The Diversity and Community Pattern of Liverworts on Sygera Mountain, Tibet

Round 1

Reviewer 1 Report

Dear colleagues,

I have read your paper regarding the diversity of liverworts in Sygera Mountain at the Qinghai-Tibet Plateau. I appreciate all your hard work. 
In order to improve your manuscript, I will share some comments and doubts.

TITLE

It is customary to give some more information regarding the geographic location of the study area. I suggest you add the name of the plateau and/or the name of the country.

INTRODUCTION

The introductory section does not exhaustively cover all the work that has been done with bryophytes and mountains. I suggest you look further at different works and continents.

lines 53-54 - this statement is rather obvious - the researchers that have worked with elevation don't generally claim that elevation is an important variable "per se". Please rephrase.

line 69 - There are some studies that show that Sphagnum and Takakia are the oldest taxa on Earth. Please check Laenen et al., 2014 [Nature Communications] to discuss this issue.

RESULTS

I could not find any information on the taxonomic richness and diversity of your data. In the methodological section, you state that the specimens are available at the Herbarium of China Agricultural University (acronym?), but you do not say which Classes, Orders, Families, Genera, or Species are represented. I understand you have already published some data on Gu et al., 2022 [Forests], but even there you only have information on epiphytic species. This is important information and must be included - at least in Supplementary material, discriminating at which elevation the species were found.

Please check also:

Line 206 - To which canonical axis are you referring to - (x,y,z)? It would be helpful if you could state the variance explained by each of them. If indeed you are considering the first three-axis, 45,22% is lower than other studies regarding bryophyte elevation gradients (e.g. Coelho et al., 2021 [Diversity]).

DISCUSSION

I'm sure that your reading of further literature on islands will help you to support your affirmations regarding the importance of different factors, such as area at each elevation, and vascular plant cover, for instance.

Dear colleagues,

I believe you could improve the quality of the scientific English language, by removing adjectives/qualificatives from the text. These words/expressions may distract the reader. Without them the text becomes more straightforward and sound.

Please check all the text. Here are some examples:

line 143 - "boasts"

line 146 - "harnessed the computational capabilities"

line 157; line 170 - "rigorously"

A minor typo:

line 167 - "ued/used"

Thank you.

Author Response

Dear reviewer,

On behalf of all co-authors, we appreciate you very much for the positive and constructive comments on our manuscript. So, we did reprocessed the relevant data and discussed each comments and suggestions, and revised the manuscript, including figures, tables, paragraphs, and sentences, etc.. We hope you find the revised manuscript satisfactory. Thank you again for your suggestions.

Truly yours

Xiaoming Shao

TITLE

1.It is customary to give some more information regarding the geographic location of the study area. I suggest you add the name of the plateau and/or the name of the country.

Response: Based on your comments, the title has been changed: The Diversity and Community Pattern of Liverworts in Sygera Mountain, Tibet.

INTRODUCTION

2.The introductory section does not exhaustively cover all the work that has been done with bryophytes and mountains. I suggest you look further at different works and continents.

Response: The introduction has been revised to include a paragraph based on your comments. “Liverworts, among the earliest groups of land plants, have an evolutionary history that can be traced back with ages ranging from 29.7 to 37.6 million years ago [24,25]. They are usually non-vascular bundles and lack the special tissue system found in more evolved plants [26]. On the contrary, they have a simple structure, either thalloid (flat and banded) or leafy [27]. They mainly fix themselves on wet substrates, from soil, rotten wood to rocks, usually in a cool or humid environment [28]. Some species have even adapted to more challenging terrain, such as bare rocks or tree trunks. In liverworts, rhizoids are recognized as slender, hair-like appendages primarily functioning to secure the plant to its substrate. While they do assist in the absorption of water and nutrients, this role is somewhat limited compared to the entire plant body [29,30]. Liverworts show innumerable adaptability to survive in different environments. Many species are resistant to dehydration, can withstand drying, and then rehydrate when water is available [31]. Others form a symbiotic relationship with fungi to promote nutrient absorption [32]. They thrive in habitats such as forests, riverbanks and moist meadows [33]. However, their adaptability also enables them to settle in a range of habitats from tropical rain forests to Arctic tundra [34,35].” Please see the revised manuscript “1. Introduction”.

3.lines 53-54 - this statement is rather obvious - the researchers that have worked with elevation don't generally claim that elevation is an important variable "per se". Please rephrase.

Response: Thank you for your comments. According to your suggestion, we have revised it into “Elevation reflects a series of interrelated biotic and abiotic determinants. As an elevation rises or falls, there are certain changes in climate, soil composition, and geographic processes [8-10].”

4.line 69 - There are some studies that show that Sphagnum and Takakia are the oldest taxa on Earth. Please check Laenen et al., 2014 [Nature Communications] to discuss this issue.

Response: Thank you for your comments. According to your suggestion, we have revised it into “Liverworts, among the earliest groups of land plants, have an evolutionary history that can be traced back with ages ranging from 29.7 to 37.6 million years ago.” Please see the revised manuscript “1. Introduction”.

RESULTS

5.I could not find any information on the taxonomic richness and diversity of your data. In the methodological section, you state that the specimens are available at the Herbarium of China Agricultural University (acronym?), but you do not say which Classes, Orders, Families, Genera, or Species are represented. I understand you have already published some data on Gu et al., 2022 [Forests], but even there you only have information on epiphytic species. This is important information and must be included - at least in Supplementary material, discriminating at which elevation the species were found.

Response: Thank you for your comments. This time the results were partially re-analyzed to illustrate the problem. At the same time, a list of species is displayed in Appendix S1. There are a total of 103 species of liverworts in our sample area, comprising 42 genera in 8 families (Appendix S1). Please see the revised manuscript at line 201-202.

6.Please check also:

Line 206 - To which canonical axis are you referring to - (x,y,z)? It would be helpful if you could state the variance explained by each of them. If indeed you are considering the first three-axis, 45,22% is lower than other studies regarding bryophyte elevation gradients (e.g. Coelho et al., 2021 [Diversity]).

Response: Thank you for your comments. According to your suggestion, we have revised it into “Canonical Correspondence Analysis (CCA) elucidated that the first two axes account for 50.6% of the total variance in the intricate relationships between liverwort communities and environmental gradients across varying elevations (Figure 5A).” Please see the revised manuscript “3. Results”.

DISCUSSION

7.I'm sure that your reading of further literature on islands will help you to support your affirmations regarding the importance of different factors, such as area at each elevation, and vascular plant cover, for instance.

Response: Thank you for your comments. We added this part to the discussion section. “The area available at each elevation level plays a determinative role in niche availability, potentially impacting species richness and community structure [54,55]. Notably, the lower elevations typically encompass larger areas, while mid-elevations tend to have a higher density of vascular plant cover, factors pivotal in shaping microhabitats and ecological interactions. This variance in spatial extent and plant density across elevations could modulate microclimatic conditions and substrate dynamics, critically influencing liverwort survival and distribution [56]. In our study of liverwort richness in Sygera Mountain, the bimodal distribution pattern strikingly mirrors similar findings in diverse mountainous regions, such as La Réunion [57], suggesting that mid-elevation zones often act as crucial ecological refuges. Integrating these dimensions into our ecological analysis promises to deepen our understanding of liverwort distribution patterns, contributing meaningfully to biogeographical and ecological conservation studies. This holistic approach, especially pertinent in island ecosystems, is instrumental in dissecting the intricate ways in which varied environmental factors orchestrate species diversity across different altitudinal gradients [58], thereby offering invaluable insights for effective biodiversity conservation and ecosystem management strategies in complex mountain ecosystems.” Please see the revised manuscript “4. Discussion”.

8. Comments on the Quality of English Language

I believe you could improve the quality of the scientific English language, by removing adjectives/qualificatives from the text. These words/expressions may distract the reader. Without them the text becomes more straightforward and sound.

Please check all the text. Here are some examples:

line 143 - "boasts"

line 146 - "harnessed the computational capabilities"

line 157; line 170 - "rigorously"

A minor typo:

line 167 - "ued/used"

Response: The comments regarding the quality of English in this article have been addressed and revised. Thank you for your correction.

Reviewer 2 Report

I am most bothered that there is no list of species. There is not even an indication of the number of species. Although the methodology seems sound, without the background information, it's not reliable.

Overall, the English is pretty good. However, to improve the English, it should always just be Sygera Mountain, not the Sygera Mountain.

Author Response

Dear reviewer,

On behalf of all co-authors, we appreciate you very much for the positive and constructive comments on our manuscript. So, we did reprocessed the relevant data and discussed each comments and suggestions, and revised the manuscript, including figures, tables, paragraphs, and sentences, etc.. We hope you find the revised manuscript satisfactory. Thank you again for your suggestions.

Truly yours

Xiaoming Shao

Comments and Suggestions for Authors

1.I am most bothered that there is no list of species. There is not even an indication of the number of species. Although the methodology seems sound, without the background information, it's not reliable.

Response: Thank you for your comments. This time the results were partially re-analyzed to illustrate the problem. At the same time, a list of species is displayed in Appendix S1. There are a total of 103 species of liverworts in our sample area, comprising 42 genera in 8 families (Appendix S1). Please see the revised manuscript at line 201-202.

Comments on the Quality of English Language

2.Overall, the English is pretty good. However, to improve the English, it should always just be Sygera Mountain, not the Sygera Mountain.

Response: The comments regarding the quality of English in this article have been addressed and revised. Thank you for your correction.

Reviewer 3 Report

The manuscript itself is interesting. However, I would like to include further chapter in discussion stressing the liverwort microhabitat abundance and changes over the gradient. Thus, not only overlapping but also the presence of potential microhabitat type and microclimate as You mentioned in the manuscript.

Also, please mention in adequate place within the manuscript the influence of light condition gradient i.e. sun radiation and its effects on liverworts (e.g. in high elevations).

I am not sure the rhizoids are serving for nutrient and water supply (page 76-77). Please add reference or correct that they minorly support liverwort supply in water in nutrient in comparison to whole body surface.

Author Response

Dear reviewer,

On behalf of all co-authors, we appreciate you very much for the positive and constructive comments on our manuscript. So, we did reprocessed the relevant data and discussed each comments and suggestions, and revised the manuscript, including figures, tables, paragraphs, and sentences, etc.. We hope you find the revised manuscript satisfactory. Thank you again for your suggestions.

Truly yours

Xiaoming Shao

1.The manuscript itself is interesting. However, I would like to include further chapter in discussion stressing the liverwort microhabitat abundance and changes over the gradient. Thus, not only overlapping but also the presence of potential microhabitat type and microclimate as You mentioned in the manuscript.

Response: Thank you for your comments. According to your suggestion, we added this part to our discussion. At the same time, the discussion part has also been greatly revised. Please see the revised manuscript “4. Discussion”.

2.Also, please mention in adequate place within the manuscript the influence of light condition gradient i.e. sun radiation and its effects on liverworts (e.g. in high elevations).

Response: Thank you for your advice. We added this part to our discussion:

“Furthermore, an essential aspect of this ecological complexity is the gradient of light conditions, particularly solar radiation, which significantly impacts liverwort communities. Solar radiation influences various physiological processes in liverworts, including photosynthesis, desiccation, and temperature regulation [64]. In areas with intense solar radiation, liverworts may experience increased stress, leading to adaptations like higher desiccation tolerance or the development of protective pigments [65]. The stratification of liverwort community structure along the solar radiation gradient is evident (Figure 5A), indicating that light conditions play a pivotal role in determining species distribution in these mountainous ecosystems (Figure 5B).” Please see line 370-378.

3.I am not sure the rhizoids are serving for nutrient and water supply (page 76-77). Please add reference or correct that they minorly support liverwort supply in water in nutrient in comparison to whole body surface.

Thank you for your correction. According to your suggestion, we have revised it into “In liverworts, rhizoids are recognized as slender, hair-like appendages primarily functioning to secure the plant to its substrate. While they do assist in the absorption of water and nutrients, this role is somewhat limited compared to the entire plant body.” Please see line 88-89.

Round 2

Reviewer 1 Report

Dear colleagues,

Thank you very much for improving the overall quality of your manuscript and providing more details regarding the sample. 

However, since you explicitly refer to elevation and aspect, I would like these variables to be discriminated in the Excel file with supplementary material. One way of doing it would be to include two columns per elevation, one regarding the number of collections made in the East, and the West, respectively. Another way of promoting your data would be to share them as GBIF dataset (https://www.gbif.org/dataset/search).

I believe that Figure 4 B is not well presented. The xx axis is off and the top whiskers of the boxplots are not visible.

Very best wishes,

No comments.

Author Response

Xiaoming SHAO

Department of Ecology and Ecological Engineering

College of Resources and Environmental Sciences

China Agricultural University

No.2 Yuanmingyuan West Road

Haidian District

Beijing, 100193, China

December 7st, 2023

Dear Editor,

Subject: Revised Manuscript Submission- The Diversity and Community Pattern of Liverworts in Sygera Mountain, Tibet

Manuscript ID: forests-2706819

I am writing to resubmit the revised version of our manuscript entitled “The Diversity and Community Pattern of Liverworts in Sygera Mountain, Tibet” for consideration for publication in forests. This manuscript was previously submitted on October 26, 2023, and received valuable feedback from the peer reviewers.

We sincerely appreciate the valuable comments and suggestions provided by you and the reviewers. Your insightful comments are invaluable in improving the quality of our manuscript. We have carefully read and actively responded to each comment. So, we revised the manuscript, including Figure 4, AppendixS1, and sentences, etc. Below are the specific revisions we made in response to the reviewers' feedback:

1. Since you explicitly refer to elevation and aspect, I would like these variables to be discriminated in the Excel file with supplementary material. One way of doing it would be to include two columns per elevation, one regarding the number of collections made in the East, and the West, respectively. Another way of promoting your data would be to share them as GBIF dataset (https://www.gbif.org/dataset/search).

Response: Thank you for your advice. We added it in Appendix S1 to show the species richness in different aspect directions and elevations. Please see the revised AppendixS1.

2. I believe that Figure 4 B is not well presented. The xx axis is off and the top whiskers of the boxplots are not visible.

Response: Thank you for your comments. Based on your suggestions, we have redrawn Figure 4. Please check Figure 4.

We hope you find the revised manuscript satisfactory. Thank you for considering our work and for the opportunity to revise and resubmit.

Truly yours

Xiaoming Shao

Reviewer 2 Report

With the supplementary list of species and the information that they are deposited in a public herbarium is mainly what I wanted added. Thanks.

In English, when a noun is used as an adjective, it is always in the singular. Thus, it is liverwort diversity, NOT liverworts diversity. 

Author Response

Xiaoming SHAO

Department of Ecology and Ecological Engineering

College of Resources and Environmental Sciences

China Agricultural University

No.2 Yuanmingyuan West Road

Haidian District

Beijing, 100193, China

December 7st, 2023

Dear Editor,

Subject: Revised Manuscript Submission- The Diversity and Community Pattern of Liverworts in Sygera Mountain, Tibet

Manuscript ID: forests-2706819

I am writing to resubmit the revised version of our manuscript entitled “The Diversity and Community Pattern of Liverworts in Sygera Mountain, Tibet” for consideration for publication in forests. This manuscript was previously submitted on October 26, 2023, and received valuable feedback from the peer reviewers.

We sincerely appreciate the valuable comments and suggestions provided by you and the reviewers. Your insightful comments are invaluable in improving the quality of our manuscript. We have carefully read and actively responded to each comment. So, we revised the manuscript, including Figure 4, AppendixS1, and sentences, etc. Below are the specific revisions we made in response to the reviewers' feedback:

1.With the supplementary list of species and the information that they are deposited in a public herbarium is mainly what I wanted added. Thanks.

Response: Thank you for your advice. We added it in Appendix S1 to show the species list and richness in different aspect and elevations. Please see the revised AppendixS1. All procured specimens have been archived at the Herbarium of China Agricultural University (BAU) for future study.

2. In English, when a noun is used as an adjective, it is always in the singular. Thus, it is liverwort diversity, NOT liverworts diversity. 

Response: Thank you for your correction. We have corrected into liverwort diversity.

We hope you find the revised manuscript satisfactory. We hope you find the revised manuscript satisfactory. Thank you for considering our work and for the opportunity to revise and resubmit.

Truly yours

Xiaoming Shao