Altitudinal Difference of Growth–Climate Response Models in the Coniferous Forests of Southeastern Tibetan Plateau, China

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

The manuscript investigated the impacts of climate and elevation on Picea likiangensis in the southeastern Tibetan Plateau, China. The study fills important knowledge gaps of the effects of elevation. They found minimum temperature drives radial growth at lower and medium latitude while SPEI from the previous year influence those at higher altitude. They also found the patterns are similar in Sabina and Abies. They found the differences can be attributed to both biotic and abiotic factors. - Abstract: a couple of acronyms were not defined: DPM, DPH, DPL. - Introduction: L49-50; L 57-58; you can find more support from literature such as Qiu et al., 2021, FEE and Clark et al., 2007, Ecol. Appl. These are paper in the forests of North America, which include similar genera of Picea and Abies. - Figure 3: there is a strong warming trend in the data, did the author compare this trend across elevation gradient? Or consider de-trending the data? - Figure 5: what is the gray colored background? Please also explain TRI, EPS, Rbar, Num in the axis label. The font in the figure should also be increased so that readers can clearly examine the pattern. - Discussion: L329-342; the effects of tree age is a good discussion point. Some of the recent studies found that large trees have different physiological characteristics compared to intermediate trees (Qiu et al., 2021, PNAS and Cannon et al., 2022, Nat. Plants). Even though tree age data is not directly measured, tree size can still indirectly influence it. - Discussion: maybe I have missed it, but I could not find the explanation why temperature from specific months (previous November to Current august) affects the radial growth patterns. Clark, J. S., Wolosin, M., Dietze, M., IbáÑez, I., LaDeau, S., Welsh, M., & Kloeppel, B. (2007). Tree growth inference and prediction from diameter censuses and ring widths. Ecological Applications, 17(7), 1942-1953. Qiu, T., Sharma, S., Woodall, C. W., & Clark, J. S. (2021). Niche shifts from trees to fecundity to recruitment that determine species response to climate change. Frontiers in Ecology and Evolution, 9, 719141. Qiu, T., Aravena, M. C., Andrus, R., Ascoli, D., Bergeron, Y., Berretti, R., ... & Clark, J. S. (2021). Is there tree senescence? The fecundity evidence. Proceedings of the National Academy of Sciences, 118(34), e2106130118. Cannon, C. H., Piovesan, G., & Munné-Bosch, S. (2022). Old and ancient trees are life history lottery winners and vital evolutionary resources for long-term adaptive capacity. Nature Plants, 8(2), 136-145.

 

Comments on the Quality of English Language

Minor editing of English language required

Author Response

Dear reviewer,

We greatly appreciate the reviewers' constructive and insightful comments for our manuscript entitled “Growth response of Picea likiangensis to climate along an elevation gradient of the Haizi mountain in the southeastern Tibetan Plateau, China” (ID: forests-3076373).

Your comments are very valuable and helpful for improving our manuscript. In this revision, we have carefully considered all the feedback and made conscientious corrections.

The major revisions in the new manuscript are:

1. reconsidered and devised a new title. the new title is “ Altitudinal difference of growth-climate response models in the coniferous forests of southeastern Tibetan Plateau, China”;
2. reduced the abstract to 200 words as requested;
3. added our research hypotheses in the introduction;
4. incorporated the methods we used into the manuscript, including the sample processing procedures, the methodology for establishing chronologies, detrending methods, and details on the sources of meteorological data;
5. added more contents about forest type in introduction and materials, and further discussed the influence of forest type and tree age in discussion;
6. adjusted all figures and captions to enhance readability;
7. streamlined the conclusion;
8. updated the reference formatting.

The minor revisions include: added necessary references, incorporated statistical data and specified the locations of other studies, corrected grammatical issues and unclear sentences throughout the manuscript, standardized the representation of months, etc.

Our point-to-point responses are detailed in the attached document.

Author Response File: Author Response.docx

Reviewer 2 Report

Comments and Suggestions for Authors

Dear Editor,

The authors of the manuscript aimed to understand how tree growth responds to climate change along altitudinal gradients in the southeastern Tibetan Plateau, comparing these responses among different tree species (Picea likiangensis, Sabina saltuaria, Abies squamata) and within the same species (Picea likiangensis) at different altitudes. Although the research topic is of considerable interest to the readers of "Forests," the manuscript requires major revision before it can be considered for publication. Specifically, the methods and the presentation of results need significant improvement.

The authors did not provide a file with line numbers; therefore, I am attaching the PDF of the manuscript containing my comments. For the future, I suggest that the authors include line numbers in the text.

Best regards.

Comments for author File: Comments.pdf

Author Response

Dear reviewer,

We greatly appreciate the reviewers' constructive and insightful comments for our manuscript entitled “Growth response of Picea likiangensis to climate along an elevation gradient of the Haizi mountain in the southeastern Tibetan Plateau, China” (ID: forests-3076373).

Your comments are very valuable and helpful for improving our manuscript. In this revision, we have carefully considered all the feedback and made conscientious corrections.

The major revisions in the new manuscript are:

1. reconsidered and devised a new title. the new title is “ Altitudinal difference of growth-climate response models in the coniferous forests of southeastern Tibetan Plateau, China”;
2. reduced the abstract to 200 words as requested;
3. added our research hypotheses in the introduction;
4. incorporated the methods we used into the manuscript, including the sample processing procedures, the methodology for establishing chronologies, detrending methods, and details on the sources of meteorological data;
5. added more contents about forest type in introduction and materials, and further discussed the influence of forest type and tree age in discussion;
6. adjusted all figures and captions to enhance readability;
7. streamlined the conclusion;
8. updated the reference formatting.

The minor revisions include: added necessary references, incorporated statistical data and specified the locations of other studies, corrected grammatical issues and unclear sentences throughout the manuscript, standardized the representation of months, etc.

Our point-to-point responses are detailed in the attached document.

Author Response File: Author Response.docx

Reviewer 3 Report

Comments and Suggestions for Authors

Another dendroclimate study in high elevation China.  Always of interest generally, and this one with an altitudinal gradient component, even better.  Some comments:

Has Forests changed its format for listing cited sources in the text?  Author’s names now, instead of numbers?  But, the list of references still has numbers, though is alphabetized anyway?

Page 2: elevational gradient: I see that this is an emphasis of the study, but my first impression was that all the sites were high (very high) in elevation.  In the US, I can’t recall seeing any forests at such high elevations.  If trees are this high here, they’re Krumholz at best.

Figures: In general, as printed out on paper, many of the figures have text (like axis labels) that is too small to discern easily, at least by eyesight diminished by age, like mine.

Page 5: detrending method: yes, but what exactly was the detrending method?  I seem to have missed that detail.  If it was in Supplemental Info, shouldn’t that be included in the main paper?

Figure 4: Do the different colors mean anything?

Table 2: I see that SNR varies similarly with sample size, which is a known relationship, actually.  SNR is difficult to interpret because of that.  Meanwhile, BTR?  Is that the true Rbar, the average correlation between each tree and the chronology?  To be honest, the values listed for BTR are not strong, or at least higher Rbar values have been reported in other dendroclimate studies.

Page 7: SPEI?  Has that abbreviation been identified yet in the ms?  It’s a precipitation index, correct?

Page 7: perception (mean maximum temperature): perception means what is in the parens?  I’ve not ever seen perception used that way.

Page 7: indicted.  Pretty sure that’s not the correct word here.

Page 8: seasonal correlations: It says these seasonal correlations are given in S2.  I would put them in with the monthly correlations, i.e., Figure 6, for readers not likely to access S2.

Figure 6: Why lines in one case (temperature) but bars in the other (precipitation)?  Bars are more conventional for this kind of data graphic.

Figure 6: No 0.0 horizontal reference line for the temperature values?  Another reason to go with bars.

Page 9: influence of altitude on tree growth was not uniform in the STP.  Not surprising, frankly, as, again, all three of the spruce sites are very high in elevation compared to anything in US dendroclimatology.

Page 9: complanate?  Not sure what this word means here.

Reference list: 80 sources listed, good and strong.

Comments on the Quality of English Language

Pretty good English language, but several style/grammar errors or uncertainties to be checked.

Author Response

Dear reviewer,

We greatly appreciate the reviewers' constructive and insightful comments for our manuscript entitled “Growth response of Picea likiangensis to climate along an elevation gradient of the Haizi mountain in the southeastern Tibetan Plateau, China” (ID: forests-3076373).

Your comments are very valuable and helpful for improving our manuscript. In this revision, we have carefully considered all the feedback and made conscientious corrections.

The major revisions in the new manuscript are:

1. reconsidered and devised a new title. the new title is “ Altitudinal difference of growth-climate response models in the coniferous forests of southeastern Tibetan Plateau, China”;
2. reduced the abstract to 200 words as requested;
3. added our research hypotheses in the introduction;
4. incorporated the methods we used into the manuscript, including the sample processing procedures, the methodology for establishing chronologies, detrending methods, and details on the sources of meteorological data;
5. added more contents about forest type in introduction and materials, and further discussed the influence of forest type and tree age in discussion;
6. adjusted all figures and captions to enhance readability;
7. streamlined the conclusion;
8. updated the reference formatting.

The minor revisions include: added necessary references, incorporated statistical data and specified the locations of other studies, corrected grammatical issues and unclear sentences throughout the manuscript, standardized the representation of months, etc.

Our point-to-point responses are detailed in the attached document.

Author Response File: Author Response.docx

Reviewer 4 Report

Comments and Suggestions for Authors

Dear colleagues, your manuscript is very interesting. Your research solved the classical problem of radial growth – climate (weather) relationships. But it was conducted in the unique region and the obtained results are also unique.

The quality of the research and conclusions is undoubted, but your text must be improved in some aspects, which are listed below.

Major comments:

The P.likiangensis description (first paragraph of section 2.2.) should contain the references.

In the section 2.2. (Sample collection and dendrochronological analyses [analysis!]) there in no information about analysis. How did you prepare the cores and measure the ring width? What software did you use for dendrochronological statistic calculation? Did you conduct the cross-dating and detrending procedures? How do you estimate the relationships between weather and tree-ring width and what periods did you examined (from and to what years? what seasons)? This information is obligate. As examples of appropriate presentation I can recommend, e.g., DOI 10.1016/j.foreco.2011.10.017 and 10.1007/s40333-018-0025-y.

Special comment should be make for month under analysis. How can you explain the statistically significant correlation between TRW and weather in current November and December (11 and 12 ticks on Figure 6)? Is the cambium of Picea likiangensis and/or wood cells lignification active in this season?

The forest type is listed as factor influencing the growth reaction to weather. But the text contains no data about this site characteristic. Please, describe the forest types of your sites and their influence on radial growth or remove the forest type from the list of factors.

Minor comments:

Please, italicize ‘Abies spectabilis’ in this sentence: ‘For instance, in the Manang valley of the central Himalayas, it was observed that spring and summer rainfall, rather than summer temperature, determined the growth of Abies spectabilis at high-elevation sites (Rai et al., 2020)’. The same mistake was made in the many sentences below.

The ‘var.’ must not be italicized, e.g.: ‘Picea likiangensis var. balfouriana (P.likiangensis) is a high-altitude conifer widely distributed in Sichuan province and it is the main tree species composite subalpine forests’. 

‘Gou et al. (2013) found that the tree growth of Abiesforrestii Coltm. which grew...’ Please, add the space after Abies and format authority as non-italicized.

The font size on the legend to Figure 1a and on the Figure 1b (sampling sites captions) is too small and not readable. Same with the Figures 4 to 7.

What do the dashed lines mean on Figure 6? Also, please, explain the ‘P’ letter in the axis tick marks.

 

Author Response

Dear reviewer,

We greatly appreciate the reviewers' constructive and insightful comments for our manuscript entitled “Growth response of Picea likiangensis to climate along an elevation gradient of the Haizi mountain in the southeastern Tibetan Plateau, China” (ID: forests-3076373).

Your comments are very valuable and helpful for improving our manuscript. In this revision, we have carefully considered all the feedback and made conscientious corrections.

The major revisions in the new manuscript are:

1. reconsidered and devised a new title. the new title is “ Altitudinal difference of growth-climate response models in the coniferous forests of southeastern Tibetan Plateau, China”;
2. reduced the abstract to 200 words as requested;
3. added our research hypotheses in the introduction;
4. incorporated the methods we used into the manuscript, including the sample processing procedures, the methodology for establishing chronologies, detrending methods, and details on the sources of meteorological data;
5. added more contents about forest type in introduction and materials, and further discussed the influence of forest type and tree age in discussion;
6. adjusted all figures and captions to enhance readability;
7. streamlined the conclusion;
8. updated the reference formatting.

The minor revisions include: added necessary references, incorporated statistical data and specified the locations of other studies, corrected grammatical issues and unclear sentences throughout the manuscript, standardized the representation of months, etc.

Our point-to-point responses are detailed in the attached document.

Author Response File: Author Response.docx

Round 2

Reviewer 2 Report

Comments and Suggestions for Authors

Dear Editor,

In this revised version of the manuscript, the authors have addressed my previous doubts and concerns comprehensively. They have also improved the materials and methods section, enhancing the clarity and rigor of the study's framework. Additionally, the presentation and discussion of the results have been significantly improved, offering deeper insights and more robust conclusions.

Given these substantial improvements, I suggest that the manuscript be accepted in its current form.

Best regards.

Reviewer 4 Report

Comments and Suggestions for Authors

Dear Authors, 

I have no more comments to Your manuscript without one exclusion: in the Fig. 1 caption Your must use 'triangle' instead of 'pentacle'. 

I happy I could help you. 

Best wishes!