Analysis of Spatiotemporal Evolution Characteristics of Flood Season Precipitation in Dianchi Lake Basin in the Past 50 Years
Based on the precipitation of the Dianchi Lake Basin during the flood season(May-October)from 1970 to 2020,this paper used geographic information technology,Mann-Kendall rank test,wavelet analysis and other methods to analyze the precipita-tion in the Dianchi Lake Basin during the flood season in the past 50 years,focusing on the trend,periodicity and concentration of interannual changes,concentration period,precipitation center and frequency of drought and flood evolution.The results show that,(1)in the past 50 years,the overall trend of flood precipitation is decreasing,with an increase in precipitation in the cen-tral region and a decrease in precipitation in the upper reaches of the Panlong River above the Songhua Dam Reservoir and the southern region;(2)There is a 31-year main cycle of interannual variation in flood precipitation,with a higher concentration of precipitation in the central main city than in the southern region;(3)The center of precipitation in the flood season generally shifts to the east and south,and the moving trend is significant;(4)Droughts and floods are frequent in the Dianchi basin,espe-cially in the upper and middle reaches of the Panlong River,which is a drought and flood prone area.This study could provide references to the flood and drought disaster prevention and water resources management in Dianchi Lake Basin.
Dianchi basinprecipitation of flood seasonconcentrationconcentration periodprecipitation center,drought and flood characteristics
万方数据
维普
