Human Impacts on Estuarine Sedimentary Processes

Increasing pressures from human-induced activities are causing habitat loss and degradation, fisheries declines, and overall reductions in estuarine health and productivity. Associated physical alterations, such as dredging, damming, and bulkheading, change the natural flow of fresh water to estuaries, dramatically affecting water quality. Toxic substances and excess nutrients contribute to fish diseases, algal blooms, and low dissolved oxygen and can pose a threat to the health of humans and estuarine wildlife.

Estuarine sediments play a critical role in the understanding of how humans have impacted natural processes. In many coastal areas, the estuaries have been affected by human activity for hundreds of years, making it difficult to establish “natural” baselines of water and sediment quality standards. By evaluating sediment cores from estuaries, we can look back in time to ascertain such baselines, but also see how water and sediment quality have changed over time.

Florida has the fastest growing coastal population in the United States, with over a dozen coastal counties expecting growths of their populations exceeding 50% over the next ten years. These estuaries currently are showing the impacts of human activities within their respective watersheds. Estuarine geological research at UF is focused on understanding how sedimentary processes have been modified by human activities. Active projects include:

· Late Holocene to Modern Sedimentary Processes in the Loxahatchee River Estuary, Palm Beach County

· The Impact of Bioturbation on Nutrient Fluxes, Lower St. John’s River Estuary

· Historical Changes in Nutrient Loads and Sedimentary Processes, Lower St. John’s River Estuary

· Late Holocene Sedimentary Processes and Groundwater Fluxes, Indian River Lagoon

· The Impact of Varying Sedimentation Rates on Seagrass Bed Viability