Characterization of Soil Microbial Biomass Carbon and Nitrogen in Four Forest Types of Shushan Urban Forest Park

Round 1

Reviewer 1 Report

This research investigated the effects of forest stands and soil properties on soil MBC and MBN in urban forest ecosystems. The research topic is suitable for Forests. However, the similar results can be found in many studies, so the research is not novel and readers are unable to obtain new knowledge from this manuscript. I suggest adding new content to improve the readability of the manuscript. Specific Comments: Line142-151 The sample plot is pseudoreplication, which may affect the conclusion. Microbial biomass is significantly influenced by seasons. What are the main factors to consider when collecting soil samples in May and January. Line 156-162 Usually, air dried soil is used to evaluate organic carbon concentration, and what is the basis for using 105℃ drying soil in this manuscript? Specific testing methods require additional references. Line 168-169 How to ensure a temperature of 25 ℃? Usually, we do not control the temperature when measuring microbial biomass. Line186-202 In the statistical analysis section, it is recommended to increase the statistical results of the impact of forest types and soil layers on soil properties and microbial biomass.

 

Author Response

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Reviewer 2 Report

The authors studied the effects of different urban forest types on soil microbial carbon and nitrogen and tested the relationship between soil microbial carbon/nitrogen and soil physicochemical properties in an urban forest park. This study focuses on the urban ecosystem which is rarely a concern before, but recently more and more studies have put focus on this important system. Although the research methods and scientific hypotheses of this study are not so novel compared to former studies on natural terrestrial ecosystems and agricultural ecosystems, it is at least a complement to urban ecosystem research.

 

Specific comments:

Abstract：

The structure of the abstract should be adjusted to adapt to the general format of the Forest journal. Furthermore, the sentence in lines 13-14 is repeated in lines 17-19, authors should recheck and remodel them.

The overall logic of the introduction is acceptable, however, this introduction should be improved. For example, In the first paragraph, the authors show that urban forests are well worth studying, this is a general topic, however, the specific Shushan park is then introduced in detail. This is just like a very big tree bearing a very small fruit. Logically, you should give a scientific question about Shushan Park in the following text, but the importance of soil microbes is given in the next paragraph, which is another very big general topic. I suggest the authors move the description part of Shuan Park to the last paragraph, stating that this park is a typical study site which is helpful to solve the knowledge gaps that the authors showed before, and then pull out your specific objectives.

Format:

Generally, there should be a blank between the number and unit, for example, “70cm to over 100cm” in line 126 should be “70 cm to over 100 cm”, please check the full text and modify the same format issues.

 Methods:

Line 187, “one-way ANOVA was used to evaluate differences between different treatments”, “treatment” is not suitable here, authors never introduced what treats were applied, and the vocabulary “treatment” was only used here which is neither used in the result nor discussion sections. I suggest authors used “vegetation types” instead of “treatments” here.

Line 188, please specify which “two groups”?

Line 192-193, the sentence"considered "highly significant". s. " Please make sure is the “s.” redundant or not.

Line194-195, The normality of variables was tested before correlation analysis, however, the normality of variables also needed to be tested before ANOVA, were the authors do it before ANOVA?

 Figures and tables：

Figure 1, The study area in the right panel is not clear, please set the rectangle border in color with clearer contrast, such as black.

Table 1, The full name of each quadrat should also be shown in the note of this table.

Table 2 and Table A1, Why the units of SOC and TN g/kg while the unit of TP is mg/g. They should be in a unified form.

Table 2 and Table A1, A2, what’s the meaning of numbers in these tables, are they referring to mean±sd or mean±se?

Figure 2, 1). The x-axis title is wrong. The tile showed that panels (a) and (b) are MBC and MBN in the growing season, but the x-axis title of the panel (b) is “Dormant season”. Please check it and modify it. The same problem and suggestion to panels (c) and (d). Furthermore, the x-axis should be soil layers not seasons. you can show the seasons on the top of each panel, or just change the y-axis to, for example, "Growing season MBC (mg/kg)".

Figure 2 title, What does the bar and error bar mean, and what is the meaning of different letters? The full name of MBC and MBN should be specified.

Figure 3, How to separate the r-value and p-value in the same panel, for example, I don’t know which r-value and p-value belong to the growing season. The full name of each variable (excluding pH) should be given. The same to Figure 4.

Table A2, Values with different lowercase letters (a, b, c) in the SAME ROW indicate significant differences (P<0.05) based on a way ANOVA followed by Fisher's LSD test. I am confused about the same row, Aren't the differences compared among different forests, why does the author say the different letters in the same row indicate significant differences?

Author Response

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Reviewer 3 Report

Although the presented research falls within the scope of research on soil-plant-microorganism relationships, it brings a new perspective on these relationships in the case of plantation forests. The Authors analyze changes in the physicochemical properties of the soil, in the cycles of nutrient circulation and indicate the importance of microorganisms in the functioning of forest ecosystems. The presented research can be used, as the Authors emphasize, in forest management planning.

Line 91: It is not necessary to provide a significance level: Li et al. [30] also found a significant positive correlation 90 between MBC, MBN, and soil moisture (P<0.05). Furthermore, MBN was positively related to SOC, soil total phosphorus, and available phosphorus [31].

Lines 107-111: It would be worth summarizing the research objectives with a hypothesis/hypotheses

line 120: Figure 1 should be quoted earlier in the description of the research site, e.g. line 117

 

Line 145: [31] described by whom?

Line 241, Table 2 - please explain in the title of the table the abbreviations PM, QA, LF, DB , the same in the case Figure 2 (line 304)

Line 344: please explain in the title of Figure 3 the MBC abbreviations; EC; SWC; SOC; TN; TP. The same in the case of Figure 4 (line 352)

Line 389: Please explain in the title of Figure 5 the abbreviations MBC, MBN, PM, QA, LF, DB.

Line 501: Conclusions - In this part of the text, the Authors refer to the hypotheses that could be made.

Comments for author File: Comments.pdf

Author Response

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Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

The author has made revisions to the manuscript, and I have no further comments.