A study on the heavy metals accumulation in sediment, leaf and root of Avicennia marina in Khuzestan province

Clean-up of ecosystems from heavy metals are essential, because heavy metals are not biodegradable. This study was carried out to investigate the mangrove role in accumulation or sequestration of heavy metals (Cu, Pb, Ni, Cd and Zn) from their surrounding environment. For this purpose, samples of sediment and mangrove roots and leaves were taken from Mangrove habitats in Bandar Imam Khomeini during winter. Samples of plant tissue were digested in HNO3 and H2O2(5:1) and sediment samples were digested in HNO3 and HClO4 (4:1) and their metals content was measured using atomic absorption spectrophotometry. Mean of copper concentrations in the sediment, root and leaf of different stations was 29.06, 11.3 and 6.36 μg/g, Pb: 23.68, 11.87 and 9.55 μg/g, Ni: 97.49, 7.35 and 5.01 μg/g, Cd: 5.62, 3.27 and 2.64 μg/g and Zn: 79.97, 32.07 and 18.86 respectively. Mean of heavy metals in area sediment were smaller than world sediment and crust. Also, calculation of marine pollution index was revealed that there are most of heavy metals in mangrove habitat 1.