%0 Journal Article
%T HulunBuir Sandy Grassland Blowouts ( Ⅲ ): Influence of Soil Layer and Microrelief<br>呼伦贝尔沙质草原风蚀坑研究（Ⅲ）: 微地貌和土层的影响
%A ZHANG A MungkDalai
%A WANG Xiao-ke
%A U Hurrle
%A FENG Zong-wei
%A <br>张德平
%A 孙宏伟
%A 王效科
%A 冯宗炜
%J 中国沙漠
%D 2007
%I 
%X 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-ecosystern. 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.
%K blowout
%K microrelief
%K top soil layer
%K sandy soil wedge
%K sandy desertification
%K aeolian geomorphology<br>风蚀坑
%K 微地形
%K 地表土层
%K 沙土楔
%K 沙漠化
%K 风沙地貌
%U http://www.alljournals.cn/get_abstract_url.aspx?pcid=E62459D214FD64A3C8082E4ED1ABABED5711027BBBDDD35B&cid=869B153A4C6B5B85&jid=F62EDFC6E63C5D025C6AE9D0171B7C05&aid=1513D5C941792E92&yid=A732AF04DDA03BB3&vid=DB817633AA4F79B9&iid=CA4FD0336C81A37A&sid=C5154311167311FE&eid=4AD960B5AD2D111A&journal_id=1000-694X&journal_name=中国沙漠&referenced_num=4&reference_num=20