Monitoring of Occurrence and Patterns of Toxic Metals in Mangrove Forests from the Oman Sea, Iran

Abstract

AbstractConcentrations of selected toxic metals were investigated in roots, stems, leaves and sediments from mangrove forests situated along the coast of the Oman Sea, Iran). The highest concentration of lead (48.86 μg/g dw) was measured in sediments, while the lowest concentration of lead was measured in mangrove leaves (0.94 μg/g dw). Calculated bioconcentration factors showed that all plant tissues were able to uptake copper from the sediments, making them suitable biological indicators for this metal. Similarly, the roots were found a suitable indicator for nickel and lead, while leaves and stems were better indicators for zinc contamination. Pollution indices showed that the sediments of mangrove forests along the coast of the Oman Sea were in the low ecological risk category (risk index < 150), and that all investigated sites were in the category of low to moderate pollution (pollution load index: 1.5-0.11), with a 21% probability of biological toxicity.

Keywords: Mangrove ecosystem, Heavy metals, geochemical indicators, bioavailability, Iran