estimation of some trace metals in water, sediments and two species of aquatic plants in the al-garaf river at al-rafa district- southern iraq

The current study was conducted to determines the concentration of four trace metals (cd, pb, cu and fe) in water (dissolved and particulate) phase, sediment (exchangeable and residual) and two species of aquatic plants phragmites australis and ceratophyllum demersium in al-garaf river of al-rafa district in south of iraq. the samples of the study were collected during the autumn and winter in 2018-2019 from three stations within al-rafa district. an atomic absorption spectrophotometer was used to measure the trace metals. the results showed that the concentrations in dissolved phase were (0.20, 0.60, 0.12 and 158.11) μg/l, while their concentrations in particulate phase were (14.34, 46.73, 17.76 and 2200.74) μg/g dry weight respective. for sediment, the mean concentrations of these metals in the exchangeable and residual phase were as follows (5.08, 0.035) (17.29, 2.71) (11.87, 13.23) and (622.18, 2366.02) μg/g dry weight. higher concentrations of the present study were observed in ceratophyllum demersum more than their concentration in phragmites australis. the current study concluded that the concentrations of studied metals in particulate phase were greater than their concentrations in sediment and also higher than their concentrations in the two plants.