FEATURES AND REGULATION OF HIGH-SEDIMENT FLOODS IN THE LOWER YELLOW RIVER

Based on data from lower Yellow River,influence of high-sediment flood on volume of deposit in the main-channel was examined.It was concluded that high-sediment flood from Hekouzhen to Longmen is the main source for main-channel depositation.Decreasing concentration,or increasing discharge or fine-sediment ratio,leads to a decrease in the deposit.realizable by regulating Xiao-lang-di reservoir in the middle reaches.Relating out-and-in ratio and fine-sediment ratio of the reservoir,it is suggested that Xiao-lang-di reservoir keep out-and-in ratio at 50%.Since the source region of the high-sediment flood has less water and more and sediment goes with flood,it is suggested that the flood water should be used on the spot.