Hydrological and sediment-transport characteristics of the middle and lower Yangtze River: Analysis from a magnitude-frequency perspective

•Flow frequency distribution and sediment-transport rate were influenced by floodplain lake.•Frequency distribution of medium-high flow agreed well with broken power law.•Sediment-transport rating curve deviated from power law at high flow.•Effective discharges decreased by 10%–20% indicating flood channel shrinkage.