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 flow. The procedures for model-establishing and parameter estimation are discussed. The proposed nonlinear model uses a threshold 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 prediction of time-dependent flow 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 series and the discharge regime of the Longzichi Spring.