Modeling Complex Concentration-Discharge Relationships with Generalized Additive Models

Abstract Concentration-discharge relationships in water chemical time series can provide important insights into sources, mobilization, and delivery of solutes particulates stream networks. The observed are often complex, including nonlinear hysteretic patterns reflecting seasonal, climatic, land management changes biogeochemical release hydrological transport to streams. Using standard single concentration-discharge ( c - q ) slopes obscure this wealth information. In study, we suggest a new approach using generalized additive models for evaluation complex low-frequency quality data (only monthly or biweekly observations). We used these estimate together with their uncertainty, evidence behaviors controls. estimated selection Swedish streams evaluated nonlinear, temporal structure as indicators changing biochemical drivers.