Temporal and spatial variation of some heavy metals in limnology environment

The current study is aimed at investigating heavy metals (e.g., Cd, Co, Fe, and Pb) concentrations in the samples’ of water from Euphrates River/Iraq. These samples were assessed to determine the level of contaminations depending on the water quality indices (i.e., heavy metal pollution (HPI) and heavy metal evaluation index (HEI)) to estimate the water pollution. These sites were extended from the Hindiya dam to Mishkab Regulator. The period of sampling was from January to December of 2016. The results showed that Pb⪆Fe⪆Cd⪆Co heavy metals were seen in a level that is higher than the recommended level for drinking water and aquatic life guidelines. The concentration of heavy metals was seen to vary across seasons, with the highest levels for each of cadmium in spring, lead in Autumn, cobalt in winter, and Iron in summer. The spatial variations reported a variability between the sites, in which the highest values of cadmium and lead were seen at sites 13 and eight, respectively. The values of cobalt and iron were gradually increased from the first site to the 14th site. The temporally variations of The HPI for heavy metals were classified as low in winter and high in other seasons, while the spatial variations were classified as high in sites (one, four, six, eight, ten, 12 and 13) due to the fact that they were noticed over the critical index of pollution level at (100). The spatial variations of HEI for lead (Pb) were classified as high in all sites except sites one and 11.