drought. On the contrary, no correlativity of canopy conductance to VPD and relative humidity was observed in case of soil wet condition, though canopy conductance was tightly fitted to radiation, air temperature and ET0.
%K the Loess Plateau
%K Caragana korshinskii
%K sap flow
%K canopy conductance
%K Leaf Area Index
%K climatic factors<br>黄土高原
%K 柠条(Caragana
%K korshinskii)
%K 树干液流
%K 冠层导度
%K 叶面积指数
%K 气象因子
%K 黄土高原半干旱区
%K 柠条
%K 树干液流动态
%K 影响因子
%K the
%K Loess
%K Plateau
%K region
%K environmental
%K factors
%K influence
%K dynamics
%K 相关性
%K 水汽压
%K 存在
%K 关系
%K 气象因子
%K 叶面积指数
%K 蒸腾量
%K 估测
%K 线性表达式
%K 树木
%K 结果
%U http://www.alljournals.cn/get_abstract_url.aspx?pcid=90BA3D13E7F3BC869AC96FB3DA594E3FE34FBF7B8BC0E591&jid=FE163E5DB2274E5937319DE98913EC37&aid=2DF901A6EE02F5232D6B1D3E1C96FB61&yid=67289AFF6305E306&vid=D3E34374A0D77D7F&iid=E158A972A605785F&sid=FFFB69BAAED96604&eid=687F936229D80BADA5F733E72653D9A7&journal_id=1000-0933&journal_name=生态学报&referenced_num=0&reference_num=24