北京山区侧柏人工林水分利用效率及其影响因素  

Water use efficiency and its influencing factors of Platycladus orientalis plantation in Beijing mountains area,China

作　　者：郑鹏飞 余新晓[1] 贾国栋[1] 刘自强[1] 张永娥[1] 朱栩辉 ZHENG Peng-fei;YU Xin-xiao;JIA Guo-dong;LIU Zi-qiang;ZHANG Yong-e;ZHU Xu-hui(Ministry of Education Key Laboratory of Soil and Water Conservation and Desertification Combating,Beijing Forestry University,Beijing 100083,China)

机构地区：[1]北京林业大学水土保持与荒漠化防治教育部重点实验室,北京100083

出　　处：《应用生态学报》2019年第3期727-734,共8页Chinese Journal of Applied Ecology

基　　金：国家自然科学基金重点项目(41430747;41877152);北京市教委项目(PXM2018_014207_000024)资助~~

摘　　要：水分利用效率(WUE)是衡量植物抗旱性的一个重要指标,研究其动态变化及其影响因素能为北京山区植被建设提供参考.本研究基于稳定碳同位素技术,通过测定北京山区侧柏人工林在生长季的水分利用效率,探究气象因子、土壤因子和大气CO_2浓度对侧柏短期WUE的影响.结果表明:1)侧柏生长季内的短期WUE呈现先降低后增加的变化特征,7月侧柏的短期WUE最低(2.69 mmol·mol^(-1)),10月侧柏的短期WUE最高(13.88 mmol·mol^(-1)).2)叶内外水汽压差(VPD)、大气温度(T_a)、土壤湿度(M_s)、空气相对湿度(RH)和大气CO_2浓度(C_a)是植物WUE的影响因素,5个影响因素对侧柏短期WUE变化的累计解释率达89.7%;太阳辐射(R_a)和风速(W_s)与侧柏短期WUE没有显著关系.3)VPD和T_a是影响侧柏短期WUE的主要因素,两者组成的主成分可以解释53.9%的侧柏短期WUE变化,其中VPD对侧柏短期WUE的影响高于T_a;M_s和RH是影响侧柏短期WUE的次要因素,两者组成的主成分可以解释25.4%的侧柏短期WUE变化,其中M_s对植物短期WUE的影响高于RH;C_a对侧柏短期WUE的影响较小,主要由C_a和T_a组成的主成分可以解释10.3%的侧柏短期WUE变化.Water use efficiency (WUE) is an important index to evaluate plant drought resistance. Studying the dynamics of WUE and its influencing factors can provide reference for the vegetation restoration in Beijing mountainous area. We measured WUE of Platycladus orientalis in growing season and investigated the influence of meteorological factors, soil factors, and atmospheric CO2 concentration on WUE, based on the stable carbon isotope techniques. The results showed that: 1) The short-term WUE decreased and then increased in the growing season, with minimum value (2.69 mmol·mol^-1) in July and maximum value (13.88 mmol·mol^-1) in October. 2) The vapor pressure deficit (VPD) had the most significant impacts on WUE, followed by air temperature (Ta), soil moisture (Ms), relative humidity (RH), and atmospheric CO2 concentration (Ca), explaining 89.7% of the total variance. Solar radiation (Ra) and wind speed (Ws) had no impacts on WUE. 3) VPD and Ta are the most two important factors influencing short-term WUE, explaining 53.9% of the total variance. The effects of VPD on short-term WUE was higher than that of Ta. Ms and RH were the second important factors of the short-term WUE, explaining 25.4% of the total variance. The effects of Ms on short-term WUE was higher than that of RH. Ca had little effect on the short-term WUE and could explain 10.3% of the total variance.

关 键 词：侧柏 季节变化 水分利用效率(WUE) 影响贡献率 

分 类 号：S791.38[农业科学—林木遗传育种]