ASGM Mercury Discharges in Tropical Basins: Assessment of the Criticality of Their Geographical Distribution

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

This work presented a new Vulnerability Index to assess ASGM mercury discharges in tropical basins, and the authors concluded that a precise distribution of ASGM is crucial to effectively evaluate the fate of mercury and its resulting effect on the local ecosystems. After carefully reviewing this paper, I don’t think this present form can be acceptable for publication in Sustainability according to the following comments. 

1.        Title

There should be no full stop after the title. Delete the full stop.

2.        Abstract

(1)     Line 2, it is better to delete “as opposed to emissions into the atmosphere”, because the emissions of Hg into the atmosphere is beyond the research.

(2)     Lines 2-4, I suggest the sentence can be revised to “This is a key point to understand the potential exposure to mercury for ecosystems and population living in the river basins where ASGM is practiced. …”.  

(3)     Lines 5-7, remove “Differently from emissions into the atmosphere, for which the exact location of the release has a limited impact on the mercury fate, due to its very slow reaction”, and change it to “For such a potential risk, less is known regarding…”.

(4)     Lines 8-11, the sentence is too long, with too many verbs. It is not easy for readers to understand what the authors mean. Please put “a newly introduced Vulnerability Index” ahead because it is the novelty of this work. Also, please add some details about this “Vulnerability Index”. Otherwise, it is just an ambiguous conception.      

3.        Introduction

(1)    Line 18, please change “Infact” to “In fact”.

(2)    Line 38, change “Consequently, health risks by these processes are due to” to “Consequently, these processes might result in health risks due to”.

(3)    Line 40, change “In this last way,” to “For the latter,” or “For the latter case,”.

(4)    Line 42, delete “increasingly affected by health diseases”.

(5)    Line 52, change “existing emissions mappings” to “existing emission mappings”.

(6)    Lines 55-56, “For these reasons is crucial the definition of the spatial and quantitative contribution of the Hg discharges in the global cycle”, where is the object in this sentence? “For these reasons” or “the definition”? You can change it to “For these reasons, the definition of the spatial and quantitative contribution of the Hg discharges in the global cycle is crucial”.

(7)    Lines 60-61, revise this expression “where Hg captured by sediment, fixed in aquatic trophic chain and into terrestrial consumers” as “where Hg was captured by sediment, fixed in aquatic trophic chain and entered into terrestrial consumers”.

(8)    Line 62, “losses of biodiversity also” makes readers confused, change it to “biodiversity loss”.

(9)    Lines 75-76, change “and so far from urbanised areas where the people nutrition are varied exposing populations differently” to “, where people's nutrition varies with populations”.

(10) Line 77, in “The Authors”, I would like to ask you who are the authors? There are many expressions of “the Authors”, such as in Line 91, line 115, line 123, etc. It is not recommended to use “the Authors” in an academic paper. And you will find that “the authors” in Line 77 and Line 115 are not completely the same authors, except for the first two authors.

4.        Materials and Methods

(1)     Line 112, “kg/m2/s” should be “kg/m²/s”.

(2)     Line 136, change “the others ones” to “the other ones”.

(3)     Line 141, change “variable” to “variation”.

(4)     Line 168, delete “obtained from”.

(5)     Line 171, change “discharges value” to “discharge value”.

(6)     Line 190, “2.3. Vulnerability, for what?” is a strange subtitle, please change it to “2.3. Vulnerability factors”.

Also, the authors must give a clear definition of “vulnerability” in this work, or what is “vulnerability”.

(7)     Lines 193-194, change “through to organic matter and stay there for a long time” to “and stay for a long time through organic matter.”

(8)     Lines 207-209, please add references for this point “It has been already found that great part of water bodies in the world are highly polluted by toxic metals with a remarkable impact on the health of people.”

(9)     Line 209, change “Therefore, it is necessary a monitoring of …” to “Therefore, it is necessary to monitor …”.

(10)   Lines 220-223, the sentence is too long, please rewrite it.

(11)   Lines 229-230, “based on blood, urine and hair analyzes [49] of pregnant women, children and men, …”, only the pregnant women? How are the women without pregnancy?

(12)   Lines 239-241, there are two individual sentences, please split them or add a conjunction word.

(13)   Lines 241-243, how do the authors know the Hg is very high in rivers and neighboring sediments?

(14)   Line 258, “… values of estimated discharges”, where are the estimated discharge values from?

(15)   Line 271, change “Following a …” to “Following is a …”.

(16)   Line 272, “within each basins” should be “within each basin”. This error can be found in line 275.

(17)   Lines 280-281, define D_j and A_j separately.

(18)   Lines 289-291, where is the verb of this sentence?

(19)   Page 7, Figure 1, the authors should separate Figure caption and the details about explanation of this figure. Don’t use colon between them. And all the figure captions in this paper should be formatted.

5.        Results and Discussions

(1)     Lines 304-305, delete this paragraph.

(2)     Line 317, “… such as Mongolia and Brazil”, where can you find the evident gap in Mongolia”, please check your Figure 2.

(3)     Page 9, the resolution of Figure 2 is low. The authors should mark (a), (b) and (c) in this figure. Also give explanations to this figure.

(4)     Line 330, delete “according to”.

(5)     Line 344, what do you mean of “Figure ??”.

(6)     Line 346, change “9*10 -5 kg/cell” to “9×10^-5 kg/cell”.

(7)     Page 11, Figure 3, mark (a) and (b), and give explanation for the two panels.

(8)     Lines 372-374, please explain the differences among IVm A, IVm E, IVm D and IVm complete. How do you define IVm complete, including population density, area and amount of Hg discharge? Then what is the algorithm in IVm D?

(9)     Line 374, what do you mean “in Table 1 ?? and Table 2 ??”.

(10)   Lines 389-400, the unit should be “μg/g”, not “ug/g”.

(11)   Lines 349-400, why the values opposite to those of Authors model were instead found in China? Please give an explanation.

(12)   Pages 15 and 16, Table 1 and Table 2, the tables should be formatted. Caption should be given at the top not the bottom of the table. Also, mark lines in the table. Why the discharge values in Table 2 are zero. Please give explanation for it. The authors also need to tell where the values are from.

6.        Conclusion

(1)     Line 417, “… aspects not investigated until now”, what are the aspects considered in this study?

(2)     Lines 422-424, there are two individual sentences, “it was considered that…, it was necessary above all to pay attention to …”. Such grammar errors should be corrected and checked in the whole manuscript.

(3)     Line 429, change “By comparison…” to “By comparing…”.

(4)     Line 433, change “showed” to “shown”.

7.        Reference

(1)     Please check the form of all the references in Reference section and follow the reference guidelines of this journal.

(2)     Line 526, ref 32, please give website information if there is. Also check refs which are not from journals or book, please add website information so the refs can be searched.

8.       The author should submit a detailed description of the proposed Matlab algorithm for IVm A, IVm E, IVm D and IVm complete in the supporting information. It is better to give information how many files (including geo-referenced files, digital elevation, population density and emissions from AMAP and EDGAR) were utilized in this study.

Comments on the Quality of English Language

The authors should scrutinize for the whole manuscript and correct the grammar errors. Some are given in the comments. Please remember that don't use long sentences or combine several individual sentences together. 

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

The study report useful data in the field of environment and health protection, with the focus on Hg. Nevertheless, the authors must carefully edit the manuscript, mostly avoiding the use of the word authors, but stating sentences in the third person or describing the process, etc. Technical issues like Figure?? (line 344) or Table1 Table2?? (line 374) must be corrected. In line 49-50 abbreviation should be written after first giving the full name. Also, some data about the quality control of the work should be given. Thus, I recommend the publication of the work after corrections.

Comments on the Quality of English Language

Minor editing of English language required.

Author Response

Please see the attachment

Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

ASGM mercury discharges in tropical basins: assessment of the criticality of their geographical distribution

 

Manuscript No: sustainability-2878878

 

Interesting manuscript which can be accepted after minor revision.

Some comments:

 

1.What is purpose of proposed methodology without quantitative indicators (quantification of Hg distribution, ecotoxicological, toxicological etc.)?

2.It is not clear what authors present on Figure 3, caption?

3. Line 344 – Figure ??

4. Line 374 – Table 1?? and Table 2??

Comments on the Quality of English Language

moderate editing

Author Response

Please see the attachment

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

The authors revised their manuscript carefully. Now it can be accepted for publication. But I do have one suggestion for the authors: please arrange your paper well, it is not readable when there are lots of white pages. Please don't argue that it is because of the usage of Latex.   

Comments on the Quality of English Language

The language of this paper is still required to be polished. 

Author Response

Dear Reviewer,

thank you for your feedback.

We edited titles and captions of tables as indicated and we deleted the white pages.

Best regards.

Reviewer 2 Report

Comments and Suggestions for Authors

Authors have improved the manuscript, thus I recommend to publish the paper, but some technical corrections are needed, for example the title of the table must be written above the table.

Comments on the Quality of English Language

Minor editing of English language required.

Author Response

Dear Reviewer,

many thanks for you feedback.

We addressed all the formatting comments. We edited titles and captions of tables as suggested.

Best regards.