国槐枝叶水分特征及其对树干边材液流的影响  

Water characteristics of Sophora japonica twig and leaf and its impact on sap flow

作　　者：李广德[1] 王晓辉[2] 贾黎明[1] 沈繁宜[2] 

机构地区：[1]北京林业大学省部共建森林培育与保护教育部重点实验室 [2]北京林业大学理学院,北京100083

出　　处：《中南林业科技大学学报》2010年第1期23-28,33,共7页Journal of Central South University of Forestry & Technology

基　　金：国家自然基金项目(30371147);北京市自然科学基金项目(6052016);北京市教育委员会学科建设与研究生培养项目-北京城市生态环境建设产学研联合培养研究生基地(BL2007)

摘　　要：为探明国槐Sophora japonica组织含水量、水势、水容等枝叶水分特征及其对树干边材液流的调节和影响,于2007年3月下旬至2008年3月下旬利用热扩散式边材液流检测技术(TDP)、压力室技术等对生长在北京林业大学校园内的国槐树干边材液流、组织含水量、水势、水容等进行了系统研究。结果表明:城市环境下,(1)国槐树干边材液流速率日变化春季和夏季呈双峰曲线,秋季呈单峰曲线;液流峰值出现时间春季最早,夏季次之,秋季最晚;春季和秋季液流速率峰值较夏季高,但峰值维持时间夏季较春、秋两季长。(2)国槐枝条与叶片绝对含水量、水势、水容具有相似的日变化规律,但不同季节日变化有所差异。(3)整个生长季,国槐含水量、水势、水容的大小排序为春季>夏季>秋季;枝条平均含水量(52.12±2.59)%<叶片平均含水量(69.59±4.64)%;枝条平均水势(-1.70±0.74)MPa>叶片平均水势(-1.87±0.65)MPa;枝条水容(1.488±3.060)g.cm-3.MPa-1>叶片水容(5.86±6.70)×10-3g.cm-3.MPa-1。(4)国槐组织水容日变化与树干边材液流速率日变化反向相关,国槐枝叶含水量、水势、水容等共同作用和调节其蒸腾耗水。In order to clarify the twig and leaf water characteristics of of Sophora japonica and its regulating and impacting on sap flow,sap flow velocity（Vsf）,twig ＆ leaf absoluteness water content（CAWC）,water potential（ψ） and water capacitance（C） were measured using thermal dissipation sap flow velocity probe（TDP） and pressure chamber on the campus of Beijing Forestry University（39°46′N,116°19′E） from the last ten-day period of March,2007 to the same period of 2008.The results show that（1） diurnal fluctuation of S.japonica Vsfwas a double-peaked curve in spring and summer,and single-peaked curve in autumn;the appearing time of Vsfpeak value later from spring to autumn;Vsfpeak value was higher in spring and autumn than that in summer,but the sustaining time of Vsfpeak value in summer was longer than that in spring and autumn;（2） It was consistent for the diurnal fluctuation of S.japonica twig ＆ leaf CAWC,ψ,and C,but differences in different seasons;（3） In the entire growth season,the ordination of average twig ＆ leaf value of CAWC,ψ,and C was Spring〉Summer〉Autumn.The average twig CAWC value（52.12±2.59）% of S.japonica was smaller than leaf（69.59±4.64）%, but the average twig ψ,and C value was higher than leaf,which was（-1.70±0.74） MPa,（-1.87±0.65） MPa,and（1.488±3.06） g·cm^-3MPa^-1,（5.86±6.70）×10^-3 g·cm^-3MPa^-1 respectively;（4） The daily variation regularity of sapflow and twig ＆ leaf water capacitance of S.japonica was opposite to each other.In conclusion,water transpiration and use of S.japonica was regulated and controlled together by twig and leaf absoluteness water content,water potential,and water capacitance.

关 键 词：植物生理学 国槐 边材液流 水势 水容 调控作用 

分 类 号：Q945.17[生物学—植物学]