Observed and Predicted Geographic Distribution of Acer monspessulanum L. Using the MaxEnt Model in the Context of Climate Change

Round 1

Reviewer 1 Report

 “Observed and projected geographic potential distribution of a Mediterranean native species (Acer monspessulanum L.) using the MaxEnt model in the changing climate context” by Hamdi Aouinti , Hassane Moutahir , Issam Touhami, Juan Bellot and Abdelhamid Khaldi

 Major comments.

I found a substantial and detailed work that the authors have done and obtained interesting results for this native tree species (Acer monspessulanum L.) distributions across the Mediterranean countries in current and future climates. The manuscript was nicely designed and fulfilled.

After the article “Maximum entropy modeling of species geographic distributions. Ecological Modeling” by Steven J. Phillips, Robert P. Anderson and Robert E. Schapire Vol 190/3-4 pp 231-259” was published in 2006 many publications appeared since then that used the MaxEnt approach to model plants distributions in various geographic regions in contemporary and future climates.

However, I have principal comments for this manuscript to be revised and many issues to be solved. Any modeling instrument (complicated or uncomplicated) requires ecological insights to explain obtained results. The authors applied three types of variables to modeling Montpellier maple ranges in various environments: 1. – variables that may change by 2050-2080 (climatic); 2. – variables that will not change in time (topography: elevation, slopes, aspects); 3. – variables that will change in time but the authors assumed them to be constant (vegetation types like trees, shrubs and bareland).
            Elevation was found to be the second important variable regulating the maple distribution over the region. However, we know from climatology that topography (elevation, slope and aspect) just regulates climates and is essentially a proxy for climate. E.g. mean annual temperature lapse rate is on average 0.6° С / 100 м globally. Moreover, slopes and aspects play different roles at different elevations. E.g., at higher elevations south-facing slopes are warmer and are favorable for plants, while at lower elevations southern slopes are hot and dry that challenge plants occurrence and distribution. Thus, the authors used climate variables and duplicated them by topography variables. In the future, the elevation range of this maple will not remain the same as nowadays as the authors found to be 300-1800 m. because climates will warm and most likely the maple range will climb up over mountains and will shift northwards over plains. Additionally, because vegetation types also impact the maple range vegetation types distributions should be predicted first and then the maple range should be predicted within a vegetation type range. So, in Discussions the authors should explain what a specific role topography and vegetation types play for the maple distribution in future climates.  

The authors found that the maple range would lose >90% of its current status. However, many publications found that ranges of biomes, trees and plants as a whole would adapt to a warmer climate by migrating to new suitable habitats mostly climbing up mountains and shifting northwards on plains. Thus, please discuss why the Montpellier maple would lose the most range rather than shift to new climates in central and northern Europe.

I suggest the major revision of the manuscript with suggested comments.

Minor comments.
Keywords should not repeat the title.

Please check spelling and fix many misprints. There are just several examples.

Line 21.  ‘witness’ should be ‘wetness’ in Abstract and elsewhere

L. 146.  Please correct ‘where’ for ‘were’

L. 259. Please correct the mean value for BIO4

L. 339. Please correct ‘founded’ for ‘found’.   Etc.

 Please enlarge legends and axis labels in figures 7-10 for the reader to read.

Author Response

Dear Reviewer,

Before responding to your comments, we would like to thank you for your very useful referee report, which has undoubtedly contributed to the improvement of the article. We are very grateful for the time and effort that you have devoted to our paper and we expect that the revision made to the manuscript and our responses below address your concerns. Changes in the Manuscript were made using track change and we are ready to make any additional changes that you deem necessary.

Author Response File: Author Response.docx

Reviewer 2 Report

The present MS is trying to predict the potential distribution of Acer monspessulanum (Montpellier maple), proposed to let the plant under a climate change scenarios and MaxEnt model predict is used. The study is due for publication for the journal Forests and suggested for accept after a minor review.

 

1. "Acer monspessulanum" should be italic in the title. 

and more, all Latin name of species should italic. 

2. all sites in the MS, "km2" should be as km²

 

3. suggested to rewrite the title, to make it short and clear enough for the study itself. 

Author Response

Dear Reviewer,

Before responding to your comments, we would like to thank you for your very useful referee report, which has undoubtedly contributed to the improvement of the article. We are very grateful for the time and effort that you have devoted to our paper and we expect that the revision made to the manuscript and our responses below address your concerns. Changes in the Manuscript were made using track change and we are ready to make any additional changes that you deem necessary.

Author Response File: Author Response.docx

Reviewer 3 Report

Please find comments, corrections, and suggestions on the attachment file. 

Comments for author File: Comments.pdf

Author Response

Dear Reviewer,

Before responding to your comments, we would like to thank you for your very useful referee report, which has undoubtedly contributed to the improvement of the article. We are very grateful for the time and effort that you have devoted to our paper and we expect that the revision made to the manuscript and our responses below address your concerns. Changes in the Manuscript were made using track change and we are ready to make any additional changes that you deem necessary.

Author Response File: Author Response.docx

Round 2

Reviewer 1 Report

In my first review, I suggested for the authors to explain what specific role topography and vegetation types play for the Montpellier maple distribution in future climates.  

For predicting the Montpellier Maple range in a warmed future I suggested to use only bioclimatic drivers that change under climate warming and to exclude the elevation that does not change and misrepresent results in a changing climate. Yet, I suggested to discuss the differences between these two predictions: with and without the elevation driver in the future. I do not see results of such an analysis.

The authors replied to my comments in their cover letter but I do not see their explanations and arguments in the Discussion section. I see only grammar edits.

I am not convinced in results and conclusions regarding the future predictions therefore again I suggest adding more discussion how the elevation driver may change the maple range in the future.

Nevertheless, I give the authors degree of freedom and thus expect degree of responsibility. If other reviewers accept the paper I will not argue.

Let the Reader makes the final decision.