Bioavailability of Pb and Cu in Sediments of Vegetated Seagrass, Enhalus acoroides, from Spermonde Islands, Makassar, South Sulawesi, Indonesia

摘要

Seagrass might impact metal bioavailability in sediments with physiological processes that occur at the root and rhizome. Seagrass growth may increase bioavailability due to oxygen transport from leaves to the root systems. This study aims to analyzethe concentrations of bioavailable Pb and Cu in sediments with and without seagrass. This study was done at two sites in Spermonde Islands, South Sulawesi, Indonesia. All metals analysis and sediment parameters were conducted on dry, <63 urn grain size sediment samples. Metal speciation in sediment was determined using the Community Bureau of Reference (BCR) three steps sequential that extract exchangeable and acid soluble fraction, reducible and oxidisable fraction.The average concentrations of bioavailable fraction of Pb and Cu (fraction 1) was higher in vegetated sediments associated with Enhalus acoroides than in unvegetated sediments. Higher concentration of Cu infraction 1 was also associated with higher concentration in Enhalus roots. This indicates that the presence of seagrass may increase the bioavailability of metals in sediments. Increased metal bioavailability in vegetated sediment will imply increase toxicity.