Different runoff patterns determined by stable isotopes and multi-time runoff responses to precipitation in a seasonal frost area: a case study in the Songhua River basin, northeast China

Abstract

AbstractRunoff patterns are crucial to determine the hydrological response to climate change, especially in a seasonal frost area. In this study, multi-time runoff responses to meteoric precipitation for the period from July 2014 to June 2016 and the period from 1955 to 2010 were obtained to identify different runoff patterns in the Songhua River basin, northeast China, based on six stations. Two distinctly different runoff responses are exhibited: a periodic one in response to precipitation in the Nen River and a constant one in the Second Songhua River under different scales. Stable isotopes in the plain with diverse characteristics also supported these runoff patterns. What is more, gradual runoff relatively less sensitive to precipitation in the Second Songhua Rive was attributed to upstream dam constructions. Furthermore, the Second Songhua River contributes more water to the main stream during January to March at the seasonal scale and in the 2000s at the annual scale, with low precipitation during those periods. This study could have implications for water management in the Songhua River basin.