Review Reports - Tree Rings of <i>Pinus greggii</i> Engelm. as Biomonitoring Proxies of Urban Heavy Metal Pollution in the Mexico City Metropolitan Area

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

In 3 parks (SJA, GUAD and COY) samples of two increment cores of Pinus greggii were extracted. One core was taken at the base of the tree, and the other at breast height. In total 60 increment cores were collected. Cross dating and ring width measurements were conducted following standard dendrochronological techniques. 14 cores for SJA, 10 cores for the GUAD site, and 10 cores plus two cross-sections for COY were successfully dated. The ring width index (RWI) was calculated.

Climate data from each station were averaged to construct a site specific dataset and subsequently associated with the RWI.

Metal analysis was conducted for each annual tree ring, focusing on the period 2002 to 2022 with four trees per site. The concentrations of Fe, Cu, Zn, and Pb in the material were determined using X ray fluorescence analysis.

For elements’ concentration comparison between sites ANOVA analysis was used. To evaluate changes in metal concentrations a temporal trend analysis was performed using the nonparametric Theil–Sen estimator.

The pollution concentration maps were derived from atmospheric monitoring data and spatial predictors as described in the cited article.

In Results section dendrochronological information was discussed. Several intervals of low growth were identified in the sites but occurring during different periods. Differences can be assigned to effect of climatic variables.

Results of heavy metal accumulation in tree rings investigation were presented. Temporal trends in the concentrations of Fe, Cu, Zn, and Pb in tree rings and their relationship to atmospheric pollutants were discussed.

Correlation of Cu, Fe, Pb, and Zn in tree rings with atmospheric pollutants was studied. The data analysis included estimation of lag influence on correlation. The results were different for the sites studied.

Comments

I. In lines 105-110 aims of the study were formulated. In comparison with the next sections content the aims are presented in a superficial way. Instead of “… the objective of this study was to analyze inter-annual trends in radial growth and heavy metal accumulation, as well as the relationship of these temporal trends with atmospheric pollutant levels...” it would be better to divide the sentence in separate bullets, for example (proposition, change if desired):

The objective of this study was:

1. Comparison of inter-annual trends in radial growth in Pinus greggii growing at SJA, GUAD and COY parks.

2. Comparison of Fe, Cu, Zn, and Pb concentration in Pinus greggii trunk from the studied parks.

3. Evaluation of changes in metal concentrations in tree rings from the studied parks.

4. Evaluation of relationships between the metal concentration in tree rings and NOx, O₃, PM₂.₅, and PM₁₀ levels in atmosphere.

In section Conclusions the research results should be presented with reference to aims of the study.

II. The samples were collected from 2 levels, BA and DBH. Were the results significantly different?

III. Explain abbreviation NS in Tab. 5.

Author Response

We sincerely thank the reviewers for their thorough evaluation of our manuscript and for their insightful and constructive comments. These suggestions have been invaluable in improving the quality and clarity of our work. We have carefully revised the manuscript in accordance with all the comments provided.

Reviewer 1

In lines 105-110 aims of the study were formulated. In comparison with the next sections content the aims are presented in a superficial way. Instead of “… the objective of this study was to analyze inter-annual trends in radial growth and heavy metal accumulation, as well as the relationship of these temporal trends with atmospheric pollutant levels...” it would be better to divide the sentence in separate bullets, for example (proposition, change if desired):

The objective of this study was:

Comparison of inter-annual trends in radial growth in Pinus greggii growing at SJA, GUAD and COY parks.
Comparison of Fe, Cu, Zn, and Pb concentration in Pinus greggii trunk from the studied parks.
Evaluation of changes in metal concentrations in tree rings from the studied parks.
Evaluation of relationships between the metal concentration in tree rings and NOx, O₃, PM₂.₅, and PM₁₀ levels in atmosphere.

Thank you for your advice. We have rewritten the objectives to improve clarity (L111:116)

In section Conclusions the research results should be presented with reference to aims of the study.

Thank you for pointing this out. We have carefully revised the Conclusion.

The samples were collected from 2 levels, BA and DBH. Were the results significantly different?

Thank you for this comment. In this study, due to time and budgets constrains, only samples collected at DBH (1.30 m) were analyzed. Therefore, no comparison between BA and DBH levels was performed, and it is not possible to determine whether the results differed significantly between these sampling heights. This clarification has been added to the revised manuscript (L151:152).

Explain abbreviation NS in Tab. 5.

Thank you for this comment. The abbreviation NS has been added to the table footnote and defined as “not significant.”

Reviewer 2 Report

Comments and Suggestions for Authors

Comments for Authors:

The manuscript titled “Tree Rings of Pinus greggii Engelm. as Biomonitoring Proxies of Urban Heavy Metal Pollution in the Mexico City Metropolitan Area” presents an interesting and relevant study that integrates dendrochronology and environmental chemistry to assess urban pollution dynamics. The use of tree-ring dendrochemistry combined with atmospheric pollutant data provides a valuable long-term perspective on environmental monitoring. The study is timely and contributes to the growing field of biomonitoring in urban ecosystems. However, several aspects of clarity, methodology description, and language require improvement before the manuscript can be considered for publication.

Specific comments:

Lines 25–27. The statement regarding peak concentrations (e.g., Fe, Cu, Zn in “GGAD”) lacks clarity and consistency. The site abbreviation “GGAD” appears inconsistent with “GUAD” used earlier.
Lines 33–34. The phrase “and and evidence-based management” indicates redundancy and disrupts the flow of the concluding sentence.
Briefly include statistical methods (e.g., type of correlation, software, lag analysis approach) to improve reproducibility. (Abstract)
Ensure all site abbreviations (SJA, GUAD, COY) are used consistently throughout the abstract/Manuscript.
The final sentence could be made more impactful by clearly stating the broader implications for urban environmental policy or management.
Line 20. What specific statistical method was used to assess correlations (e.g., Pearson, Spearman)?
Line 21. with with atmospheric pollutant concentrations; repetition of with
Line 33–34. and and evidence-based management; repeated and
Lines 85–86. The phrase “environmental influences and environmental influences” is repeated unnecessarily, affecting readability.
Lines 108–109. The hypothesis could be more specific by indicating expected relationships (e.g., positive correlations between specific metals and pollutants or spatial gradients).
Line 85–86. environmental influences and environmental influences; repetition error.
Lines 262–266, 336–347. Interpretations such as drought explanations and physiological mechanisms (e.g., nutrient accumulation near the cambium) should be moved to the Discussion section. The Results should primarily present findings.
Lines 326–330. The reporting of statistical differences is unclear and inconsistent (e.g., mixing p < 0.05 and p < 0.02 without explanation). A consistent format and clearer comparisons are needed.
Lines 272–293, 382–435. Some paragraphs are excessively long and contain multiple ideas (climate effects, mechanisms, comparisons), making them difficult to follow. These should be broken into shorter, focused paragraphs.
Ensure consistent formatting of pollutants (e.g., NOx vs NOX, PM2.5 vs PM₂.₅) and statistical notation throughout the section.
Line 247. environmental variations this site” should be “environmental variations at this site”.
Line 355: “2011.However” missing space; should be “2011. However”
Many grammatical and language mistakes should be improved.
Please avoid symbols at the beginning of sentences.
Please arrange all the references according to the Journal format.

Author Response

Reviewer 2

Lines 25–27. The statement regarding peak concentrations (e.g., Fe, Cu, Zn in “GGAD”) lacks clarity and consistency. The site abbreviation “GGAD” appears inconsistent with “GUAD” used earlier.

Thank you for your observation. The inconsistency in the site abbreviation has been corrected. Additionally, the sentence has been revised to improve clarity (L27:30)

Lines 33–34. The phrase “and and evidence-based management” indicates redundancy and disrupts the flow of the concluding sentence.

Thank you for your observation. The sentence has been revised to improve its clarity (L35:L38)

Briefly include statistical methods (e.g., type of correlation, software, lag analysis approach) to improve reproducibility. (Abstract)

Thank you for the suggestion. A brief description of the statistical methods has been incorporated into the abstract (L25:26).

Ensure all site abbreviations (SJA, GUAD, COY) are used consistently throughout the abstract/Manuscript.

Thank you for your observation. The manuscript has been revised to ensure consistent use of all site abbreviations (SJA, GUAD, and COY) throughout the abstract and the full text.

The final sentence could be made more impactful by clearly stating the broader implications for urban environmental policy or management.

Thank you for the suggestion. The final sentence has been revised to more clearly highlight its broader implications for urban environmental policy formulation (L34:38)

Line 20. What specific statistical method was used to assess correlations (e.g., Pearson, Spearman)?

Thank you for your observation. It has been specified that the statistical method used to evaluate the correlation was the Pearson correlation coefficient (L26).

Line 21. with with atmospheric pollutant concentrations; repetition of with

Thank you for your observation (L21)

Line 33–34. and and evidence-based management; repeated and

We appreciate your observation regarding (L37)

Lines 85–86. The phrase “environmental influences and environmental influences” is repeated unnecessarily, affecting readability.

Thank you for your observation. The sentence has been corrected (L91).

Lines 108–109. The hypothesis could be more specific by indicating expected relationships (e.g., positive correlations between specific metals and pollutants or spatial gradients).

Thank you for the suggestion. The hypotheses have been reformulated to make them more specific and better aligned with the objectives.

Lines 262–266, 336–347. Interpretations such as drought explanations and physiological mechanisms (e.g., nutrient accumulation near the cambium) should be moved to the Discussion section. The Results should primarily present findings.

Thank you for your observation. It is clarified that this section corresponds to combined Results and Discussion.

Lines 326–330. The reporting of statistical differences is unclear and inconsistent (e.g., mixing p < 0.05 and p < 0.02 without explanation). A consistent format and clearer comparisons are needed.

Thank you for the point. The wording has been revised to present the comparisons more clearly and consistently, and the significance criteria have been unified (L335:342, Table 4).

Lines 272–293, 382–435. Some paragraphs are excessively long and contain multiple ideas (climate effects, mechanisms, comparisons), making them difficult to follow. These should be broken into shorter, focused paragraphs.

We appreciate the reviewer’s comment. In response, we have restructured the sentecens, dividing them into shorter, clearer paragraphs.

Ensure consistent formatting of pollutants (e.g., NOx vs NOX, PM2.5 vs PM₂.₅) and statistical notation throughout the section.

We appreciate the reviewer’s comment. We have carefully revised the entire section to ensure consistency in the notation of pollutants.

Line 247. environmental variations this site” should be “environmental variations at this site”.

We appreciate the reviewer’s comment. We have rewritte the full sentence.

Line 355: “2011.However” missing space; should be “2011. However”

We appreciate the reviewer’s observation. The typo has been corrected.

Many grammatical and language mistakes should be improved.

We appreciate the reviewer’s comment. We have conducted a thorough revision of the manuscript to correct grammatical errors and clarity.

Please avoid symbols at the beginning of sentences.

We appreciate the reviewer’s observation. We have carefully revised the manuscript and corrected the use of symbols at the beginning of sentences, ensuring that all sentences start appropriately and improving the overall clarity and presentation of the text.

Please arrange all the references according to the Journal format.

We appreciate the reviewer’s observation. We have reviewed and reorganized all references to ensure they comply with the journal’s required format, including citation style.

Reviewer 3 Report

Comments and Suggestions for Authors

This study aimed to compare the iron, copper, zinc, and lead contents in tree rings of Pinus greggii. Wood samples were collected from plants growing in three Mexico City parks, differing in growing conditions and levels of anthropogenic pressure. Tree ring chemical elements were analyzed at annual resolution for the period from 2002 to 2022, and their relationships with atmospheric pollutant concentrations, including nitrogen oxides, carbon monoxide, ozone, and particulate matter, were assessed using a spatial scaling approach. Quantification of chemical elements was performed using X-ray fluorescence. Overall, the methods are described in sufficient detail and are appropriate for the objectives. The authors demonstrated the sensitivity of Pinus greggii to urban atmospheric pollution and support its potential as a biomonitoring tool for long-term environmental assessment and evidence-based management of urban green spaces, which is important for the further practical application of the obtained results. The following comments arose during the analysis of the manuscript:

It remains unclear why the authors limited their analysis to only four metals and what determined their choice of iron, copper, zinc, and lead. If the goal of the study was to "analyze interannual trends in radial growth and heavy metal accumulation, as well as the relationship of these temporal trends with atmospheric pollutant levels," then choosing a broader range of elements seems logical, especially since the authors have the resources to do so. Was the study limited to these metals because they are the major pollutants in the region? Are there any data on that?
There are numerous studies on the dendrochemical analysis of tree rings, many of which are cited by the authors. Therefore, it is necessary to more clearly articulate the novelty of this study.
The primary objective of the manuscript is to study the metal content in Pinus greggii wood growing in different parks in Mexico City. Metal content in plants depends on their concentrations in the environment. It is likely to be expected that the content of the studied metals in the soil varies across parks in Mexico City. However, such data are missing from the soil characterization. It would be desirable to provide the data on the metal contents in the soils of the studied areas, at least to date, to allow for a comparative assessment of these areas.
A shortcoming of this manuscript is the lack of a separate "Discussion" section. Some elements of the discussion are present in the "Results" section.
The authors write that "Lead (Pb), in turn, showed a slight decrease at SJA, GUAD, and COY starting in 2010." However, it remains unclear whether these changes are reliable, for example, in the case of COY, for which there was a high peak in lead content in 2016. The text of the manuscript should be checked for more accurate compliance with the experimental data in the figures.
All abbreviations should be expanded upon first mention in the main text of the article. It is necessary to indicate the differences between PM₂.₅ and PM₁₀.
The manuscript requires stylistic and lexical editing. There are multiple misprints and text duplications in the manuscript (e.g. «with with» on line 21, «GGAD» on line 27, «and and» on line 34, «GUA» on line 249, etc.). Does NOX (line 269) mean NO_X? The text of the manuscript needs a thorough check for the misprints, word duplications and inconsistencies.

Author Response

Reviewer 3

It remains unclear why the authors limited their analysis to only four metals and what determined their choice of iron, copper, zinc, and lead. If the goal of the study was to "analyze interannual trends in radial growth and heavy metal accumulation, as well as the relationship of these temporal trends with atmospheric pollutant levels," then choosing a broader range of elements seems logical, especially since the authors have the resources to do so. Was the study limited to these metals because they are the major pollutants in the region? Are there any data on that?

We appreciate the reviewer’s comment regarding the selection of metals. The choice of Fe, Cu, Zn, and Pb was based on their environmental relevance and their documented association with urban pollution sources in the Mexico City Metropolitan Area. Several studies and air quality reports in the region have identified these elements as common components of atmospheric particulate matter, primarily derived from vehicular emissions, industrial activities, and the resuspension of urban dust. In particular, Pb is widely recognized as a tracer of anthropogenic contamination, while Cu and Zn are associated with traffic-related sources such as brake and tire wear. Fe, although partly of geogenic origin, is also abundant in urban particles and reflects both natural and anthropogenic inputs. Additionally, these elements were selected due to their detectability and reliability in dendrochemical analyses using X-ray fluorescence, as well as their relatively stable incorporation into tree rings, which enables temporal assessments. While we acknowledge that including a broader range of elements could provide additional insights, the selected metals represent key indicators of urban pollution in the study area and allow for a robust evaluation of the relationship between atmospheric pollution and tree-ring chemistry.

There are numerous studies on the dendrochemical analysis of tree rings, many of which are cited by the authors. Therefore, it is necessary to more clearly articulate the novelty of this study.

We appreciate this observation. We acknowledge that numerous studies have been focused on dendrochemical analysis of tree rings; however, the novelty of this study lies in the multiapproach integrating dendrochronological, dendrochemical, and atmospheric pollution data within a highly complex urban context such as the Mexico City Metropolitan Area. Unlike previous studies, this work combines high-resolution temporal series (2002–2022) with a spatial scaling approach to evaluate the relationship between metal accumulation in tree rings and specific atmospheric pollutants (NOx, CO, O₃, PM₂.₅, and PM₁₀).

Furthermore, this study focuses on Pinus greggii, a species that has been scarcely studied for such applications in urban environments, providing evidence of its sensitivity and potential as a long-term biomonitoring tool. Finally, the comparison of sites with differing levels of anthropogenic pressure allows for the identification of spatial and temporal pollution patterns, contributing to a better understanding of urban environmental dynamics. This contribution has been clarified in the revised version of the manuscript.

The primary objective of the manuscript is to study the metal content in Pinus greggii wood growing in different parks in Mexico City. Metal content in plants depends on their concentrations in the environment. It is likely to be expected that the content of the studied metals in the soil varies across parks in Mexico City. However, such data are missing from the soil characterization. It would be desirable to provide the data on the metal contents in the soils of the studied areas, at least to date, to allow for a comparative assessment of these areas.

We sincerely appreciate the reviewer’s comment. We recognize the importance of including information on metal concentrations in soils to complement the interpretation of our results.

However, the primary objective of this study was to evaluate metal content in the tree rings of Pinus greggii as bioindicators of environmental pollution; therefore, soil analyses were not performed. Nevertheless, it is important to note that our previous research; Cruz-Huerta et al. (2025) analyzed soil, root, and foliage components at the same parks, providing relevant complementary information on metal dynamics within the soil–plant system. This reference and clarification have been incorporated into the manuscript to strengthen the discussion and better contextualize our findings.

A shortcoming of this manuscript is the lack of a separate "Discussion" section. Some elements of the discussion are present in the "Results" section.

We appreciate this valuable comment. However, we chose to structure the manuscript with Results and Discussion combined into a single section, which is editorially acceptable according to the journal guidelines (https://www.mdpi.com/journal/forests/instructions#template

). Furthermore, this decision was made to improve clarity and interpretability for the reader.

The authors write that "Lead (Pb), in turn, showed a slight decrease at SJA, GUAD, and COY starting in 2010." However, it remains unclear whether these changes are reliable, for example, in the case of COY, for which there was a high peak in lead content in 2016. The text of the manuscript should be checked for more accurate compliance with the experimental data in the figures.

Thank you for your careful review. We have revised this paragraph to improve its clarity (L361:372)

All abbreviations should be expanded upon first mention in the main text of the article. It is necessary to indicate the differences between PM₂. ₅ and PM₁₀.

We thank the reviewer for this comment. The manuscript has been carefully revised to ensure that all abbreviations are defined at their first mention in the main text. Furthermore, we have clarified the differences between PM₂.₅ and PM₁₀, focusing on particle size, and sources to enhance reader comprehension (L22:23)

The manuscript requires stylistic and lexical editing. There are multiple misprints and text duplications in the manuscript (e.g. «with with» on line 21, «GGAD» on line 27, «and and» on line 34, «GUA» on line 249, etc.). Does NOX (line 269) mean NO_X? The text of the manuscript needs a thorough check for the misprints, word duplications and inconsistencies.

We thank the reviewer for this comment. We have carried out a comprehensive revision of the manuscript.”

Reviewer 4 Report

Comments and Suggestions for Authors

Comments to the Author:

Title: Tree Rings of Pinus greggii Engelm. as Biomonitoring Proxies of Urban Heavy Metal Pollution in the Mexico City Metropolitan Area

Overview and general recommendation:

The manuscript deals with an important topic related to the role of tree rings of Pinus greggii Engelm. as biomonitoring proxies of urban heavy metal pollution in the Mexico city metropolitan area. The manuscript technically sounds well and shows high novelty. However, it needs major linguistic adjustments; therefore, I invite the authors to pass their manuscript to a native English speaker for editing and revision. In this regard, the needed adjustments are highlighted in “Minor comments” section. Also, numerous statements lack reliable sources (references) that should be provided.

The Abstract section outlines clearly the problematic, aims, methodology and findings of the current study while reporting the main conclusions aroused. However, authors shall mention some values of detected heavy metal concentrations and the strength of obtained correlations. The Introduction section is well structured and aiming and underlines appropriately the whole subject under study. However, are there any studies related to the topic in other world regions?? As to my knowledge, Pinus greggii Engelm. has been introduced to South Africa, South America, India, and Zimbabwe. If yes, authors shall mention them!! Moreover, more recent studies on the evaluation of heavy metals in tree rings are urged!! On the other hand, the aims of the study are also clear and understood. The Materials and Methods section is clear, well written, and encloses all the information related to the adopted methodology, and statistical analysis. The Results and Discussion section shows a correct statistical representation and an adequate scientific analysis of the findings. However, more recent studies shall be relied on to discuss the obtained findings. An appropriate Conclusions section was added in which authors summarized the findings of their study and suggested further related research being based on the raised assumptions.

My comments and queries for authors are detailed below in “Major comments” and “Minor comments” sections.

Major comments:

The manuscript needs major linguistic adjustments; accordingly, I invite the authors to pass their manuscript to a native English speaker for editing and revision. Most needed adjustments are highlighted in “Minor comments” section.
Abstract: Authors shall mention some values of detected heavy metal concentrations and the strength of obtained correlations.
Introduction: Are there any studies related to the topic in other world regions?? As to my knowledge, Pinus greggiiEngelm. has been introduced to South Africa, South America, India, and Zimbabwe. If yes, authors shall mention them.
Introduction: More recent studies on the evaluation of heavy metals in tree rings are urged!!
Results and Discussion: More recent studies shall be relied on to discuss the obtained findings.

Minor comments:

Abstract: Page 1, line 17: Kindly adjust as follow: “evaluated”.
Abstract: Page 1, line 21: Kindly remove the duplicated “with”.
Introduction: Page 2, lines 40-43: “The concentration… [1,2]”: The references used for this statement are old; accordingly, kindly replace them by more recent ones (last five years of publication).
Introduction: Page 2, line 48: Kindly adjust as follow: “suggested”.
Introduction: Page 2, lines 49-50: “However… needed”: Kindly reformulate the sentence in a more appropriate manner.
Introduction: Page 2, lines 52-54: “Biomonitoring… [3,7]”: Reference number 7 is old; accordingly, kindly replace it by a more recent one (last five years of publication).
Introduction: Page 2, lines 54-58: “Inorganic… [8]”: Same recommendation as in the previous comment.
Introduction: Page 2, lines 59-64: “For example… [10]”: Same recommendation as in the previous two comments.
Introduction: Page 2, lines 67-69: “Consequently… [11]”: Same recommendation as in the previous comments.
Introduction: Page 2, lines 69-72: “For example… [12,13]”: Same recommendation as in the previous comments regarding reference number 12.
Introduction: Page 2, line 77: Kindly adjust as follow: “indicated”.
Materials and Methods, 2.2. Annual tree-ring growth analysis: Page 5, lines 143-144: “In late… sites”: Kindly avoid the first voice form of the sentence and adopt the impersonal form instead.
Materials and Methods, 2.6. Dendrochemical analysis of tree rings: Page 6, line 209: Kindly adjust as follow: “described by Rousseau et al. [39]”.
Materials and Methods, 2.7. Statistical analysis of elements in tree rings: Page 7, line 233: Kindly adjust as follow; “reported by Cruz-Huerta et al. [21]”.
Results and Discussion: Page 7, line 239: Kindly adjust the title of this section as follow: “3. Results and Discussion”.
Results and Discussion, 3.1. Dendrochronological information: Page 7, lines 246-250: “Regarding… irrigation”: The sentence is a little bit long; accordingly, kindly reformulate in order to make it more concise, clearer, and more aiming.
Results and Discussion, 3.1. Dendrochronological information: Page 7, lines 250-252: “This behavior… widths”: The reference used for this statement is old; accordingly, kindly replace it by a more recent one (last five years of publication).
Results and Discussion, 3.2. Effect of climatic variables on Pinus greggiigrowth: Page 9, lines 276-278: “indicating… increment”: This statement lacks reliable sources (references); accordingly, kindly provide them.
Results and Discussion, 3.2. Effect of climatic variables on Pinus greggiigrowth: Page 9, lines 280-281: “potentially… conditions”: Same recommendation as in the previous comment.
Results and Discussion, 3.2. Effect of climatic variables on Pinus greggiigrowth: Page 9, line 283: Kindly replace “are” by “were”.
Results and Discussion, 3.2. Effect of climatic variables on Pinus greggiigrowth: Page 9, line 284: Kindly replace “is” by “was”.
Results and Discussion, 3.2. Effect of climatic variables on Pinus greggiigrowth: Page 9, line 288: Kindly replace ‘are” by “were” and adjust as follow; “showed”.
Results and Discussion, 3.2. Effect of climatic variables on Pinus greggiigrowth: Page 9, line 289: Kindly adjust as follow: “occurred”.
Results and Discussion, 3.2. Effect of climatic variables on Pinus greggiigrowth: Page 9, line 290: Kindly adjust as follow: “favored”.
Results and Discussion, 3.2. Effect of climatic variables on Pinus greggiigrowth: Page 9, line 292: Kindly adjust as follow: “promoted”.
Results and Discussion, 3.2. Effect of climatic variables on Pinus greggiigrowth: Page 9, line 294: Kindly replace “is” by “was”.
Results and Discussion, 3.2. Effect of climatic variables on Pinus greggiigrowth: Page 9, line 296: Kindly adjust as follow: “indicated”.
Results and Discussion, 3.2. Effect of climatic variables on Pinus greggiigrowth: Page 9, lines 296-297: “This is… temperature”: The references used for this statement are old; accordingly, kindly replace them by more recent ones (last five years of publication).
Results and Discussion, 3.3. Heavy metal accumulation in tree rings: Pages 10-11, lines 310-312: “For instance… [48]”: Kindly avoid the first voice form of the sentence and adopt the impersonal form instead.
Results and Discussion, 3.3. Heavy metal accumulation in tree rings: Page 11, line 313: Kindly adjust as follow: “exceeded”.
Results and Discussion, 3.3. Heavy metal accumulation in tree rings: Page 11, line 314: Kindly adjust as follow: “suggested”.
Results and Discussion, 3.3. Heavy metal accumulation in tree rings: Page 11, line 317: Kindly replace “are” by “were”.
Results and Discussion, 3.3. Heavy metal accumulation in tree rings: Page 11, lines 316-318: “Considering… [51,52]”: The first reference used for this statement is old; accordingly, kindly replace it by a more recent one (last five years of publication).
Results and Discussion, 3.4. Temporal trends in the concentrations of heavy metals Fe, Cu, Zn, and Pb in treerings and their relationship with atmospheric pollutants: Page 11, line 325: Kindly adjust as follow: “The analysis”.
Results and Discussion, 3.4. Temporal trends in the concentrations of heavy metals Fe, Cu, Zn, and Pb in treerings and their relationship with atmospheric pollutants: Page 11, line 335: Kindly adjust as follow: “showed”.
Results and Discussion, 3.4. Temporal trends in the concentrations of heavy metals Fe, Cu, Zn, and Pb in treerings and their relationship with atmospheric pollutants: Page 11, lines 337-339: “Higher… [53]”: The reference used for this statement is old; accordingly, kindly replace it by a more recent one (last five years of publication).
Results and Discussion, 3.4. Temporal trends in the concentrations of heavy metals Fe, Cu, Zn, and Pb in treerings and their relationship with atmospheric pollutants: Page 11, line 339: Kindly adjust as follow: “reported”.
Results and Discussion, 3.4. Temporal trends in the concentrations of heavy metals Fe, Cu, Zn, and Pb in treerings and their relationship with atmospheric pollutants: Page 12, lines 343-345: “which… [56]”: The reference used for this statement is old; accordingly, kindly replace it by a more recent one (last five years of publication).
Results and Discussion, 3.4. Temporal trends in the concentrations of heavy metals Fe, Cu, Zn, and Pb in treerings and their relationship with atmospheric pollutants: Page 12, lines 345-348: “Importantly… [55,56]”: Same recommendation as in the previous comment regarding reference number 56.
Results and Discussion, 3.4. Temporal trends in the concentrations of heavy metals Fe, Cu, Zn, and Pb in treerings and their relationship with atmospheric pollutants: Page 12, line 349: Kindly remove “in” afterr “starting”.
Results and Discussion, 3.4. Temporal trends in the concentrations of heavy metals Fe, Cu, Zn, and Pb in treerings and their relationship with atmospheric pollutants: Page 12, line 354: Kindly adjust as follow: “consistent with Morton-Bermea et al. [58]”.
Results and Discussion, 3.4. Temporal trends in the concentrations of heavy metals Fe, Cu, Zn, and Pb in treerings and their relationship with atmospheric pollutants: Page 13, line 367: Kindly adjust as follow: “showed”.
Results and Discussion, 3.5. Correlation of Cu, Fe, Pb, and Zn in tree rings with atmospheric pollutants: Page 14, line 385: Kindly adjust as follow: “showed”.
Results and Discussion, 3.5. Correlation of Cu, Fe, Pb, and Zn in tree rings with atmospheric pollutants: Page 15, line 386: Kindly adjust as follow: “exhibited” and “showed”.
Results and Discussion, 3.5. Correlation of Cu, Fe, Pb, and Zn in tree rings with atmospheric pollutants: Page 15, line 390: Kindly replace “are” by “were”.
Results and Discussion, 3.5. Correlation of Cu, Fe, Pb, and Zn in tree rings with atmospheric pollutants: Page 15, lines 394-397: “Acid… [63,64]”: Reference number 64 is old; accordingly, kindly replace it by a more recent one (last five years of publication).
Results and Discussion, 3.5. Correlation of Cu, Fe, Pb, and Zn in tree rings with atmospheric pollutants: Page 15, line 400: Kindly adjust as follow: “showed”.
Results and Discussion, 3.5. Correlation of Cu, Fe, Pb, and Zn in tree rings with atmospheric pollutants: Page 15, line 401: Kindly adjust as follow: “exhibited”.
Results and Discussion, 3.5. Correlation of Cu, Fe, Pb, and Zn in tree rings with atmospheric pollutants: Page 15, lines 405-406: Kindly replace “are” by “were”.
Results and Discussion, 3.5. Correlation of Cu, Fe, Pb, and Zn in tree rings with atmospheric pollutants: Page 15, lines 406-408: Kindly write this sentence in the past verbal tense form.
Results and Discussion, 3.5. Correlation of Cu, Fe, Pb, and Zn in tree rings with atmospheric pollutants: Page 15, line 413: Kindly adjust as follow: “showed”.
Results and Discussion, 3.5. Correlation of Cu, Fe, Pb, and Zn in tree rings with atmospheric pollutants: Page 15, lines 415-416: Kindly adjust as follow: “displayed”.
Results and Discussion, 3.5. Correlation of Cu, Fe, Pb, and Zn in tree rings with atmospheric pollutants: Page 15, lines 418-420: “Ozone-induced… [65]”: The reference used for this statement is old; accordingly, kindly replace it by a more recent one (last five years of publication).
Results and Discussion, 3.5. Correlation of Cu, Fe, Pb, and Zn in tree rings with atmospheric pollutants: Page 15, line 421: Kindly adjust as follow: “exhibited”.
Results and Discussion, 3.5. Correlation of Cu, Fe, Pb, and Zn in tree rings with atmospheric pollutants: Page 15, line 422: Kindly adjust as follow: “showed”.
Results and Discussion, 3.5. Correlation of Cu, Fe, Pb, and Zn in tree rings with atmospheric pollutants: Page 15, lines 424-426: “Such… [66]”: The reference used for this statement is old; accordingly, kindly replace it by a more recent one (last five years of publication).
Results and Discussion, 3.5. Correlation of Cu, Fe, Pb, and Zn in tree rings with atmospheric pollutants: Page 15, line 430: Kindly replace “are” by “were”.
Results and Discussion, 3.5. Correlation of Cu, Fe, Pb, and Zn in tree rings with atmospheric pollutants: Page 15, line 432: Kindly adjust as follow: “showed”.

Comments on the Quality of English Language

The manuscript needs major linguistic adjustments; accordingly, I invite the authors to pass their manuscript to a native English speaker for editing and revision. Most needed adjustments are highlighted in “Minor comments” section within the attached report.

Author Response

Reviewer 4

Overview and general recommendation:

The manuscript deals with an important topic related to the role of tree rings of Pinus greggii Engelm. as biomonitoring proxies of urban heavy metal pollution in the Mexico city metropolitan area. The manuscript technically sounds well and shows high novelty. However, it needs major linguistic adjustments; therefore, I invite the authors to pass their manuscript to a native English speaker for editing and revision. In this regard, the needed adjustments are highlighted in “Minor comments” section. Also, numerous statements lack reliable sources (references) that should be provided.

The Abstract section outlines clearly the problematic, aims, methodology and findings of the current study while reporting the main conclusions aroused. However, authors shall mention some values of detected heavy metal concentrations and the strength of obtained correlations. The Introduction section is well structured and aiming and underlines appropriately the whole subject under study. However, are there any studies related to the topic in other world regions?? As to my knowledge, Pinus greggii Engelm. has been introduced to South Africa, South America, India, and Zimbabwe. If yes, authors shall mention them!! Moreover, more recent studies on the evaluation of heavy metals in tree rings are urged!! On the other hand, the aims of the study are also clear and understood. The Materials and Methods section is clear, well written, and encloses all the information related to the adopted methodology, and statistical analysis. The Results and Discussion section shows a correct statistical representation and an adequate scientific analysis of the findings. However, more recent studies shall be relied on to discuss the obtained findings. An appropriate Conclusions section was added in which authors summarized the findings of their study and suggested further related research being based on the raised assumptions.

Thank you for your feedback. We have carefully reviewed the manuscript to improve the English language.

Although research on tree rings and heavy metals has grown in recent decades, studies in megacities such as Mexico City remain limited. This study’s inclusion of three sites with different pollution levels and conditions further highlights its novelty.

Updated references have been included in this new version

Major comments:

Thank you for your feedback. We have carefully reviewed the manuscript to improve the English language.

Abstract: Authors shall mention some values of detected heavy metal concentrations and the strength of obtained correlations.

Thank you for your suggestion. The suggested values have been incorporated into the abstract (L29, L33).

Introduction: Are there any studies related to the topic in other world regions?? As to my knowledge, Pinus greggii Engelm. has been introduced to South Africa, South America, India, and Zimbabwe. If yes, authors shall mention them.

You are correct; Pinus greggii is a widely utilized species due to its capacity to grow in low-quality sites and its application in ecological restoration projects, among other uses. This information has been incorporated into the revised version L152:154

Introduction: More recent studies on the evaluation of heavy metals in tree rings are urged!!

We agree that the lack of studies, particularly in highly populated areas with contrasting conditions, makes it important to highlight the role of green areas as buffers or bioaccumulation systems.

Results and Discussion: More recent studies shall be relied on to discuss the obtained findings.

Thank you for your suggestion. We have incorporated updated references to strengthen the discussion

Minor comments:

Abstract: Page 1, line 17: Kindly adjust as follow: “evaluated”.

Your comment has been addressed.

Abstract: Page 1, line 21: Kindly remove the duplicated “with”.

Your comment has been addressed.

Introduction: Page 2, lines 40-43: “The concentration… [1,2]”: The references used for this statement are old; accordingly, kindly replace them by more recent ones (last five years of publication).

We thank the reviewer for this observation. The original references have been replaced with more recent ones

Sidor, C.G.; Cuciurean, C.I.; Camarero, J.J.; Badea, O. Heavy metal concentrations in deciduous tree rings reflects changes in temporal dynamic of industrial air pollution. Atmospheric Pollution Research 2026, 17, 102716, doi:https://doi.org/10.1016/j.apr.2025.102716.

Tang, S.; Wang, C.; Song, J.; Ihenetu, S.C.; Li, G. Advances in Studies on Heavy Metals in Urban Soil: A Bibliometric Analysis. Sustainability 2024, 16, 860.

Introduction: Page 2, line 48: Kindly adjust as follow: “suggested”.

Your comment has been addressed. L51

Introduction: Page 2, lines 49-50: “However… needed”: Kindly reformulate the sentence in a more appropriate manner.

We thank the reviewer for this observation. The sentence has been revised for clarity.

Introduction: Page 2, lines 52-54: “Biomonitoring… [3,7]”: Reference number 7 is old; accordingly, kindly replace it by a more recent one (last five years of publication).

We thank the reviewer for this observation. The original reference has been updated

Monaci, F.; Baroni, D. Leaves and Tree Rings as Biomonitoring Archives of Atmospheric Mercury Deposition: An Ecophysiological Perspective. Plants 2025, 14, 1275.

Introduction: Page 2, lines 54-58: “Inorganic… [8]”: Same recommendation as in the previous comment.

We thank the reviewer for this observation. The original reference has been updated

Binda, G.; Di Iorio, A.; Monticelli, D. The what, how, why, and when of dendrochemistry: (paleo)environmental information from the chemical analysis of tree rings. Sci Total Environ 2021, 758, 143672, doi:10.1016/j.scitotenv.2020.143672.

Introduction: Page 2, lines 59-64: “For example… [10]”: Same recommendation as in the previous two comments.

We thank the reviewer for this observation. The original reference has been retained, as it remains relevant (2015)

Introduction: Page 2, lines 67-69: “Consequently… [11]”: Same recommendation as in the previous comments.

We thank the reviewer for this observation. The original reference has been updated.

Canning, C.M.; Laroque, C.P.; Muir, D. Critical Analysis of the Past, Present, and Future of Dendrochemistry: A Systematic Literature Review. Forests 2023, 14, 1997.

Introduction: Page 2, lines 69-72: “For example… [12,13]”: Same recommendation as in the previous comments regarding reference number 12.

We thank the reviewer for this observation. The original reference has been updated

Cuciurean, C.I.; Sidor, C.G.; Camarero, J.J.; Buculei, A.; Badea, O. Detecting changes in industrial pollution by analyzing heavy metal concentrations in tree-ring wood from Romanian conifer forests. Environ Res 2024, 252, 118884, doi:10.1016/j.envres.2024.118884.

Introduction: Page 2, line 77: Kindly adjust as follow: “indicated”.

Your comment has been addressed. L82

Materials and Methods, 2.2. Annual tree-ring growth analysis: Page 5, lines 143-144: “In late… sites”: Kindly avoid the first voice form of the sentence and adopt the impersonal form instead.

We thank the reviewer for this observation. The sentence has been revised.

Materials and Methods, 2.6. Dendrochemical analysis of tree rings: Page 6, line 209: Kindly adjust as follow: “described by Rousseau et al. [39]”.

We thank the reviewer for this observation. The sentence has been revised. L218

Materials and Methods, 2.7. Statistical analysis of elements in tree rings: Page 7, line 233: Kindly adjust as follow; “reported by Cruz-Huerta et al. [21]”.

We thank the reviewer for this observation. The sentence has been revised. L242

Results and Discussion: Page 7, line 239: Kindly adjust the title of this section as follow: “3. Results and Discussion”.

We thank the reviewer for this observation. The title has been updated. L248

Results and Discussion, 3.1. Dendrochronological information: Page 7, lines 246-“Regarding… irrigation”: The sentence is a little bit long; accordingly, kindly reformulate in order to make it more concise, clearer, and more aiming.

We thank the reviewer for this observation. The sentence has been revised. L255:259

Results and Discussion, 3.1. Dendrochronological information: Page 7, lines 250-252: “This behavior… widths”: The reference used for this statement is old; accordingly, kindly replace it by a more recent one (last five years of publication).

We thank the reviewer for this observation. The original reference has been retained, as it remains relevant (2014)

Results and Discussion, 3.2. Effect of climatic variables on Pinus greggii growth: Page 9, lines 276-278: “indicating… increment”: This statement lacks reliable sources (references); accordingly, kindly provide them.

We thank the reviewer for this valuable comment. The sentence has been revised to include a reference supporting the information. L288:L290

Results and Discussion, 3.2. Effect of climatic variables on Pinus greggiigrowth: Page 9, lines 280-281: “potentially… conditions”: Same recommendation as in the previous comment.

We thank the reviewer for this valuable comment. The sentence has been revised to include a reference supporting the information. L293:L295

Results and Discussion, 3.2. Effect of climatic variables on Pinus greggiigrowth: Page 9, line 283: Kindly replace “are” by “were”.

Your comment has been addressed. L296

Results and Discussion, 3.2. Effect of climatic variables on Pinus greggiigrowth: Page 9, line 284: Kindly replace “is” by “was”.

We have addressed this point in the revised version. L297

Results and Discussion, 3.2. Effect of climatic variables on Pinus greggiigrowth: Page 9, line 288: Kindly replace ‘are” by “were” and adjust as follow; “showed”.

We have revised the manuscript to address this comment.. L301

Results and Discussion, 3.2. Effect of climatic variables on Pinus greggiigrowth: Page 9, line 289: Kindly adjust as follow: “occurred”.

Your comment has been addressed. L302

Results and Discussion, 3.2. Effect of climatic variables on Pinus greggiigrowth: Page 9, line 290: Kindly adjust as follow: “favored”.

We have incorporated changes to address this point.. L302

Results and Discussion, 3.2. Effect of climatic variables on Pinus greggiigrowth: Page 9, line 292: Kindly adjust as follow: “promoted”.

Your comment has been addressed. L305

Results and Discussion, 3.2. Effect of climatic variables on Pinus greggiigrowth: Page 9, line 294: Kindly replace “is” by “was”.

This comment has been addressed accordingly. L307

Results and Discussion, 3.2. Effect of climatic variables on Pinus greggiigrowth: Page 9, line 296: Kindly adjust as follow: “indicated”.

Your comment has been addressed. L309

Results and Discussion, 3.2. Effect of climatic variables on Pinus greggiigrowth: Page 9, lines 296-297: “This is… temperature”: The references used for this statement are old; accordingly, kindly replace them by more recent ones (last five years of publication).

We thank the reviewer for this observation. The references have been updated. L309

Results and Discussion, 3.3. Heavy metal accumulation in tree rings: Pages 10-11, lines 310-312: “For instance… [48]”: Kindly avoid the first voice form of the sentence and adopt the impersonal form instead.

We thank the reviewer for this observation. The sentence has been revised. L323:324

Results and Discussion, 3.3. Heavy metal accumulation in tree rings: Page 11, line 313: Kindly adjust as follow: “exceeded”.

Your comment has been addressed. L326

Results and Discussion, 3.3. Heavy metal accumulation in tree rings: Page 11, line 314: Kindly adjust as follow: “suggested”.

The issue has been addressed in the revised manuscript. L327

Results and Discussion, 3.3. Heavy metal accumulation in tree rings: Page 11, line 317: Kindly replace “are” by “were”.

Your comment has been addressed. L329

Results and Discussion, 3.3. Heavy metal accumulation in tree rings: Page 11, lines316-318: “Considering… [51,52]”: The first reference used for this statement is old; accordingly, kindly replace it by a more recent one (last five years of publication).

We thank the reviewer for this observation. The references have been updated. L331

Your comment has been addressed. L338

Thank you for your comment. The sentence has been revised to improve clarity

Results and Discussion, 3.4. Temporal trends in the concentrations of heavy metals Fe, Cu, Zn, and Pb in treerings and their relationship with atmospheric pollutants: Page 11, lines 337-339: “Higher… [53]”: The reference used for this statement is old; accordingly, kindly replace it by a more recent one (last five years of publication).

We thank the reviewer for this observation. The references have been updated. L354

Results and Discussion, 3.4. Temporal trends in the concentrations of heavy metals Fe, Cu, Zn, and Pb in treerings and their relationship with atmospheric pollutants: Page 12, lines 343-345: “which… [56]”: The reference used for this statement is old; accordingly, kindly replace it by a more recent one (last five years of publication).

We thank the reviewer for this observation. The references have been updated. L361

Results and Discussion, 3.4. Temporal trends in the concentrations of heavy metals Fe, Cu, Zn, and Pb in treerings and their relationship with atmospheric pollutants:4 Page 12, lines 345-348: “Importantly… [55,56]”: Same recommendation as in the previous comment regarding reference number 56.

We thank the reviewer for this observation. The references have been updated. L364

Thank you for your comment. The sentence has been revised to improve clarity. L365:367

Results and Discussion, 3.4. Temporal trends in the concentrations of heavy metals Fe, Cu, Zn, and Pb in treerings and their relationship with atmospheric pollutants: Page 12, line 354: Kindly adjust as follow: “consistent with Morton-Bermea et al. [58]”.

Your comment has been addressed. L374

Results and Discussion, 3.4. Temporal trends in the concentrations of heavy metals Fe, Cu, Zn, and Pb in treerings and their relationship with atmospheric pollutants: Page 13, line 367: Kindly adjust as follow: “showed”.

We have addressed this point in the revised version. L385

Results and Discussion, 3.5. Correlation of Cu, Fe, Pb, and Zn in tree rings with atmospheric pollutants: Page 15, line 386: Kindly adjust as follow: “exhibited” and “showed”.

Your comment has been addressed. L404:405

Results and Discussion, 3.5. Correlation of Cu, Fe, Pb, and Zn in tree rings with atmospheric pollutants: Page 15, line 390: Kindly replace “are” by “were”.

This concern has been carefully addressed. L408

Results and Discussion, 3.5. Correlation of Cu, Fe, Pb, and Zn in tree rings with atmospheric pollutants: Page 15, lines 394-397: “Acid… [63,64]”: Reference number 64 is old; accordingly, kindly replace it by a more recent one (last five years of publication).

We thank the reviewer for this observation. The reference has been updated. L415

Results and Discussion, 3.5. Correlation of Cu, Fe, Pb, and Zn in tree rings with atmospheric pollutants: Page 15, line 400: Kindly adjust as follow: “showed”.

Your comment has been addressed. L419

Results and Discussion, 3.5. Correlation of Cu, Fe, Pb, and Zn in tree rings with atmospheric pollutants: Page 15, line 401: Kindly adjust as follow: “exhibited”.

We have revised the manuscript to address this comment. L420

Results and Discussion, 3.5. Correlation of Cu, Fe, Pb, and Zn in tree rings with atmospheric pollutants: Page 15, lines 405-406: Kindly replace “are” by “were”.

Your comment has been addressed. L424:425

Results and Discussion, 3.5. Correlation of Cu, Fe, Pb, and Zn in tree rings with atmospheric pollutants: Page 15, lines 406-408: Kindly write this sentence in the past verbal tense form.

The manuscript has been modified accordingly. L425:426

Results and Discussion, 3.5. Correlation of Cu, Fe, Pb, and Zn in tree rings with atmospheric pollutants: Page 15, line 413: Kindly adjust as follow: “showed”.

Your comment has been addressed. L426

Results and Discussion, 3.5. Correlation of Cu, Fe, Pb, and Zn in tree rings with atmospheric pollutants: Page 15, lines 415-416: Kindly adjust as follow: “displayed”.

We have incorporated changes to address this point. L435

Results and Discussion, 3.5. Correlation of Cu, Fe, Pb, and Zn in tree rings with atmospheric pollutants: Page 15, lines 418-420: “Ozone-induced… [65]”: The reference used for this statement is old; accordingly, kindly replace it by a more recent one (last five years of publication).

We thank the reviewer for this observation. The reference has been updated. L439

Results and Discussion, 3.5. Correlation of Cu, Fe, Pb, and Zn in tree rings with atmospheric pollutants: Page 15, line 421: Kindly adjust as follow: “exhibited”.

Your comment has been addressed. L440

Results and Discussion, 3.5. Correlation of Cu, Fe, Pb, and Zn in tree rings with atmospheric pollutants: Page 15, line 422: Kindly adjust as follow: “showed”.

This comment has been addressed accordingly. L441

Results and Discussion, 3.5. Correlation of Cu, Fe, Pb, and Zn in tree rings with atmospheric pollutants: Page 15, lines 424-426: “Such… [66]”: The reference used for this statement is old; accordingly, kindly replace it by a more recent one (last five years of publication).

We thank the reviewer for this observation. The reference has been updated. L445

Results and Discussion, 3.5. Correlation of Cu, Fe, Pb, and Zn in tree rings with atmospheric pollutants: Page 15, line 430: Kindly replace “are” by “were”.

Your comment has been addressed. L449

Results and Discussion, 3.5. Correlation of Cu, Fe, Pb, and Zn in tree rings with atmospheric pollutants: Page 15, line 432: Kindly adjust as follow: “showed”.

This concern has been carefully addressed. L451

Round 2

Reviewer 2 Report

Comments and Suggestions for Authors

All comments and suggestions have been carefully incorporated accordingly.

Author Response

We thank the reviewer for their positive assessment. All previous comments and suggestions have been carefully addressed in the revised manuscript.

Reviewer 3 Report

Comments and Suggestions for Authors

The manuscript has been substantially revised.

Author Response

We thank the reviewer for their positive feedback and for acknowledging the substantial revisions made to the manuscript.

Reviewer 4 Report

Comments and Suggestions for Authors

Comments to the Author:

Title: Tree Rings of Pinus greggii Engelm. as Biomonitoring Proxies of Urban Heavy Metal Pollution in the Mexico City Metropolitan Area

Overview and general recommendation:

Authors have made significant improvements to their manuscript and are well thanked for that. Only minor linguistic adjustments are still required.

My comments and queries for authors are detailed below in “Minor comments” section.

Minor comments:

Introduction: Page 3, line 118: Kindly adjust as follow: “hypotheses”.
Materials and Methods, 2.1. Study area: Page 3, line 123: Kindly adjust the numbering of this paragraph as “2.1.” instead of “2.”
Materials and Methods, 2.2. Annual tree-ring growth analysis: Page 5, lines 154-155: “Given… species”: Kindly avoid the first voice form of the sentence and adopt the impersonal form instead.
Materials and Methods, 2.3. Cross-dating and dendrochronological analysis: Page 5, line 167: Kindly adjust the numbering of this paragraph as “2.3.” instead of “2.4.”
Materials and Methods, 2.4. Climatic variables and tree growth response: Page 5, line 184: Kindly adjust the numbering of this paragraph as “2.4.” instead of “2.5.”
Materials and Methods, 2.5. Dendrochemical analysis of tree rings: Page 6, line 197: Kindly adjust the numbering of this paragraph as “2.5.” instead of “2.6.”
Materials and Methods, 2.6. Statistical analysis of chemical elements in tree rings: Page 7, line 235: Kindly adjust the numbering of this paragraph as “2.6.” instead of “2.7.”
Results and Discussion, 3.2. Effect of climatic variables on Pinus greggii growth: Page 9, line 293: Kindly adjust as follow: “enhanced”.
Results and Discussion, 3.4. Temporal trends in the concentrations of heavy metals Fe, Cu, Zn, and Pb in tree rings and their relationship with atmospheric pollutants: Page 11, line 353: Kindly adjust as follow: “did not find”.
Results and Discussion, 3.4. Temporal trends in the concentrations of heavy metals Fe, Cu, Zn, and Pb in tree rings and their relationship with atmospheric pollutants: Page 11, lines 353-356: “We did not… (Figure 5)”: Kindly avoid the first voice form of these sentences and adopt the impersonal form instead.
Results and Discussion, 3.4. Temporal trends in the concentrations of heavy metals Fe, Cu, Zn, and Pb in tree rings and their relationship with atmospheric pollutants: Page 12, line 376: Kindly adjust as follow: “modulated”.
Results and Discussion, 3.5. Correlation of Cu, Fe, Pb, and Zn in tree rings with atmospheric pollutants: Page 14, line 404: Kindly adjust as follow: “showed”.

Comments on the Quality of English Language

Minor linguistic adjustments are still required. Most needed adjustments are mentioned in the "Minor comments" section within the attached report.

Author Response

We sincerely thank the reviewer for their careful reading and valuable suggestions. All minor linguistic and formatting corrections have been addressed as detailed below. For clarity, all modifications have been highlighted in red in the revised manuscript.

Minor comments:

Comment 1: Introduction: Page 3, line 118: Kindly adjust as follows: “hypotheses”.

Response:

The suggested correction has been implemented by replacing “hypothesis” with “hypotheses” (Page 3, Line 118).

Comment 2: Materials and Methods, 2.1. Study area: Page 3, line 123: Kindly adjust the numbering of this paragraph as “2.1.” instead of “2.”

Response:

The paragraph numbering has been corrected accordingly (Page 3, Line 123).

Comment 3: Materials and Methods, 2.2. Annual tree-ring growth analysis: Page 5, lines 154–155: Kindly avoid the first-person voice and adopt an impersonal form.

Response:

The sentence has been revised to adopt an impersonal construction, avoiding first-person voice (Page 5, Lines 154–155).

Comment 4: Materials and Methods, 2.3.: Page 5, line 167: Kindly adjust the numbering to “2.3.” instead of “2.4.”

Response:

The section numbering has been corrected (Page 5, Line 167).

Comment 5: Materials and Methods, 2.4.: Page 5, line 184: Kindly adjust the numbering to “2.4.” instead of “2.5.”

Response:

The section numbering has been corrected (Page 5, Line 184).

Comment 6: Materials and Methods, 2.5.: Page 6, line 197: Kindly adjust the numbering to “2.5.” instead of “2.6.”

Response:

The section numbering has been corrected (Page 6, Line 197).

Comment 7: Materials and Methods, 2.6.: Page 7, line 235: Kindly adjust the numbering to “2.6.” instead of “2.7.”

Response:

The section numbering has been corrected (Page 7, Line 235).

Comment 8: Results and Discussion, Page 9, line 293: Kindly adjust as follows: “enhanced”.

Response:

The suggested correction has been implemented (Page 9, Line 293).

Comment 9: Results and Discussion, Page 11, line 353: Kindly adjust as follows: “did not find”.

Response:

The wording has been corrected accordingly (Page 11, Line 353).

Comment 10: Page 11, lines 353–356: Kindly avoid first-person voice and adopt an impersonal form.

Response:

The text has been revised to reduce the use of first-person expressions and to adopt a predominantly impersonal construction (Page 11, Lines 353–356).

Comment 11: Page 12, line 376: Kindly adjust as follows: “modulated”.

Response:

The suggested correction has been implemented (Page 12, Line 376).

Comment 12: Page 14, line 404: Kindly adjust as follows: “showed”.

Response:

The suggested correction has been implemented (Page 14, Line 404).