Soil Amendment with a Lignite-Derived Humic Substance Affects Soil Properties and Biomass Maize Yield
Round 1
Reviewer 1 Report
The study shows the effect of using a lignite-derived humic substance (Act) to improve soil properties and biomass yield.
The work is comprehensive but requires some editing.
The title of the paper should include the source of the humic substance as lignite-derived and should be revised.
The abstract should be rewritten. In its current form, it is very difficult to follow.
The discussion section should also include some environmental implications of adding Act on soil from relevant literature. For example, how it may impact the microbial community, C mineralization, and also P leaching.
While recommending Act2, the author should write about adding too much P into the soil.
The pot experiment is for two years, and it is difficult to draw such strong conclusions from it. The author should discuss it.
Section 2.2 is not clear and should be rewritten
I am also attaching the annotated version of the pdf with some comments to address
Comments for author File: 
Comments.pdf
Author Response
We are grateful for a thorough review of our paper and reviewers comments and suggestions. We answered all questions and included all concerns of reviewers which improved substantially our manuscript. Our manuscript was proof-read by a Cambridge Proof-Reading Service and we include a certificate at the end of the cover letter. All corrections following Reviewers suggestions are marked in red in the manuscript. The whole text was corrected by the native speaker from Proof-Reading Service but these changes are not marked in order to make it more transparent and understandable.
All answers are below:
Reviewer 1
The study shows the effect of using a lignite-derived humic substance (Act) to improve soil properties and biomass yield.
The work is comprehensive but requires some editing.
The title of the paper should include the source of the humic substance as lignite-derived and should be revised.
Done
The abstract should be rewritten. In its current form, it is very difficult to follow.
It was rewritten according to your indices.
The discussion section should also include some environmental implications of adding Act on soil from relevant literature. For example, how it may impact the microbial community, C mineralization, and also P leaching.
A section: Environmental implications of adding Actosol to soils was added to Discussion: Lines 495-515
While recommending Act2, the author should write about adding too much P into the soil.
The info about risks linked to adding too much phosphorous was included: Lines 484-487
The pot experiment is for two years, and it is difficult to draw such strong conclusions from it. The author should discuss it.
Conclusions drawn after two year experiment have been weakened: Lines 535-536
Section 2.2 is not clear and should be rewritten
Section 2.2. have been rewritten. Lines 89-133
I am also attaching the annotated version of the pdf with some comments to address
All suggestions from the text have been taken into account and corrected.
Reviewer 2 Report
Comments for author File: Comments.pdf
Author Response
We are grateful for a thorough review of our paper and reviewers comments and suggestions. We answered all questions and included all concerns of reviewers which improved substantially our manuscript. Our manuscript was proof-read by a Cambridge Proof-Reading Service and we include a certificate at the end of the cover letter. All corrections following Reviewers suggestions are marked in red in the manuscript. The whole text was corrected by the native speaker from Proof-Reading Service but these changes are not marked in order to make it more transparent and understandable.
All answers are below:
General comments for the article entitled “Soil amendment with a humic substance affects soil properties 2 and biomass maize yield". The article is interesting. The introduction covers the current bibliography on the subject and sets out clearly the research questions. Materials and methods are well described and the results are presented clearly.
The discussion could be more extensive with more references to other researchers.
It was enlarged, a new section was introduced: Environmental implications of adding Actosol to soils: Lines 495-515
In lines 323-326 which is the criterion to select these parameters for SQI? Why do not also include DHA from PC1?
DHA was included in SQI calculation, but by mistake it did not appeared in the equations. The equations have been corrected. We apologize for the errors. Lines 335-339
Some other corrections
Lines 37 and 39: you can add also some other references not only in polish language
Other two foreign language references were added: Lines 37 and 40
Line 138: delete “(Tan, 2005)”.
Done
In Table 5: correct “varaition” with “variance” and “cumulative varition” with “cumulative variance”
Corrected
Line 328: delete “2017”
Done
Figure 5 should be improved
Done
Reviewer 3 Report
The effect of Actosol on soil properties and maize yields was investigated by pot experiment and compared with other treatments. The overall experimental design is reasonable, and the data processing is also standardized. However, I have several concerns
1、In section of Abstract, many sentences are not grammatically smooth or incorrect. Similar situations occur in many other parts of the manuscript. It is recommended that the authors revise the text and syntax of the full text.
2、Line77, Actosol used in the research should be marked in the manuscript with the name of the company purchased in manuscript, not just listed in the reference.
3、Whether the matrix soil has been equilibrated for a period of time after the base soil mixing with the treated materials? If yes, it should be stated in the material and method section. If not, why?
4、Line 130, maize shoots and roots from each pot were dried initially in air, and then in a hot-air dryer at 70oC. How long is the drying time? Is the drying time of each treatment consistent? Is the weight constant? Because it has a greater impact on the results.
5、I think one of the obvious shortcomings of this study is that it did not provide pictures of the growth of corn after treatment (such as growth status, plant height, root length, etc.). If there is such information, it is recommended to add it to the manuscript.
Author Response
We are grateful for a thorough review of our paper and reviewers comments and suggestions. We answered all questions and included all concerns of reviewers which improved substantially our manuscript. Our manuscript was proof-read by a Cambridge Proof-Reading Service and we include a certificate at the end of the cover letter. All corrections following Reviewers suggestions are marked in red in the manuscript. The whole text was corrected by the native speaker from Proof-Reading Service but these changes are not marked in order to make it more transparent and understandable.
All answers are below:
The effect of Actosol on soil properties and maize yields was investigated by pot experiment and compared with other treatments. The overall experimental design is reasonable, and the data processing is also standardized. However, I have several concerns.
1.In section of Abstract, many sentences are not grammatically smooth or incorrect. Similar situations occur in many other parts of the manuscript. It is recommended that the authors revise the text and syntax of the full text.
Abstract was corrected and the whole article was proof-read by Cambridge Proof-reading Service: Lines 12-24
2.Line77, Actosolused in the research should be marked in the manuscript with the name of the company purchased in manuscript, not just listed in the reference.
Done, Line 78
3.Whether the matrix soil has been equilibrated for a period of time after the base soil mixing with the treated materials? If yes, it should be stated in the material and method section. If not, why?
After mixing with additives soil has been equilibrated for seven days: Lines 107-108
4. Line 130, maize shoots and roots from each pot were dried initially in air, and then in a hot-air dryer at 70oHow long is the drying time? Is the drying time of each treatment consistent? Is the weight constant? Because it has a greater impact on the results.
The missing information about drying have been added: Lines 131-133
After harvesting the roots and aboveground parts of the maize were dried in a drier at 70oC. The roots were dried for 24 h and the aboveground parts for 48 h.
5. I think one of the obvious shortcomings of this study is that it did not provide pictures of the growth of corn after treatment (such as growth status, plant height, root length, etc.). If there is such information, it is recommended to add it to the manuscript.
The study does not covered detailed biometric analyses. We only have pictures of maize of different treatments taken in the phase of 7th leaf that we are including them in the article together with the description of differences in maize growth between treatments – Figure 6
Round 2
Reviewer 1 Report
Thank you for editing the manuscript.
Reviewer 3 Report
The author made a comprehensive revision of the text and grammar, and answered the questions I raised, and suggested accepting the publication
