干旱区研究2017，Vol.34Issue(3)：648-654,7.DOI:10.13866/j.azr.2017.03.22
不同地下水埋深下胡杨枝条水力导度及其季节变化
Hydraulic Conductivity and Its Seasonal Variation of Populus euphratica Shoot at the Sites with Varying Groundwater Depths
摘要
Abstract
Adjustment of hydraulic structure and function plays a key role in plant acclimation to the variation of water regime.In this study, the seasonal variation of hydraulic conductivity and its related parameters of Populus euphratica shoot was observed at 3 sites along the Kayar reach in the upper reaches of the Tarim River.The sites were 0.01,3 and 40 km away from the watercourse, respectively, where the groundwater depth became deeper with the increase of distance away from the watercourse.The results showed that the averaged percentage loss of hydraulic conductivity (PLC) at all the sites was higher than 60％, and there was no significant difference between the sites,which revealed that there was a high cavitation in plant vessel under the high transpiration pressure in the study area.The xylem specific conductivity (Ks) and leaf specific conductivity (Kl) at the site with the deepest groundwater level were significantly increased, indicating an improved water use efficiency in leaves, on which the water potential gradient in plant could be lessened under water deficit.The ratio between sap area and leaf area (Hv) suggested that the Kl increase was driven by Ks rather than Hv.The seasonal variation of shoot hydraulic function was more subject to seasonal groundwater fluctuation at the site with shallow groundwater level,whereas to plant growth phenology at the site with deep groundwater level.关键词
胡杨(Populus euphratica)/地下水埋深/水力结构/环境波动Key words
Populus euphratica/groundwater depth/hydraulic structure/environmental fluctuation引用本文复制引用
蒋少伟,周多多,吴桂林,李君..不同地下水埋深下胡杨枝条水力导度及其季节变化[J].干旱区研究,2017,34(3):648-654,7.基金项目
国家重点基础研究发展计划(973计划)项目(2013CB429903) （973计划）
国家自然科学基金项目(41171037,U1403281)资助 （41171037,U1403281）
