Screening of prevailing processes that drive surface water quality of running waters in a cultivated wetland region of Germany - A multivariate approach

► We used nonlinear PCA (Isomap) to analyze prevailing water quality processes in a cultivated German wetland region. ► Major impacts on water quality are peat degradation, mixing with mining drainage waters and groundwater exfiltration. ► Isomap proved a powerful tool for process analysis in complex wetland systems if possible occurring processes are known. ► To decrease negative impacts of SO4 input from brown coal mining, upstream wetland buffer capacities should be used. ► To reduce peat mineralization and groundwater exfiltration, water tables of peatlands and receiving waters should be raised.