Send to

Choose Destination
FEMS Microbiol Ecol. 2014 Sep;89(3):670-8. doi: 10.1111/1574-6941.12368. Epub 2014 Jul 2.

Intertidal epilithic bacteria diversity changes along a naturally occurring carbon dioxide and pH gradient.

Author information

Marine Biological Association of the United Kingdom, The Laboratory, Citadel Hill, Plymouth, UK.


Intertidal epilithic bacteria communities are important components of coastal ecosystems, yet few studies have assessed their diversity and how it may be affected by changing environmental parameters. Submarine CO2 seeps produce localised areas of CO2-enriched seawater with reduced pH levels. We utilised the seawater pH/CO2 gradient at Levante Bay (Italy) to test the hypothesis that epilithic bacteria communities are modified by exposure to seawater with the varying chemical parameters. Biofilms were sampled from three sites exposed to seawater with different pH/CO2 levels and diversity determined using high-throughput sequencing of 16S rRNA genes. Seawater pCO2 concentrations were increased from ambient at site 1 to 621 μatm at site 2 and 1654 μatm site 3, similar to the predicated future oceans beyond 2050 and 2150, respectively. Alpha diversity of total bacteria communities and Cyanobacteria communities was significantly different between sites (anova P < 0.05). Comparison between sites showed that bacteria communities and Cyanobacteria communities were significantly different (anosim P < 0.01; permanova P < 0.01). Proteobacteria, Bacteroidetes and Cyanobacteria dominated all communities; however, there were differences between sites in the relative abundance of specific orders. This study provides the most detailed assessment of intertidal epilithic bacteria diversity and shows that diversity is significantly different along a seawater pH/CO2 gradient. This information supports the evaluation of the impacts of future ocean acidification on coastal marine ecosystems.


bacteria; biofilms; carbon dioxide; diversity; epilithic; pH

[Indexed for MEDLINE]
Free full text

Supplemental Content

Full text links

Icon for Silverchair Information Systems Icon for Wiley
Loading ...
Support Center