Study on sediment transport potential and contribution of wind-blown sand into Yellow River in Xiliugou Valley and middle reaches of Yellow River Basin
In this study,the Xiliugou sandstorm area,one of the top ten tributaries,was selected as the study area.Through the combination of field monitoring and indoor analysis,the characteristics of wind conditions and sand transport potential in the study area were analyzed.At the same time,the observation of sandstorm flow activities was carried out to measure the sand transport fluxes on different underlying surfaces along the river basin.The results indicated that:(1)The study area is classified as a medium wind energy environment,with an average annual sand-driving wind speed of 6.41m/s,an average annual sand-driving wind frequency of 17.85%,and a maximum wind speed of 11.37m/s.(2)The direction of synthetic sediment transport potential tends to remained consistent at different time scales,primarily in the southeast direction(SE,SSE).The annual variability index for direction belonged to the medium range,and the annual synthetic sediment transport potential direction(RDD)was towards the SSE direction.This directly results in a significant amount of sediment being inputted into the river.(3)The vertical sediment transported fluxes of different underlying surfaces were significantly distinct,with wind-driven sand accounting for 77.09%in moving sand,15.30%in semi-fixed sand,and 7.61%in fixed sand,respectively.The variation of the vertical line of surface sediment transport rate indicated a strong exponential relationship between the total sediment transport rate of different underlying surfaces and wind speed.Therefore,the relationship between sediment transport rate(qv),duration of sand-driving wind(h),and length of section(dm)is utilized to estimate that the average annual total amount of yellow dust in Xiliugou Basin was approximately 8.09x105t/a.This paper aims to explore the coupling relationship between sand transport rate and wind speed on different underlying surfaces in Xiliugou Basin,in order to provide a data basis for preventing and controlling wind-blown sand into the Yellow River Basin and reducing safety risks caused by it.
Yellow River BasinXiliugou Valleysediment transport potentialsediment dischargewind sand into yellow