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中国沙漠 ›› 2007, Vol. 27 ›› Issue (1): 25-31.

• 沙漠与沙漠化 • 上一篇    下一篇

呼伦贝尔沙质草原风蚀坑研究(Ⅲ): 微地貌和土层的影响

张德平1,2, 孙宏伟3, 王效科1, 冯宗炜1   

  1. 1.中国科学院生态环境研究中心系统生态开放研究室,北京 100085; 2.呼伦贝尔市国土资源局,内蒙古 呼伦贝尔 021008; 3.呼伦贝尔学院小学教育分院,内蒙古 呼伦贝尔 021000
  • 收稿日期:2005-07-08 修回日期:2005-09-23 出版日期:2007-01-20 发布日期:2007-01-20

HulunBuir Sandy Grassland Blowouts (Ⅲ): Influence of Soil Layer and Microrelief

ZHANG A MungkDalai1,2, WANG Xiao-ke1, U. Hurrle3, FENG Zong-wei1   

  1. 1.Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; 2.Bureau of Land and Resources of HulunBuir City, HulunBuir 021008, Inner Mongolia, China; 3.Primary Education College of HulunBuir University,HulunBuir 021000, Inner Mongolia, China
  • Received:2005-07-08 Revised:2005-09-23 Online:2007-01-20 Published:2007-01-20

摘要: 采用剖面测量,沿剖面选取不同微地貌部位测量土层厚度、坚实度、粒度构成,并进行室内统计比较和分析的方法,对呼伦贝尔沙质草原区风蚀坑的发育受微地貌部位和土层控制的情况进行了研究。发现在接近自然状态下风蚀坑主要发育于西南坡和南坡的上部和中部;由于翻耕、机动车道路等人类活动诱发,也形成于平坦的草地,北坡和东坡甚至低地。沙质草原区的土层中部存在一个粗化层,在失去草被和上部的土壤-根系层保护时特别容易遭受风蚀的侵害,形成风沙流破坏钙积层并导致风蚀坑的形成。沙质草原是生态地质环境脆弱区,呼伦贝尔沙质草原区的西坡、南坡的中上部,梁岗丘等微地貌部位是风蚀沙化的危险地带。干旱半干旱气候区沙质草原的土层是稀缺的自然资源,地表土壤-植物根系层是珍贵的生态系统。保护地表土层对于保护草地资源和生态环境,以及沙漠化防治具有极端重要性。

关键词: 风蚀坑, 微地形, 地表土层, 沙土楔, 沙漠化, 风沙地貌

Abstract: Thickness, compactness and grain composition of top soil layer were tested along sections across west Hailar, HulunBuir sandy grassland to determine how blowouts are controlled by microrelief and top soil layer. It was discovered that when west wind prevails, blowouts mostly develop in the upper to middle parts of SW and S slopes. Blowouts could also develop in flat sandy grasslands, N and E slopes, and even in low lands when initiated by human activities of plowing and motor vehicle natural roads which cut soil layer and let the underlying sand expose to and gain energy from strong wind. There is a coarsened layer in middle of top soil layer that is considered to be the result of an ancient aeolian erosion process. The coarsened layer, loose and low in compactness, is vulnerable to wind erosion and easy to form sand flow to break the calcic horizon the bottom soil, crucial to sandy grassland blowout formation. Sandy grassland is fragile geo-ecosystem. The middle and upper parts of W, SW, and S slopes, ridges and hillocks on grasslands are dangerous regions for aeolian erosion. The top soil layer is the rarest natural resource, and the soil-root layer is the most precious ecosystem on arid and semiarid sandy grasslands. The protection of top soil layer has utter most importance in protection of grassland resources and ecosystem, and in prevention of sandy desertification.

Key words: blowout, microrelief, top soil layer, sandy soil wedge, sandy desertification, aeolian geomorphology

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