Among coastal systems, coral reefs are thought to be especially susceptible to the amount of
UO 126 provided by anthropogenic activities (Smith and Buddemeier, 1992). In Bermuda, Castle Harbour's history of dredging and landfilling has been linked to increase leaching of contaminants into water, sediment, and marine tissue samples. Results from this study expand the environmental assessment of impacts from landfill leaching on the marine environmental by quantitatively demonstrating elevated metal uptake in corals growing in CH. Relative to the JSB coral, CH coral Pb, Zn, Mn and Hg concentrations were elevated, in concert with previous studies reporting elevated trace metals in sediment and water samples near the landfill. The CH record does not reveal a long-term trend. Instead, coral metal variability appears to be dominated by export of contaminants triggered by periodic input. Elevated contaminants in the surrounding
sediment suggest that resuspension is an important transport medium for transferring heavy metals to corals, with increased winds accompanied by higher coral variability at CH. Coupled with wind-induced resuspension, changes in sea level can enhance export and percolation of contaminants emanating from the landfill. The interplay of natural processes with land-based human activities is critical to evaluating the potential environmental impact of near shore contamination. The temporal and spatial comparisons between the CH and JSB coral records highlight the need to understand these combined effects and their impacts on coral record interpretation and ultimately coral health.
