High wind speeds prevent formation of a distinct bacterioneuston community in the sea-surface microlayer. Issue 5 (22nd March 2017)

• Record Type: Journal Article
• Authors: Rahlff, Janina; Stolle, Christian; Giebel, Helge-Ansgar; Brinkhoff, Thorsten; Ribas-Ribas, Mariana; Hodapp, Dorothee; Wurl, Oliver
• Is Part Of: FEMS microbiology ecology. Volume 93:Issue 5(2017:May)
• Publication Date: 2017-03-22
• Subjects: air–sea interface -- bacterioneuston -- enrichment factor -- wind-wave tunnel -- Baltic Sea, pCO2; Microbial ecology -- Periodicals; Microbiology -- Periodicals; 579.17
• DOI: 10.1093/femsec/fix041
• Languages: English
• ISSNs: 0168-6496

Abstract

Abstract: The sea-surface microlayer (SML) at the boundary between atmosphere and hydrosphere represents a demanding habitat for bacteria. Wind speed is a crucial but poorly studied factor for its physical integrity. Increasing atmospheric burden of CO2, as suggested for future climate scenarios, may particularly act on this habitat at the air–sea interface. We investigated the effect of increasing wind speeds and different p CO2 levels on SML microbial communities in a wind-wave tunnel, which offered the advantage of low spatial and temporal variability. We found that enrichment of bacteria in the SML occurred solely at a U10 wind speed of ≤5.6 m s −1 in the tunnel and ≤4.1 m s −1 in the Baltic Sea. High p CO2 levels further intensified the bacterial enrichment in the SML during low wind speed. In addition, low wind speed and p CO2 induced the formation of a distinctive bacterial community as revealed by 16S rRNA gene fingerprints and influenced the presence or absence of individual taxonomic units within the SML. We conclude that physical stability of the SML below a system-specific wind speed threshold induces specific bacterial communities in the SML entailing strong implications for ecosystem functioning by wind-driven impacts on habitat properties, gas exchange and matter cycling processes. Abstract : Bacteria inhabiting the sea-surface microlayer are enriched and prone to community changes in response to wind speed conditions and p CO2 levels.