An analysis of the variation of maximum flood stage of Lower Yangtze River

The study analyses the annual maximum flood stage of the Lower Yangtze River at Nanjing and the volume of runoff at Datong hydrologic station. It shows that during the most recent twenty years the higher maximum flood stages occur more frequently and the mean annual maximum flood stage has increased. The peak and the short period volume of runoff at Datong station have become larger while the average volume of runoff of longer period has been almost constant. These phenomena are explained by the change of characteristics within the catchment of Lower and Middle Yangtze River due to human activity.