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中国沙漠 ›› 2002, Vol. 22 ›› Issue (4): 344-349.

• 研究论文 • 上一篇    下一篇

沙漠地区人工固沙植被对土壤温度与土壤导温率的影响

王新平1, 李新荣1, 张景光1, 周海燕1, Berndtsson R2   

  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. Department of Water Resources Engineering, Lund University, S-22100 Lund, Sweden
  • 收稿日期:2001-04-15 修回日期:2002-03-10 出版日期:2002-08-20 发布日期:2002-08-20
  • 作者简介:王新平(1969-),男(汉族),甘肃通渭人,在读博士,从事干旱区水文过程研究。
  • 基金资助:
    国家重大基础研究发展规划项目"中国北方沙漠化过程及其防治研究"(G2000048704);中国科学院寒区旱区环境与工程研究所知识创新工程项目(CACX210031);中国科学院沙坡头沙漠试验研究站开放基金(200025)共同资助

Variation of Soil Temperature and Thermal Diffusivity in Vegetated and Bare Sand Dunes in Arid Desert Region

WANG Xin-ping1, LI Xin-rong1, ZHANG Jing-guang1, ZHOU Hai-yan1, Berndtsson R2   

  1. 1. Shapotou Desert Experimental Research Station, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences. Lanzhou 730000;
    2. Department of Wate Resources Engineering, Lund University, S-22100 Lund, Sweden
  • Received:2001-04-15 Revised:2002-03-10 Online:2002-08-20 Published:2002-08-20

摘要: 通过分析人工固沙植被区与流动沙丘区不同部位(沙丘迎风坡、丘间低地、沙丘背风坡)各层土壤温度梯度分布,及其月平均值变化与日变化特点,计算不同地表覆盖(人工植被与裸沙区)条件下的沙土导温率。结果表明,沙坡头地区7~ 10月平均地温变化的振幅,在地面约为16.2 ℃,振幅变化随深度的递增而迅速减小。在0.05m深度处,地温年振幅为地面振幅的一半。7~ 10月中地温最高最低出现的月份,随深度增加都呈滞后现象,但滞后的情况两者并不相同。另外,在20cm以下深度内,7~ 10月月平均温度都高于0 ℃。当观测深度按算术级数增加时,地温日振幅则以几何级数减小。尽管地温振幅日变化因天气情况不同大有差别,在相同的气象条件(连续四日晴天)下的研究发现,下垫面的影响作用不容忽视,尤其是由于植被覆盖度的差异而引起的地温日振幅与地温剖面分布变化。根据1992年8月观测记录,流沙区丘间地温日振幅最高达26.2℃ (表层),最小值只有1.8 ℃ (1m深)。固沙植被区丘间低地最高日振幅为25.9 ℃ (表层),最低值4.3 ℃ (1m深)。植被区地表层温度变幅小于流沙区,而深层温度波动显著。在5cm深度处,植被区地温降至最低值的时间滞后于流沙区2h以上,20cm处植被区地温达到最大值的时间比流沙区提前2~4h。

关键词: 土壤温度振幅, 沙漠地区, 人工植被, 固定沙丘

Abstract: The gradients of soil temperature (ST) in both vegetated and bare sand area were investigated. Results indicate that daily fluctuation and mean monthly amplitude of ST are influenced by soil depths, terrains and plant coverage significantly. Soil temperature amplitude tends to decrease in geometric series as the observation depth increases. The mean monthly soil temperature amplitude from July to October was 16.2 ℃ on the surface, and at the depth of 5 cm, it decreased to 7.28 ℃. The mean monthly soil temperature was always above 0 ℃ below 20 cm of the ground surface. Daily soil temperature fluctuation has larger amplitude value on the surface of bare sand than that of the vegetated one. In bare sand dune, there was a declined trend of amplitude till 1 m, while in the vegetated region, arbitrary temperature amplitude due to roots activities.

Key words: soil temperature amplitude, arid desert region, artificial vegetation, fixed sand dunes

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