Oxygen transport in periodically ventilated polychaete burrows

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Burrowing organisms play a critical role in the functioning of marine sediments in coastal systems, in part due to their pumping of oxygenated water through the burrow. In cohesive sediments, oxygenated burrow water allows for the flux of oxygen across the burrow wall and into the sediment, where it is consumed. In this study, we quantified the burrow oxygenation patterns of the polychaete A. succinea. We determined that periodic ventilation of the burrow results in oscillations in the magnitude of the flux of oxygen across the burrow wall and in the oxygen concentration within the sediment near the burrow wall. The mean flux of oxygen across the burrow wall was 1.7± 0.3 x10^-8 µmol mm^-2 s^-1 (N = 4), and the mean oxygen penetration distance into the sediment at the burrow wall was 2.4±0.2 (N = 4). Additionally we investigated the effects of temperature on the oxygen dynamics in the burrow. The frequency of burrow oxygenation by its polychaete inhabitant increases with increase in temperature, ranging from 1.7 ± 0.6 x10^-4 Hz at 6 °C to 10.6 ± 3.0 x10^-4 Hz at 33 °C (N = 4). The frequency of the oscillations in oxygen flux across the burrow walls also increased with temperature, following a pattern similar to the oxygenation frequency.