Meeting Abstract

88.1  Monday, Jan. 6 13:30  Effects of temperature on ventilation patterns in polychaete burrows MURPHY, E.A.K.*; REIDENBACH, M.A.; Univ. of Virginia; Univ. of Virginia eam6vf@virginia.edu

Burrowing organisms living in temperate intertidal zones are subject to extreme temperature fluctuations on daily to seasonal timescales. Many of these organisms build permanent or semi-permanent burrows that they irrigate with overlying water. This activity expands the sediment-water interface, enhancing exchange of solutes between porewater and surface water, and altering sediment chemistry. We investigated 1) the temperature variations experienced by organisms at three depths between 3 and 25 cm in intertidal muddy sediment on Virginia’s Delmarva peninsula and 2) the effects of temperature variations on ventilation patterns in irrigated burrows. HOBO temperature loggers were buried within intertidal mudflats to examine temperatures experienced by burrowing organisms at different depths throughout multiple tidal cycles. To examine how temperature affects the ventilation of irrigated burrows we used Neanthes succinea, a common polychaete, as a model organism. This species builds U-shaped burrows and irrigates the burrows by undulating its body. A planar optode was used within a mesocosm composed of natural sediment to measure oxygen levels in burrows at three temperatures between 6 and 36 ° C that correspond to the range of temperatures experienced seasonally. We found that oxygen levels in natural burrows follow a distinct pattern with higher temperatures corresponding to increased frequency of ventilation and lower oxygen levels in the burrow and lower temperatures corresponding to decreased frequency of ventilation and increased oxygen levels.