In the paper are presented the most important results of laboratory and field investigations concerning of sandy bedload characteristics in aspects of initiation of motion and variability of bedload discharge in small lowland river, i.e. in steady and unsteady flow conditions. Investigations of critical shear stress have been carried out in laboratory flume with flat movable bottom formed by sands with different grain-size distributions. The characteristics of bedload discharge variability are presented on the basis of field investigation results conducted in the Zagożdżonka riverbed. The bedload trap provided with devices for continuous measuring and data recording was used in field investigations.

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