Scale-Dependent Diversity Patterns in Subalpine Grasslands: Homogenization vs. Complexity

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

I read with great interest the manuscript entitled “Scale-dependent Diversity Patterns in Subalpine Grasslands: Homogenization vs. Complexity”. I have greatly appreciated the work done by the authors. It is a really comprehensive contribution on scale-dependent patterns of alpha and beta diversity in subalpine grasslands of the Central Balkan Mountains, in relation to reduced grazing.

Here below some suggestions and observations that I think may improve the manuscript in some parts.

 

Introduction

Line 70-79:  this part should be better placed in “study site”

Line 80: “We previously reported a clear distinction between pure grasslands (N-type) and areas with a mixture of grass and dwarf shrub vegetation (V-type) … “. Actually the authors haven’t reported this distinction between N and V type before, if not in the abstract; thus, I suggest to introduce here the distinction.

92-104: this part should be better placed in “material and methods”, “Field sampling design”

 

Materials and Methods

116-119: please provide here also some information on phytoclimate (e.g. form Rivas-Martínez, S., Penas, A. & Diaz, T.E. 2004: Biogeographic map of Europe. Cartographic Service, University of Léon, Spain)

139: (Error! Reference source not found.A)” please correct typos

Resuts

233: “51 species. ,Specific” please correct typos

235-249: species names should all be in italics

Conclusions: Unify the font size with the rest of the text; this section could be expanded

Author Response

Reviewer 1: I read with great interest the manuscript entitled “Scale-dependent Diversity Patterns in Subalpine Grasslands: Homogenization vs. Complexity”. I have greatly appreciated the work done by the authors. It is a really comprehensive contribution on scale-dependent patterns of alpha and beta diversity in subalpine grasslands of the Central Balkan Mountains, in relation to reduced grazing.

Response: Thank you very much for taking the time to review this manuscript. We appreciate the positive assesment of our work.

Please find the detailed responses below and the corresponding corrections in track changes in the re-submitted files

Point-by-point response from authors to comments and suggestions

Comment 1: Introduction Line 70-79:  this part should be better placed in “study site”

Response 1: Thank you. We agree with your suggestion

In Lines 67-69 we highlighted the major research gap in the study field we addressed. To explore to related patterns, we needed appropriate study objects and specific methodology. In the related text we introduced our study area (lines 72-84 in the first version of the manuscript) and explained why this area was appropriate and similarly, we had to introduce and explain our novel and specific methodology (lines 85-104 in the first version). During the revision we shortened these texts focusing to general information while specific details were moved to the Material and Methods section. You can find the changes at lines 144-146.

Comment 2: Line 80: “We previously reported a clear distinction between pure grasslands (N-type) and areas with a mixture of grass and dwarf shrub vegetation (V-type) … “. Actually the authors haven’t reported this distinction between N and V type before, if not in the abstract; thus, I suggest to introduce here the distinction.

Response 2: Thank you for pointing out this ambiguity. We made changes in the main text for more clarity (lines 86-88)

Comment 3: 92-104: this part should be better placed in “material and methods”, “Field sampling design”

Response 3: We agree with your suggestion and have relocated this information to Materials and Methods at lines 199-201.

 

Comment 4: Materials and Methods

116-119: please provide here also some information on phytoclimate (e.g. form Rivas-Martínez, S., Penas, A. & Diaz, T.E. 2004: Biogeographic map of Europe. Cartographic Service, University of Léon, Spain)

Responce 4: We appreciate your suggestion. We consider the presented climatic data sufficient for the readers to understand the study area, and adding more details could overload the text with information and citations.

Comment 5:139: (Error! Reference source not found.A)” please correct typos

Response 5: Thanks. This was a technical mistake. It is now corrected.

Comment 6: Resuts 233: “51 species. ,Specific” please correct typos

Response 6: Thanks. Corrected (L280)

Comment 7: 235-249: species names should all be in italics

Response 7: Of course, thank you.

Comment 8: Conclusions: Unify the font size with the rest of the text; this section could be expanded

Response 8: Thanks. We used the template, provided by LAND, but we will pay additional attention before re-submitting. We completely rewrote the Conclusion.

Reviewer 2 Report

Comments and Suggestions for Authors

Dear authors, I have read with pleasure your article and it is really a good study of grasslands, the article is well written and gives a clear view of the floristic diversity. Nevertheless, I would like to give you a small piece of advice: it is good that you put authorship to the taxa, at least the first time they are named in the text. In references, the manual numbering in parentheses ( ) is unnecessary.

Author Response

Reviewer 2: Dear authors, I have read with pleasure your article and it is really a good study of grasslands, the article is well written and gives a clear view of the floristic diversity. Nevertheless, I would like to give you a small piece of advice: it is good that you put authorship to the taxa, at least the first time they are named in the text. In references, the manual numbering in parentheses ( ) is unnecessary.

Response: Thank you for your positive assessment of our work. We took your advice and added the authors' names to the taxa. We removed the unnecessary parenhthesis from the reference list.

Reviewer 3 Report

Comments and Suggestions for Authors

“Scale-dependent Diversity Patterns in Subalpine Grasslands: Homogenization vs. Complexity.” is a good research topic, which investigates the diversity patterns of different vegetation types in the subalpine grasslands of the Central Balkan Mountains following reduced grazing. It is not only crucial for understanding ecosystem dynamics and formulating effective restoration strategies but also holds significant practical importance for studying the direction of vegetation transformation and its impact on biodiversity. Overall, the research topic is of significant importance, the study design is rational and innovative, and the data are abundant with scientific analytical methods. However, there are some important points that need to be improved. The following are the specific review comments:

 

In Materials and Methods of the manuscript:

• Field sampling design: The selection of study sites has taken into account the consistency of environmental factors to some extent. However, with only six study sites chosen, the sample size is relatively small and may not be able to fully represent the diversity changes of the entire subalpine grassland ecosystem. It is suggested that the authors explain the specific criteria for selecting these six sites to enhance the representativeness and reliability of the research results.
• Vegetation data: The comparative study design for N-type and V-type vegetation is rational, which helps to clearly show the differences in diversity patterns between different vegetation types. However, during the experimental process, although some environmental variables were controlled as much as possible, potential factors that may affect vegetation diversity, such as soil microbial communities and micro-topography, were not investigated and analyzed in detail. It is suggested that the authors supplement relevant data or analyze the possible impacts of these factors on the results in the discussion section.

 

In the Discussion of the manuscript:

• Although the manuscriptmentions the climatic characteristics and soil types of the study area, there is a lack of in-depth analysis and discussion on the role of those factors (such as climatic conditions, soil properties, and topography) in the formation of different vegetation types and changes in diversity. It is suggested that the interaction between those factors and grazing intensity on vegetation diversity be further explored in the discussion section.
• It is suggested that the authors make more explicit predictions about the long-term dynamic trends of vegetation. Based on the current research results and combined with existing ecological theories and related studies, the possible succession directions, potential threats, and necessary conservation measures in the future should be explored to enhance the foresight and practical value of the study.

Comments on the Quality of English Language

The language of the manuscript is basically fluent, but there are some grammatical errors and inaccurate expressions. For example: in the sentence “Functionally, the V-type species were taller, grew more slowly, and had thicker, more lignified leaves compared to the N-type species………”, “grew more slowly” is not consistent with “were taller” and “had thicker………” in terms of grammatical structure. It can be changed to “growing more slowly” to make the expression clearer. It is suggested that the authors carefully proofread the whole text to improve the language quality of the manuscript.

Author Response

Reviewer 3: "Scale-dependent Diversity Patterns in Subalpine Grasslands: Homogenization vs. Complexity.” is a good research topic, which investigates the diversity patterns of different vegetation types in the subalpine grasslands of the Central Balkan Mountains following reduced grazing. It is not only crucial for understanding ecosystem dynamics and formulating effective restoration strategies but also holds significant practical importance for studying the direction of vegetation transformation and its impact on biodiversity. Overall, the research topic is of significant importance, the study design is rational and innovative, and the data are abundant with scientific analytical methods. However, there are some important points that need to be improved. The following are the specific review comments:

Response from authors: Thank you for taking the time to review this manuscript. We appreciate your positive assessment of our work. We found your suggestions valuable and made the corresponding changes where necessary.

Please find the detailed responses below and the corresponding corrections in track changes in the re-submitted files.

Point-by-point response from authors to comments and suggestions

Comment 1: In Materials and Methods of the manuscript:

Field sampling design: The selection of study sites has taken into account the consistency of environmental factors to some extent. However, with only six study sites chosen, the sample size is relatively small and may not be able to fully represent the diversity changes of the entire subalpine grassland ecosystem. It is suggested that the authors explain the specific criteria for selecting these six sites to enhance the representativeness and reliability of the research results.

Response 1: Thank you, we understand the reasons for pointing out this potential shortcomming of our work.

Given our focus on exploring small-scale phenomena—biotic factors and drivers—rather than large-scale drivers like climatic or elevational gradients, we conducted our study in a limited area with relatively uniform climatic and grazing conditions.We compensated for the reduced number of sites by employing a highly precise species distribution and abundance assessment, recording species presence in 1040 microquadrats per transect. With two transects per site (N-type and V-type) across six sites, this yielded a total of 12,480 microquadrats. While acknowledging that the robustness of results is influenced by the number of sampled sites, we also recognize the inherent trade-off between site number and the high-precision data obtained through our labor-intensive sampling methodology.

For more clarification on that, in the resubmission, we provide a reformed Figure 1, illustrating the study area and the sampling design, concentrating on the advantages of the applied methodology.

 

Comment 2: Vegetation data: The comparative study design for N-type and V-type vegetation is rational, which helps to clearly show the differences in diversity patterns between different vegetation types. However, during the experimental process, although some environmental variables were controlled as much as possible, potential factors that may affect vegetation diversity, such as soil microbial communities and micro-topography, were not investigated and analyzed in detail. It is suggested that the authors supplement relevant data or analyze the possible impacts of these factors on the results in the discussion section.

Response 2: We acknowledge your concern regarding the potential influence of varying environmental conditions. We maintain that while differences may exist between sites, local conditions within each site remain consistent due to the close proximity of N-type and V-type stands. In our previous study in the area we have included supplementary data on environmental proxies for each stand, specifically altitude, slope, aspect, and soil depth (see Terziyska, T.; Tsakalos, J.; Bartha, S.; Apostolova, I.; Sopotlieva, D.; Zimmermann, M. Z.; Szabo, G.; Wellstein, C. Species and Functional Differences between Subalpine Grasslands with and without Dwarf Shrub Encroachment. Plant Biosyst. - Int. J. Deal. Asp. Plant Biol. 2020, 154 (4), 568–577. https://doi.org/10.1080/11263504.2019.1651780). Nevertheless, we also prepared a supplement for this manuscript, providing details on conducted analysis, which results support our a priori assumption that condition variation had a negligible effect on local and regional diversity. We have briefly discussed this aspect in the Discussion section (lines 388-404).

Comment 3: In the Discussion of the manuscript:

Although the manuscript mentions the climatic characteristics and soil types of the study area, there is a lack of in-depth analysis and discussion on the role of those factors (such as climatic conditions, soil properties, and topography) in the formation of different vegetation types and changes in diversity. It is suggested that the interaction between those factors and grazing intensity on vegetation diversity be further explored in the discussion section.

Response 3: Thank you for highlighting this aspect.

All species in the study area are typically present at this altitude and the effects of climate and soil conditions on their distribution and abundance is strongly mediated by grazing pressure. We’ve made a few changes in the text for a better understanding of that matter (lines 388-404).

Comment 4: It is suggested that the authors make more explicit predictions about the long-term dynamic trends of vegetation. Based on the current research results and combined with existing ecological theories and related studies, the possible succession directions, potential threats, and necessary conservation measures in the future should be explored to enhance the foresight and practical value of the study.

Response 4: We find this suggestion valuable, thank you.

Additional information about the future prospects and conservation measures is added in the Conclusion and the Abstract (lines 453-459 and lines 32-33, respectively).

Comment 5: Comments on the Quality of English Language

The language of the manuscript is basically fluent, but there are some grammatical errors and inaccurate expressions. For example: in the sentence “Functionally, the V-type species were taller, grew more slowly, and had thicker, more lignified leaves compared to the N-type species………”, “grew more slowly” is not consistent with “were taller” and “had thicker………” in terms of grammatical structure. It can be changed to “growing more slowly” to make the expression clearer. It is suggested that the authors carefully proofread the whole text to improve the language quality of the manuscript.

Response 5: Thank you for catching this grammatical error.

Our native English-speaking author (JT) revised the language thoroughly.

Reviewer 4 Report

Comments and Suggestions for Authors

Dear Authors,

With substantial interst I have read Your manuscript titled „Scale-dependent Diversity Patterns in Subalpine Grasslands: Homogenization vs. Complexity”. Generally, I have found it well-planned and well-written. Nevertheless, I have found some imprefections, which (in my opinion) sould be improved ot at least clarified before an eventual publication. I have listed them below:

1. I suggest to add the main conclusion in Abstract section.
2. In my opinion text in lines 87-104 suits better to chapter Material and methods.
3. Material and methods. How were the study sites chosen? I think, that the concise Table presenting the similarity and differences (abiotic and biotic conditions) among study sites would be really need.
4. Caption of Figure 1 should be more concise. The content should be self-explanatory, perhaps it should be a bit rearranged to present the way of data collection in transects and subtrancects.
5. The Latin names of taxa should be written in italics.Please add the authors of names.
6. Table 1. In my opinion the values of mean and SD are sufficient, the range might be omitted.
7. Conclusions sounds as the Summary. This section should be rewritten. Please point out the novelty of Your findings and indicato the directions of future studies.

Author Response

Reviewer 4: Dear Authors,

With substantial interst I have read Your manuscript titled „Scale-dependent Diversity Patterns in Subalpine Grasslands: Homogenization vs. Complexity”. Generally, I have found it well-planned and well-written. Nevertheless, I have found some imprefections, which (in my opinion) sould be improved ot at least clarified before an eventual publication. I have listed them below:

Response: We are grateful for your interest in our research and the constructive and valuable feedback you provided.

Please find the detailed responses below and the corresponding corrections in track changes in the re-submitted files.

Point-by-point response from the authors to Comments and Suggestions

Comment 1: I suggest to add the main conclusion in Abstract section.

Response 1: Thank you. We completely agree. You can find the main contributions from our study highlighted at the end of the Abstract (lines 25-30).

 

Comment 2: In my opinion text in lines 87-104 suits better to chapter Material and methods.

Response 2: In Lines 67-69 we highlighted the major research gap in the study field we addressed. To explore to related patterns, we needed appropriate study objects and specific methodology. In the related text we introduced our study area (lines 72-84 in the first version of the manuscript) and explained why this area was appropriate and similarly, we had to introduce and explain our novel and specific methodology (lines 85-104 in the first version). During the revision we shortened these texts focusing to general information while specific details were moved to the Material and Methods section.

We agree with your suggestion and have removed the redundant information from the Introduction (lines 101-106).

Comment 3: Material and methods. How were the study sites chosen? I think, that the concise Table presenting the similarity and differences (abiotic and biotic conditions) among study sites would be really need.

Response 3: Thank you for the suggestion.

In our previous study in the area we have included supplementary data on environmental proxies for each stand, specifically altitude, slope, aspect, and soil depth (see Terziyska, T.; Tsakalos, J.; Bartha, S.; Apostolova, I.; Sopotlieva, D.; Zimmermann, M. Z.; Szabo, G.; Wellstein, C. Species and Functional Differences between Subalpine Grasslands with and without Dwarf Shrub Encroachment. Plant Biosyst. - Int. J. Deal. Asp. Plant Biol. 2020, 154 (4), 568–577. https://doi.org/10.1080/11263504.2019.1651780). Nevertheless, we prepared a supplement also for this manuscript, providing details on conducted analysis, the results from which support our a priori assumption that condition variation had a negligible effect on local and regional diversity. We have briefly discussed this aspect in the Discussion section (lines 388-404).

We perceive the existing Fig. 2 as an illustration of the main biotic conditions, as it present the relative abundances of the main plant groups – dominant and subordinat species in every vegetation stand.

Comment 4: Caption of Figure 1 should be more concise. The content should be self-explanatory, perhaps it should be a bit rearranged to present the way of data collection in transects and subtrancects.

Response 4: Thank you for drawing our attention to this unclarity.

For more clarification on that, in the resubmission, we provided a reformed Figure 1 and the corresponding caption, illustrating the study area and the sampling design, concentrating on the advantages of the applied methodology.

Comment 5: The Latin names of taxa should be written in italics.Please add the authors of names.

Response 5: We respected your advice and added the authors' names to the taxa at first mention. All latin names are now in italics.

Comment 6: Table 1. In my opinion the values of mean and SD are sufficient, the range might be omitted.

Response 6: Thanks you. We did as you suggested (see Table 1)

Comment 7: Conclusions sounds as the Summary. This section should be rewritten. Please point out the novelty of Your findings and indicato the directions of future studies.

Response 7: Thank you. We completely agree and rewrote the Conclusion section.

You can find the main contributions from our study and information about the future prospects highlighted at the end of the Abstract and in the Conclusion (lines 25-33 and 446-459, respectively).

Round 2

Reviewer 3 Report

Comments and Suggestions for Authors

Accept in present form.