Figure 3 and Table 4 show the abrupt change point of runoff in the MRYR and nine sub-basins from 1960 to 2020. Among them, abrupt change points in FR and QR are significantly earlier (before 1975) than the rest. Abrupt change points can be detected around 1998 (HF, YR, and BL), and 1989 (KY and JR). Runoff in WD and YL experienced significant variation after the 1980s (1981 and 1985, respectively). For each sub-basin, the historical records before the abrupt change point were used as the base period (Period I), and the rest was used as the runoff in the change period (Period II) for follow-up research.