MEPS 550:121-134 (2016)  -  DOI: https://doi.org/10.3354/meps11727

Distribution and functional traits of polychaetes in a CO2 vent system: winners and losers among closely related species

M. C. Gambi1, L. Musco2,6,*, A. Giangrande3, F. Badalamenti2, F. Micheli4, K. J. Kroeker5

1Stazione Zoologica Anton Dohrn - Integrative Marine Ecology, Villa Dohrn-Benthic Ecology Center, 80077 Ischia, Napoli, Italy
2Laboratory of Marine Ecology - IAMC - CNR, 91014 Castellammare del Golfo, Italy
3University of Salento, DiSTeBA, 73100 Lecce, Italy
4Hopkins Marine Station, Stanford University, Pacific Grove, CA 93950, USA
5University of California at Santa Cruz, Santa Cruz, CA 95064, USA
6Present address: Stazione Zoologica Anton Dohrn, 80121 Napoli, Italy
*Corresponding author:

ABSTRACT: We report on fine taxonomic and functional analyses of polychaetes associated with rocky reefs along a gradient of ocean acidification (OA) at the volcanic CO2 vent system off the Castello Aragonese (Ischia Island, Italy). Percent cover of algae and sessile invertebrates (a determinant of polychaete distribution) was classified into functional groups to disentangle the direct effects of low pH on polychaete abundance from the indirect effects of pH on habitat and other species associations. A total of 6459 polychaete specimens belonging to 83 taxa were collected. Polychaete species richness and abundance dramatically dropped under the extreme low pH conditions due to the disappearance of both calcifying and non-calcifying species. Differences in distribution patterns indicate that the decreasing pH modified the structure and biological traits of polychaete assemblages independent of changes in habitat. A detailed taxonomic analysis highlighted species-specific responses to OA, with closely related species having opposing responses to decreasing pH. This resulted in an increase in the abundance of filter feeders and herbivores with decreasing pH, while sessile polychaetes disappeared in the extreme low pH zones, and were replaced by discretely motile forms. Reproductive traits of the polychaete assemblages changed as well, with brooding species dominating the most acidified zones. The few taxa that were abundant in extreme low pH conditions showed high tolerance to OA (e.g. Amphiglena mediterranea, Syllis prolifera, Platynereis cf. dumerilii, Parafabricia mazzellae, Brifacia aragonensis), and are promising models for further studies on the responses of benthic organisms to the effects of reduced pH.


KEY WORDS: Annelida · Algal cover · Ocean acidification · Hard bottoms · pH gradient · Covariation · Mediterranean Sea · Functional trait analysis


Full text in pdf format
Supplementary material 
Cite this article as: Gambi MC, Musco L, Giangrande A, Badalamenti F, Micheli F, Kroeker KJ (2016) Distribution and functional traits of polychaetes in a CO2 vent system: winners and losers among closely related species. Mar Ecol Prog Ser 550:121-134. https://doi.org/10.3354/meps11727

Export citation
Mail this link - Contents Mailing Lists - RSS
- -