Environmental study of water quality and some heavy metals in water, sediment and aquatic macrophytas in lotic ecosystem, Iraq

摘要

This study was respect to detect possible environmental effects on the eastern Euphrates drainage from the Abo-Garak to south of Kifil city in Babylon province. Five sites were selected along the study area and Omit it during October 2013 to August 2014. Physical and chemical properties are measured (air and water temperature , pH , electrical conductivity , salinity, TDS ,TSS , BOD5, dissolved oxygen , Alkalinity , Total Hardness , calcium , magnesium ) and nutrients (nitrite , nitrate , reactive phosphate) as well as . The average of the studied heavy metals Fe , Cd , Pb and Cu the dissolved phase of water were 113.89 , 6.35 , 1.5 and 0.8μg /l for Fe , Cd , Pb and Cu , respectively .Heavy metals concentrations in the particulate form were 291.83, 9.39, 3.07 and 12.15 μg/g dry weight for Fe , Cd , Pb and Cu respectively. In the sediments, the concentrations of these heavy metals in the exchangeable phase were 318.66, 12.91, 6.27 and 13.23μg/g for Fe , Cd , Pb and Cu , respectively. While in the residual phase were 461.53, 5.29, 8.62 and 27.07 μg/g for Fe , Cd , Pb and Cu , respectively . The results revealed that the concentrations of heavy metals in water for the particulate phase were higher than in the dissolved phase , while in sediment, their concentrations in the residual phase were higher than their concentrations in the exchangeable phase except for Cd which was in the exchangeable phase higher than in the residual phase. The concentration and distribution of heavy metals in macrophytes Ceratophyllum demersum were (923.63 , 462.34 , 740.45 and 90.59)μg/g dry weight for Fe , Cd , Pb and Cu , respectively . While , (728.57, 162.17 , 244.13 and 118.87) μg/g dry weight for Fe , Cd , Pb and Cu , respectively. for Fe , Cd , Pb and Cu in Hydrilla verticillata .The study area was very hard water and high BOD5. The nutrients showed clear seasonal variation in their concentration.