A NONLINEAR TIME-SERIES MODEL FOR SPRING FLOW - AN EXAMPLE FROM SHANXI PROVINCE, CHINA

A nonlinear time series model is presented to describe the dynamics of ground water now. The procedures for model-establishing and parameter estimation are discussed, The proposed nonlinear model uses a thresho ld parameter that relates different precipitation processes, and a lag parameter that relates the time lag between precipitation events and observed increasing spring flow. This model is then applied to the pre diction of time-dependent now of the Longzichi Spring, Shanxi Province , northwest China. The results in this analysis show that the proposed approach can accurately describe the complicated nonlinear time serie s and the discharge regime of the Longzichi Spring.