Assessment of Cd, Ca, Zn, Cr, Al concentrations in water, sediment and tissues of mangrove forest, Avicennia marina from Qeshm Island, Persian Gulf

Abstract

In this study, the heavy metals pollution in water, sediments and different tissues (root, stem and leaf) of mangrove forest, <em>Avicennia marina,</em> from Qeshm Island, Persian Gulf was investigated. Sampling was performed in 10 stations along the Qeshm Island and Khmir Port located in Hormozgan province. The average concentration of metals was measured using the ICP-AES. The average concentration of Cd, Ca, Zn, Cr, Al in water samples was: 0.015 µg.g^-1, 66.4 µg.g^-1, 0.014 µg.g^-1, 0.01 µg.g^-1and 62.15 µg.g^-1, respectively. The average concentration of Cd, Ca, Zn, Cr, Al in leaf of <em>A. marina </em>was: 0.11, 4954, 12, 1.07 and 721 µg/g; in stem tissues it was 0.07, 10.04, 1.16 and 648.54 µg/g, and in the root tissues it was 0.24, 18234, 14.4, 7.24 and 1982 µg/g, respectively. Also, the average concentration of metals (µg.g^-1) in sediment samples was 1.04 for Cd, 48.18 for Zn, 79.61 for Cr and 27578 for Al. The decreasing trend of metals concentration in water, sediment and tissues of <em>A. marina</em> in all stations was observed as Ca > Al > Cd > Zn > Cr. There were significant differences in metals concentration between tissues of <em>A. marina</em> (P<0.05), with the highest level absorbed in root, followed by leaf and stem. High positive correlation between heavy metal concentration in the sediments and root showed that root tissue of <em>A. marina</em> which accumulates metals and transport them to leaves can be an appropriate biomarker for detection of heavy metals in marine coast areas.