Environmental Factors Affecting Volume Growth of Yellow Poplar Plantations in South Korea

Round 1

Reviewer 1 Report

Dear authors,

Please see the feedback in the letter's comments letter.

 

Comments for author File: Comments.docx

Please see the feedback in the letter's comments letter.

Author Response

We appreciate your valuable comments and suggestions. We couldn't have improved our manuscript without your help.

 

• The title of your abstract is too long and does not clearly convey the main objective and findings of your study. I suggest you shorten it and make it more specific. For example, you could use something like "Environmental factors affecting growth and adaptation of yellow poplar plantations in South Korea".

 

We accept your suggestion. We changed the title.

 

• The introduction of your abstract is too vague and does not provide enough background information or context for your study. You should explain why yellow poplar is an important species, what are the benefits and challenges of planting it in non-native ranges, and what are the knowledge gaps that your study aims to fill. You should also state your research question or hypothesis clearly.

 

We completely revised abstract.

 

• The methods section of your abstract is too detailed and technical, and does not highlight the novelty or significance of your approach. You should focus on describing the main aspects of your experimental design, such as the number and location of the stands, the selection criteria of the trees, the environmental variables measured, and the statistical methods used. You should also mention any limitations or assumptions of your methods.

 

We considered your opinion and revised the section. .

 

• The results section of your abstract is too descriptive and does not emphasize the main findings or implications of your study. You should summarize the main results in terms of the relationships between volume growth and environmental factors, and explain how they differ among wood and fungal species. You should also mention any unexpected or surprising results, and how they contribute to the existing knowledge or challenge the previous assumptions.

 

Our research highlights were summarized.

 

• The abstract lacks a clear statement of the study's overall significance. It would be beneficial to highlight the broader implications of the findings and their potential contribution to the field of forestry or ecological restoration.

 

we revised it

 

# Introduction:

The introduction of the paper is well-written and provides a clear background and context for the study. The authors explain why yellow poplar is an important species, what are the benefits and challenges of planting it in non-native ranges, and what are the knowledge gaps that the study aims to fill. Theathours  also state your research question and hypothesis clearly.

However, the introduction of the  paper is also too long and contains some redundant or unnecessary information. You should try to shorten it and make it more concise and focused. For example, you could omit some details about the climatic conditions in Korea and the native range of yellow poplar, as they are not directly relevant to your research question. You could also merge some paragraphs that discuss similar topics, such as the factors influencing tree growth or the objectives and methods of your study.

We omitted some paragraphs and almost rewrote the Introduction to accommodate your opinion.

 

• The introduction of the paper also lacks some citations to support your claims and statements. You should provide references to the sources that you used to obtain the information about yellow poplar, its native range, its adaptation, its plantation in Korea, and its susceptibility to climate change. You should also cite some previous studies that have investigated the relationship between environmental factors and tree growth, especially for yellow poplar or other non-native species.

 

We included the seed source.

We expanded our reference list..

• The introduction of the paper also needs some improvement in terms of the structure and flow of your arguments. You should use transitions and connectors to link your paragraphs and sentences, and to guide the reader from the general background to the specific research question.

 

It was revised.

 

#  Materials and Methods:

The materials and methods section of the paper is well-organized and provides a clear description of the study areas, the climate data, the volume growth measurement, and the climatic distance calculation. The authors explain the reasons for choosing the 49 yellow poplar stands, the 129 plots, and the five dominant trees for analysis. The authors also describe the methods and equipment used for adjusting and measuring the environmental variables, the soil properties, and the volume growth of the trees. You also state the formulas and the statistical methods used for calculating the climatic distance and the correlation coefficients.

• However, the materials and methods section of the paper is also too long and contains some redundant or unnecessary information. You should try to shorten it and make it more concise and focused. For example, you could omit some details about the climatic conditions in Korea and the native range of yellow poplar, as they are not directly relevant to your research question. You could also merge some paragraphs that discuss similar topics, such as the climate data extraction or the climatic distance calculation.

 

As you suggested, climate information in both Korea and the native range was shortened.

 

• The materials and methods section of the paper also lacks some citations to support your claims and statements. You should provide references to the sources that you used to obtain the information about yellow poplar, its native range, its adaptation, its plantation in Korea, and its susceptibility to climate change. You should also cite some previous studies that have used similar methods or techniques to investigate the relationship between environmental factors and tree growth, especially for yellow poplar or other non-native species.

 

We added the past research  in discussion section.

 

• The materials and methods section of the paper also needs some improvement in terms of the clarity and accuracy of your language and terminology. You should use consistent and precise terms to describe your variables, units, formulas, and methods. You should also avoid using abbreviations or acronyms that are not defined or explained in your paper. You should also check your grammar, spelling, punctuation, and formatting for any errors or inconsistencies.

 

• We used an English grammar program to improve our writing.

 

# Results and discussion

I recommend that authors consider temperature variables and other variables that could impact volume growth, and request further analysis or discussion on these potential influences.

 

We checked the results again. As described in abstract, results, and discussion, we identified wind exposure as the most critical factor, followed by other minor variables. And revised the manuscript.

 

The authors should explain why you used Kim et al. [15] as your main reference, and how their study is relevant or comparable to yours.

 

We did not intend  it as our main reference.

The correlation between soil P2O5 content and volume growth is described as moderately negative. Can you discuss any potential mechanisms or explanations for this negative correlation? It would be helpful to understand how soil P2O5 content affects yellow poplar growth and whether there are any specific thresholds or ranges that should be considered for optimal growth.

 

Discussed it in Discussion section.

The study suggests that further research is needed to understand the complex interplay between topographic variables and yellow poplar volume growth in Korea. It would be helpful if the authors could provide some specific research questions or hypotheses that could be addressed in future studies.

 

We did.

 

# Conclusion

The conclusion section of your paper is also too long. You should try to shorten it and make it more concise and focused on the obtained results.

 

We revised it completely and made it shorter.

 

Thank you

Reviewer 2 Report

From my subjective point of view as a reader, the topic is interesting, but the manuscript is still deficient and requires hard work, including restructuring.

It is preferable to mention the analysis method(s) in the Abstract. Possibly the most important, if there are several

Lines 10 and 11 are identical to lines 33 and 34.

The number of references in the Introduction is insufficient. The first one is to mention the study of poplar in 2003. The second quote refers to "subtle differences". And the other four are used to support the statements related to the physiographic conditions suitable for yellow poplar.

There is no hypothesis or research question in the introduction.
Although the citations are distributed in the Discussion section, they are also scarce.

Thus, a total of 16 papers are mentioned in the entire article, this suggests that the study is deficient.

In data analysis, the authors write "[...] the following programs were used: ANOVA, Tukey HSD test, Spearman correlation calculator, and box plot maker". If ANOVA is a program for the authors, how could they report the results?

There are expressions or words that seem to follow certain patterns throughout the text, so it is likely that the text or part of the text was written by Artificial Intelligence; for example, ChatGPT. If it is only a mistranslation of the original language, there would be no problem, but if an AI wrote the text, it might be worthwhile to reconsider things.

 

Author Response

We appreciate your time and efforts to review our manuscript. It was very helpful.

Here are our short reply. Please, check the manuscript.

 

From my subjective point of view as a reader, the topic is interesting, but the manuscript is still deficient and requires hard work, including restructuring.

We revised the manuscript according to the reviewer’s suggestions.

Abstract, Introduction, Discussion, and conclusion were almost rewritten to make it short and concise..

 

It is preferable to mention the analysis method(s) in the Abstract. Possibly the most important, if there are several

WE revised it to contain the methods

Lines 10 and 11 are identical to lines 33 and 34.

 

We rewrote both sections.

The number of references in the Introduction is insufficient. The first one is to mention the study of poplar in 2003. The second quote refers to "subtle differences". And the other four are used to support the statements related to the physiographic conditions suitable for yellow poplar.

We put some more reference in discussion session, We described 2003 paper in the section.

There is no hypothesis or research question in the introduction.
Although the citations are distributed in the Discussion section, they are also scarce.

 

We inserted hypothesis in the end of Introduction section.

Thus, a total of 16 papers are mentioned in the entire article, this suggests that the study is deficient.

 

We added 11 more

In data analysis, the authors write "[...] the following programs were used: ANOVA, Tukey HSD test, Spearman correlation calculator, and box plot maker". If ANOVA is a program for the authors, how could they report the results?

Thank you. We removed the paragraph.

 

There are expressions or words that seem to follow certain patterns throughout the text, so it is likely that the text or part of the text was written by Artificial Intelligence; for example, ChatGPT. If it is only a mistranslation of the original language, there would be no problem, but if an AI wrote the text, it might be worthwhile to reconsider things.

 

No, We are using a grammar checking program.

 

Reviewer 3 Report

lines 20-22: «Volume growth was negatively correlated with latitude, wind exposure, and soil P2O5 concentration, while positively correlated with annual mean temperature, low extreme temperature, and growing season temperature.» Obviously, all the climatic factors listed as positively correlated with tree growth are negatively correlated with latitude themselves. At this, the said negative correlation between volume growth and latitude is negligibly weak (see line 177, Table 1). Why are you even highlighting it in Abstract? Here, only climatic variables mentioned would be enough. Furthermore, did you mean to say «longitude» (instead «latitude») in this phrase? Correlation between longitude and growth is more significant (as indicated in Table 1).

lines 91-92: how deep soil samples were collected?

section 2.3: necessary is to explain calibration of tree volume growth in more details. Does the harvest table used reflect growth variability in climatically different districts of country? To calibrate the field data, did you use some growth equation or simply postulate growth value at the age of 20 years would be the same as indicated in the harvest table?

line 128: since soil and topographic variables are mentioned in the end of section 2.4, its title «Climatic distance …» is not appropriate. It is rather to write «Environmental distances …».

lines 152-154: did you combine distances calculated for topographic and soil variables in some total distance like in formula (2)?

section 2, generally: analyzing methods also should be described for the results presented in lines 259-260 and section 3.7. For variable combinations, how was the correlation calculated?

section 3.7 and lines 144-150, generally: before combining some variables, their reciprocal independence must be checked. Where is result of such a check?

lines 182-183 vs. 177: the analyzed volume growth looks more correlated with longitude than with latitude!

line 419: how was influence of genetics tested in this study???

lines 421-424 vs. Table 8: in these lines, the completed list of the most crucial factors seems to be voluntary enough. In fact, P2O5 demonstrates stronger and more significant correlation than factors of low temperature extremes and spring humidity.

Some technical notes:

lines 25-26: here, the abbreviations LT, GT, GP, and SH should be explained (the same as WE in line 25).

line 193: here, the mentioned values r= –0,32 and p<0,001 contradict the ones indicated for altitude in Table 1!

line 219 vs. Table 3: why is winter precipitation not shown in the table?

lines 270-271: here, the mentioned values r= –0,16 and p=0,275 contradict the ones indicated for slope position in Table 6!

lines 278-280: again, the mentioned value r= –0,53 contradicts the one indicated for wind exposure in Table 6!

line 322: correlation coefficient cannot take on the value 3,0!

line 360: here, why are temperature values expressed in Fahrenheit degrees (although other values are given as Celsius degrees – see sections 1, 2.2, and 3.3)?

line 361: the same question on rainfall units. Above (lines 214-218, 235-237) precipitation is expressed in millimeters.

lines 35-36: «poplar's adaptation in different regions was studied by planting and monitoring trees alongside other conifers». The word «other» is not suitable in this phrase because Liriodendron tulipifera isn’t a conifer species.

lines 141-142: in this context, the word «value» would reflect the sense of the phrase more exactly than «variable».

lines 296, 403: the collocation «azimuthal aspects of the plots» (like in lines 90-91, 405) is more common and clear than «azimuth directions of the plots».

line 412: «wind-exposed» would be more clear.

Author Response

Thank you your detailed and valuable suggestions. We appreciate your time and efforts.

 

lines 20-2: «Volume growth was negatively correlated with latitude, wind exposure, and soil P2O5 concentration, while positively correlated with annual mean temperature, low extreme temperature, and growing season temperature.» Obviously, all the climatic factors listed as positively correlated with tree growth are negatively correlated with latitude themselves. At this, the said negative correlation between volume growth and latitude is negligibly weak (see line 177, Table 1). Why are you even highlighting it in Abstract? Here, only climatic variables mentioned would be enough. Furthermore, did you mean to say «longitude» (instead «latitude») in this phrase? Correlation between longitude and growth is more significant (as indicated in Table 1).

 

You are right. We revised abstract to accommodate your opinion.

 

lines 91-92: how deep soil samples were collected?

 

Soil samples were taken from a depth of 5-10 cm below the organic layer

(inserted the sentence)

 

section 2.3: necessary is to explain calibration of tree volume growth in more details. Does the harvest table used reflect growth variability in climatically different districts of country? To calibrate the field data, did you use some growth equation or simply postulate growth value at the age of 20 years would be the same as indicated in the harvest table?

 

We used the rate of change in volume growth between different ages from a harvest table published in Korea. It can be inaccurate in some stands. We also think that correlation coefficients may be low because harvest tables can be inaccurate in some stands.

 

 

line 128: since soil and topographic variables are mentioned in the end of section 2.4, its title «Climatic distance …» is not appropriate. It is rather to write «Environmental distances …».

 

We revised it to environmental distances

 

lines 152-154: did you combine distances calculated for topographic and soil variables in some total distance like in formula (2)?

 

Yes, we believe that the standardized data is acceptable

 

section 2, generally: analyzing methods also should be described for the results presented in lines 259-260 and section 3.7. For variable combinations, how was the correlation calculated?

 

The standardized values of all variables were pooled and divided to obtain mean value. Rank correlation of the pooled mean value and volume growth was calculated.

 

section 3.7 and lines 144-150, generally: before combining some variables, their reciprocal independence must be checked. Where is result of such a check?

 

We inserted the sentences under section 3.7. Just below Table 8.

Thank you for your pointing out the important thing we missed. We calculated them and changed our manuscript and Table.

 

lines 182-183 vs. 177: the analyzed volume growth looks more correlated with longitude than with latitude!

 

We corrected it. Thank you.

 

line 419: how was influence of genetics tested in this study???

 

Because the trees were grown from seeds, we only know that they are from a seed orchard in Tennessee. We have limited information about the specific seed source. So, genetics tests are not possible here.

 

lines 421-424 vs. Table 8: in these lines, the completed list of the most crucial factors seems to be voluntary enough. In fact, P2O5 demonstrates stronger and more significant correlation than factors of low temperature extremes and spring humidity.

 

We corrected the sentence.

 

Some technical notes:

lines 25-26: here, the abbreviations LT, GT, GP, and SH should be explained (the same as WE in line 25).

We did it as you suggested.

 

line 193: here, the mentioned values r= –0,32 and p<0,001 contradict the ones indicated for altitude in Table 1!

 

Typo. Corrected.

 

line 219 vs. Table 3: why is winter precipitation not shown in the table?

 

Inserted.

lines 270-271: here, the mentioned values r= –0,16 and p=0,275 contradict the ones indicated for slope position in Table 6!

 

Checked the data and corrected.

 

lines 278-280: again, the mentioned value r= –0,53 contradicts the one indicated for wind exposure in Table 6!

 

Checked the data and corrected.

 

line 322: correlation coefficient cannot take on the value 3,0! 

0.3

line 360: here, why are temperature values expressed in Fahrenheit degrees (although other values are given as Celsius degrees – see sections 1, 2.2, and 3.3)?

 

Removed them

(revised whole paragraph)

 

line 361: the same question on rainfall units. Above (lines 214-218, 235-237) precipitation is expressed in millimeters.

 

Discussion was rewritten.

 

Comments on the Quality of English Language

lines 35-36: «poplar's adaptation in different regions was studied by planting and monitoring trees alongside other conifers». The word «other» is not suitable in this phrase because Liriodendron tulipifera isn’t a conifer species.

 

Removed the sentence

 

lines 141-142: in this context, the word «value» would reflect the sense of the phrase more exactly than «variable».

 

Thank you. We changed it as you suggested.

 

lines 296, 403: the collocation «azimuthal aspects of the plots» (like in lines 90-91, 405) is more common and clear than «azimuth directions of the plots».

 

Thank you. We changed it as you suggested.

 

line 412: «wind-exposed» would be more clear.

Thank you. We changed it as you suggested.

 

Round 2

Reviewer 1 Report

No comments. 

 Moderate editing of English language required

Author Response

I would like to express my sincere gratitude for taking the time to review our paper. Your insightful feedback has been invaluable in improving the quality of our work.

I clarify the analysis method in M&M. Also, we cited a reference which used Bayesian Generalized Linear Model (BGLM) with abiotic variables, and wrote sentences the future work with our results at the end of the discussion. Also, add a reference [28].

Author Response File: Author Response.docx

Reviewer 2 Report

The article has improved significantly.
I have only a few small suggestions.

1) For the selection of the four variables mentioned in L. 126–127, was Spearman's rank coefficient used? Clarify, please.

2) In lines 142-143, when the authors write "were highly correlated with yellow poplar growth (r > 0.3, p < 0.05)", did they use Spearman's or Pearson's coefficient?

3) The axes in Figures 2–5 (box plots) should perhaps be increased in size.

Finally,
4) The authors discuss something very important for successful plant establishment and growth: "optimal conditions of environmental variables".
This paper would be greatly enriched if the authors would cite other papers related to the optimum and/or optimal range of environmental variables. In essence, the success of plants in a physical space depends to a large extent on the ideal environmental conditions.
There are several recent studies on the definition of optimal values and ranges of different temperature metrics, precipitation variables, and topography variables for forest species. Recent efforts have focused on the use of a probability density function (e.g., Weibull, Gaussian mixture model etc.) to determine how temperature, soil pH, precipitation, and physiography affect occurrence of plant species.

Author Response

Thank you for kind comments.

1) and 2):

The variables were selected by Pearson’s coefficient. And then we calculated Spearman correlation coefficients between these distances and volume growth rankings. It was clarified in the text.

3): graphics will be revised in editing.

4): I found a reference that used Bayesian Generalized Linear Model (BGLM) with abiotic variables, and wrote sentences the future work with our results at the end of the discussion. Also, add a reference [28].

Author Response File: Author Response.docx

Reviewer 3 Report

Dear authors,

The revised manuscript is admissible.

Best regards

 

Author Response

I would like to express my sincere gratitude for taking the time to review our paper. Your insightful feedback has been invaluable in improving the quality of our work.

I clarify the analysis method in M&M. Also, we cited a reference which used Bayesian Generalized Linear Model (BGLM) with abiotic variables, and wrote sentences the future work with our results at the end of the discussion. Also, add a reference [28].

Author Response File: Author Response.docx