Temporal and spatial fluctuations of some heavy metals and silica in Tigris River water, downstream of Belad city, Iraq

This study was designed to assess the concentrations of six elements of zinc, cadmium, lead, nickel, aluminum, and total silica (SiO2) in Tigris River water downstream of Belad city and evaluate their temporal and spatial fluctuations. For this purpose, water samples were collected monthly, and four sampling sites were chosen and sampled during 2022. According to the results, the average concentrations of all metals in the water were within the permissible range by Iraqi river standards. Only aluminum slightly crossed the allowed levels during the study. In addition, the values of metals varied spatially and increased longitudinally. Generally, the concentrations of metals in the Tigris before Baghdad s Province entrance were parallel with many global rivers and increased steadily toward the downstream. Elevated Al concentrations are discussed regarding the river region s features and the sedimentation method.