ACCUMULATION OF HEAVY METALS (Pb, Cd, Hg) IN CORAL Acropora aspera AT POMALAA WATERS SOUTHEAST SULAWESI

Corals are one of the organisms that are sensitive to physical and chemical changes in the marine environment. Coral reefs in Pomalaa waters are starting to be threatened because of the nickel mining. This study aims to examine the water quality of coral reefs, and the level of accumulation of heavy metals (Pb, Cd, and Hg) in the waters and on coral (Acropora aspera) in Pomalaa waters. Samples were taken at 4 stations with the parameters measured were temperature, dissolved oxygen, pH, salinity, water clarity, current velocity, nitrate and phosphate. Seawater samples at each station were taken using a 500 ml sample bottle and 5 ml of HNO3 was added. Coral samples were taken at a depth of 5-10 m at 3-5 cm then prepared and analyzed using Atomic Absorption Spectrometer Method. The results showed that the heavy metals concentrations in water and coral had different concentrations. Accumulation of heavy metals in water samples exceeds the threshold for sea water quality standards for marine biota. Accumulation of heavy metals in coral skeletons has different concentrations for each type of metal. Concentration of Pb in corals ranged from 1.20 to 28.40 mg/kg. Concentrations Cd from 12.06 to 18.53 mg/kg, while the Hg concentration from 0.03 to 1.70 mg/kg. Concentration of metals accumulated in corals is greater than in seawater. Corals have a high tendency to accumulate metals, so they can be used as bioindicators to see the level of pollution in marine waters.