Using aeration to probe the flow characteristics associated with long-term marine macrofouling growth and suppression

Abstract

It is well-established that hydrodynamics affect the settlement of biofouling organisms. Laboratory studies have demonstrated a connection between larval attachment rates and the prevalence of time windows that satisfy certain instantaneous flow conditions. However, it is unclear whether a link exists between short-term hydrodynamics and long-term macrofouling survival and growth, or if it is applicable at an ecosystem-wide level. This study used single bubble stream aeration in field and laboratory experiments to find critical flow characteristics that correlate to long-term, multi-species fouling prevention. The research was accomplished by combining PIV-derived flow statistics with fouling severity measured over seven weeks in the field. Flows with a decreasing proportion of time windows defined by a flow speed < 15.1 mm s⁻¹ for longer than 0.03 s correlated to decreased biofouling growth and survival. These results provide a potential framework for studying and comparing flow fields that successfully inhibit biofouling growth.

Keywords:

• Aeration
• flow characteristics
• bubble
• macrofouling
• grooming

Acknowledgements

The authors acknowledge J. Rekos and M. Boyer for their assistance with the field campaign, and Dr F. Brasz for his assistance in PIV data collection.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by the Office of Naval Research under Grant No. N00014-16-1-3000. M.M acknowledges support by the National Science Foundation Graduate Research Fellowship Program under Grant No. DGE-1247312 and an internship provided through the Graduate Research Internship Program (GRIP). L.D acknowledges support by the National Science Foundation Graduate Research Fellowship Program under Grant No. DGE-1840990. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of the funding agencies.