Detailed Reference Information

Deep burrowing arthropods (Callianassa, Alpheus, and Upogebia) are prevalent vertical advectors of sediment throughout the shallow marine bays, lagoons and the reef-tract of South Florida.Their thumb-sized open burrow complexes commonly extend more than a meter into the subsurface.During burrow excavation and feeding, these crustaceans expel suspension-sized sediment to the depositional interface.Expelled sediment is overwhelmingly less than 175 mu m in settling diameter and represents grains swept up and out of the burrow by currents generated by the shrimp.Expelled sediment may be the finer-grained sediment from the original substrate in the case of deposit feeders or waste from suspension trapping during filter feeding.Large storms and hurricanes erode, resuspend and transport surficial sediments that infill open burrow complexes.Storm infilling from the surface is with a mixture of traction-bedload-sized grains and mud.Burrow excavation and feeding effectively transports deeply buried (> 1 meter) sediments, including particulate and surface adsorbed pollutants, to the depositional interface while storm infilling transports surficial sediment deep into the subsurface.Initial calibration of rates of burrow excavation and infilling using super(210)Pb geochronologies in Biscayne Bay, demonstrate vertical particle advection rates sufficiently fast to recycle 15-25% of the upper 1 to 1.5 m of deposit over 100 year time scales.Deep burrowing arthropods are present throughout Biscayne Bay, the reef tract and the more normal marine portions of Florida Bay.Vertical advection of particles by their burrowing and feeding behavior coupled with storm infilling of their burrows represents a major pathway for large-scale particle and pollutant transport.