Laboratory experiments have been conducted in an effort to elucidate the details of the dissolved oxygen transfer mechanism at the sediment-water interface. Near-bed liquid turbulence and dissolved oxygen concentrations were measured for a range of Reynolds numbers from 2700 to 10,600 over a smooth bed. The results show that the shear stress velocity controls the dissolved oxygen diffusive layer thickness and therefore the local mass transfer coefficient at the sediment-water interface. From a dynamic point of view the results suggest the possibility that streamwise vortices control the interfacial dissolved oxygen transfer process. The research results will provide an opportunity to validate the existing conceptual models as well as enhance the development of new models that can improve our ability to predict dissolved oxygen and transport related parameters in lakes, reservoirs, coastal waters, and rivers. ¿ 1998 American Geophysical Union