辽西地区3种灌木的水分利用效率和叶性状特征

大扁杏、中国沙棘和黑果腺肋花楸是辽西地区的主要造林灌木树种。本文利用稳定同位素技术测定3种灌木叶片的稳定碳同位素比值（δ13C值），分析它们的长期水分利用效率（WUE）；并结合3种灌木的叶性状研究，分析水分利用效率与叶性状各因子之间的相关性，探讨3个造林灌木树种在水分胁迫条件下的生理响应特征。结果表明：3种灌木的水分利用效率差异显著（P＆lt;0.05），其中，中国沙棘水分利用效率最高，大扁杏次之，黑果腺肋花楸最低；叶性状各因子之间相关性显著；水分利用效率与单位重量叶氮浓度（Nmas ）、比叶面积（SLA）和全碳含量呈正相关，与单位面积叶氮浓度（Narea）和C/N呈负相关。水分利用效率和叶性状特征的研究结果表明3种灌木分别采取了不同的生理策略来适应水分胁迫环境。

Water Use Efficiency and Leaf Traits of Three Afforestation Shrubs in Western Liaoning

Prunus armeniaca, Hippophae rhamnoides ssp. sinensis and Aronia melanocarpa are main shrubs for afforestation in western Liaoning. Stable isotope technique was used to test the δ13C value for evaluateing the water use efficiency （WUE） of three shrubs, and the relationship between WUE and leaf traits were studied for discussing the physiological strategy of three shrubs in water stress condi-tion. The difference of leaf δ13C value among three shrubs was significant; H. rhamnoides ssp. sinensis has exclusively higher WUE than P. armeniaca and A. melanocarpa, and the WUE of P. armeniaca was higher than A. melanocarpa. There was significant correlation among leaf traits. The WUE was positively correlated with Nmass, SLA and total C content, and was negative correlation with Narea and C/N ratio. The WUE and leaf traits suggested that three shrubs adapted to water stress condition by different physiological strategies.