Abstract
Mixing inside free floating mesocosms (marine enclosures) is essential to reproduce the marine surface environment. Thus, two devices, a disc and a pump were developed and deployed into a reduced scale (about 1/10) mesocosm. The disc device is comprised of a wooden seesaw, a float and five perforated discs. The pump device is comprised of the same seesaw and float and a plastic pipe with a check valve. Both devices transfer energy into the mesocosm in response to the movement of the float outside the mesocosm. These two devices provided turbulent mixing and/or upward vertical advection, resulting in stronger mixing than in the control case (with no device). On the other hand, when waves were strong, enough mixing was occurred in the control case. Optimal design of mesocosms in terms of selection and/or combination of such devices (including the do nothing case) depends highly on the strength of wave fields.
