Bankfull discharge and sediment transport in northwestern California
نویسنده
چکیده
High-magnitude, low-frequency discharges are more responsible for transporting suspended sediment and forming channels in northwestern California than in previously studied areas. Bankfull discharge and the magnitude and frequency of suspended sediment discharge were determined at five gaging stations in northwestern California. Although discharges below which 50 percent of the suspended sediment was transported and discharges which transport the greatest suspended sediment (effective discharge) occurred relatively frequently, recurrence intervals for these discharges were relatively high when compared to data from other areas. Likewise, discharges below which 90 percent of the suspended sediment was transported were also relatively infrequent. In most cases, the recurrence interval of bankfull discharge was several times greater than that of the effective discharge. This is because floodplain formation appears to be due more to overbank deposition during large sediment-laden discharges than to lateral channel migration and point bar formation.
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