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为了研究不同下垫面对土壤风蚀特征的影响,根据2009年4月19日、4月22-23日及4月30日3次沙尘事件的实际观测数据,对民勤荒漠-绿洲过渡带不同下垫面土壤风蚀特征进行了试验研究。试验结果表明,民勤荒漠绿洲过渡带各地表挟沙气流中输沙量沿垂线分布呈上段符合传统的指数递减分布规律,而近床面区35cm以下的输沙量较对应的指数分布函数预测值偏大;流沙地表90%以上的输沙量集中在近地表15cm以内,白刺灌丛沙包地带、草方格固沙带及草方格前沿芦苇荒漠带输沙量的80%左右集中在距表35cm高度范围内;不同下垫面条件对风蚀物颗粒大小分布规律的影响主要集中在近地表气流层15cm范围内,而对35～125cm高度范围内风蚀物颗粒粒径大小的影响主要在各粒径颗粒的体积分数上。风在草方格固沙带的搬运能力最弱,白刺灌丛沙包带其次,再次为芦苇荒漠带,在沙丘顶部的搬运能力最强,输沙量最大。
In order to study the influence of different underlying surface on the characteristics of soil erosion, according to the actual observation data of dust events of April 19, April 22 and April 30, 2009 and April 3, 2009, Soil erosion characteristics of different underlying surface were studied. The test results show that the distribution of sediment load along the vertical line in the sediment-laden airflow in Minqin Desert Oasis Transitional Zone shows that the upper section conforms to the traditional law of decreasing exponential distribution, whereas the sediment discharge below 35cm in the near bed area is more than the corresponding exponential distribution function The predicted value is too large; more than 90% of the sediment discharge on the surface of the quicksand is concentrated within 15cm near the surface, and about 80% of the sediment discharge of the white-thorn shrub belt, the grass-checkered sand belt and the front of the grass checkered reed desert belt And the height of 35 cm from the height of 35 cm to 125 cm. The influence of different underlying surface conditions on the particle size distribution of wind erosion was mainly in the range of 15 cm near the surface air layer, Particle size of the particle volume fraction. Wind in the grass grid with the weakest handling capacity of the weakest, white thorn sand litter followed, once again reed desert zone, the strongest in the sand dune carrying capacity, the largest amount of sediment.