Heavy Metal Accumulation in Seagrasses in Southeastern Florida

Seagrass beds are among the most ecologically important systems in the marine environment and comprise a large component of the diets of many marine organisms, which provides a pathway for contaminants in the seagrasses to enter the marine food web. In this study, three species of seagrasses, Thalassia testudinum, Halodule wrightii, and Syringodium filiforme, were collected monthly, for one year, in three regional locations in South Florida - Port of Miami, Card Sound region of Biscayne Bay Aquatic Preserve, and Florida Bay. These were analyzed for ten heavy metals using Atomic Absorption Spectroscopy. The metal concentrations varied significantly between the three locations, though each location had similar dominant metals (Cu, Fe, Mn, Zn). Significantly higher concentrations of heavy metals were found during the wet season, with the exception of Zn. Metals such as Fe, Mn, and Zn were found to be significantly higher in leaves with epiphytes.