EVALUATING THE ROLE OF POOLS IN THE SEDIMENT DYNAMICS OF A NEW ENGLAND SALT MARSH

Saltmarsh pools, shallow, unvegetated depressions which remain filled with salt water throughout a tidal cycle, are a common feature of New England salt marshes. Multiple studies have noted an increase in the number and area of pools in recent decades, with different authors attributing these changes to a variety of potential mechanisms. In order to better understand the origin and evolution of pools, their role in the overall sediment dynamics of marsh platforms, and potential causes of changes in the extent of pools, we are studying sedimentation in multiple pools and the surrounding marsh platform of the Little River saltmarsh in Reid State Park, Maine. Little River Marsh was never ditched and has an abundance of pools with widely varying morphology and drainage connectivity. We are evaluating both short-term and long-term sedimentary processes by utilizing seasonally deployed sediment traps and turbidity loggers in addition to sediment cores recording decades of marsh accumulation. To better understand how sedimentation changes throughout the course of pool evolution we are targeting disconnected, connected, and actively revegetating pools, and will use observational and core data in addition to aerial imagery to evaluate changes in pool morphology over time. By comparing cores from the marsh platform with cores from current pools, we can explore changes in sedimentation over the course of pool lifespan. A better understanding of the evolution of marsh pools and their role in sedimentary processes within tidal marshes will help inform evaluations of marsh health and future sustainability.