Geochemistry of Metals and Organic Matter in Water and Sediments of the Karst River Cetina, Croatia

Round 1

Reviewer 1 Report

The authors studied the geochemistry of metals and organic matter in water and sediments of a specific river in Croatia, the data was abundant and the discussion was appropriate, I suggest a minor revision before publication.

Abstract, what was the PCA, PC1, and PC2? The full names for these abbreviations should be given.

Line 30, superscript should be noted.

The innovation point of this paper should be clearly stated in the last paragraph.

Some outlooks could be proposed for the future management for the river.

The quality for these figures should be improved, the resolution could be enhanced.

Author Response

we took into account all reviewers´ comments and to re-submit our manuscript entitled: " Geochemistry of metals and organic matter in water and sediments of the karst river Cetina, Croatia" by Krešimir Maldini, Neven Cukrov, Kristina Pikelj, Natalija Matić and Marina Mlakar* for publication in Water, based on your final decision and recommendation.

We studied very carefully the comments and recommendations of three reviewers and acted accordingly, addressing point-by-point all the issues raised. We are grateful to the reviewers for their critical comments and thoughtful suggestions. Based on these comments and suggestions, we have modified the original manuscript. Additionally, please find below our detailed point-by-point response to the reviewers' comments. To the best knowledge, this is the first study on Geochemistry of metals and organic matter in water and sediments of the karst river Cetina, Croatia. Therefore, our results should be important study for further investigations.

Following this letter are our point-to-point response to reviewers’ comments including how and where our manuscript has been modified and a marked-up manuscript version showing the changes.

We also appreciate the journal’s reviewers for taking their precious time to review the manuscript.

We hope that you will find the revised manuscript improved and suitable for publication in WATER.

Author Response File: Author Response.docx

Reviewer 2 Report

ABSTRACT

No information given about the water samples. Almost all results are about the sediment samples.

How many samples did you analyzed?

Line 5: I couldn’t understand the statement “Due to … Mg and Si”. Please rewrite.

Line 7: What do you mean by PCA? Please give its full name.

Line 9: Please give full names of TN and TP.

Line 9: (TN, TP) → (TN and TP).

Line 12: Please give full name of TOC.

INTRODUCTION

Line 28: Transboundary river. I like it. Would you please add more information about the river and the political boarders? Also, please speculate about the importance of transboundary rivers and their related challenges, as well as support your statements by referring to the published papers such as “Hydropolitical System Archetypes: Feedback Structures, Physical Environments, Unintended Behaviors, and a Diagnostic Checklist”.

Lines 40-45: A long statement! Would you please break down it to more statements?

The authors should highlight the main purposes of their study at the end of Introduction.

STUDY AREA OVERVIEW

Line 88: How did you conclude that your sampling points are representative and they can monitor long-term changes in your study area? Please add more discussion or at least add a reference to support your conclusion.

METHODS FOR WATER ANALYSES

Line 119: Only EC and pH? Dis you measured DO in laboratory? Or in site?

Line 121: How did you calculate TDS and HCO3? Please describe or add a reference.

I would like to see more statement about QA/QC.

METHODS FOR SEDIMENT ANALYSES

This section has been poorly supported by authors. Please support this section with the published papers such as “Metal contamination assessment in water column and surface sediments of a warm monomictic man-made lake: Sabalan Dam Reservoir, Iran”.

I would like to see more statement about QA/QC.

WATER ANALYSES

Lines 171-174: Please move this section to Methods.

Table 1: Please add the appropriate references for Varimax rotation.

WATER ANALYSES

Figure 6: I see a general decreasing trend for DO in the depth of lake. It may be due to both thermal stratification and organic matters (specially TN and TP) in the lake (see “Hyper-nutrient enrichment status in the Sabalan Lake, Iran” and “Six decades of thermal change in a pristine lake situated north of the Arctic Circle”). Please discuss and support your discussion with the give references.

DISCUSSION

I would strongly suggest the authors to add more discussion about the presented results. The authors have presented the results well. But, they are failed to properly support the presented results with appropriate discussion. Comparison of he presented results with the relevant published papers (see “Iran’s groundwater hydrochemistry”, “Alarming carcinogenic and non-carcinogenic risk of heavy metals in Sabalan dam reservoir, Northwest of Iran” and “Metal pollution assessment in surface sediments of Namak Lake, Iran”) may help the authors to enrich discussion and increase the readability of the manuscript.

Good luck!

Author Response

we took into account all reviewers´ comments and to re-submit our manuscript entitled: " Geochemistry of metals and organic matter in water and sediments of the karst river Cetina, Croatia" by Krešimir Maldini, Neven Cukrov, Kristina Pikelj, Natalija Matić and Marina Mlakar* for publication in Water, based on your final decision and recommendation.

We studied very carefully the comments and recommendations of three reviewers and acted accordingly, addressing point-by-point all the issues raised. We are grateful to the reviewers for their critical comments and thoughtful suggestions. Based on these comments and suggestions, we have modified the original manuscript. Additionally, please find below our detailed point-by-point response to the reviewers' comments. To the best knowledge, this is the first study on Geochemistry of metals and organic matter in water and sediments of the karst river Cetina, Croatia. Therefore, our results should be important study for further investigations.

Following this letter are our point-to-point response to reviewers’ comments including how and where our manuscript has been modified and a marked-up manuscript version showing the changes.

We also appreciate the journal’s reviewers for taking their precious time to review the manuscript.

We hope that you will find the revised manuscript improved and suitable for publication in WATER.

Author Response File: Author Response.docx

Reviewer 3 Report

The reviewed manuscript is dealing with the Geochemistry of metals and organic matter in water and sediments of the karst river Cetina, Croatia. Major and trace elements were determined in sediments and water samples. Sediments and water samples were analyzed for major and trace elements. The topic is interesting and relevant to the journal's scope. In terms of methodology, the study was carried out thoroughly. Please consider the following recommendations to improve this manuscript.

1. Line 11; while the fourth group partially anthropogenic → was partially anthropogenic.

2. Line 11; hierarhical →hierarchical.

3. Line 12; four cluster → four clusters.

4. The Introduction; I recommend that you rewrite the introduction section in a much broader context, taking into account points such as the importance of studying sediment and water contamination, the various approaches used in addressing this problem, and the most relevant previous works addressed sediment and water contamination due to anthropogenic activity. Furthermore, The last paragraph of the introduction should clearly explain the objective of the study.

5. Please consider using some of these examples in the introduction and discussion.

https://doi.org/10.3390/w15030390

https://doi.org/10.3390/toxics11010042

https://doi.org/10.3390/su15032439

https://doi.org/10.3390/app13020771

https://doi.org/10.3390/ijerph192114293

https://doi.org/10.3390/su14063619

https://doi.org/10.3390/w14030441

https://doi.org/10.3390/ijerph19010234

https://doi.org/10.3390/w10121829

https://doi.org/10.3390/w14010124

https://doi.org/10.3389/feart.2021.712865

6. Line 18; belongs to → belongs.

7. Lines 40:45; Please explain a little bit about how the lithology contributes to the mentioned Goals (SDG 2, 3, 6, 7, 12, 13, and 15).

8. 2. Study area overview; I recommend moving this section under the Materials and Methods section and dividing it into two subsections (Study Area and Sampling). Please take into consideration merging the presented information in the introduction about the study area with this subsection.

9. Figure 1; This figure should be improved, considering adding coordinates (Long. and Lat.) and a clear scale.

10. I recommend moving all information about the Piper diagram (Lines 125:126), Factor analyses (Lines 137:138 and 156:157), and Normalisation of geochemical data (Lines 158:1680) to a new subsection Data Treatment.

11. Lines 171 and 178; dominant ions → major ions.

12. Line 221; accordance with [37] → accordance with Hair et al. [37].

13. Figure 5; Please improve the quality of this figure. In addition, you should define a, b, c, and d in the figure caption.

14. Figures 6-11; Please improve the quality of these figures.

15. Supplementary materials; It would be easier for the readers if the authors present the Supplementary materials in a one-word file. Please be sure to mention the presented supporting information in the main text as Table S1, Table S2, ……, Figure S1.

Author Response

we took into account all reviewers´ comments and to re-submit our manuscript entitled: " Geochemistry of metals and organic matter in water and sediments of the karst river Cetina, Croatia" by Krešimir Maldini, Neven Cukrov, Kristina Pikelj, Natalija Matić and Marina Mlakar* for publication in Water, based on your final decision and recommendation.

We studied very carefully the comments and recommendations of three reviewers and acted accordingly, addressing point-by-point all the issues raised. We are grateful to the reviewers for their critical comments and thoughtful suggestions. Based on these comments and suggestions, we have modified the original manuscript. Additionally, please find below our detailed point-by-point response to the reviewers' comments. To the best knowledge, this is the first study on Geochemistry of metals and organic matter in water and sediments of the karst river Cetina, Croatia. Therefore, our results should be important study for further investigations.

Following this letter are our point-to-point response to reviewers’ comments including how and where our manuscript has been modified and a marked-up manuscript version showing the changes.

We also appreciate the journal’s reviewers for taking their precious time to review the manuscript.

We hope that you will find the revised manuscript improved and suitable for publication in WATER.

Author Response File: Author Response.docx

Reviewer 4 Report

Abstract should better present novelty and contribution of this study.

Physical and theoretical interpretation of the results has been presented weakly.   The tables and results need more discussion and explanation.

The objectives of this study should be mentioned at the end of introduction. In fact, the journal reader asks what is problematic for this research? and how can the authors reply to the research questions?

The literature review is not critical and pertinent. It only reports some existing studies without clarifying their weak points for readers. The authors should present more profound investigation around the main subject of the research.

What are the key assumptions and limitations in this study? How can the authors manage the limitation?

There is no information regarding the reliability of data which authors used for this study.

This is a case study, so, how can one extend the methodology and results for other regions?

Abstract and conclusions need to be rewritten by revealing the novelty and contribution of this study.

Author Response

we took into account all reviewers´ comments and to re-submit our manuscript entitled: " Geochemistry of metals and organic matter in water and sediments of the karst river Cetina, Croatia" by Krešimir Maldini, Neven Cukrov, Kristina Pikelj, Natalija Matić and Marina Mlakar* for publication in Water, based on your final decision and recommendation.

We studied very carefully the comments and recommendations of three reviewers and acted accordingly, addressing point-by-point all the issues raised. We are grateful to the reviewers for their critical comments and thoughtful suggestions. Based on these comments and suggestions, we have modified the original manuscript. Additionally, please find below our detailed point-by-point response to the reviewers' comments. To the best knowledge, this is the first study on Geochemistry of metals and organic matter in water and sediments of the karst river Cetina, Croatia. Therefore, our results should be important study for further investigations.

Following this letter are our point-to-point response to reviewers’ comments including how and where our manuscript has been modified and a marked-up manuscript version showing the changes.

We also appreciate the journal’s reviewers for taking their precious time to review the manuscript.

We hope that you will find the revised manuscript improved and suitable for publication in WATER.

Round 2

Reviewer 2 Report

Dear Authors;

Thank you for addressing my comments. My suggestion is acceptance. Congratulations to the Authors.

 

Author Response

We uploaded the revised supplement below, as no other option.

Author Response File: Author Response.docx

Reviewer 4 Report

The authors revised the original version considerably. Now I recommend acceptance for this manuscript.

 

Author Response

we took into account all reviewers´ comments and to re-submit our manuscript entitled: " Geochemistry of metals and organic matter in water and sediments of the karst river Cetina, Croatia" by Krešimir Maldini, Neven Cukrov, Kristina Pikelj, Natalija Matić and Marina Mlakar* for publication in Water, based on your final decision and recommendation.

We studied very carefully the comments and recommendations of three reviewers and acted accordingly, addressing point-by-point all the issues raised. We are grateful to the reviewers for their critical comments and thoughtful suggestions. Based on these comments and suggestions, we have modified the original manuscript. Additionally, please find below our detailed point-by-point response to the reviewers' comments. To the best knowledge, this is the first study on Geochemistry of metals and organic matter in water and sediments of the karst river Cetina, Croatia. Therefore, our results should be important study for further investigations.

Following this letter are our point-to-point response to reviewers’ comments including how and where our manuscript has been modified and a marked-up manuscript version showing the changes.

We also appreciate the journal’s reviewers for taking their precious time to review the manuscript.

We hope that you will find the revised manuscript improved and suitable for publication in WATER.

Author Response File: Author Response.pdf