Combined with field survey,comparative analysis was conducted on long-term monitoring data collected in the Dongyizhigou gully and the adjacent contrast gully,which is located in the soft rock area in the upper and middle Yellow River basin.A clear trend of sediment grain-size distribution that sediment grain-size cumulative curve and total grain diameter became finer from the upper to lower stream was found in the Dongyizhigou gully,where seabuckthorn vegetation was planted and almost covered the whole gully.In contrast,the sediment grain size distribution showed no regularity at all in the control gully where no vegetation was planted.Specifically,the content of sediment with diameter larger than 1 mm was 2.0% on the gully bed of the Dongyizhigou gully,whereas it was 9.93% on that of the control gully.The analysis results showed that sand-fixing capability of seabuckthorn vegetation imposed a sediment sieve effect on the sediment transportation in the gully bed.