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中国沙漠 ›› 2002, Vol. 22 ›› Issue (6): 559-565.

• 研究论文 • 上一篇    下一篇

中国沙漠地区降尘特征与影响因素分析

樊恒文, 肖洪浪, 段争虎, 李新荣, 李涛, 李金贵   

  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
  • 收稿日期:2002-03-14 修回日期:2002-09-01 出版日期:2002-12-20 发布日期:2002-12-20
  • 作者简介:樊恒文(1963-),男(汉族),甘肃庆阳人,助理研究员,主要从事沙漠化治理研究。
  • 基金资助:
    中国科学院寒区旱区环境与工程研究所创新项目(210028);国家自然科学基金项目(40005002)资助

Dustfall Characteristics and Affect Factors in Chinese Desert Region

FAN Heng-wen, XIAO Hong-lang, DUAN Zhen-hu, LI Xin-rong, LI Tao, LI Jin-gui   

  1. Shapotou Desert Research and Experiment Station, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, China
  • Received:2002-03-14 Revised:2002-09-01 Online:2002-12-20 Published:2002-12-20

摘要: 1991-1998年期间先后使用积尘器在4个地形剖面上监测了沙坡头地区的降尘过程。降尘沉积速率平均4866kg·hm-2·a-1,降尘沉积具有明显的时空分异规律,月最大沉积于每年的5月发生在丘间低地,这是因为每年的5月份既是区域冬夏季风场的转换季节,又是人类活动破坏地表的时期,并受地貌沉积模式的影响;较小的月沉积于冬季出现在丘顶部位。降尘的粒径集中在2~250μm,极细砂占总量的3716%,沉积物属于砂壤质地。Si、Al、Fe、Ca、K、Na、Mg、Ti等8个元素构成检出元素总量的99.53%。10~250μm的尘屑中含有30种重矿物,其中易风化矿物占56.75%~74.32%。风尘相关分析发现月降尘量与每月>5m·s-1风速的次数有良好的相关性。

关键词: 降尘沉积, 时空模式, 元素和重矿物, 沙漠黄土过渡带

Abstract: The dust-fall depositions were monitored with dust trappers on the four topographical transections in the Shapotou area from 1991 to 1998. The deposition velocity averaged 4866 kg·hm-2 yearly. The dust deposition had obvious temporal and spatial patterns. The maximal monthly depositions were observed during May of every year at the dune hollows, because the May of every year was both a conversion season from winter wind to summer wind in the region and a period when human activities destroyed the surface, and topographical pattern influenced the deposition. Smaller depositions appeared on the crests during the winter. The particle size of the deposition distributed between 2~250 μm. The very fine sand occupied 37.16% of the total deposition. The texture of the deposition belonged sandy loam. The eight elements, Si, Al, Fe, Ca, K, Na, Mg and Ti made up of 99.53% of the element total. In the particles within 10~250 μm contained 30 heavy minerals, in which weathering minerals occupied 56.75%~74.32%. The relative analysis between wind factors and dust deposition displayed that there was a good relativity between the monthly depositions and the monthly times of > 5 m·s-1 wind speed.

Key words: aeolian deposition, temporal and spatial pattern, element and heavy mineral, trans-zone between desert and loess plateau

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