Diversity Patterns and Community Structure of the Ground-Associated Macrofauna along the Beach-Inland Transition Zone of Small Tropical Islands

Round 1

Reviewer 1 Report

Dear Authors

 

This is a very interesting manuscript that is well written. I have two suggestions for improvement:

• Accumulation curves should be presented for each habitat and the habitat alpha diversity may need to be compared using rarefaction curves
• The use of the diversity Indices is outdated. The authors should use Hill Numbers. The Hill numbers use a diversity profile organized in four orders (q) as follows: i) species richness (S) (q = 0), taken as a count of the number of species in a particular site; ii) the exponential Shannon-Wiener (H´) (q = 1); iii) the inverse of Simpson´s concentration index (D) (q = 2) and iv) Berger-Parker index (d) (q = 3). The Hill numbers are very rich in information, since they combine information on species richness, species rarity (species relative abundances) and species dominance (see also explanation in the file in attachment)

Hill, M.O. Diversity and Evenness: A Unifying Notation and Its Consequences. Ecology 1973, 54, 427–432, doi:https://doi.org/10.2307/1934352

Jost, L. Partitioning diversity into independent alpha and beta components. Ecology 2007, 88, 2427–2439, doi:https://doi.org/10.1890/06-1736.1

Chao, A., Chiu, C. H., & Jost, L. (2014). Unifying species diversity, phylogenetic diversity, functional diversity, and related similarity and differentiation measures through Hill numbers. Annual review of ecology, evolution, and systematics, 45, 297-324.

 

• The variation in species composition among habitats, or beta diversity, can be decomposed into replacement, nestedness and richness difference. A debate is ongoing in the literature concerning the best ways of computing and interpreting these indices. The merits of the Carvalho (Carvalho et al., 2013) approach (beta diversity, decomposed into replacement and richness difference) were recently recognized (Legendre (2014). Indeed, these indices are complementary; they can help researchers understand different aspects of ecosystem functioning and should be both applied (see example in Matthews, et al. 2019) even putting some of results in Supplementary materials. Therefore, the authors should take into consideration beta richness differences (Carvalho model).

 

Carvalho, J.C., et al. (2013). Measuring fractions of beta diversity and their relationships to nestedness: a theoretical and empirical comparison of novel approaches. Oikos, 122: 825–834.

Legendre, P. (2014). Interpreting the replacement and richness difference components of beta diversity. Global Ecology and Biogeography, 23(11), 1324-1334.

Matthews, T., et al.. (2019). Differential turnover rates and temporal beta-diversity patterns of native and non-native arthropod species in a fragmented native forest landscape. Ecography, 42: 45–54.

 

Comments for author File: Comments.pdf

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report

Line 11- Should be “Where two”

Line 320 – if it is a young age, can you put a general estimate of age.

329- Your final sentence of the discussion is confusing and I am unsure what you are trying to say.

Overall Comments I like this study it is unique, interesting but simple. I think it important to have these types of studies to help describe and understand the natural world. One minor thing is that this study only sampled each transect once, although I do not think this is a big issue, I do think it should be highlighted as a potential issue as sampling more the once at different times of year could change or enhance this study. As it is a remote island study, I understand that it is difficult to do this, and only think the authors should mention it as a potential issue.

Lastly, I believe insular should be quickly defined. It is a bit jargony, and if defined it would help readers understand what the authors are saying a bit quicker. Just a stumbling block while I read through, and others may have a similar problem.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf