Vegetation Degradation of Guanshan Grassland Suppresses the Microbial Biomass and Activity of Soil
Round 1
Reviewer 1 Report
The abstract in general doesn't appropriately capture the goals and result of the presented paper.
The abstract is not well composed right from the introductory sentences. A thorough revision of the abstract is needed.
The introduction section seems okay. However, I find the goals of the study as stated in this section, confusing.
Line 76 – 79: “Therefore, the goals of this research were to: (i) determine the variations in soil physico-chemical properties and microbial parameters following vegetation degradation, and (ii) explore the potential mechanisms of vegetation degradation and soil processes in the Guanshan grasslands.”
Could you please state clearly what the variations were in respect to (time and/or vegetation type)?
The study area was without a photo. Could you please add a photo of the site under study?
I think table 1 should be well structured and pushed to 2.1.
The experiment procedures (2.3; 2.4; 2.5) are not well composed? I suggest a step by step form to make it more understandable and easier to read.
Could you please provide brief explanation to figure 7 and explain a, b and c used in 3.1?
The paper is poorly discussed and needs a thorough revision by adding previous studies. Although the conclusion part is well done and clear, I find the study duration too short hence the outcome may not be justified. Could you please throw more light on the chosen duration of just two months?
The paper makes interesting reading and important, but it is marred by the poor English and suggest a complete revision is done.
Author Response
Response to Comments
Dear Reviewer:
Thank you for your comments concerning our manuscript entitled “Vegetation degradation of the Guanshan grasslands suppresses soil microbial biomass and activities” (ID: land-1098368). Those comments are all valuable and very helpful for revising and improving our paper, as well as the important guiding significance to the research. We have studied comments carefully and have made correction which we hope meet with approval. The main corrections in the paper and the responds to Editors and the reviewer’s comments are as following:
Reviewer 1#:
1.Comment:
The abstract in general doesn't appropriately capture the goals and result of the presented paper. The abstract is not well composed right from the introductory sentences. A thorough revision of the abstract is needed.
Response
DONE. We have corrected them by Reviewers’ good suggestions. (L14-31)
2.Comment:
The introduction section seems okay. However, I find the goals of the study as stated in this section, confusing. Line 76 – 79: “Therefore, the goals of this research were to: (i) determine the variations in soil physico-chemical properties and microbial parameters following vegetation degradation, and (ii) explore the potential mechanisms of vegetation degradation and soil processes in the Guanshan grasslands.”Could you please state clearly what the variations were in respect to (time and/or vegetation type)?
Response:
DONE. We are very sorry for our incorrect writing that we have corrected it. (L86, L87)
- Comment:
The study area was without a photo. Could you please add a photo of the site under study?
Response:
Your suggestions are very good for revising our manuscript. Unfortunately, we have not the photo. Because we did not take photos of the experimental plots when we did our experiments. Moreover, Guanshan scenic area is closed from December to March in every year. So we could not take photos of the experimental plots now.
- Comment:
I think table 1 should be well structured and pushed to 2.1.
Response:
DONE. We have corrected them by Reviewers’ good suggestions. (Table 1)
- Comment:
The experiment procedures (2.3; 2.4; 2.5) are not well composed? I suggest a step by step form to make it more understandable and easier to read.
Response:
DONE. It is really true as Reviewer suggested that we have added some formulas (L159-166) and a schematic diagram of the experimental design (L124-136) to make it more understandable and easier to read by the comprehensive suggestions from you and Reviewer 4.
- Comment:
Could you please provide brief explanation to figure 7 and explain a, b and c used in 3.1?
Response:
DONE. We are very sorry for our unclear writing that we have revised them. (L372-376, Table 2 and Fig.2-7)
- Comment:
The paper is poorly discussed and needs a thorough revision by adding previous studies. Although the conclusion part is well done and clear, I find the study duration too short hence the outcome may not be justified. Could you please throw more light on the chosen duration of just two months?
Response:
DONE. We are very sorry for our unclear writing that we have revised them (All red marks in discussion). We have some dates in October 2016, which showed the similar rule with April and July 2017, too. Because too much dates made our manuscript complicated. Thus, we showed just two months.
- Comment:
The paper makes interesting reading and important, but it is marred by the poor English and suggest a complete revision is done.
Response:
DONE. It is really true as Reviewer suggested that the whole manuscript is revised by MDPI English editing and tried to avoid any grammar or syntax error. We hope that the language is now acceptable for the next review process.Special thanks to you for your good comments.
We tried our best to improve the manuscript and made some changes in the manuscript. These changes will not influence the content and framework of the paper.
We appreciate for Reviewers’ warm work earnestly, and hope that the correction will meet with approval. If you think we didn't perform well, please let us know and we will amend it.
Once again, thank you very much for your comments and suggestions.
Yours sincerely,
Yanmei Liu
Author Response File: 
Author Response.docx
Reviewer 2 Report
Dear authors, thank you for accepting all my suggestions and explaining them. The article needs minor changes in the text of the article. Try to better edit the text of the column "Vegetations coverage" in Table 1, so that the name of that column is not written in three lines. I want to point out to you that there are some technical errors in the article. After page 6, the logo of another journal and the abbreviated name of that magazine (Remote Sens.) appear. Also after page number 6 the order of page numbers is disturbed or incorrect.
In line L 285 it says (all –r> 0.96, p <0.05), it should be written (all r = -0.96, p <0.05). Instead of p <0.05, you can also write the exact amount of p values, for example p = 0.003. Instead of (all r2> 0.94, p <0.05) you should write r = 0.94, p <0.05) or put the correct amount instead of p.
Best regards.
Reviewer
Author Response
Response to Comments
Dear Reviewer:
Thank you for your comments concerning our manuscript entitled “Vegetation degradation of the Guanshan grasslands suppresses soil microbial biomass and activities” (ID: land-1098368). Those comments are all valuable and very helpful for revising and improving our paper, as well as the important guiding significance to the research. We have studied comments carefully and have made correction which we hope meet with approval. The main corrections in the paper and the responds to Editors and the reviewer’s comments are as following:
Reviewer2#:
- Comment:
Try to better edit the text of the column "Vegetations coverage" in Table 1, so that the name of that column is not written in three lines.
Response:
DONE. We have corrected them by Reviewers’ good suggestions. (Table 1)
- Comment:
I want to point out to you that there are some technical errors in the article. After page 6, the logo of another journal and the abbreviated name of that magazine (Remote Sens.) appear. Also after page number 6 the order of page numbers is disturbed or incorrect.
Response:
DONE. We are very sorry for our unclear writing that we have revised them.
- Comment:
In line L 285 it says (all –r> 0.96, p <0.05), it should be written (all r = -0.96, p <0.05). Instead of p <0.05, you can also write the exact amount of p values, for example p = 0.003. Instead of (all r2> 0.94, p <0.05) you should write r = 0.94, p <0.05) or put the correct amount instead of p.
Response:
DONE. The r values of soil enzymatic activities and BR with soil depth in east slope have eight and the r values of soil enzymatic activities and BR with soil depth also have eight in west slope, meaning a total of 16 values of r. Similarly, the p values also have sixteen values. The r and p of qCO2 with soil depth have two values, respectively. One is east slope, the other is west slope. Thus, r and p values in our manuscript were written (all r< - 0.96, p < 0.05) and (all r> 0.97, p < 0.05). (L338)
Special thanks to you for your good comments.
We tried our best to improve the manuscript and made some changes in the manuscript. These changes will not influence the content and framework of the paper.
We appreciate for Reviewers’ warm work earnestly, and hope that the correction will meet with approval. If you think we didn't perform well, please let us know and we will amend it.
Once again, thank you very much for your comments and suggestions.
Yours sincerely,
Yanmei Liu
Author Response File: Author Response.docx
Reviewer 3 Report
The authors have done a thorough job of responding to my comments and suggestions on the original manuscript. I appreciate the efforts they took to improve their manuscript. At this point I only have one significant edit to suggest. At several points in both the results and discussion sections (line 188, line 241, legends for figures 4 and 5) the authors refer to the effect of vegetation types on various measured indices. While I know that the authors do have a solid case for thinking that the differences measured across the three vegetation types are due to the differences in vegetation this design did not actually test that theory. To test the effect of vegetation type ideally they would have degraded and intact vegetation types at each elevation to compare. Given the study design and with the goal of avoiding the "correlation is not causation" paradox I would recommend carefully wording their arguments in terms of patterns in soil characteristics associated with each vegetation type rather than characteristics affected by vegetation type. One could argue that the soil metrics measured are more a result of elevation than vegetation. I am not saying that their conclusions are incorrect- they have a solid argument but just that they should be careful to make sure they do not overstate their findings as that can weaken an otherwise plausible theory.
other minor suggestions
lines 41-42 add an indication of the timelines for each dynasty referenced for those of us less knowledgeable about Chinese political history
lines 352 and 398- make these statements a little less definitive- for example the comprehensive results of these factors may have resulted in...
Author Response
Response to Comments
Dear Reviewer:
Thank you for your comments concerning our manuscript entitled “Vegetation degradation of the Guanshan grasslands suppresses soil microbial biomass and activities” (ID: land-1098368). Those comments are all valuable and very helpful for revising and improving our paper, as well as the important guiding significance to the research. We have studied comments carefully and have made correction which we hope meet with approval. The main corrections in the paper and the responds to Editors and the reviewer’s comments are as following:
Reviewer3#:
1.Comment:
At several points in both the results and discussion sections (line 188, line 241, legends for figures 4 and 5) the authors refer to the effect of vegetation types on various measured indices. Given the study design and with the goal of avoiding the "correlation is not causation" paradox I would recommend carefully wording their arguments in terms of patterns in soil characteristics associated with each vegetation type rather than characteristics affected by vegetation type.
Response
DONE. It is really true as Reviewer suggested that we have revised them. (L206, L225-226, L249-250, L279-280,L283-284, L316, L363, L386, L390)
2.Comment:
lines 41-42 add an indication of the timelines for each dynasty referenced for those of us less knowledgeable about Chinese political history.
Response
DONE. We have corrected them by Reviewers’ good suggestions. (L46-47)
- Comment
Lines 352 and 398- make these statements a little less definitive- for example the comprehensive results of these factors may have resulted in...
Response
DONE. We have corrected them by Reviewers’ good suggestions. (L416, L451)
Special thanks to you for your good comments.
We tried our best to improve the manuscript and made some changes in the manuscript. These changes will not influence the content and framework of the paper.
We appreciate for Reviewers’ warm work earnestly, and hope that the correction will meet with approval. If you think we didn't perform well, please let us know and we will amend it.
Once again, thank you very much for your comments and suggestions.
Yours sincerely,
Yanmei Liu
Author Response File: Author Response.docx
Reviewer 4 Report
Abstract: The abstract is unclear and does not properly encapsulate the aim and outcome of the study.
The introductory texts " Vegetation variation acts as one of the principal forms of degraded grassland. A 14 gradient of vegetation degradation was found from high to low altitudes in Guanshan 15 grasslands in the order of forest grassland (FG) < shrub grassland (SG) < herb grassland (HG)." is unclear
I recommend a short introductory text connecting grassland vegetation degradation to microbial activities, then some information on the state Guanshan grasslands necesitating the research. Then you can clearly state what the study sought to do, the outcome etc.
Introduction:
Line 67 - 68: Could you please provide citation for the statement "Although the effects of degraded vegetation on soil microbial properties have been reported in many areas"
The goals of the study are unclear. Variations with respect to time (and what time interval) or grassland type?
Materials and Methods
2.1 Study area: I suggest a site picture is added and "Table 1 The information of geographic and vegetation in the study sites of Guanshan grasslands." in 2.2 converted into concise text and pushed to 2.1
2.2 Experimental design and soil sampling collection: I suggest a schematic diagram of the experimental design is added
2.3, 2.4, 2.5: I suggest changing the subheadings to "Physico-Chemical Analysis, Soil microbial biomass analysis" etc. Also, could you please clearly describe the analysis procedure in a stepwise manner with all the equations that come with it as the current texts seem clumsy and difficult to comprehend?
2.5. Statistics analysis: Firstly, please check the numbering as 2.5 appears twice.
Line 156 - 157: Which vegetation types are being referred to here? Could you please clearly specify them?
3. Results
3.1 Table 2: Letters a,b and c are not explained?
Illegible labelling for Fig 1 - 6. Could you please explain fig 7?
4. Discussion
4.2 and 4.3: Not well discussed as these sections do not compare findings with similar studies
5. Conclusion: The section is clear and concise
The science and aim study are relevant and justified especially as you seldom find studies connecting vegetation variations to soil factors. However, aside the numerous grammar inaccuracies throughout the entire paper, taking samples in just two separate months is not enough.
I suggest a thorough revision is done and proper justification given for choosing just two months
Author Response
Please see the attachment
Author Response File: Author Response.docx
Round 2
Reviewer 1 Report
Most of my concerns raised have duly been addressed.
Although, I still find the discussion part not well revised, I appreciate the thorough revision done by the authors hence find the current version of the manuscript publishable after minor adjustments of the manuscript text presentation are done (gaps, uniform fonts etc.)
Reviewer 4 Report
The author has modified the manuscript substantially. all the comments are addressed. I recommend accepting the manuscript in its current form.
This manuscript is a resubmission of an earlier submission. The following is a list of the peer review reports and author responses from that submission.
Round 1
Reviewer 1 Report
The paper presents an interesting issue and the question of how degradation of vegetation impacts the soil microbial community and potential feedbacks to vegetation is an important one. The current manuscript is unclear on a couple of key elements that I feel are essential to understanding the results presented. First the question of degradation. The authors present the study gradients as gradients of degradation ranging from the high-elevation forest grasslands which are assumed to have low levels of degradation to the lower-elevation herbaceous grasslands which are considered more degraded. There is a short statement in the discussion about how the herbaceous grasslands are closer to the road and affected by over-grazing and trampling (lines 334-337) but that is insufficient. The authors should clearly explain the land uses for all sites as well as what expected natural vegetation cover would be for all much earlier in the paper (in the site and methods section). The type and frequency of disturbances causing the degradation are important as is the method used to assess degradation. According to Table 1 both the FG and HG sites had approximately 70% coverage while the shrubland had much more sparse vegetation coverage. Without this information it is hard to know how much of the differences measured are attributable to the elevation change and shift in community structure and how much could be attributed to degradation.
In the Introduction (lines 39-44) you define vegetation degradation as a "reductions in coverage, species composition, and aboveground vegetation biomass ; low plant productivity, soil organic carbon (C) and nutrients [e.g., total nitrogen (N), total phosphorus (P), available P and inorganic N]; moisture loss weaker soil aggregate stability; high soil erosion; and drastic changes in soil temperature" It seems to me that vegetation degradation really only includes coverage species composition biomass and productivity. The rest of the list are soil characteristics that could result from vegetation degradation. It would make the paper much stronger to clearly define vegetation degradation- potential drivers both human activities as well as other drivers and the potential effects on soil properties, You could even include a brief discussion of how different drivers (fire, grazing drought etc) have different degrees of impact or affect different aspects of vegetation.
I was also confused a bit by Table 1 in that it appeared that there were two distinct descriptions for the FG and SG sites but only one for the HG. These were not identified as east or west slopes and it was unclear how this fit into the sampling design described so it would help to have that explained.
Finally if I understood the methods section correctly there are five plots for each treatment (FG SG and HG) on each transect and the samples from each of the five plots were composited by depth so that you have a maximum n of 2 for statistical analysis by depth which may be a problem. If you collected multiple samples from each plot and composited them only within the sample plot then you would have an n of 5 per treatment and transect which would be statistically much stronger. Please clarify what the n was for your statistical analysis.
Less critical but still points that should be addressed include"
line 82 and Table 1 you use the word arbors when I think you mean trees
Methods section- all the analytical methods used for soil properties should be appropriately referenced
qCO2 should be defined in the introduction
line 264 RDA should be fully spelled out with the abbreviation in parentheses the first time it appears in the text
Reviewer 2 Report
Dear authors, these are my comments:
Line 13: rephrase the sentence, reorganize it, you mention twice time degradation, which is confusing.
Line 20-22: sentence beginning with “The results that FG and SG….”, it is necessary to reformulate it to be clearer and more constructive.
Line 26-27, "causing degradation of the Guanshan grassland ecosystem", isn't it in itself already degraded. Unclear conclusion! Better rephrase this part of sentence.
Other comments
Are there any data on erosion and surface runoff in the study area? If so, include them in the discussion or in the description of the research area.
Is the same soil type in FG, SG and HG? If not, it also affects the activity of microorganisms.
Line 65-72, is there any reference condition without degradation to compare degraded and non-degraded grassland? Maybe there is some data in the literature, so use that for discussion.
Line 78-81, for climate data and climate elements need to add a reference or are these the results of your field measurements?
Line 81, “evaporation is low“, whay low when it is higher than amount of precipitation?
Line 95, How many test plots did you have in the field in total? Are 5 plots in each case (5 for FG, 5 for SG and 5 for HG) or 5 plots in total?
Table 1, How you estimate vegetation coverage? Add data on soil type (s) to Table 1
Is there data on the plant community instead of listing the dominant species (column of dominant species)?
Line 108-109, add references to Kjeldahl method is alkaline diffusion method!
Line 110-112, quote working methods!
In chapter Soil microbial biomass, add quotes of methods used!
Line 151, move the sentence to the end of the statistical analyzes chapter and have both software you used in the same sentence.
How many repetitions did you have in the field (5?) And how many in the laboratory (3?)
Line 159, what was the significance limit for correlations? Same p <0.05?
I suggest a better technical arrangement of the chart - picture. In some images, the text, units of measurement and numbers on the y scale are barely visible. I also suggest better technical arrangement, filling in the blank space on page 7.
In Table 2, the data n = 3 confuses me. Did the authors mix rehearsals and number of samples?
Line 205, in addition to the amount of the correlation coefficient r, add the value of p
What was the sample size n correlated?
Line 248-249, it is not seen in the tables how much the enzyme activity at the western exposure is less than the eastern exposure. Only significance is seen.
Line 250, please add a minus sign in front of r, if the correlation is negative.
Line 272, add to the correlation coefficients r and the amount p.
Line 299, Ref., Error?
Perhaps Figure 7 should be moved to the Results chapter.
In general for the discussion of chapter 4.1. If HGs are used to graze animals, it should be discussed how animals living in herds change not only the physical appearance of the environment (if animals are present in large numbers) but they also change the physical, chemical properties of the soil, and the soil microclimate.
Line 354-356, why use the term "shalow slope" when line 86-87 uses the term low and high slope?
Line 393, “smaller slope“, is this correct ?
You did not show the results (data) on soil moisture anywhere, and you determined it gravimetrically !!
In the conclusions section, please be more specific. There are also some generally known things there such as a decrease in microbiological activity with soil depth.
Best regards.
Reviewer
Reviewer 3 Report
The manuscript titled “ Vegetation degradation suppresses soil microbial biomass and microbial activities in the Guanshan grasslands“. I find the idea interesting and in line with the aim of the journal. I have some concerns on the experimental set-up to justify what the authors claim. Moreover, the rationale behind some of the data presented was not entirely clear. I also recommend to the authors to improve their references by conducting a more extensive review on international literature. Particularly, in the introduction statements are not supported by the references selected by the authors. The logic of some sentences is also questionable. Below are my point to point analysis of manuscript.
- I suggest to modify the title title should be more crisp and brief.
- Introduction is very short it should reflect the proper background of study, which I find is missing.
My main concern of a manuscript is the statical test.
what is the value of n while calculating ANOVA? Author mention n= 3
n Value (3) used in the manuscript is too few to examine normal distribution of variables in sample, however, Shapiro-Wilk test is appropriate for samples from 3 to 5000 but for lesser value of n it receives non-normal distribution. Thus ANOVA that is parametrical test is incorrect for such small samples.
Author should mention the data set that do not pass the normality test.
What method was used in exponential transformation, if it was done with the help of software mention the name of software.
Secondly, the error bar in the figure should correspond to the CI . I highly recommend to use confidence interval instead of Standard deviation, in the error bar.
I have doubt with the stat done as the statistic is the back bone of any research study.
- Highlighting the data set that donot follow the normal distribution
- Explaining how ANOVA was calculated for non normal distribution.
Although the study is interesting and could be useful for a certain group of the scientific community, therefore, I would suggest improving the manuscript, giving a chance for the next round, because the subject is interesting
