Trend analysis of runoff and base-flow at Lan Village Station on the upper Fen River
In order to reveal the change rule of runoff and base-flow in the Fen River basin,based on the runoff se-quence data from 1956 to 2020 at Lan Village Station in the upper Fen River,the daily runoff was divided into direct runoff and base-flow by using digital filtering method,runoff and base-flow were discriminated by the M-K test,and the long range correlation analyses of the annual runoff and annual base-flow were carried out by using the rescaled-pole(R/S)a-nalysis method.The results show that:The base flow index(BFI)of Lan Village Station showed a trend of decreasing and then increasing between years;the change process of base flow depth and runoff depth showed a significant decreasing trend,and the mutation point of runoff depth appeared in 1974,and the mutation point of base flow depth was in 1972;the time se-ries of annual runoff depth and base flow depth both showed a strong long term correlation,i.e.,there is a tendency of further decreasing in the future.
base-flow indexdigital filtering methodlong-range correlationLan Village Station
NETL
NSTL
万方数据
