Seawater carbonate chemistry and bacterial diversity of intertidal bacterial biofilm communities

• Main Authors: Kerfahi, Dorsaf, Harvey, Ben P, Agostini, Sylvain, Kon, Koetsu, Huang, Ruiping, Adams, Jonathan M, Hall-Spencer, Jason M
• Format: Dataset
• Language: English
• Published: PANGAEA 2020
• Subjects: ACE richness; Alkalinity; total; Aragonite saturation state; Benthos; Bicarbonate ion; Calcite saturation state; Calculated using seacarb after Nisumaa et al. (2010); Carbon; inorganic; dissolved; Carbonate ion; Carbonate system computation flag; Carbon dioxide; Chao 1 richness; CO2 vent; Coast and continental shelf; Community composition and diversity; Entire community; EXP; Experiment; Field observation; Fugacity of carbon dioxide (water) at sea surface temperature (wet air); Group; LATITUDE; LONGITUDE; North Pacific; OA-ICC; Ocean Acidification International Coordination Centre; Oxygen; Partial pressure of carbon dioxide (water) at sea surface temperature (wet air); pH; Potentiometric; Potentiometric titration; Rocky-shore community; Salinity; Shannon Diversity Index; Shikine_Island; Simpson index of diversity; Site; Species richness; Temperate; Temperature; water; Type; Pacific; Ocean acidification
• Online Access: https://doi.pangaea.de/10.1594/PANGAEA.930400; https://doi.org/10.1594/PANGAEA.930400

The effects of ocean acidification on ecosystems remain poorly understood, because it is difficult to simulate the effects of elevated CO2 on entire marine communities. Natural systems enriched in CO2 are being used to help understand the long-term effects of ocean acidification in situ. Here, we compared biofilm bacterial communities on intertidal cobbles/boulders and bedrock along a seawater CO2 gradient off Japan. Samples sequenced for 16S rRNA showed differences in bacterial communities with different pCO2 and between habitat types. In both habitats, bacterial diversity increased in the acidified conditions. Differences in pCO2 were associated with differences in the relative abundance of the dominant phyla. However, despite the differences in community composition, there was no indication that these changes would be significant for nutrient cycling and ecosystem function. As well as direct effects of seawater chemistry on the biofilm, increased microalgal growth and decreased grazing may contribute to the shift in bacterial composition at high CO2, as documented by other studies. Thus, the effects of changes in bacterial community composition due to globally increasing pCO2 levels require further investigation to assess the implications for marine ecosystem function. However, the apparent lack of functional shifts in biofilms along the pCO2 gradient is a reassuring indicator of stability of their ecosystem functions in shallow ocean margins.