Autonomous In Situ Measurements of Noncontaminant Water Quality Indicators and Sample Collection with a UAV
Round 1
Reviewer 1 Report
Presented manuscript concerns autonomous in situ measurements of no contaminant water quality indicators and sample collection with a UAV. The Author should mention in conclusions, if obtained results will constitute a practical and quick tool for practitioners. This article is poor prepared. Article should be carefully edited according to Author’s guidelines. Abstract should be more concise. The introduction and the conclusion should include the value added with respect to existing research. The hypothesis or purpose of the work should be rewritten in more clearly way. Also the introduction should include information about problem, which should be investigated and background that explains the problem, as well as reasons for conducting the research. The current version of presented manuscript is not a scientific communication. The manuscript does not include the value added with respect to existing methods.
Author Response
We appreciate the feedback to improve our manuscript!
Please see the attached document for our responses to the Reviewers' comments. Page 1 contains the responses to the comments of Reviewer 1.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
This paper is the 3 part in one trilogy that have high potential. Some parts are confused like
the noncontaminant variable
The difficult, to sampling in each deep in the common in situ studies
i think that this papers is a very important develop, but need be weighted. This can be using the 2 paper Koparan et al (2018a and 2018b) …in a single way…by example see my comments in the line 106-113.
Also, the discussion part is need …in this section could include topics like comment 4, 5, 7 , 8, 9, 12, 13, 14, 15, 16,17, 19, 20
The citation needs a strong change format (comment 1, 2 , 10)
Particular comments are
1. Lines 26 and 27 the values are only in one station or is a average.
o In the abstract you made some relationship between UASS observation and in situ traditional data?
o In the manuscript…fallow the instruction to the authors (https://www.mdpi.com/journal/water/instructions#preparation) the references …References: “References must be numbered in order of appearance in the text (including table captions and figure legends) and listed individually at the end of the manuscript. We recommend preparing the references with a bibliography software package, such as EndNote, Reference Manager or Zotero to avoid typing mistakes and duplicated references. We encourage citations to data, computer code and other citable research material. If available online, you may use reference style 9. below.
o Citations and References in Supplementary files are permitted provided that they also appear in the main text and in the reference list.
o In the text, reference numbers should be placed in square brackets [ ], and placed before the punctuation; for example [1], [1–3] or [1,3]. For embedded citations in the text with pagination, use both parentheses and brackets to indicate the reference number and page numbers; for example [5] (p. 10). or [6] (pp. 101–105).
o The reference list should include the full title, as recommended by the ACS style guide. Style files for Endnote and Zotero are available.”
2. In the same way the cite in line 41 :
o Shoda, Sprague, Murphy, & Riskin, 2019
o Could be in standard science manuscript Shoda et al., 2019…in this paper could be [23] (or the number that correspond in references
3. Line 48 Schaeffer et al., 2013…and line 52 (Stauber, Miller, Cantrell, & Kroell, 2014) and line 58 Kim, Seo, & Choi, 2017; Yang et al., 2018. please made homogeneous your citation format…please check in figures tables equations and other structures in the manuscript.
4. Line 52 Dissolved oxygen (DO), electrical conductivity (EC), pH, and temperature are the noncontaminant water quality indicators that are measured and evaluated in situ (Chung & Yoo, 2015).
o But in the line 49 mention other regular monitoring sampling variables like clay, phytoplankton, organic matter…my point is these other variables need lab processes but are noncontaminant water quality indicators too…may be these variables have a natural fluctuation and in some specific case the anthropogenic activity can increase o decrease. The DO pH and may be the temperature could be considerate link to the anthropogenic activity…
o Maybe you need be clearer and rewrite these lines
5. Line 59 precise depth is a challenging task using existing methods
o You can mention with cite some of these approaches with cites and made some “pros and contras? this is a very important part in you paper because you are proposing an approach to substitute the classic sampling in situ.
6. Same observation line 64….i not understand your lines Water sampling depth and location cannot be adjusted with the fixed sensor stations because they are placed at certain depths...In oceanography is very common a sampling with a ctd with another sensors like DO, pH, Fluorimeter etc…need be clear in this sentence
7. Line 69-70 define Water sampling from lowered water reservoirs what deep have these reservoirs? And what are the complications to use a Kayak?
8. Line 73-76… do you mean use the sensor in temperatures high to apply the algorithm to transform the raw data to temperature? . maybe you need be, clearer in all these ideas…because you mention in the line 76 about the fouling… in this point you mix between in situ monitoring sampling (cover a grid of stations) and mooring data (like a buoy time series) please check each condition and be clear in you sentence.
9. Line 107 need definition about noncontaminant water quality indicators…the word noncontaminant has a big significance in laboratory analysis (that include a green approached) or is associated with the anthropogenic effects.
10. In the line 106 – 113 is not clear what are the different between Koparan et al (2018a and 2018b) papers…I read these papers and I think that you have the perfect trilogy…by this maybe you can make a full history support in:
o UAV electrodes vs Sonda (2018b…(please note that this paper is old by this you need rename in citation…to 2018a))…
o UAV electrodes with a “only sample bottle” (manual methods) (2018a that need rename to 2018b)
o UAV electrodes with 3 samples bottles=3 deep.
o My suggestion is made easier to read this saga…Like a separated note Koparan 2018a and 2018b were easier to read…focus in a fast evaluation of you word. This actual paper I have some details that not made the read easy.
11. Apparently in the manuscripts the citation are ok but not in references. Please check and fix
12. Line 120 and 121…are discussion not methods
13. Line 134…I don’t not to much abut the 3d print but I made some proof with pla and abs……v.gr. PLA is easy to print but is sensible to UV..ABS resist UV but maybe is not use to food contact because have with the time put some components that could be toxic…this characteristic made that you prototype need be replacement in short (degradation PLA parts)….by the new version maybe you can use another polymer like POM
14. Figure 2.. you say in the line 64 something about deep. I see the electrodes are 30 cm approx. up to the bottler samples…do you made some corrections about? May be 2 pressures sensors one in the electrodes and another one in the bottles can be uses in the next version.
15. Same figure …the bottler sample is not full horizontal…what could be you approach to fix the bottler position…?. Maybe install 4 lines one in each corner and made a common subjection point
16. I work with phytoplankton water color and optical proprieties …may suggestion is made a water sampler bottler with a not-transparent body …with these modifications you UAV could be use with another variables….in other situations like a red tide in costal water…
17. In your table 2 if you have n 48 observation why you DF are 2?..in a paired t test ..the df are the number of differences -1..these is mean that you only have 3 data with differences? I made a true interpretation? Can you write some about that?
18. I not see a discussion section and maybe all may comment could be integrated in this section.
19. In the same way what is the cost of these modification …I know that is a proof concept but may be made some estimation cost could be help.
20. What is the potential use? What need to fix and what is working ok…
Author Response
We appreciate the feedback and constructive comments to improve our manuscript!
Please see the attached document for our responses to the reviewers' comments. Pages 2-6 contain our responses to the comments of Reviewer 2.
Author Response File: Author Response.pdf
Reviewer 3 Report
Reviewer: General comments:
This study describes a suitable approach for water quality sampling and autonomous in situ measurements of noncontaminant water quality indicators with a UAV. Authors make a good effort to integrates their two previous studies (autonomous water sampling and In situ water quality measurement). Their finding is interesting and it is within the scope of the journal (WATER). I suggest you state and explain clearly why this system has an over advantage than existing automatic monitoring system which is more consistent and useful such as automatic wireless monitoring system network.
The applicative approach results interesting and within the scope of this Journal. The reading is reasonable and the work is well written. Nevertheless, I guess that some minor improvements could be useful to improve the manuscript; thus, I suggest to consider it as minor revisions. My serious concern is also about the feasibility of this approach over the existing approaches such automatic wireless monitoring system, which provides consisting information for a longer period of time at an hourly or daily basis. Overall this designed system seems to be only useful for a specific survey for a short period of time but does not provide a permanent water quality monitoring for sustainable water quality management.
In greater details, the Abstract could be shortened, making the contents more effective.
Keywords should be improved. I suggest to add UASS and rewrite in situ measurement and in situ sampling instead of “water sampling; in situ sampling”
Specific Comments
1. In the introduction section. The author should provide more information about the importance and feasibility of the designed methods.
2. "Introduction section". The manuscript could be more substantially improved by relying on and citing more literature about the importance of the designed study by comparing with existing methods such as conventional data collection, automatic wireless monitoring network, Autonomous Aerial Water Sampling, and Navigation System of an Unmanned Boat for Autonomous Analyses, etc.
3. Is the designed system being also useful for ground observation collection over a long profile of a river?
4. What is UAV flight range in km?
5. Please provide the date and time schedule of survey conduction.
6. Why authors choose the specific study area for water quality sampling.
7. Why system was designed only for specific depth i.e. 0.5m and 3 m. What is the rationale behind the selection of the specific depth?
8. In result and discussion section. The result shows some variation in the values (concentration) of nanocontainment water quality indicators over two different depth. Please provide scientific discussion about the variation of indicators values.
9. Please revise the conclusion more clearly.
I believe that after revision and if the author follows all reviewer suggestions, this paper is suitable for “water” Journal. I would like to check it again after revision before any final decision.
Comments for author File: Comments.pdf
Author Response
We appreciate the feedback to improve our manuscript.
Please see the attached document for our responses to the reviewers' comments. Pages 7-9 contain our responses to the comments of Reviewer 3.
Author Response File: Author Response.pdf
Round 2
Reviewer 1 Report
Almost all my numerous remarks were included, except the improving the quality of figures (charts).
Author Response
We appreciate for the comments to further improve our manuscript. We improved the quality of the Figures and Tables in the revised manuscript.
Specifically:
1- We changed the styles of Table 1 and Table 2, and increased the table sizes in the revised document.
2- We increased the size of Figure 5.
3- We increased the sizes of Figures 6 and 7, and rearranged the legends and scales on these graphs to make the graphs clearer.
4- Figure 8 is also updated with better scales and the legends are located on the top of each chart.
Reviewer 2 Report
This version 2 show a better structure...only in the discussion part i find only one reference. if you make a separated part between result and discussion the discussion show a very weak.
My only comment is you need reforce you discussion part
Author Response
We appreciate for the comments. We re-evaluated the discussion section and re-organized it. We reinforced the discussion section with additional literature to address the gap that was mentioned in the introduction section. The newly added section is highlighted with red font in the revised document.
