The Influence of Salinity Gradient and Island Isolation on Fauna Composition and Structure of Aquatic Invertebrate Communities of the Shantar Islands (Khabarovsk Krai)

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

The paper is interesting; it has a bit too much information so it is not easy to follow. I could not access Supplementary materials to look at Table S1 and S2 as I think I would have more suggestions upon seeing that. I am not sure that your identifications to species level are correct when it comes to some groups, especially Diptera. Additionally in the text, some things are mentioned from nowhere and it is quite unclear at some point why something is suddenly there when it was never mentioned before. I think you should try to make the text more understandable and easier to follow, as it was at some point quite difficult. I would include tables in the main portion of the text.

Comments on the Quality of English Language

Please improve the English language at some parts, it is more or less quite good, but still there are some mistakes and it needs improvement.

Author Response

Thank you very much for taking the time to review this manuscript. Please find the corrections in track changes in the re-submitted files.

 ANSWER on comments: Thank you for your high opinion of our work. According to the Reviewer’s comments, Introduction, Discussion, and other chapters have been expanded and improved, and all the parts of the investigation do not seem new and unexpected to the readers. We have improved the description of the salinity gradient and its role in our research in the text. Specification of what our research adds to the literature has been added to the text. Added information on the importance of comparing different ecological groups of hydrobionts. Hypotheses have also been added. As the tables of the species lists are too large, we are considering keeping them in the Supplement.

            We have also revised the English flow and grammar throughout the ms.

Reviewer 2 Report

Comments and Suggestions for Authors

The authors performed a local study to determinate the spatial variation in the assemblage of invertebrates (zooplankon, meiofauna and macroinvetrebrates)

The results permit to conclude a spatial variation according to the salinity gradient and latitude, increasing the knowledge in the main water bodies from Shantar Island, Russia.

The manuscript is well written, and I recommend this manuscript to publication.

Author Response

Thank you very much for taking the time to review this manuscript and thank you for your appreciation of our work.

Reviewer 3 Report

Comments and Suggestions for Authors

General Comments:

The Authors focused on assessing for the first time the community and diversity of a peculiar ecosystem. The Authors analyze the species composition and distribution of freshwater invertebrates in Shantar Island’ inland waters. I found the paper very interesting and well-written. I recognise the value of comparing the diversity of the hydrobiont fauna on the basis of the original and literature data. The paper is well conducted and the flow is good, I suggest emphasizing more the concept of your comparison about hydrobionts. Why compare the specific taxon of hydrobyonts? Please motivate it, and write a hypothesis that you then will test. In this regard, I suggest revising the aims and structuring results and discussion accordingly – considering that the most important topic is about community diversity and the comparison of hydrobyonts with community, so have to be considered in all the papers.

I have a few issues for the Authors. I suggest rephrasing some parts of the manuscript. More information is provided below along with the rebuttal to the Authors. The specific comments are given to each section, as I cannot find continuous line numbering in the ms. This paper could increase the knowledge in the field, and prior to being published needs a MAJOR revision by the Authors.

Specific Comments:

1.      Title: from here and in the ms, if salinity is important for your aims, more emphasis should be given to chemical parameters (i.e., salinity) if the salinity gradient is then fundamental for diversity assemblages. Otherwise, you might consider revising title and ms.

2.      Introduction: please improve the State-of-the-art by adding also more recent papers on this topic. Also, Introduction should be revised to introduce the topic of “species composition and distribution of freshwater invertebrates in lakes, streams and rivers”. To do that, please quote also recent publications, such as:

- https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0168908

- https://link.springer.com/article/10.1007/s12237-022-01117-2

- https://www.sciencedirect.com/science/article/pii/S0304377022000419?casa_token=wC5rZ9eUPjkAAAAA:U_YSyGvOktk-PaDAP5BHgMixsiaf_jCIj2i_OyRoo7DqVftItIXoM5G_PCkYigJFk9ubcLABJ2Q

- https://onlinelibrary.wiley.com/doi/full/10.1111/brv.12848

- https://www.mdpi.com/2075-4450/13/10/911

- https://link.springer.com/article/10.1007/s12210-022-01124-2

- https://onlinelibrary.wiley.com/doi/full/10.1111/brv.12903

-https://iwaponline.com/aqua/article/doi/10.2166/aqua.2023.081/97499  

 

3.      Abstract: I would add a sentence on the application of your results in a wider perspective.

4.      Introduction: please add before and in the aims what you are adding to the literature with your paper

5.      Aims: going to your aims, you should better define what you mean by a “white spot” and also provide more information on the already conducted studies on the same topic. Also, specify what your study provides as new to the literature. Also, when rephrasing your aims, I suggest emphasizing more the concept of your comparison about hydrobionts. Why compare the specific taxon of hydrobyonts? Please motivate it, and write a hypothesis that you then will test.

6.      Methods, study area: please split this long sentence. “…hydrological and hydrochemical characteristics: continental lotic” into “..hydrological and hydrochemical characteristics. Among these, continental lotic (..”

7.      Methods, when you defined the continental lotic, continental lentic freshwaters, insular lotic, insular lentic freshwaters, and brackish waterbodies, please quote the papers that describe biodiversity in these ecosystems

8.      Methods, please quote the protocol you adapted/used to sample zooplankton, macrophytes, and other organisms.

9.      Methods, is the method used to sample the same for each type of ecosystem? I assume that sampling the bottom of a temporary river or pond is not the same as sampling a deep river or pond, right? This should be better described.

10.  Methods, I strongly suggest adding a figure to explain your sampling methods so that audience could better follow your findings.

11.  Methods, I would recommend splitting methods into 1. Study area, 2. Field sampling and lab analysis, 3. Statistical analysis (how you use and analyse your data, and statistics).

12.  Data analysis, I would explain more on the non-metric multidimensional scaling (nMDS) ordination. How is the output of your results? What to expect?

13.  Results, figure 3: here and in methods: why using different units of measurement for invertebrates (e.e., ind/m2, ind/cm2, etc)? also, please describe what is meiofauna vs macrofauna in methods by also describing the units here used. However, if meiofauna is given by ind/m2, please explain this better. If literature do as it, please quote references so

14.  Results, what does it mean “в различных типах водоемов были”? please translate it to make the audience understand

15.  Results, I would suggest to add a table in which you put the diversity you found – In order to make the text more readable (you can delete some species names and put in the table)

16.  Results, what about “3.2. Variation of the integral characteristics of the fauna along the salinity gradient”? the results should focus more on your aims, which are: 1. Diversity of inland water of this island, then 2. Comparison with other communities. I expect to also have a figure on MDS to show your findings.

17.  Results, why in 3.2 the variation is on salinity? What about the other chemical-physical parameters?

18.  Results, both sections 3.1. and 3.2 are too descriptive: I suggest reducing it a bit and using a table to put some of the information occurring there

19.  Discussion, please open the discussion with an introductive recap of what you found

20.  Discussion, figure 4 seems more like results, right? I would move it to Results and explain it more in the Result section.

21.  Discussion: in general and for this sentence “All freshwater streams and part of the lakes were inhabited by communities of the second type.” I would discuss it providing an ecological point of view: why those streams were inhabited by this taxa? Is it historically due? Or is it for competition? Is it for contaminants? Etc

22.  Discussion, what about this paragraph? 4.3. Effects of insularity and latitudinal patterns in species richness? It seems like new: you should prepare the reader from Intro, aims and methods to which direction the paper will go. Please define it better.

23.  Discussion, please discuss your results with the same patterns found in other peculiar regions in the world.

24.  Discussion and conclusions: I strongly suggest adding a few sentences on (i) the importance of your findings considering the current literature (So, what are you adding to literature?) and (ii) the application of your results. Also, please add a paragraph on the limits/limitations of your study.

 

25.  In the end, the flow of your ms is good, anyway I strongly suggest revising the English flow and grammar throughout the ms in order to allow readers to understand better your findings.

Comments on the Quality of English Language

the flow of your ms is good, anyway I strongly suggest revising the English flow and grammar throughout the ms in order to allow readers to understand better your findings.

Author Response

Thank you very much for taking the time to review this manuscript. Please find the detailed responses below in the attachment and the corresponding corrections in track changes in the re-submitted files.

Please see the attachment.

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

I just had a look at the Tables with identifications and that is horrible, first of all there is in the tables Cyrillic letters (I can read it as I am Slavic and learned it, but in general people cannot understand that), unacceptable. Secondly I have had a look at Diptera order, where in Simuliidae you do not have Simuliium sp., which is unbelievably odd, but let say it is correct (doubt it). Then you have put Dixa sp., Tipula sp., Pedicia sp., Dicranota sp., Eloeophila sp., Dicranomyia gr. autumnalis in Chironomidae family, that is more than wrong and then you do not write to which families they all belong to, either do not write families at all or write each family for each species in all orders. And in lotic habitats you do not have any Empididae (Chelifera sp., Wiedemannia sp, Clinocera sp.) but you get Chelifera sp. in lentic, I find that odd as Empididae do occur in lentic, but majority species are confined to lotic habitats. I am primarily not satisfied with the supplementary material, I think there is most probably a lot of mistakes in it and as I am only expert in Diptera, I can see it only here.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

The Authors addressed most of my comments and improved the ms.  I just strongly recommend some specific modifications to implement their ms.

1.       Aims and along the ms: I suggest emphasizing more the concept of your comparison about hydrobionts. Why compare the specific taxon of hydrobyonts? Please check it and check if you motivate it along the ms, from aims/hypothesis to results/discussion sections.

2.       Methods, you should add if the method used to sample the same for each type of ecosystem. This part “Most of the investigated waters were quite shallow, except for several large rivers and Bolshoe Lake, but anyway, all the sampling was performed from the shore. The sampling method was therefore standardised and didn't depend on the type of water body, but on the habitat. Samples of macrozoobenthos on soft substrates were sampled using a D-frame aquatic net, samples from vegetation and roots from the littoral zone were collected with manual hemisphere sampler.” Should be added with simply words.

3.       Along the ms, as salinity is the most important factors affecting hydrobyonts distribution, you should specify from introduction this. So why salinity is the most important factor? What about the other chemical-physical parameters? Please add the motivation in Intro or Methods – relying on this: “is the main factor determining the distribution of organisms in estuarine water bodies (Getz, Eckert, 2023).”

4.       In general, check that there is a logic red line between the sections of your ms according to your “new” aims. Also, the sections (Intro, Methods, Results, and discussion) should be set following the same logic and order.

5.       To reach the audience, check English flow along the ms, like some sentence can have a better flow. For instance, L166: avoid “of…of”, rephase.

6.       As general suggestion, I recommend checking the length of each section’s text in order to avoid repetition and too written parts.

Some minor comments:

L171 check the double comma.

L175: about the three primary hypotheses: here, to make easier to be followed by a wider audience, I strongly suggest adding motivation and references to motivations.
e.g. “Latitudinal trends in the variability of species richness and biogeographic struc-180 ture of the fauna are closely related for different groups of freshwater invertebrates.” Who can say that? It’s not a proper hypothesis..
then, “Different ecological groups of organisms exhibit variable responses to changes in 177 environmental factors”: which environmentalfactors? What about salinity?
“the structure of aquatic insular com-182 munities may differ significantly from those on the mainland.” Reference?

L185: change will into might contribute

L198: add -s to “categorie”

L349: why are species considered rare? What do you mean?

L499: check the double “of” in the sub heading

L500: in this new “result” part there are several parts that sounds like discussion: please check it and delete them from here and eventually move to discussion.

 

L546: CHEck double space

Comments on the Quality of English Language

English is fine, and can be improved 

Author Response

Please see the attachment.

Author Response File: Author Response.pdf