Determination and discussion of average flow and sediment diversion ratio of tidal braided river reach

In the tidal reach, the flow and sediment diversion ratios in branch reach change with the flood-ebb fluctuations, so the full tidal hydrology observation is difficult. Based on two full tidal hydrology observations of Hechangzhou branch in Zhenyang reach and Taipingzhou branch in Yangzhong reach, the determination method of average flow and sediment diversion ratio is discussed. The results show that during flood tide, the flow and sediment diversion ratios are mainly influenced by the tide rising, and the diversion ratio changes greatly; the flow and sediment diversion ratios of main branch reach the largest about 2 hours before the high tide. During the ebb tide, the fluvial evolution process is dominated by the ebb tide, so the flow and sediment diversion ratios in branch reach can be expressed by the average diversion ratios in ebb tide.