杜仲蒸腾强度和气孔行为的初步研究

对太行山低山丘陵区 4a生人工杜仲林叶片的蒸腾强度和气孔导度进行测定和分析 ,结果表明 :(1)在晴朗和晴 -多云天气日 ,叶片蒸腾强度日变化呈双峰型 ,在阴天天气日 ,则呈单峰型 ;(2 )气孔导度的日变化趋势与蒸腾强度基本一致 ;(3)蒸腾强度与光量子密度、饱和水汽压差、水面蒸发等气象因子之间 ,具有较好的相关关系 ;(4)鉴于水面蒸发的测定比较方便、简单 ,因此 ,利用日水面蒸发测定值和叶面积指数去估算杜仲蒸腾耗水量 ,将具有一定的可行性

A PRELIMINARY STUDY ON LEAF TRANSPIRATION AND STOMATAL CONDUCTANCE OF EUCOMMIA ULMOIDES

The leaf transpiration ( TR ) and stomatal conductance( g s ) of 4 year old Eucommia ulmoides in the hilly land of Taihang Mountain were measured and analyzed. The results showed that: (1) the diurnal variation of TR was demonstrated double|peak curve in clear day and cloudy to clear day, and single|peak curve in overcast day; (2) the tend of diurnal variation of g s was almost the same as TR; (3) the values of TR showed good agreement with meteorological elements such as photon flux density( PFD ), saturation vapour pressure deficit of air( D ) and water surface evaporation ( EV ); (4) Because there was close relation between EV and TR ,and the approach of measuring EV was relative simple,it was feasible that TR was estimated using data on EV.