Planted or Natural Pine Forests, Which One Will Better Recover after Drought? Insights from Tree Growth and Stable C and H Isotopes

Round 1

Reviewer 1 Report

Dear Authors and Editor 

Below are some general and specific comments on the paper entitled “Planted or natural pine forests, which one will better recover after drought? Insights from tree growth and stable C and H isotopes”. (Manuscript Number: forests-2194515). 

This paper is interesting because it presents new data on tree growth and the stable isotopes to evaluate the impact of drought on planted or natural pine forests.  However, the manuscript is remarkably inadequate in several points and the following suggested changes may rectify this problem.

Overall comments:

1.     The number of stable isotopic data is so limited that the response to drought cannot be evaluated. 

2.     Figure 2 and Figure 3 are not consistent with the main text, I was confused to review this paper.

3.     In the section of discussion, there are no citation of the figures; thus the reader do not understand the content correctly.

4.     I think it would be better to present the map and the climograph of study area in the text, not as a supplement.

Specific comments:

l  Equation (4): A, g and s is not defined in this paper.

l  Figure 2: Is the use of “bule/red” words appropriate?  Figure 2 is not consistent with the text of line 305-314. 

l  Line 402-403: The title of 4.1 section is not appropriate, because the author do not discuss stable isotopes in the section.

l  Figure 3: Is the use of “planted/natural” words appropriate?  Figure 3 is not consistent with the text of line 431-444.

l  Figure 4: The number of stable isotopic data is limited…

Author Response

Manuscript ID: Forests-2194515

Title: “Planted or natural pine forests, which one will better recover after drought? Insights from tree growth and stable C and H isotopes”

Reviewer#1

General comments:

1. Below are some general and specific comments on the paper entitled “Planted or natural pine forests, which one will better recover after drought? Insights from tree growth and stable C and H isotopes”. (Manuscript Number: forests-2194515).

This paper is interesting because it presents new data on tree growth and the stable isotopes to evaluate the impact of drought on planted or natural pine forests.  However, the manuscript is remarkably inadequate in several points and the following suggested changes may rectify this problem.

We appreciate the reviewer’s comments, and we have tried to answer all the questions raised in the following paragraphs. All the specific suggestions have been included which have improved the quality of the manuscript.

2. The number of stable isotopic data is so limited that the response to drought cannot be evaluated.

We agree with the reviewer that the number of isotope samples is limited (N=48, 3 samples per treatment and measurement). However, we consider that it is sufficient to know the isotopic response of the treatments given the homogeneity of the results in each of them. On the other hand, the difficulty of obtaining the samples and the analytical cost have not allowed us to obtain a size of our largest. In previous works, the same extraction protocol has been followed, with the results being acceptable from the scientific point of view (see Navarro-Cerrillo et al., 2019).

Navarro-Cerrillo, R. M., Sánchez-Salguero, R., Rodriguez, C., Lazo, J. D., Moreno-Rojas, J. M., Palacios-Rodriguez, G., & Camarero, J. J. (2019). Is thinning an alternative when trees could die in response to drought? The case of planted Pinus nigra and P. Sylvestris stands in southern Spain. Forest Ecology and Management, 433, 313-324.

3. Figure 2 and Figure 3 are not consistent with the main text, I was confused to review this paper.

We appreciate the reviewer’s comments, and we have tried to improve the clarity of results related to Fig. 2 and 3. See specific comments #7 and #9.

4. In the section of discussion, there are no citation of the figures; thus, the reader do not understand the content correctly.

We thank the reviewer’s comment, we have thoroughly revised the discussion section to include the references to tables and figures in order to improve clarity.

5. I think it would be better to present the map and the climograph of study area in the text, not as a supplement.

We appreciate the reviewer's suggestion, but since another of the reviewers has asked to transfer the table with plot data to the manuscript, we thought that the information would be redundant, so we have chosen to include a new table (Table 1), with all the plot information.

 

 

Specific comments:

6. Equation (4): A, g and s is not defined in this paper.

We thank the reviewer’s comment, and the variables have been described.

L291-293.- A is the molar flux of CO₂ into the plant from the atmosphere and g is the conductance of the boundary layer and stomata1 pores to the diffusion of CO₂.

7. Figure 2: Is the use of “bule/red” words appropriate? Figure 2 is not consistent with the text of line 305-314.

We thank the reviewer’s comment, and the text has been reviewed according to his/her recommendation to improve clarity.

L318-326.- In P. pinaster, wet conditions in the prior summer and warmer conditions in the winter enhanced growth in natural forests (Fig. 2, Fig. S3 Supplementary Material). On the other hand, planted forests seemed to be less sensitive to climate, and tree growth benefited from precipitations in the previous October and current March. However, dry conditions in previous summer (July) and current autumn (September) had a negative effect on growth. In the case of P. nigra, growth positively correlated with April-May precipitation but negatively with temperature over May and July (Fig. 2, Fig. S3 Sup-plementary Material). Pinus nigra showed a negative to earlier spring (May) and sum-mer (July) temperatures.

8. Line 402-403: The title of 4.1 section is not appropriate, because the author do not discuss stable isotopes in the section.

We appreciate the reviewer´s comment, and the title of section 4.1. has been changed.

4.1. Growth patterns and responses to climate in planted and natural forests

9. Figure 3: Is the use of “planted/natural” words appropriate? Figure 3 is not consistent with the text of lines 431-444.
10. Figure 4: The number of stable isotopic data is limited…

See comment#2

Author Response File: Author Response.docx

Reviewer 2 Report

Minor comment:

1. The resolution of some figures (e.g. Figure 2 and Figure 4) are low, please improve it.

2. I suggest you make the tree-ring data used in the paper public available.

Author Response

Manuscript ID: Forests-2194515 “Planted or natural pine forests, which one will better recover after drought? Insights from tree growth and stable C and H isotopes”

Reviewer#2

Minor comment:

1. The resolution of some figures (e.g. Figure 2 and Figure 4) are low, please improve it.

We appreciate the reviewer's comment and Fig. 2 and Fig. 4 have been changed to improve clarity.

2. 2. I suggest you make the tree-ring data used in the paper public available.

We agree with the reviewer´s comment, and we are willing to share tree ring data with the scientific community; thus, we will offer those data thought public access.

 

Author Response File: Author Response.docx

Reviewer 3 Report

Dear Authors,

I have reviewed the paper " Planted or natural pine forests, which one will better recover after drought? Insights from tree growth and stable C and H isotopes ". The contribution of this paper to the scientific knowledge is moderate. The paper is written with a moderate English level.The aims of the paper are germane with Forests topic, but in my opinion, there some important flaws and I suggest the corrections in the comments for the authors  in the file attached.

 

 

 

Comments for author File: Comments.pdf

Author Response

Manuscript ID: Forests-2194515

Title: “Planted or natural pine forests, which one will better recover after drought? Insights from tree growth and stable C and H isotopes”

Reviewer#2

General comments:

1. I have reviewed the paper " Planted or natural pine forests, which one will better recover after drought? Insights from tree growth and stable C and H isotopes ". The contribution of this paper to the scientific knowledge is moderate. The aims of the paper are germane with Forests topic, but in my opinion, there some important flaws and I suggest the corrections in the comments for the authors in the file

We appreciate the comments from reviewer, and we have tried to answer all the questions raised in the following paragraphs. All the specific suggestions have been included which have improved the quality of the manuscript.

2. The paper is written with a moderate English level.

We appreciate the reviewer´s comment regarding English writing. The manuscript has been completely reviewed by a native English editor, Dra. Sally Newton, that University of Córdoba offers to their researchers. We believe the manuscript has improved the clarity and avoided the problems of understanding of the previous version. Also the recommendations of the two reviewers have greatly improved the clarity of the text, which we deeply appreciate.

3. 3. Table 1.- Sorry, but in my opinion, it is necessary also in the paper a synthetic table about the main denrometric and silvicultural features of these forests. Your supplementary material is good but in order to have a better understanding of the paper I brief table is necessary also in the main text with some considerations about.

We agree with the reviewer on the importance of including the main dendrometric and silvicultural features of the studied forests. A new table (Table 1) has been included.

4. Figure 3.- Please pay attention in some bar there are letters (also if the same "a"a") and in other bars the letters are missing. I suggest to correct. In the caption you write means ± standard error but in the bar only the value + is visible.

In Figure 3, we have avoided including the test letters when they were not significant in order to simplify the figure. The foot of the table has been modified to improve the clarity of the figure and the reference to the average values.

5. Figure 4.- Are these relationships so necessary? Without any statistical analysis I suggest to delete or reconsider them.

We appreciate the author's suggestion, but we consider that figure 4 is an important research result. It is true that there is no specific statistical analysis between both thinning treatments, but since it is a regression of the isotopic values, the derived statistics themselves show very important information. On the one hand, the positive or negative trend of each treatment, and on the other, the coefficient of determination and the statistical significance of the regression. Both types of information reveal a clearly different response between species and thinning treatments.

 

 

6. Figure 5.- please specify the meaning of the box limits and the bars.

We appreciate the reviewer´s comment regarding English writing and the meaning of the box limits and the bars have been included.

7. 4.4. Implications for forest management

We appreciate the reviewer´s suggestion, and we have improved the information included in this section. In the new wording, an attempt has been made to highlight the most innovative aspects of the research, and its practical application to management, which can be summarized in two aspects:

1. It is necessary to adapt forestry to each species, even when ecological needs are very similar (P. sylvestris vs P. nigra).
2. The application of a same thinning intensity for all species can have counterproductive effects for some of them.

These results come to confirm what we have already observed in previous works in pine plantations in Mediterranean mountain areas.

Author Response File: Author Response.docx

Round 2

Reviewer 3 Report

Dear Authors, with the changes made the paper has been improved