Poultry Litter Biochar as a Gentle Soil Amendment in Multi-Contaminated Soil: Quality Evaluation on Nutrient Preservation and Contaminant Immobilization
Round 1
Reviewer 1 Report
this paper is very interesting and the results could be of great inerest, but unfortunately the quality of English is very low, so that the meaning of several sentences is not clear and I was not able to understand many sections of the paper.
Often changes in HM content are discused but it is not clear if this change regards the total content or the bioavailability of HM. I think that treatments can change the bioavailability of metals, while the changes of total content are not justifiable.
I suggest to resubmit the manuscript after a complete rewriting made by a native English speaking.
Several comments are reported through the text in the attached file.
Comments for author File: 
Comments.pdf
Author Response
Dear reviewer:
Thank referee’s valuable comments. We have revised the manuscript carefully and in details based on the valuable comments of reviewers, and have made the presentation and discussion of manuscript more complete. Additionally, according to reviewer’s suggestion “Extensive editing of English language and style required”, the original manuscript has been undergone English language editing by MDPI (English Editing ID: english-39552).
The detailed reply please see the attachment.
bets regards
Author Response File: Author Response.pdf
Reviewer 2 Report
This study investigated the effects of poultry-litter biochar amendment on the availability of heavy metals in a contaminated soil. Poultry litter was pyrolyzed at five different temperatures and the resulting poultry litter biochars were amended to a heavy-metal contaminated soils in different rates. After 56 days of incubation at 60% field water holding capacity, the soils amended with biochars were analyzed for pH, EC, DOC, and the availabilities of nutrients (P, K, Ca and Mg) and heavy metals (Cr, Cu, Ni and Zn). This study has scientific merit but requires revision before accepting it for publication.
- Restructure the first four sentences in the abstract to make the content more concise.
- The introduction provides background information that justifies the use of poultry litter for producing biochars and defines the objectives of this study. Overall, it is well structured.
- Explain why the soils were incubated for 56 days? Any reasons for the selection of the duration?
- Provide the elemental composition of the original poultry litter to be compared with those of the poultry litter biochars.
- In line 155, it was mentioned that the available Cr, Cu, Ni and Zn were extracted with water. This is not consistent with the descriptions in Lines 123, indicating their extractions using 0.1 M HCl and 0.01 M CaCl2.
- Please describe the details of the soil characterization methods, the treatment of the soil samples at the end of the incubation and the collections of soils and soil solutions.
- In addition to the results of the statistical analysis in Tables 2 and 3, the authors should show the measured data of the soil properties and the contents of nutrients and heavy metals.
- The "Conclusions" section requires substantial revisions. It should provide the significant findings of this work and their environmental implications, rather than repeat the descriptions of the results. If possible, please also describe the limitations of this study and the future scope.
Author Response
Dear reviewer:
Thank referee’s valuable comments. We have revised the manuscript carefully and in details based on the valuable comments of reviewers, and have made the presentation and discussion of manuscript more complete. Additionally, according to reviewer’s suggestion “Moderate English changes required”, the original manuscript has been undergone English language editing by MDPI (English Editing ID: english-39552).
The detailed reply please see the attachment.
best regards
Author Response File: Author Response.pdf
Round 2
Reviewer 1 Report
the paper has been improved and is now suitable for publication in Agronomy
Author Response
Dear reviewer:
Thank referee’s valuable comments.
best regards
Author Response File: Author Response.pdf
Reviewer 2 Report
The authors have revised the manuscript according to the reviewer’s comments and suggestions. However, some minor revisions are still required before this manuscript can be accepted for publication.
- Please go through the manuscripts to correct typos and grammatical errors.
- The quality of the figures has to be improved.
Author Response
Dear reviewer:
Thank referee’s valuable comments. We have revised the manuscript carefully and in details based on the valuable comments of reviewers, and have made the presentation and discussion of manuscript more complete.
best regards
Author Response File: Author Response.pdf
