中文摘要：

采用由热扩散树干液流技术测算得到的、周期为2个主要生长季节（4—9月）杜仲人工林蒸腾数据，结合同步观测得到降雨量以及冠层微气象数据，分析了华北石质山区10年生杜仲人工林耗水规律及水分供求关系，旨在为该地区杜仲的发展提供必要的水分生态理论依据。结果表明：（1）杜仲人工林蒸腾量（TR）呈现出明显的日内变化和日际变化特征，在晴天条件下，杜仲人工林蒸腾呈现单峰变化趋势，在多云及阴天条件下，呈现多峰变化趋势；阴天日蒸腾值明显低于晴天及多云日；杜仲蒸腾的日际变化表现为：4—5月逐渐升高，6月份左右达到高峰值，7月份逐渐降低，2005年及2006年4—9月蒸腾总量分别为268．5、212．0mm，4—9月各月蒸腾总量所占总蒸腾量的比例在2005年分别为12．3％．20．4％、20．2％、18．2％、15．9％和13．0％，在2006年分别为10．6％、21．7％、23．3％、17．4％、14．6％和12．4％；（2）TR与冠层太阳总辐射（Ra）、空气温度、湿度及风速等微气象要素有很好的复相关性（a=0．01），各月影响豫的最主要微气象因子都是Ra；（3）4—9月降雨总量（P）与TR的比值（P／TR）都大于1．0，且除4月份外，各月P／TR也大于或接近于1．0，说明降水可以满足杜仲人工林蒸腾耗水的需要。

英文摘要：

Abstract： The transpiration variation and relationship between supply and demand of water for the Eucommia ulmoides plantations in the rocky mountainous area of North China were analyzed based on the experimental data of tree sap flow, canopy, micrometeorological factors and rainfall. The trees were 10 years old. The experiment was conducted in April-September of 2005 and 2006. The aim of this study is to provide the essential evidence about water ecology for developing E. ulmoide plantations in the area. The main results are as follows ： （ 1 ） The diurnal variations of E. ulmoide plantations transpiration （TR） were demonstrated as a single-peak curve in clear day. In cloudy day, it was demonstrated as a multi-peak curve. In overcast and rain day, it was demonstrated as a multi- peak curve and much less than that in clear or cloudy day. The daily variations of transpiration （ TR ） was characterized with that TR rosed gradually in April, and reached a peak in June, fell down readily in July. In 2005 and 2006, the total TRs （ToTR）were 268.5mm,212.0 mm in the main season（ April-September）, respectively. In Apr, May, Jun, Jul, Aug and Sep, the ratio of the monthly TR to ToTR were 12.3%, 20.4%, 20.2%, 18.2%, 15.9% and 13.0% in 2005, 10.6%, 21.7%, 23.3%, 17.4%, 14.6%and 12.4% in 2006. （2） In all months during the main growth season of 2005 and 2006 , TR showed significantly compound correlated with the solar radiation （Ra）, air temperature, humidity, and wind speed over the canopy（a=0.01 ）, and Ra was the most important micro-meteorological factor effecting on TR through comparing the partial coefficient; （3） In terms of the whole growth season, the ratio of rainfall to transpiration （P/TR） was higher than 1.0 except in April. So, there was no water supply and demand conflict, or water shortage and water stress as for the main growth season in the exoeriment area.