淮河干流蚌埠闸上游径流变化趋势分析OA

To avoid difficulties in deciding the timing of water storage and release,as well as water resource wastage caused by the complexity of upstream inflow processes,this paper is based on the daily runoff data from 1950 to 2016 recorded at the Lutaizi hydrological station upstream of the Bengbu Sluice.An indicator system was established,mainly including the interannual variation coefficient,interannual extreme ratio,percentage anomaly,non-uniformity coefficient,concentration degree,and concentration period.On this basis,an in-depth analysis was conducted on the interannual and intra-annual runoff variation trends in this river reach.The annual runoff upstream of the Bengbu Sluice showed an overall slight decreasing trend,while interannual fluctuations were pronounced,with extremely wet and extremely dry years occurring frequently.The intra-annual distribution of runoff tended to become more uniform,with an increasing proportion of runoff during the non-flood season.The concentration period was delayed by approximately 1 day every 23 years,whereas the runoff center of gravity remained relatively stable.The paper unveiled a shift in the streamflow regime from a pattern characterized by"high concentration during flood seasons"toward one marked by"more uniform intra-annual distribution".It also identified the delayed occurrence of peak flow concentration as a key phenomenon.The paper provides a scientific basis for the timely regulation of water storage and discharge at the Bengbu Sluice,optimized water resource allocation,and improved flood and drought risk management.