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中国沙漠 ›› 2010, Vol. 30 ›› Issue (5): 1108-1113.

• 生物土壤与生态 • 上一篇    下一篇

荒漠灌丛树干茎流及其入渗、再分配特征

王正宁1,2, 王新平1*   

  1. 1.中国科学院 寒区旱区环境与工程研究所 沙坡头沙漠试验研究站, 甘肃 兰州 730000; 2.中国科学院 研究生院, 北京 100049
  • 收稿日期:2010-01-27 修回日期:2010-03-01 出版日期:2010-09-20 发布日期:2010-09-20

Stemflow of Caragana korshinskii and its Infiltration and Redistribution in Desert Environment

WANG Zheng-ning1,2, WANG Xin-ping1   

  1. 1.Shapotou Desert Experimental Research Station, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, China; 2.Graduate University of Chinese Academy of Sciences, Beijing 100049, China
  • Received:2010-01-27 Revised:2010-03-01 Online:2010-09-20 Published:2010-09-20

摘要: 运用铝箔收集法测定了荒漠灌木柠条(Caragana korshinskii Kom.)树干茎流;利用时域反射仪连续测量土壤剖面水分含量,分析树干茎流影响下柠条根际区水分入渗与再分配过程。结果表明,柠条灌丛产生树干茎流需要2.2 mm的前期降雨量,树干茎流占降雨量的7.9%,平均汇流率是89.8。土壤表层含水率对降雨过程响应明显; 当降雨量达到6 mm时,树干茎流有利于增加根际区土壤水分增量,补充深层土壤水分,对荒漠植被在干旱条件下存活起着重要作用。

关键词: 柠条, 汇流率, 湿润锋, 土壤水分增量

Abstract: Stemflow is important in sustaining the stabilization of desert ecosystems, where precipitation is the critical source of water replenishment. Stemflow of Caragana korshinskii, a kind of xerophytic shrub, was collected by aluminum foil collar at the re-vegetated sand dunes in the Shapotou desert ecosystem of the northwestern China. The 20 probes of Time Domain Reflectometry (TDR) were inserted horizontally into the soil profile near C. korshinskii root at different depths to record volumetric soil moisture by hourly intervals. Stemflow of C. korshinskii, expressed as an equivalent water depth per unit projected crown area, was averaged by 7.9% of the gross precipitation and the average funnelling ratio was 89.8. Amount of 2.2 mm precipitation was necessary for the generation of the stemflow of C. korshinskii. The surface soil moisture was strongly correlated with individual rainfall. Stemflow was helpful to increase the soil moisture increment around the root area and replenish the deeper soil layers moisture only when rainfall reached 6 mm. The water infiltrated to the deeper soil layer played an important role in plant surviving in the arid environment.

Key words: Caragana korshinskii, funnelling ratio, wetting front, soil moisture increment

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