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| Air flow dynamics of the blowout trough in the Hulun Buir sandy grassland |
| Wang Shuai1,2,Hasi Eerdun2 |
| 1.Zhejiang Institute of Hydraulics and Estuary,310020,Hangzhou;2.College of Resources Science and Technology;State Key Laboratory of Earth Surface Processes and Resource Ecology,Beijing Normal University,100875,Beijing: China |
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Abstract Blowout trough is the best surface expression of the aeolian processes responding to regional climatic changes and human ctivities,which is also the driving force of grassland landscape heterogeneity.When the wind approaches to the blowout trough parallel to the thread orientation,the velocity is become slow because of the expansion,and until jet usually occur at the 3/4 of the central line of the deflation basin.The results show that more and more air flow was sucked into the blowout trough,and the rim of the blowout trough is usually eroded by this process,and flow deceleration and expansion occur to the depositional lobe.When the wind approaches to the blowout trough obliquely,the air flow is usually extremely turbulent,and air flow was sucked into the blowout trough from the rim,because the erosion wall is very steep,so the air flow is steered as return flow,and erodes the coming wall and deposited on the opposite wall.Blowout trough morphologies are explained as a function of these air flow patterns.
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Received: 09 April 2008
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