Analysis of Spatial Variability of River Bottom Sediment Pollution with Heavy Metals and Assessment of Potential Ecological Hazard for the Warta River, Poland

Pollution of river bottom sediments with heavy metals (HMs) has emerged as a main environmental issue related to intensive anthropopressure on the water environment. In this context, risk harmful effects HMs presence in Warta River, third longest Poland, been assessed. The concentrations Cr, Ni, Cu, Zn, Cd, and Pb collected at 24 sample collection stations along whole length have measured analyzed. Moreover, GIS environment, method predicting variation length, not particular sites, proposed. Analysis River sediment pollution terms indices: Geoaccumulation Index (Igeo), Enrichment Factor (EF), Load (PLI), Metal (MPI), proved that, 2016, was heavier than 2017. Assessment potential toxic accumulated sediments, made basis Threshold Effect Concentration (TEC), Midpoint (MEC), Probable (PEC) values, Toxic Risk (TRI), shown that ecological hazard 2017 much lower. Cluster analysis revealed two groups which showed similar chemical properties. Changes classification into analyzed over period subsequent years indicated impact could their point sources urbanized areas fluvial process.