Iron-Doped Biochar Regulated Soil Nickel Adsorption, Wheat Growth, Its Physiology and Elemental Concentration under Contrasting Abiotic Stresses
, Rabia Shaukat 1, Muhammad Ansar Farooq 3, Muhammad Nadeem Ashraf 4,5, Faisal Nadeem 6, Mohsin Tanveer 2, Yasir Hamid 7 and Nan Sun 4,*
Round 1
Reviewer 1 Report
This paper is well written and discussed. Only my suggestion is if the authors can perform Real-time PCR on how BC affects some abiotic induced gene markers before and after the treatment to the wheat growth, then it will give more strength to this paper
Author Response
Comment: This paper is well written and discussed. Only my suggestion is if the authors can perform Real-time PCR on how BC affects some abiotic induced gene markers before and after the treatment to the wheat growth, then it will give more strength to this paper
Response: Thank you for the compliments and valuable suggestions. We shall definitely consider qPCR experiments for future research. We do hope that the respected reviewer would kindly agree with it.
Reviewer 2 Report
Dear Authors,
the article focuses on “Iron-doped biochar regulated soil nickel adsorption, wheat growth, its physiology and elemental concentration under contrasting abiotic stresses”.
The paper is not satisfactory written, needs a careful editing, fonts, and style. However, it is recommended:
- Reformulate the abstract by telling prospective readers what you did and what the important findings of your research were.
- Introduction and, above all, the Conclusion can be improved in order to show better aim and results for further studies in the topic.
- Please provide more quantitative key contributions of the study with proper discussions, highlight the limitations of this study and the future work.
Author Response
DearAuthors,
the article focuses on “Iron-doped biochar regulated soil nickel adsorption, wheat growth, its physiology and elemental concentration under contrasting abiotic stresses”.
Comments: The paper is not satisfactory written, needs a careful editing, fonts, and style. However, it is recommended:
- Reformulate the abstract by telling prospective readers what you did and what the important findings of your research were.
- Introduction and, above all, the Conclusion can be improved in order to show better aim and results for further studies in the topic.
- Please provide more quantitative key contributions of the study with proper discussions, highlight the limitations of this study and the future work.
Response: Thank you for your review and comments. Paper formatting was done according to Journals’ authors guide. The abstract was rewritten. Please see lines 33-43. The introduction and conclusion have been improved. Please see the highlighted and tracked changes in Introduction and conclusion sections. Similarly, the discussion has been modified as per suggestion. A separate paragraph has been added related to the economics and limitations of biochar. Please see heading 4.6 in the discussion section.
Reviewer 3 Report
This manuscript describes the results of pot experiments where iron enriched biochar is tested as soil amendment able to mitigate the negative effects of abiotic stress for wheat plant.
The topic fits the scope of the journal, the results are quite predictable, but could be of certain interest.
The experiments seems to be well conducted but the treatments are presented ambiguously:
· Line 125-131: Each pot of twelve treatments was filled out with 4 kg of bhal soil. BC (1%) was applied to all pots (except control), homogenously by mixing it with soil and, after this for treatments description: The experimental set up was in triplicates having different materials BC (1%), Ni (0.5 mM NiNO3), Na (100 mM NaCl) and CO3 (100 129 mM CaCO3) with twelve treatments; T1; Control, T2; NiNO3, T3; CaCO3, T4; NaCl, T5; BC, 130 T6; Ni+ BC, T7; CaCO3+ BC, T8; NaCl+ BC, T9; Ni+CaCO3+ BC, T10; Ni+NaCl+ BC, T11; 131 CaCO3+NaCl+ BC, T12; Ni+NaCl+CaCO3+ BC.
There are some unclear aspects regarding methods used in this study:
· Isotherm models (Langmuir and Freudlich isotherm)are presented as methods for study of Ni sorption. As authors presented, for this it was made a single extraction with DTPA+TEA+CaCl2. This is a standard method (ISO 14870) used for assessment of bioavaliabity of heavy metals in soils and is not appropriate to develop isotherm models. In order to construct an isotherm for biochar, a certain amount of biochar is added to a certain volume solutions (pH measured) containing different Ni2+ concentrations. The mixture is shaken at for a period of time to reach equilibrium. The Ni2+ concentration is determine in clear solutions. (please check the adopted methodology from the studies related to metal adsorbtion on soil or other materials).
· Line 215-217 – is not clear which method it was used to determine the chloride in soil: titrimetry (with silver nitrate) or potentiometry by ion-selective electrode.
Also, the authors have to revised the Results section because there a lot of mistakes regarding analysis and interpretation of the results. The authors incorrectly interpreted data from table 2. (line 280-281, 285-287).
The same situation is for Figure 2 and Figure 3. There are no relation between visual displays of data and the main text. It seems like authors discussed about another treatments.
Even in Conclusion section there are confused remarks related to treatments and values of indicators associated to them. (line 491 – 494).
Please revise the Sections Results, Discussion and Conclusions.
Author Response
Comment 1: Line 125-131: Each pot of twelve treatments was filled out with 4 kg of bhal soil. BC (1%) was applied to all pots (except control), homogenously by mixing it with soil and, after this for treatments description: The experimental set up was in triplicates having different materials BC (1%), Ni (0.5 mM NiNO3), Na (100 mM NaCl) and CO3 (100 129 mM CaCO3) with twelve treatments; T1; Control, T2; NiNO3, T3; CaCO3, T4; NaCl, T5; BC, 130 T6; Ni+ BC, T7; CaCO3+ BC, T8; NaCl+ BC, T9; Ni+CaCO3+ BC, T10; Ni+NaCl+ BC, T11; 131 CaCO3+NaCl+ BC, T12; Ni+NaCl+CaCO3+ BC.
Response: Thank you for the comment. Please see respective highlighted/ track change lines.
Comment 2: Isotherm models (Langmuir and Freudlich isotherm) are presented as methods for study of Ni sorption. As authors presented, for this it was made a single extraction with DTPA+TEA+CaCl2. This is a standard method (ISO 14870) used for assessment of bioavaliabity of heavy metals in soils and is not appropriate to develop isotherm models. In order to construct an isotherm for biochar, a certain amount of biochar is added to a certain volume solutions (pH measured) containing different Ni2+ concentrations. The mixture is shaken at for a period of time to reach equilibrium. The Ni2+ concentration is determine in clear solutions. (please check the adopted methodology from the studies related to metal adsorption on soil or other materials).
Response: Thank you for the valuable and very important comment. As per the reviewer suggestion, there should be different concentrations of Ni2+ with a certain amount of biochar required to construct the isotherms models; however, there are many different ways to predict isotherm models such as Dieguez-Alonso et al. (2018) applied the Langmuir and Freundlich isotherm models with single extraction to evaluate the PO3− and AsO3− adsorption behavior. They performed batch sorption experiments with a solid:liquid ratio of 1:200, at a temperature of 25 ± 2 ◦C and at an initial pH in the range 5.5 - 6. The contact time was 24 h in a shaker with a rotation speed of 115 min−1.
Dieguez-Alonso, A., Anca-Couce, André., Frišták, Vladimí., Moreno-Jiménez, E., Bacher, M., Bucheli, T., Cimò, G., Conte, P., Hagemann, N., Haller, A., Hilber, I., Husson, O., Kammann, C.I., Kienzl, N., Leifeld, J., Rosenau, T., Soja, G., Schmidt, H.-P., Designing biochar properties through the blending of biomass feedstock with metals: Impact on oxyanions adsorption behavior, Chemosphere (2018), doi: https://doi.org/10.1016/j.chemosphere.2018.09.091.
Simialrly, Dad F.P at al. (2020) have applied the Langmuir and Freundlich models on the different treatments combination of Cadmium rather than different concentrations. Please see the follwing reference:
Dad, F.P.; Khan, W.U.D.; Tanveer, M.; Ramzani, P.M.A.; Shaukat, R.; Muktadir, A. Influence of Iron-Enriched Biochar on Cd Sorption, Its Ionic Concentration and Redox Regulation of Radish under cadmium toxicity. Agriculture. 2020, 11, 1.
However, if the reviewer does not agree with our justification then we shall request them to send us for the second round of revision to remove this data from the results and discussion/ throughout the manuscript
Comment 3: Line 215-217 – is not clear which method it was used to determine the chloride in soil: titrimetry (with silver nitrate) or potentiometry by ion-selective electrode.
Response: The potentiometry method has been used for chlorides determination and mentioned in the respective line.
Comment 4: Also, the authors have to revised the Results section because there a lot of mistakes regarding analysis and interpretation of the results. The authors incorrectly interpreted data from table 2. (line 280-281, 285-287).
The same situation is for Figure 2 and Figure 3. There are no relation between visual displays of data and the main text. It seems like authors discussed about another treatments.
Response: Thank you for the valuable observation and pointing it out, we have addressed it thoroughly and figures and tables visuals have been properly placed in the results and discussion. Figures and tables with their visuals have been correlated in text.
Comment 5: Even in Conclusion section there are confused remarks related to treatments and values of indicators associated to them. (line 491 – 494). Please revise the Sections Results, Discussion and Conclusions.
Response: Thank you for the comment. The conclusion section has been revised carefully. In the results section, we have addressed all the issues as per your suggestions. Similarly, the discussion section has also been checked carefully.
Reviewer 4 Report
The study is well conducted and written. The following points may be taken care of
Line no 101-102: There is no relationship of rice husk to air pollution. Delete the line
The authors have published similar papers with different crop. Discuss about economics of the Enriched BC production in brief to give some novelty to the work
The study is well conducted and written. The following points may be taken care of
Line no 101-102: There is no relationship of rice husk to air pollution. Delete the line
The authors have published similar papers with different crop. Discuss about economics of the Enriched BC production in brief to give some novelty to the work
Author Response
The study is well conducted and written. The following points may be taken care of
Comment 1: Line no 101-102: There is no relationship between rice husk to air pollution. Delete the line
Response: Thank you for the positive comments and support. The mentioned line has been deleted.
Comment 2: The authors have published similar papers with different crop. Discuss about economics of the Enriched BC production in brief to give some novelty to the work
Response: The comment has been addressed and a separate heading 4.6 has been added to the discussion.
Round 2
Reviewer 3 Report
The manuscript was revised and the authors took into account the previous remarks.
