沙柳稳定碳同位素值的特点及其水分利用效率  

Study on δ^(13)C Values of Desert Plant Salix psammophila and Water Use Efficiency

作　　者：刘海燕[1] 李吉跃[1] 赵燕[1] 黄看看[1] 

机构地区：[1]北京林业大学省部共建森林培养与保护教育部重点实验室,北京100083

出　　处：《干旱区研究》2008年第4期514-518,共5页Arid Zone Research

基　　金：国家自然科学基金项目(30671675);北京市科委项目“北京城市园林绿化耐旱、节水园林植物筛选和应用研究”;JD100220535“森林培育与保护实验室”北京城市绿地水分经济生态的研究课题资助

摘　　要：通过对沙柳5个种源苗木叶片不同月份稳定碳同位素组成(1δ3C)的测定,研究不同种源沙柳δ13C值的特点,试图找出影响δ13C值季节变化的关键环境因子。结果表明:沙柳碳同位素值在-26.753‰^-29.915‰之间变化,其中,乌审旗和榆林种源1δ3C值较高,表明在该试验条件下具有较高的水分利用效率;叶片与枝条相比,δ13C值在6月和8月差异明显,达到0.930‰~2.469‰;而枝条的碳同位素值差异较小,为0.032‰~0.838‰;沙柳δ13C值在不同月份间有显著性差异,6月δ13C值明显高于8月;在将各环境因子分离开的情况下,主要研究了大气相对湿度对植物的1δ3C值季节变化的影响,结果显示,δ13C值随大气相对湿度的降低而偏重。By measuring the values of stable carbon isotope in leaves and branches of Salix psammophila from five provenances, in this paper the characteristics of δ^13C values of different organs of Salix psammophila and the relationship between the δ^13C values and the environmental factors under natural conditions are researched. The results show that the δ^13C values of Salix psammophila vary in a range from -26. 753‰ to -29. 915%o, in which the δ^13C values of Salix psammophila from the provenances in Wushen Bonner and Yulin are high, which reveals that the water use efficiency under the experimental conditions is high. The δ^13C values of leaves in June are significantly different from that in August, and the difference is as high as 0.930‰～2. 469‰. Compared with leaves, the difference of δ^13C values of branches in these two months is not so high, and it is only 0.032‰ ～ 0.838‰. Under the conditions of separating air relative humility from other environmental factors, it can be concluded that air humility is an important environmental factor resulting in the seasonal variation of δ^13C values of Salix psammophila plants, and the δ^13C value is reduced with the decrease of air relative humility.

关 键 词：沙柳 稳定碳同位素δ^13C 水分利用效率 季节变化 

分 类 号：S793[农业科学—林木遗传育种]