SPATIO-TEMPORAL VARIABILITY OF WATER POLLUTION IN THE WATERSHED OF WADI ECHAREF, SEDRATA, ALGERIA

Abstract

In order to monitor the spatio-temporal variability of water pollution in Wadi Echaref water shed, seven physico-chemical parameters are measured repeatedly over time (05 campaigns) in six selected sampling stations along this hydro system. The latter is subject to a pollution generated by discharges of domestic and industrial wastewater from two cities of Sédrata and M’daourouch. It receives daily more than 5313 m3/day of waste water, 5000 of which are treated by the STEP (waste water treatment plant) of Sédrata and more than 313 m3 are discharged directly without any prior treatment. In order to study the temporal stability of the spatial structure and measure the date station interaction in the 5 mesological tables obtained, we used partial triadic analysis. The study of the obtained results’ temporal structure reveals the existence of a common structure among the different dates that reflect a downstream upstream type of spatial expression described by the variables that characterize the pollution. The stations (S1, S2, S3 and S4) located downstream the domestic and industrial discharges of the cities of Sédrata and M’Daourouch, are still opposed to other stations, highlighting that these stations remain polluted during the study period, as evidenced by the concentration of Nickel, Silver and Cobalt.