Effect of Two Exogenous Organic Acids on the Excitation Effect of Soil Organic Carbon in Beijing, China
Round 1
Reviewer 1 Report
Review on manuscript: forests-151942
Title: Effect of two exogenous organic acids on the excitation effect of soil organic carbon
1) The title should add “…in the artificial pine forest, Beijing, China”
2) Line 13: “And” should not be at first word of sentence.
3) Introduction part: Before mentioning about “Organic acids are important control factors for soil organic carbon excitation.” The authors should give the general information about SOC. Why SOC is important? The below papers are recommended for citation.
Lal, R. 2011. Sequestering Carbon in Soils of Agro-Ecosystems. Food Policy1, 36 (Suppl. 1), S33–S39.
Arunrat, N., Kongsurakan, P., Sereenonchai, S., Hatano, R. 2020. Soil Organic Carbon in Sandy Paddy Fields of Northeast Thailand: A Review. Agronomy, 10(8), 1061.
Arunrat, N., Pumijumnong, N., Sereenonchai, S., Chareonwong, U. 2020. Factors Controlling Soil Organic Carbon Sequestration of Highland Agricultural Areas in the Mae Chaem Bain, Northern Thailand. Agronomy, 10, 305.
4) Lines 72-73: The map of study (the artificial pine forest in Beijing Songshan National Nature Reserve) is needed.
5) Figures 3-6: The meaning of each treatment should be explained in the methodology or note at the bottom each figure. This is because the reader will have no idea what is “30D_CK3”, “60D_CK1”, so on.
6) Lines 230-233: Why the rise of active carbon content between the two organic acids at the same concentration was not significant? It will be more understanding if you can provide the reason.
7) Line 274: “Howver” should be “However”. Please check the English grammar throughout the manuscript.
8) In Conclusion part: The recommendation for further study is needed.
Best regard,
Comments for author File: 
Comments.docx
Author Response
Dear Editors and Reviewers,
Thank you for your letter and for the reviewers’ comments concerning our manuscript entitled, “Effect of two exogenous organic acids on the excitation effect of soil organic carbon in Beijing, China.” The comments were all valuable and were very helpful for revising and improving our paper, as well as clarifying the significance of our research. We considered the comments carefully and have made corresponding corrections, which we hope will meet with approval. Revised text is marked in blue in the manuscript, and our responses to the reviewer’s comments are as follows.
Point 1: The title should add “…in the artificial pine forest, Beijing, China”
Response 1: Thanks for this valuable advice. I have added “…in the artificial pine forest, Beijing, China” in the title.
Point 2: Line 13: “And” should not be at first word of sentence.
Response 2: I have made corresponding changes in the paper (line 15).
Point 3: Introduction part: Before mentioning about “Organic acids are important control factors for soil organic carbon excitation.” The authors should give the general information about SOC. Why SOC is important? The below papers are recommended for citation.
Lal, R. 2011. Sequestering Carbon in Soils of Agro-Ecosystems. Food Policy1, 36 (Suppl. 1), S33–S39.
Arunrat, N., Kongsurakan, P., Sereenonchai, S., Hatano, R. 2020. Soil Organic Carbon in Sandy Paddy Fields of Northeast Thailand: A Review. Agronomy, 10(8), 1061.
Arunrat, N., Pumijumnong, N., Sereenonchai, S., Chareonwong, U. 2020. Factors Controlling Soil Organic Carbon Sequestration of Highland Agricultural Areas in the Mae Chaem Bain, Northern Thailand. Agronomy, 10, 305.
Response 3: Introduction part: I have added the information on the importance of SOC for studying soil organic carbon mineralization and corresponding references in introduction (lines 35-42).
Point 4: Lines 72-73: The map of study (the artificial pine forest in Beijing Songshan National Nature Reserve) is needed.
Response 4: We carried out the indoor culture experiment to control the influence of interference factors on the possible results to the maximum extent, and the conclusions obtained are objective and reliable. We did not conduct field trials, so we cannot provide the map of study.
Point 5: Figures 3-6: The meaning of each treatment should be explained in the methodology or note at the bottom each figure. This is because the reader will have no idea what is “30D_CK3”, “60D_CK1”, so on.
Response 5: Figures 3-6: I have changed to the images in this paper and explained the meaning of each treatment at the bottom of each figure (lines 211-213).
Point 6: Lines 230-233: Why the rise of active carbon content between the two organic acids at the same concentration was not significant? It will be more understanding if you can provide the reason.
Response 6: I have provided in the article the reasons why the rise in the active carbon content between the two organic acids is not significant at the same concentration (lines 256-266).
Point 7: Line 274: “Howver” should be “However”. Please check the English grammar throughout the manuscript.
Response 7: The spell mistake has been corrected and grammar problems have been checked. (lines 309).
Point 8: In Conclusion part: The recommendation for further study is needed.
Response 8: I have added a further explanation (lines 325-329, 335-337).
Thanks again for your really helpful comments. We have tried our best to improve the manuscript according to your suggestions.
Yours sincerely,
Wei Dai
References:
[1] Lal R. Sequestering carbon in soils of agro-ecosystems - ScienceDirect[J]. Food Policy. 2011, 36(1): S33-S39.
[2] Zhang Z, Cai X Z, Tang C D, Guo J F. Priming effect of dissolved organic matter in the surface soil of a Cunninghamia lanceolata plantation[J]. Acta Ecologica Sinica. 2017, 37(22): 7660-7667．
[3] Arunrat N, Kongsurakan P, Sereenonchai S, et al. Soil Organic Carbon in Sandy Paddy Fields of Northeast Thailand: A Review[J]. Agronomy. 2020, 10(8).
[4] Arunrat N, Pumijumnong N, Sereenonchai S, et al. Factors Controlling Soil Organic Carbon Sequestration of Highland Agricultural Areas in the Mae Chaem Basin, Northern Thailand[J]. Agronomy. 2020, 10(2):305.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
Dear Authors,
Your contribution is of high scientific level, good structured, and with highly valuable output.
Some minimal additional explanations and broader interpretation should be useful.
Some details are herewith below.
Lines 111-113
This section may be divided by subheadings. It should provide a concise and precise 111 description of the experimental results, their interpretation, as well as the experimental 112 conclusions that can be drawn.
Whom this proposition is addressed to?
Lines 249-250
In addition to the above effects, organic acids at high concentrations could significantly 249 increase or decrease the relative abundance of some bacterial groups,...
The statement is of no doubts. But this is too common opinion. Please give the details which follow your research.
Lines 271-274
Although the changing mechanism is still unclear, pyrogallic acid may promote the mineralization process by altering soil pH and strongly affecting the number of bacterial species, richness and homogeneity of species composition (Figure 2). However, the correlation needs further study.
The new studies are needed. However, your hypothesizing is important. It should be useful to apply this approach to other parts of Discussion section.
Line 274
However
Discussion and Conclusions do not contain the information about importance of research for the forestry.
Author Response
Dear Editors and Reviewers,
Thank you for your letter and for the reviewers’ comments concerning our manuscript entitled, “Effect of two exogenous organic acids on the excitation effect of soil organic carbon in Beijing, China.” The comments were all valuable and were very helpful for revising and improving our paper, as well as clarifying the significance of our research. We considered the comments carefully and have made corresponding corrections, which we hope will meet with approval. Revised text is marked in blue in the manuscript, and our responses to the reviewer’s comments are as follows.
Point 1: Lines 111-113. This section may be divided by subheadings. It should provide a concise and precise 111 description of the experimental results, their interpretation, as well as the experimental 112 conclusions that can be drawn.
Whom this proposition is addressed to?
Response 1: The section has been divided by subheadings (119-129).
Point 2: Lines 249-250. In addition to the above effects, organic acids at high concentrations could significantly 249 increase or decrease the relative abundance of some bacterial groups,...
The statement is of no doubts. But this is too common opinion. Please give the details which follow your research.
Response 2: We added the detail. After 60 days of soil proteobacteria and basidiomycete relative richness increased by about 26%, and acidobacteria decreased by about 17% (285-287).
Point 3: Lines 271-274. Although the changing mechanism is still unclear, pyrogallic acid may promote the mineralization process by altering soil pH and strongly affecting the number of bacterial species, richness and homogeneity of species composition (Figure 2). However, the correlation needs further study.
The new studies are needed. However, your hypothesizing is important. It should be useful to apply this approach to other parts of Discussion section.
Response 3: I have added a further explanation (311-321).
Point 4: Line 274.However, discussion and Conclusions do not contain the information about importance of research for the forestry.
Response 4: I have added illustration about the importance of this research for forestry to the paper (341-338).
Specially thanks to you for your helpful comments. We have tried our best to improve the manuscript according to your suggestions.
Yours sincerely,
Wei Dai
Author Response File: Author Response.pdf
Round 2
Reviewer 1 Report
This manuscript can be accepted.
