Trend Analysis of Annual Runoff in Yong’an Creek Basin of Zhejiang

Abstract

Yong’an Creek is the source of the Lingjiang River, one of the eight major river systems in Zhejiang, and is of great significance to support the economic and social development of the Zhejiang region. Based on the runoff data of Baizhi’ao Hydrological Station from 1985 to 2020, this paper uses linear regression, Mann-Kendall method and Sen’s slope estimator to analyze the change trend of the annual runoff of Yong’an Creek, and diagnoses abrupt changes. The results show: The runoff in the Yong’an Creek basin has large interannual variability, and the linear regression and M-K trend test results show that the runoff in the Yongan River Basin has a downward trend. There is no real mutation point in the precipitation in the Yong’an Creek basin from 1985 to 2020. The results of Sen’s slope show that the rate of change of runoff is small. The results of the study will provide necessary guidance for sustainable water resources management and disaster risk reduction of the Yong’an Creek basin.