Abstract: Heavy metals such as iron (Fe), manganese (Mn), zinc (Zn), copper
(Cu), nickel (Ni), cobalt (Co), lead (Pb) and cadmium (Cd) concentration range
were 13330–32500 ppm, 260–780 ppm, 32.7–158 ppm, 27.6–82.6 ppm, 15.6–46.8 ppm,
5.46–42.7 ppm, 3.48–14.7 ppm and 0.15–1.75 ppm reported respectively. At all
the sampling sites, the mean concentrations were found to follow the decreasing
orders: Fe > Mn > Zn > Cu > Ni > Co > Pb > Cd. ANOVA of
variation ratio and level of significance between study areas were 1%
significant except manganese (5%) and copper (not significant). Statistical
reports also showed 1% significant except cadmium (5%). Iron and zinc can be
considered as high level of contamination and a serious threat, copper was a
moderate to serious threat, nickel slight contamination and cadmium no
hazards.
Keywords: Mangroves, sediment, heavy metals, iron, copper, cadmium, lead, nickel
