Structural and Functional Analyses of Motile Fauna Associated with Cystoseira brachycarpa along a Gradient of Ocean Acidification in a CO2-Vent System off Panarea (Aeolian Islands, Italy)
, Rocco Auriemma *, Cinzia De Vittor, Federica Relitti, Lidia Urbini, Martina Kralj and Maria Cristina GambiRound 1
Reviewer 1 Report
The topic is really interesting and important. I would like to mention three major elements that characterize the paper, namely: the importance of the topic, the timeliness and the need to develop knowledge on this topic and the modern way of approaching and conducting the study. The approach and description is at a high level of European research in the last decade and responds to the needs of further development of knowledge of the Cystoseira habitat. Moreover, the growing lack of taxonomy studies, implicitly of taxonomists conducting research, raises the importance of this study. Such studies involve a massive effort and then the article deserves another little effort to be enhanced.
Introduction. The subject is well documented.
For the material and methods, it is not specified after which the author developed the classification of traits, please indicate the sources.
Results. Please pay attention to the nominated species, many of them are not italic style in the paper.
In the discussion section I recommend a small discussion on the relationships within the carbonate system involved in the acidification phenomena during the study period.
Author Response
The reply to the Reviewer is in the attached Word file
Author Response File: 
Author Response.docx
Reviewer 2 Report
Review
Paper title: Structural and functional analyses of motile fauna associated with Cystoseira brachycarpa along a gradient of ocean acidification in a CO2-vent system off Panera (Aeolian Islands, Italy)
The authors conducted a study to reveal the possible effect of decreased pH on the communities associated with the macroalga Cystoseira brachycarp in a vent system in Italia. They considered this system as a model for testing the hypothesis that ocean acidification can alter benthic communities. They found clear zonation patterns in the diversity, structure, feeding groups and the degree of body calcification in invertebrates. The authors concluded that a decrease in pH does affect benthic communities and these results may have important implications for predicting changes in bottom fauna under acidification.
All these reasons explain the relevance of the paper by Valentina Esposito and co-authors submitted to "Journal of Marine Science and Engineering".
General scores.
The data presented by the authors are original and significant. The study is correctly designed. In general, the statistical analyses are performed with good technical standards. We authors conducted careful work which will attract the attention of a wide range of specialists focused on ocean acidification.
Recommendations.
The authors stated that they conducted the study in 2016 and 2018. However, both "2018" and "2019" are presented in the text. The authors should check the text.
The authors stated that their study may help "identify present and future winner and/or loser organisms to the future ocean of the Anthropocene". They should include information about potential winners and losers within their study area and adjacent areas in the case of the acidification scenario.
Figures 2, 3, 4, 5, 6, 7. The authors should increase the font and resolution of the sidebar.
Specific comments.
The authors did not provide the line numbering. Therefore I had to highlight my comments in the PDF.
Comments for author File: 
Comments.pdf
Author Response
The reply to the Reviewer is in the attached Word file
Author Response File: Author Response.docx
