Uptake of Ag, Co and Ni by the Organs of Typha domingensis (Pers.) Poir. ex Steud. in Lake Burullus and Their Potential Use As Contamination Indicators

摘要

The concentrations of Ag, Co and Ni in the sediments and the different organs of Typha domingensis from Lake Burullus, Egypt, were investigated monthly from February to September 2010 to evaluate the aquatic environment quality of the lake and to test the suitability of these organs for bio-indicating of sediment metals. The sediment heavy metals were found to decrease in the order of Ni > Co > Ag. The sediment contents of Ag were about 45 times above the worldwide range. On the other hand, Co concentrations were below the reference ranges of United States and Chinese soils. The heavy metals bioaccumulation decreased according to the order of rhizome > root > leaf for Ag; and root > rhizome > leaf for Co and Ni. It was found also that, T. domingensis had no significant differences in heavy metals concentrations over time. The transfer factors of Ag, Co and Ni from sediment to below-ground organs were smaller than one. Co had the maximum transport from below-ground to above-ground organs, while Ag had the minimum. There was a significant linear correlation between the concentration of Ag in root of T. domingensis and that in sediment. This result suggested that T. domingensis can be regarded as bio-indicator for Ag pollution of Lake Burullus.