Spatial Patterns of Stem Tissue Carbon Content in Fagaceae Species from Typical Forests in China
, Wenjing Li 1,2, Xiaoyi Chao 2,4 and Xingchang Wang 2,4,*
Round 1
Reviewer 1 Report
Comments and Suggestions for AuthorsDear Authors
My comments on your article are stated below.
Abstract Part:
-In the abstract, the most prominent of the 13 sites in terms of the features examined should be highlighted and numerical values should be given.
-Furthermore, the carbon content among the three tissues should be highlighted with numerical values.
Introduction Part:
- The importance of selecting Fagaceae species in terms of region and carbon content should be emphasized. In particular, the chemical properties of the studied Fagaceae species and their advantages over other species should be explained in more detail and with greater emphasis.
-The hypothesis and aims of the study should be rewritten by implying the study
Materials and Methods Part:
- The year of the research should be stated.
- The meaning of abbreviations should be written under the table.
- It should be stated whether the climate data given is climate data covering many years or is it the average data of the year examined. Mean humidity should also be given in this table.
- The table should include the elevation of the locations where samples were collected.
- Although the authors stated, "The wide sampling area and rich species diversity in these sampling areas provide a basis for examining patterns of geographic variation," this is insufficient as a sample selection criterion. An examination of Table 1 reveals significant differences among the selected areas. Please describe your criteria for selecting these areas in more detail and clearly.
- The time when stem tissue sampling was performed should be specified. Indicate whether samples were taken at the same time at all 13 sites or at different times. If taken at different times, the reasons should be stated.
- Explain clearly the method of separating core samples into sapwood and heartwood based on color and moisture status.
- Reference should be given to the method used to determine the carbon content.
Result part:
The results are presented very generally. The differences between the 13 sites can be compared with differences in climate, altitude, and coordinates to interpret potential differences. In other words, a link can be established between the values in Table 1 and the results. Furthermore, the possible reasons for the differences among Fagaceae species can be interpreted. The results need to be improved. As is, they are inadequate.
Discussion Part:
- The discussion should be divided into subtitles according to the Results part. Also, new references should be added to this part to improve the discussion part.
Conclusion Part:
-This part should be rewritten by giving important results of the study for examined properties. Also, new findings should be given for the clarity of the study.
Best regards,
Author Response
Dear Authors
My comments on your article are stated below.
Abstract Part:
-In the abstract, the most prominent of the 13 sites in terms of the features examined should be highlighted and numerical values should be given.
Reply: Thank you very much for this suggestion. We added key results with numerical values.
-Furthermore, the carbon content among the three tissues should be highlighted with numerical values.
Reply: Added.
Introduction Part:
- The importance of selecting Fagaceae species in terms of region and carbon content should be emphasized. In particular, the chemical properties of the studied Fagaceae species and their advantages over other species should be explained in more detail and with greater emphasis.
Reply: Thank you very much for this invaluable suggestion. We added the importance of selecting Fagaceae species with key references.
-The hypothesis and aims of the study should be rewritten by implying the study.
Reply: We revised the hypotheses and aims.
Materials and Methods Part:
- The year of the research should be stated.
Reply: Added.
- The meaning of abbreviations should be written under the table.
Reply: Added.
- It should be stated whether the climate data given is climate data covering many years or is it the average data of the year examined. Mean humidity should also be given in this table.
Reply: These data were means for many years’ observations. The humidity is not available for many sites, so we did not list it.
- The table should include the elevation of the locations where samples were collected.
Reply: Added.
- Although the authors stated, "The wide sampling area and rich species diversity in these sampling areas provide a basis for examining patterns of geographic variation," this is insufficient as a sample selection criterion. An examination of Table 1 reveals significant differences among the selected areas. Please describe your criteria for selecting these areas in more detail and clearly.
Reply: Thank you very much for this invaluable suggestion. We added the forest biomes and geographical range.
- The time when stem tissue sampling was performed should be specified. Indicate whether samples were taken at the same time at all 13 sites or at different times. If taken at different times, the reasons should be stated.
Reply: We added the season of the sampling in Section 2.2: “The field sampling was conducted in the summers from 2020 to 2025.”
- Explain clearly the method of separating core samples into sapwood and heartwood based on color and moisture status.
Reply: Thank you very much for this suggestion. We added detailed method for separating sapwood and heartwood. “The sapwood had higher water content and was light-colored versus heartwood, thus sapwood was usually semi-transparent under sun light (or artificial beam light). The sapwood-heartwood transition zone, if occurred, was sorted into heartwood.”
- Reference should be given to the method used to determine the carbon content.
Reply: Added.
Result part:
The results are presented very generally. The differences between the 13 sites can be compared with differences in climate, altitude, and coordinates to interpret potential differences. In other words, a link can be established between the values in Table 1 and the results. Furthermore, the possible reasons for the differences among Fagaceae species can be interpreted. The results need to be improved. As is, they are inadequate.
Reply: Thank you very much for these suggestions! We did not compare among the 13 sites or site-groups because the number of species and individuals was quite imbalanced among these sites. We only sampled 41 species, but there are 279 native Fagaceae species in China. Comparison between species was not an effective method, because northern sites only have one species and only one or two individual trees for 17 species. The difference among Fagaceae species was not the most important source of total variation, often lower than the residual (Figure 1). We interpreted part of inter-site variation relating to climatic and geographical factors (Figure 4). So interpreting the inter-specific differences was not the main objective of this study. We added Table 2 to show the species-mean carbon contents by tissue.
Discussion Part:
- The discussion should be divided into subtitles according to the Results part. Also, new references should be added to this part to improve the discussion part.
Reply: Thank you very much for this suggestion. We did not use subtitles in the Discussion, because there were very few references directly related to our topics. However, each paragraph was a topic, responding to the Results part. And most related references were cited in the Introduction or Method sections, so there were very few new references. We added three new references in Discussion.
Conclusion Part:
-This part should be rewritten by giving important results of the study for examined properties. Also, new findings should be given for the clarity of the study.
Reply: Thank you very much for this suggestion. We revised this part.
Best regards,
Thank you very much for your invaluable comments and suggestions again!
Author Response File: 
Author Response.pdf
Reviewer 2 Report
Comments and Suggestions for AuthorsBrief summary:
The manuscript presents a study about the stem carbon content of Fagaceae species within representative forest ecosystems in China. Variations in carbon concentration across different tissues were assessed, together with the spatial distribution patterns and the influence of geographical drivers.
In general terms, the research could contribute to a more comprehensive understanding of carbon storage strategies in woody plants and offer parameters for improving the accuracy of forest carbon accounting. Overall, no significant improvements were detected.
Specific comments:
- In line 93, it would be advisable to include a new column in the table that identifies the name of the species listed, identifying how many trees have been studied for each of them. In Figure 2, the number of castanea trees (15), fagus (4)… can be counted, but it would be scientifically positive to identify them by “site” and by “no. of trees”. In addition, “site” Fengyangshan identifies up to 10 species. What are they?
- Line 120-121: the link doesn´t work.
- Lines 200-201 and lines 234-235: bark is indicated as inferior in all cases, followed by sapwood and finally heartwood. However, lines 145 to 150 and Fig. 2 do not show this. Lithocarpus shows a different result.
- Siguiendo lo indicado anteriormente, no queda claro al revisor una diferencia significativa entre sapwood y heartwood. Sería conveniente matizar este aspecto. Los valores medios y desviaciones son muy próximas. Obtener inferencia estadística entre las especies y los tres tipos de material analizado (similar ala de la figura 3) mostraría una diferencia significativa o no.
- Following the above, the reviewer is unclear about a significant difference between sapwood and heartwood. It would be helpful to clarify this aspect. The mean values and deviations are very close. Obtaining statistical inferences between the species and the three types of material analyzed (similar to that in Figure 3) would reveal a significant difference or not.
Comments for author File: Comments.pdf
Author Response
Brief summary:
The manuscript presents a study about the stem carbon content of Fagaceae species within representative forest ecosystems in China. Variations in carbon concentration across different tissues were assessed, together with the spatial distribution patterns and the influence of geographical drivers.
In general terms, the research could contribute to a more comprehensive understanding of carbon storage strategies in woody plants and offer parameters for improving the accuracy of forest carbon accounting. Overall, no significant improvements were detected.
Reply: Thank you very much for these comments. We tried our best to improve the clarity of the methods, significance of results and conclusion.
Specific comments:
- In line 93, it would be advisable to include a new column in the table that identifies the name of the species listed, identifying how many trees have been studied for each of them. In Figure 2, the number of castanea trees (15), fagus (4)… can be counted, but it would be scientifically positive to identify them by “site” and by “no. of trees”. In addition, “site” Fengyangshan identifies up to 10 species. What are they?
Reply: Thank you very much for these suggestions. We combined the numbers of species and trees to one column, then added a new column to show how many trees were studied for each species. For many species, it was difficult to find three healthy mature individuals. This information significantly improved the transparency of the sampling design.
- Line 120-121: the link doesn´t work.
Reply: I am sorry for this issue. I tried this link (https://developers.google.com/earth-engine/datasets/catalog/ECMWF_ERA5_LAND_HOURLY#bands) and confirmed that it did work. Maybe you can try again or check your internet.
- Lines 200-201 and lines 234-235: bark is indicated as inferior in all cases, followed by sapwood and finally heartwood. However, lines 145 to 150 and Fig. 2 do not show this. Lithocarpus shows a different result.
Reply: Sorry for this confusion. We noted this slight difference, thus added a new sentence at the end of this paragraph: “However, there were no significant differences between stem tissues for Castanea, Fagus, and Lithocarpus species.”
- Following the above, the reviewer is unclear about a significant difference between sapwood and heartwood. It would be helpful to clarify this aspect. The mean values and deviations are very close. Obtaining statistical inferences between the species and the three types of material analyzed (similar to that in Figure 3) would reveal a significant difference or not.
Reply: Sorry for this confusion. Although the mean and standard deviation of the three stem tissues seemed close to each other, the difference between tissues was significant (p < 0.001) because of the large sample size (n > 100). Comparison between species was not performed because some species only had one tree sampled. We prefer using the variance decomposition to partition the total variation (Refer to Figure 1 for details).
Author Response File: Author Response.pdf
Reviewer 3 Report
Comments and Suggestions for AuthorsTopic of the MS was good, and presentation is well but need few corrections before acceptance.
- Abstract: need modification, it should be data based
- Introduction: Hypothesis and objective of the study missing.
- Methodology: sampling need improvement and elaboration is also need for quantification of carbon content.
- Results: Well presented
- Discussion: Well presented
- Conclusion: Need improvement. it should be compact and data based.
- References: Kindly check. (Kindly see the attached PDF)
Comments for author File: Comments.pdf
Author Response
Topic of the MS was good, and presentation is well but need few corrections before acceptance.
- Abstract: need modification, it should be data based.
Reply: Thank you very much for this suggestion. We added important data to support the key results.
- Introduction: Hypothesis and objective of the study missing.
Reply: We added hypothesis and objective.
- Methodology: sampling need improvement and elaboration is also need for quantification of carbon content.
Reply: We added the details of sampling and carbon determination.
- Results: Well presented.
Reply: Thanks.
Discussion: Well presented
Reply: Thanks.
- Conclusion: Need improvement. It should be compacted and data based.
Reply: Thank you for this suggestion. We revised this section.
- References: Kindly check. (Kindly see the attached PDF)
Reply: Thanks and checked.
Author Response File: Author Response.pdf
Round 2
Reviewer 1 Report
Comments and Suggestions for AuthorsDear Authors,
I've reviewed it and would like to report that it's acceptable.
Best regards,
Author Response
Thanks for your advice.
