Toxic Metals in a Paddy Field System: A Review
Round 1
Reviewer 1 Report
The paper is well organized. It covers certain metals of concern in rice cultures. However, I was surprised that key elements are missing in such review, therefore looking as incomplete review. Arsenic in the world (rice producer countries like USA, Thailand, Italy, India) represents concerns and risks.
Among elements of growing concern, rare earth elements in soil are frequently discussed as a risk for agricultural food. Lanthanum is discussed in the paper but should tell us about the other lanthanides group.
The type of soil is key for assessing the metal bioavailability and bioaccessibility. The same kind of comment for sediment as a secondary pollution source of toxic metals. I can agree that physico-chemical factors were discussion in the soil amendment/treatment section, but the fate and behavior of toxic metals in soil should be better discussed in term of metal transfer to rice.
Author Response
The paper is well organized. It covers certain metals of concern in rice cultures. However, I was surprised that key elements are missing in such review, therefore looking as incomplete review. Arsenic in the world (rice producer countries like USA, Thailand, Italy, India) represents concerns and risks.
Answer: Thank reviewer for this valuable comment. We are sorry for the misunderstanding caused by our mistakes. The information is contained in supplementary material (tables S1 and S2).
Among elements of growing concern, rare earth elements in soil are frequently discussed as a risk for agricultural food. Lanthanum is discussed in the paper but should tell us about the other lanthanides group.
Answer: Thank reviewer for this valuable comment. We are sorry for the misunderstanding caused by our mistakes. The information is contained in supplementary material (tables S1 and S2).
The type of soil is key for assessing the metal bioavailability and bioaccessibility. The same kind of comment for sediment as a secondary pollution source of toxic metals. I can agree that physico-chemical factors were discussion in the soil amendment/treatment section, but the fate and behavior of toxic metals in soil should be better discussed in term of metal transfer to rice.
Answer: Thank reviewer for this valuable comment. The core idea of this paper is to pay attention to the impact of toxic metals on rice and the technical methods to alleviate the negative impact of toxic metals on rice at this stage. The fate and behavior of toxic metals will be our next researches. If “Toxics” is interested in these researches, we will consider submitting them after finishing.
Reviewer 2 Report
The authors majorly introduced toxic metals contamination and remediation in the paddy field system. Several suggestions about the manuscript are proposed below:
- I didn’t see any tables or figure, while they were mentioned in the manuscript.
- Detailing the method used to select papers included/excluded from the review.
- Overall, lack of synthesis and derived information from the information available at hand.
- Recent Trend and Challenges should be focused provided.
- The general structure needs improvement. Subsections would be necessary for specific focus. For some sections, the information was only generally listed and stacked. The logic was unclear. For example, for Section 2, the first paragraph is a general intro, and it would be much better if several subsections were followed. Also, the second paragraph needs to be classified based on current literature, instead of simply listing and squeezing information on so many HMs.
- Line 165, before going to the current most popular methods, please offer some general method classifications.
- Section 6 definitely needs subsections to clarify the logic structure. These might be based on different remediation mechanisms/techniques.
- For the rice-fish system, the authors mentioned flooded condition reduced HMs bioaccumulation, but the fish activity boosted oxygen transfer (intermittent irrigation). More elaboration/discussion is needed here.
- Line 55, delete “In 2020”.
- Language for title and first sentence in Section 3 needs revision.
Author Response
I didn’t see any tables or figure, while they were mentioned in the manuscript.
Answer: We are sorry for the misunderstanding caused by our mistakes. We corrected all of them. The information is contained in this manuscript.
Detailing the method used to select papers included/excluded from the review.
Answer: We are sorry for the misunderstanding caused by our mistakes. The core idea of this paper is to pay attention to the impact of toxic metals on rice and the technical methods to alleviate the negative impact of toxic metals on rice at this stage. The screening criteria of this paper are as follows: 1) Study the negative effects of toxic metals on rice; 2) Study the measures and methods of repairing or removing toxic metals in paddy fields; 3) for the same type of researches, the researches with wide concentration range and later publication time will be selected.
Overall, lack of synthesis and derived information from the information available at hand.
Answer: We are sorry for the misunderstanding caused by our mistakes. We corrected all of them. The information is contained in Recent Trend and Challenges, and Conclusion of this manuscript.
Recent Trend and Challenges should be focused provided.
Answer: Thank reviewer for this valuable comment. We added it.
The general structure needs improvement. Subsections would be necessary for specific focus. For some sections, the information was only generally listed and stacked. The logic was unclear. For example, for Section 2, the first paragraph is a general intro, and it would be much better if several subsections were followed. Also, the second paragraph needs to be classified based on current literature, instead of simply listing and squeezing information on so many HMs.
Answer: Thank reviewer for this valuable comment. We corrected all of them.
Line 165, before going to the current most popular methods, please offer some general method classifications.
Answer: Thank reviewer for this valuable comment. We corrected all of them.
Section 6 definitely needs subsections to clarify the logic structure. These might be based on different remediation mechanisms/techniques.
Answer: Thank reviewer for this valuable comment. We corrected all of them.
For the rice-fish system, the authors mentioned flooded condition reduced HMs bioaccumulation, but the fish activity boosted oxygen transfer (intermittent irrigation). More elaboration/discussion is needed here.
Answer: Thank reviewer for this valuable comment. According to the comments of the reviewers and the logic of the overall content, this part has been deleted.
Line 55, delete “In 2020”.
Answer: Thank reviewer for this valuable comment. We corrected it.
Language for title and first sentence in Section 3 needs revision.
Answer: Thank reviewer for this valuable comment. This part has been revised and adjusted (in Conclusion) according to the comments of the reviewers and the logic of the overall content.
Reviewer 3 Report
The article by Duan is timely and relevant to the field toxics.
I believe this review should include a small section on instrumentation. Please include a small paragraph on the types of instruments that are used to measure these TM’s.
The introduction can be improved, and I would highly suggest adding the following article to section 4 of the introduction. The location of this study was in Louisiana, USA. A large portion of Louisiana’s agriculture depends on rice production.
Bussan, D., Harris, A., & Douvris, C. (2019). Monitoring of selected trace elements in sediments of heavily industrialized areas in Calcasieu Parish, Louisiana, United States by inductively coupled plasma-optical emission spectroscopy (ICP-OES). Microchemical Journal, 144, 51-55.
I would be willing to accept this article with minor edits if the authors consider these suggestions.
Author Response
I believe this review should include a small section on instrumentation. Please include a small paragraph on the types of instruments that are used to measure these TM’s.
Answer: Thank reviewer for this valuable comment. We added it (in TM measuring instruments).
The introduction can be improved, and I would highly suggest adding the following article to section 4 of the introduction. The location of this study was in Louisiana, USA. A large portion of Louisiana’s agriculture depends on rice production.
Bussan, D., Harris, A., & Douvris, C. (2019). Monitoring of selected trace elements in sediments of heavily industrialized areas in Calcasieu Parish, Louisiana, United States by inductively coupled plasma-optical emission spectroscopy (ICP-OES). Microchemical Journal, 144, 51-55.
Answer: Thank reviewer for this valuable comment. We added it (in TMs sources in paddy fields).
Reviewer 4 Report
The manuscript is well-conducted. However, there are some aspects that should be improved.
1) Introduction: what is about the characteristics and toxicity of the metals? Please, include information about the toxic metals.
2) Material&Methods sections is not indicated. What is about the search items. How the authors select the articles cited in the manuscript?
3) Risk to human health section is not adequate.
4) Tables, figures... the manuscript is not complete. Tables of toxic metals concentration...
5) Conclusions: what is about the future perspectives?
Author Response
1) Introduction: what is about the characteristics and toxicity of the metals? Please, include information about the toxic metals.
Answer: Thank reviewer for this valuable comment. We are sorry for the misunderstanding caused by our mistakes. For “characteristics”, which already exists in the Introduction (Metals are typically classified ......in the later description.); For “toxicity”, which has been added into supplementary material (tables S1 and S2).
2) Material&Methods sections is not indicated. What is about the search items. How the authors select the articles cited in the manuscript?
Answer: We are sorry for the misunderstanding caused by our mistakes. The core idea of this paper is to pay attention to the impact of toxic metals on rice and the technical methods to alleviate the negative impact of toxic metals on rice at this stage. The screening criteria of this paper are as follows: 1) Study the negative effects of toxic metals on rice; 2) Study the measures and methods of repairing or removing toxic metals in paddy fields; 3) for the same type of researches, the researches with wide concentration range and later publication time will be selected.
3) Risk to human health section is not adequate.
Answer: Thank reviewer for this valuable comment. This part has been revised and adjusted (in Conclusion) according to the comments of the reviewers and the logic of the overall content.
4) Tables, figures... the manuscript is not complete. Tables of toxic metals concentration...
Answer: We are sorry for the misunderstanding caused by our mistakes. We corrected all of them. The information is contained in this manuscript.
5) Conclusions: what is about the future perspectives?
Answer: We are sorry for the misunderstanding caused by our mistakes. We corrected all of them. The information is contained in Recent Trend and Challenges and Conclusion of this manuscript.
Round 2
Reviewer 1 Report
The manuscript is now available for acceptance.
Reviewer 2 Report
The quality of manuscript by Duan et al. has been improved significantly. One more comment is to improve the quality of Fig. 1 by slightly enlarging the font and by using colorful images.
Reviewer 4 Report
The authors have improved the manuscript introducing the modifications.
