Temperature changes in the tidal excursion front and surface sediment of a subtropical mudflat in autumn

Temperature changes in sediment and the inundating water of a subtropical mudflat were determined using a series of data-loggers to monitor the temperature on fine days around the equinox at Lota, Queensland, Australia. On fine days the temperature of the forward shallow (ca. 5 cm) section of an incoming tide is up to 8 °C higher than that of the body of water from which it originates. Stationary data-loggers in the sediment indicate that during the day heat exchange occurred between the sediment and inundating waters, the sediment temperatures dropping from up to 10 °C higher than channel waters to temperatures approaching that of channel water in as little as 30 min following inundation. The implications for intertidal nekton and benthos are discussed.