Correlation Analysis between Runoff and Meteorological Elements in the Upper Reaches of Shiyang River
Meteorological factors are important factors driving the evolution of runoff.Cross-wavelet method was used to analyze the resonance cycle law between runoff and precipitation,maximum temperature and minimum temperature of four typical tributaries in the upper reaches of Shiyang River,which reveals the degree changes and anomalies of correlation in different time domains and frequency domains,supplementing the existing correlation research.The results show that the runoff at Xidaxihe Reservoir station and Dajingxia Reservoir station has an increasing trend while the runoff at Nanying Reservoir station and Gulang station decreases.The cycle pattern and correlation between the runoff and precipitation are the most significant,followed by the maximum temperature and the minimum temperature,and the resonance period ranges from 2 a to 8 a.The analysis shows that this method plays an important role in guiding the exploration of the mutation of meteorological factors,the correlation of hydrometeorological elements and their time-frequency changes.When implementing targeted water replenishment in the Shiyang River Basin,priority should be given to artificial rainfall from the precipitation link.