Characterization of temporal and stratigraphic changes in texture, composition, nutrients and organic content of bottom sediments in the Mayaguez Bay, Puerto Rico

Five bottom sediment cores were collected in three areas of different sedimentation along the Mayaguez Bay. The cores were sub-sampled at different intervals from top to bottom. Mineralogy, texture, composition, and nutrient levels were measured and identified for each sub-sample collected from the cores. The sediment core data was compared to sediment trap data from the same sites to determine any differences, in texture, composition, and mineralogy. The mineralogy of the bottom and sediment trap material was virtually the same. The sediment trap material represents the suspended and dissolved sediments being deposited in the near-shore sites along the bay. Very high nutrient concentrations were detected at various sites along the bay. The results suggest that the Mayaguez Bay waters are not nitrogen or phosphorus limited. The abundance of nutrients allows for algae to successfully compete against the corals for hard substrate space, severely damaging the coral reef environment.