Review Reports
- Jorge Crespo1,2,*,
- Elizabeth Holley1 and
- Madeleine Guillen3
- et al.
Reviewer 1: Pedro M. Nogueira Reviewer 2: Peter Voice Reviewer 3: Dinesh Pandit Reviewer 4: Paulo Miguel De Bodas Terassi
Round 1
Reviewer 1 Report
The article is well-written, clear, and comprehensible. However, some suggestions for improvement in writing clarity and elaboration are proposed. The introduction and objectives are clearly defined, noting that the objectives point towards a regional case study and the application of a previously existing tool. It would be important to include a point that highlights the potential global implications of the results obtained. The results are well presented, but improvement suggestions have been made for the graphs and figures, as some are hard to read and others are redundant. The discussion could be more in-depth and refer to what other methodologies could bring to understanding the problem. The conclusions are very general, more specific conclusions for the case study and methodological conclusions could be drawn.
Comments for author File: 
Comments.pdf
Author Response
Please see the attachment
Author Response File: Author Response.pdf
Reviewer 2 Report
The paper is logically and well-organized. The text is readable – with only minor grammatical flaws. My main complaint for the paper is that several of the figures are unreadable and could be better drafted to reflect their work. Below are my comments tied to line numbers and figure numbers:
Paragraph starting on line 69 – has any work been done in the area to look at degradation of the fauna and flora. Are any of the more soluble metals bioaccumulating in animals living in these waters? Are there any epidemiological studies relating health of the local population to the release of metals (and Hg from the mining procedures) to this river system? It would be useful to provide some evidence of harmful degradation from this mining-related contamination.
Line 112 – I would write hydrological instead of hydrology.
Line 156 – use basement rock instead of rock basement.
Line 171 – note both watershed and scale are misspelled.
Figure 2 – through the manuscript you refer to Upper, Middle, and Lower sources – it may be worth adding some boundaries on this map and subsequent maps that show the approximate boundaries of these three source regions.
Line 204 – need a space between “47and”
Line 220 – delete “are”
Figure 3c – Why arrange the box plots as Upper, Lower, Middle for each element? It makes more sense to arrange the box plots – Upper, Middle, Lower like the inset legend does. Also, the model box plot – the labels could be typed in a slightly larger font. When printed, the number of analyses above detection limit labels are impossible to read (they are more readable in the pdf – but my adobe acrobat scales the pages to 200% - so they should be more readable).
Figure 4 – the axe labels and legend are impossible to read in the printed version of the manuscript. In the pdf, they are just barely readable – also the markers in the legend are too small to really differentiate in terms of shape.
Figures 5 and 6 – these plots are incredibly frustrating. Why do the observations plot outside the boundaries of the ternary diagrams? Why bother scaling the axes when they are unreadable? What are the three components being plotted – the labels appear to be 51, 53, and 57 but I have no idea what those refer to.
Line 343 I would recommend defining MPL as the acronym isn’t defined in the text.
Line 349 – I am not familiar with the term Quimbaletes – it might be worth defining it for your reader.
Author Response
Please see the attachment
Author Response File: Author Response.pdf
Reviewer 3 Report
Reviewer Blind Comments to Author:
This research paper (sustainability-2209184-peer-review-v2) is a case study of water-rock interactions due to anthropogenic activities caused by artisanal mining in the Ocona watershed of southern Peru. The case is special to the status of environmental problems arises due to human population growth and their interactions with dynamic ecosystem that increases additional challenges in the watersheds and river systems. The study suggested effective management practices to administrate natural resources that minimize the anthropic pollutants into the watersheds and catchment areas of river systems. Results of statistical analysis has been presented to explains the toxic pollutant originated from the sediment provenance and added to the water systems. Such processes should be minimized to improve the situation of natural ecosystem around the catchment areas of the river system. It is one of the significant contributions to understanding the mining activities causes erosion and sedimentation leading to the deterioration of natural environments. Present research contributes to develop more sustainable management practice is necessarily required to adopt for water bodies in the region with large anthropic pollution due to human activities. This study emphasises the sediment transport model to discriminate the different sediment provenance of anthropogenic constitutes causes environmental problems. This subject is most important to be addressed fundamental issues to the scientific community and must be published in Sustainability.
This article is properly written with respect to English grammar and appropriate organization of sentences are written in the manuscript.
I suggested this manuscript is suitable to recommend for publication in the Sustainability.
Author Response
Response: The authors deeply thank Reviewer 3 for the time and effort invested in our work.
Reviewer 4 Report
Dear Authors,
I highlighted below some points that was essential to made my decision to "major revisions" in this paper:
- The abstract is very extensive and exceeds the limit of words according to MDPI standards;
- The introductory text is wordy and does not present an ideas articulation. The central problem is not well presented throughout the introductory text;
- The novelty, economic impact and practical applicability of this study should be highlighted more;
- It is not appropriate to insert a distant figure the first time it is mentioned;
- A proper presentation of the study area is not performed. Even the location map does
- The presentation figure should also include Peru's location in South America, as it is a publication in a journal;
- There are two figures 2. The first of them on page 6 and the second on page 7. Separate into 2a and 2b for example;
- Methodological procedures and statistical analysis need to improve their description and organization;
- The description of methodological procedures is the most fragile point of the manuscript. Give more details of what was applied;
- The resolution of the figures is very low. More than half of Figure 3 was unavailable;
- The diagrams and other figures are well elaborated, but the presentation of these results in the text is also very insufficient;
- It is possible to identify the presentation of methodological procedures throughout the results. Describe methodological procedures only in the item "Material and Methods";
- The formatting of the manuscript is very inappropriate and careless according to the MDPI rules;
- Formatting errors and repeated figures disqualify the manuscript;
- The discussions are not well articulated with the literature and does not directly relate the results obtained to other research on what is investigated;
- Conclusions part can be improved in the paper. Here is presented in a general concept. Is the used methodology in the paper valid for all areas or is there any limitation or classification for the application?
- Above all, this research has interesting results, which are not well organized and systematized.
Kind regards.
Author Response
Reviewer 4 Round 1
We deeply appreciate the time and efforts invested by Reviewer 4. This is the third version of the manuscript, which has incorporated the comments of three more reviewers (in two rounds of revisions). The authors agree with the comments from Reviewer 4 and have made significant changes to the entire manuscript to meet both his/her comments and MDPI’s formatting rules. We hope this improved version is good enough for acceptance. Below please find a response to all your comments.
I highlighted below some points that was essential to made my decision to "major revisions" in this paper:
- The abstract is very extensive and exceeds the limit of words according to MDPI standards;
Response: We appreciate the comment and apologize for the error. We have reduced the Abstract to meet the MDPI’s word limits.
- The introductory text is wordy and does not present an ideas articulation. The central problem is not well presented throughout the introductory text;
Response: The authors appreciate the Reviewer 4’s comment and agree. We modified the text to improve it’s content and better articulate its topics. We hope that Reviewer 4 approves this new version.
- The novelty, economic impact and practical applicability of this study should be highlighted more;
Response: We have incorporated those topics in the Discussion.
- It is not appropriate to insert a distant figure the first time it is mentioned;
Response: Fixed.
- A proper presentation of the study area is not performed. Even the location map does.
Response: Reviewer did not finish sentence. However, new version includes the study area description.
- The presentation figure should also include Peru's location in South America, as it is a publication in a journal;
Response: Peru’s location is already included. However, the country’s name wasn’t there, so we included it.
- There are two figures 2. The first of them on page 6 and the second on page 7. Separate into 2a and 2b for example;
Response: Addressed in second version, after first round of reviews.
- Methodological procedures and statistical analysis need to improve their description and organization;
Response: We have improve this section accordingly.
- The description of methodological procedures is the most fragile point of the manuscript. Give more details of what was applied;
Response: Methodology section was improved accordingly.
- The resolution of the figures is very low. More than half of Figure 3 was unavailable;
Response: Figures were done using Adobe Illustrator, in a high resolution. As a consequence, unfortunately, we cannot improve the resolution more than what it is now. However, Figure 3 was splitted into two figures to increase resolution.
- The diagrams and other figures are well elaborated, but the presentation of these results in the text is also very insufficient;
Response: More comments were added in the text.
- It is possible to identify the presentation of methodological procedures throughout the results. Describe methodological procedures only in the item "Material and Methods";
Response: The authors agree. Text was modified accordingly.
- The formatting of the manuscript is very inappropriate and careless according to the MDPI rules; The authors agree and apologize.
Response: We have modified the manuscript accordingly.
- Formatting errors and repeated figures disqualify the manuscript;
Response: The entire manuscript was substantially improved. However, no figures were repeated, and we assume Reviewer 4 is seeing them more than once because he/she is using Microsoft Office 365 (online version) instead of Desk Office. We recommend using the latter version, for clarity and better resolution.
- The discussions are not well articulated with the literature and does not directly relate the results obtained to other research on what is investigated;
Response: The authors agree and have included a section on global perspective.
- Conclusions part can be improved in the paper. Here is presented in a general concept. Is the used methodology in the paper valid for all areas or is there any limitation or classification for the application?
Response: The authors agree and have improved the Conclusions substantially.
- Above all, this research has interesting results, which are not well organized and systematized.
Response: We have improved the entire document accordingly.
Round 2
Reviewer 2 Report
The authors have revised the manuscript and have addressed the majority of my concerns. I am still concerned with figures 5 and 6 - the authors have made the diagrams more readable, but I do not understand why their observations plot outside of the boundaries of the ternary diagrams. Ternary diagrams are three-component plots. I assume that the three source areas represent each side of the triangle (and this is not labeled on the ternary key diagram on the right) - all observations then represent some combination of material sourced from each source region - i.e., 40% from source 1, 35 % from source 2, 25% from source 3 for a specific element - if the three sources do not add to 100% - then they should be normalized to 100% - and the normalized observations would fall within the boundaries of the ternary diagram. Yet, these 2 figures show a number of ternary plots with fields of points that plot outside the boundaries of the plots.
Also, when you compare the figures 5 and 6 from the original draft to the most recent draft, all of the ternary diagrams appear to be mirror images of the original plots????
Author Response
Reviewer 2 Round 2
The authors have revised the manuscript and have addressed the majority of my concerns. I am still concerned with figures 5 and 6 - the authors have made the diagrams more readable, but I do not understand why their observations plot outside of the boundaries of the ternary diagrams. Ternary diagrams are three-component plots. I assume that the three source areas represent each side of the triangle (and this is not labeled on the ternary key diagram on the right) - all observations then represent some combination of material sourced from each source region - i.e., 40% from source 1, 35 % from source 2, 25% from source 3 for a specific element - if the three sources do not add to 100% - then they should be normalized to 100% - and the normalized observations would fall within the boundaries of the ternary diagram. Yet, these 2 figures show a number of ternary plots with fields of points that plot outside the boundaries of the plots.
Also, when you compare the figures 5 and 6 from the original draft to the most recent draft, all of the ternary diagrams appear to be mirror images of the original plots????
Response: Thank you for bringing up the issue with the triangle plotting. We apologize for the accidental change in the source ordering, which resulted in a different visualization of the triangles. The code has been modified to rectify this, and the triangle visualization is now correct.
Regarding the Reviewer 2’s concerns about the points outside the triangles, it is important to note that this is a normal and expected outcome when using the CI method. As this method is well-established, we believe that graphical representation is the best way to explain it. The CI and ternary diagrams display "all" the possible solutions that each individual tracer can introduce into the model. These predictions are based on the values of the sources and the mixture of the specific tracer, combined with virtually created tracer values to explore all possibilities. In the upper part of the figure below, represented by three tracers (T1, T2, T3), we can observe this phenomenon.
However, let's consider a scenario where we only want to know the prediction of each tracer when interacting with other tracers that are all conservative. In that case, all the points would fall inside the triangle, as you mentioned. In our example, this would occur if we only used T1 and T2 (the points surrounded by the green circles). However, when these tracers interact with T3, where the mixture is "non-conservative" and falls outside the range of sources, the predicted point falls outside the physical space represented by the triangle (the points surrounded by the red circles). Thus, if we solely use data from fully conservative tracers, rather than exploring the entire prediction range of each tracer, the points would remain inside the triangle.
For clarity to the reader, we have included a good reference in the figures’ caption, where ternary diagrams are explained in more detail.
Reviewer 4 Report
Dear Authors,
I checked that you made all suggestions and improve your manuscript. My decision is "accept in present form". Congratulations!
King regards.