黑河下游河岸林植物水分来源初步研究 |
|
关键词:stable oxygen isotope Heihe basin riparian forest water sources |
基金项目:中国科学院西部行动计划项目(二期)(编号:KZCX2-XB2-04-03);中国科学院2007年度“西部之光”人才培养计划博士资助项目;中国博士后科学基金面上资助项目(编号:20070420135) |
|
摘要点击次数: 3412 |
全文下载次数: 4753 |
摘要: |
A Preliminary Study of Water Sources of Riparian Plants in the Lower Reaches of the Heihe Basin |
Using the multiple source mass-balance isotopic approach,the authors tentatively evaluated water sources of riparian forest plants in the extremely arid region along the lower reaches of the Heihe River basin by analyzing the stable oxygen isotope(δ18O)of plant water and the potential water sources such as soil water,river water and groundwater and calculating probable contributions of multiple potential sources to total plant.The results show that there exist significant evaporative isotopic fractionation during the process of hydraulic infiltration from river water to groundwater and soil water and that of hydraulic redistribution in soil profiles in the riparian forest ecological system along the lower reaches of the Heihe River basin. The δ18O values of Populus euphratica Oliv., Tamarix ramosissma and Sophora alopecuroides are -6.43‰, -6.28‰ and -6.61‰ respectively, being relatively negative in comparison with the values of Sonchus oleraceus Linn (-5.14‰) and Herba Taraxaci (-5.52‰), Frequency histograms produced from the multiple source mass-balance analysis have revealed that the Populus euphratica Oliv. and Tamarix ramosissma obtained over 93% and 90% of their water from groundwater. However, the Sophora alopecuroides obtained more than 97% of its water from the soil layer about 80 cm in depth.In additon to obtaining water from the upper 0~20 cm, Sonchus oleraceus Linn and Herba Taraxaci may have other water sources in the extermely arid region. The results obtained by the authors show that in the riparian forest of the lower reaches of the Heihe River Basin, the growth of wood and shrub plants mainly depends on the groudwater, while the redistributed soil water from the groudnwater seems to be the main water source of the herbage. |
ZHAO Liang-ju,XIAO Hong-lang,CHENG Guo-dong,SONG Yao-yuang,ZHAO Laing,LI Cai-zhi,YANG Qiu.2008.A Preliminary Study of Water Sources of Riparian Plants in the Lower Reaches of the Heihe Basin[J].Acta Geoscientica Sinica,29(6):709-718. |
查看全文 查看/发表评论 下载PDF阅读器 |
|
|
|
|
|