Effects of Forest Vegetation Restoration on Soil Organic Carbon and Its Labile Fractions in the Danxia Landform of China

Round 1

Reviewer 1 Report

 The Danxia landform is a unique red bed landform in China. The effect of vegetation restoration on soil organic carbon components are still poorly understood. This manuscript selected five different vegetation restoration types, mixed conifer-broadleaf forest, evergreen broad-leaved forest, Chinese fir forest and Bamboo forest to discussed the concentrations and stocks of SOC and its LOC fractions ((dissolved organic C, microbial biomass C and easily oxidized organic C in these vegetation soils and their relationship with soil physicochemical properties and enzyme activities. The manuscript gives a lot of valuable information. Research background is of significance. Some meaningful test results were obtained, which are of reference significance for the ecosystem management. However, the manuscript has the following problems, which must be improved before publishing:

1—In “Abstract”: The abstract of the manuscript can be appropriately shortened so that readers can quickly understand the innovative significance expressed by the author.

2—line 47-48: In the introduction, the authors mentioned the influence of environmental temperature on soil moisture and organic matter content, migration, and pH effect, which is very important. It is also an important factor of stratigraphic evolution. The authors should pay attention to some new achievements published recently. For example, “Cotransport of heavy metals and SiO2 particles at different temperatures by seepage. Journal of Hydrology, 2021, 597: 125771”.

3—Lines 171-176: “Soil moisture was measured by the oven-dry method at 105±2℃” and “The dry weight of litterfall was oven-dried at 80℃”. Why are the temperature choices different in the two cases? Please give a brief explanation.

4—Lines 373-377: The authors thought that “Soil temperature, humidity, soil texture and other environmental factors affect soil microbial activities”. On this point, it is necessary to expound the effect of temperature on soil microstructure and adsorption performance and soil organic matter. 

5—Lines 468-469: “Either too high (＞8.5) or too 468 low (＜5.5) of pH value is not conducive to the growth of microorganisms”. Why? How do pH and temperature affect the migration of substances together?

6—“5. Conclusions”: The conclusion should be written in several paragraphs, especially the previous analysis results should be highly condensed, so that readers can grasp the innovative ideas of the paper.

7-- The manuscript references contain too many Chinese literatures, please delete some unnecessary literatures. In particular, pay attention to some new international developments

Author Response

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Author Response File: Author Response.pdf

Reviewer 2 Report

Comments file is attached herewith

Comments for author File: Comments.pdf

Author Response

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Author Response File: Author Response.pdf

Reviewer 3 Report

1. In accordance with the requirements of the journal, write the “Keywords” in a standardized manner, with the first letter lowercase.

2. The abstract is too verbose, and should be a total of about 200 words maximum. Please be concise.

3. According to journal requirements, write the second-level titles in a standardized manner, with the first letter capitalize.

4. In the "Materials and Methods" section, the “soil collection at 0-30 depth” should be added unit.

5. The writing of some units in the text is not standardized. For example, the unit of temperature should be changed to "The New Roman" format. Please check the full text.

6. The "10-cm" and “4-cm” should be changed to "10 cm" and “4 cm” in the "Materials and Methods" section.

7. why the activities of three enzymes (invertase, catalase and cellulase) were measured, but not the others?

8. Please standardize the format of references. For example, the journal name is not abbreviated in reference 4, 5, 6, 7. Please check the full text.

Author Response

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Author Response File: Author Response.pdf

Round 2

Reviewer 3 Report

Based on the author's revision, this article can be accepted.