Effects of Macrofaunal Bioturbation on Dynamics of Oxygen and Nutrients in Tidal Sediments of the West Coast of Korea

Abstract

Macrofaunal bioturbation and its effects in relation to increasing the sediment-water interface, oxygen diffusion from the interface into ambient sediments, and the dynamics of oxygen and nutrients within sediments were investigated on the tidal flats of the west coast of Korea. The present study was carried out to better understand the geochemical implications of the bioturbation in tidal sediments by setting out the following objectives; 1) quantification of the increase in the sediment- water interface caused by the biogenic structure of the macrofaunal community and its variation with respect to physical conditions in the tidal habitats, 2) analysis of bioturbation effects on oxygen diffusion from the sediment-water interface, and on the increase in oxic sediment volume within the tidal sediments, 3) introduction of the burrow architecture of Laomedia astacina, an ecologically unknown species, and continuous in situ measurements of oxygen concentration in its burrows, and 4) evaluation of nutrient fluxes through both tidal surfaces and Laomedia burrows.