A Forecasting Method for Harmful Algal Bloom(HAB)-Prone Regions Allowing Preemptive Countermeasures Based only on Acoustic Doppler Current Profiler Measurements in a Large River
Round 1
Reviewer 1 Report
It would bi appropriate in section "3. Study area" to give the hydrochemical and hydrobiological characteristics of the study area, with a link to the specified site (linc 281), and not just give a link to the site. Indicate the names of the main forms algae causing harmful water bloom, give their maximum and average number
Author Response
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Reviewer 2 Report
he paper treats a very important problem related to the broadly understood topic of water eutrophication as a result of anthropopressure. One of the symptoms of eutrophication is algal blooms, which contribute significantly to the deterioration of water quality. The authors proposed a method of forecasting areas where algae blooms may occur (often before the actual flowering period), which will allow for a quick response in taking preventive measures. At this point, it wonders what remedial measures the Authors think about, because they do not explain it in the text. Therefore, the method is of a monitoring nature. It involves the analysis of temperature data, the depth of the flow velocity and the thickness of the sediments based on the acoustic methodology. According to the authors, this method eliminates the need to perform physicochemical analyses of water, and thus the range of monitoring is much wider. The purpose of the study was formulated very briefly, it can be assumed that the authors, as the purpose of the study, exclude the need for physicochemical analyses of water (with particular emphasis on the assessment of phosphorus and nitrogen concentrations of nutrients) in favour of the proposed method in monitoring. I believe that the purpose of the work requires clarification. The method itself is difficult for me to assess, but the range of the predicted algal blooms is actually significant. The method seems to be effective, I think it needs further observation. Chapter “Conclusions” should rather be called “Summary”. We have the Authors' statement "We expect that this method can be used to mitigate environmental hazards" once again, and once again the question is how?
In conclusion, I find the work worth publishing due to the issues it raises, but I believe that it requires a few clarifications, mentioned earlier.
Author Response
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Reviewer 3 Report
A general observation is that this is an interesting study with regard to a method for forecasting HABs development based on acoustic Doppler current profilers (ADCPs) and subsequent machine-learning spatial clustering techniques in HAB-prone areas, such as rivers. Certain parts of the manuscript, however, need improvement in order to better present the information provided and to make more comprehensive and reader-friendly. In fact, the biggest problem of the manuscript is not from a scientific point of view, but that it suffers structure-wise, thus needing significant rearrangement of its content between different sections. There is also a general need for improvement of the use of English language. Detailed comments follow:
Abstract
- Page 1, line 28 (and title): Please explain ADCP at this first instance in the text and refrain from using unexplained abbreviations in the title.
- Introduction:
- Page 1, lines 38-41: HABs are not only located in lakes or rivers – they can also occur in marine waters and are not always green. The authors need to rephrase this part to be correct and provide relevant references. Are actually the authors thinking only about specific types of blooms (e.g. cyanobacterial ones?). If so, they should rephrase for clarity.
- Page 2, line 75: The term “in situ” should be in italics – please correct accordingly (multiple instances in the text).
- Page 3, lines 103-129: I believe that most of these details should be a part of the Materials and Methods section and not of the Introduction one. A brief presentation of the capabilities of ADCP data could be included in the Introduction section, along with reference to previous published works in this field, but describing the choice of methods should not be a part of this section, at least not in such detail.
- Materials and methods:
By definition this section should also contain the “materials”, e.g. sampling areas, equipment etc. In this context this section should be merged with section 3 (Study area) and subdivided in relevant subsections, such as: 2.1 Sampling area; 2.2 Conduction of measurements (equipment); 2.3 ADCP Backscatter; 2.4 Spatial autocorrelation analysis; 2.5 Hot spot analysis; 2.6 Statistical analysis (subsection completely missing, although some details are provided). This structure is only indicative, but gives an idea how the section should be organized to comply with a research manuscript structure. Other details:
- Page 3, lines 142-145: This type of details needs to be moved to the introduction section, as it refers to work of others related to ADCP.
- Page 4: Description on the conduction of measurements (equipment used, photos, sampling strategy) should precede this section, in order to ensure comprehensiveness.
- Page 4, lines 170-176: This type of details needs to be moved to the introduction section.
- Page 5, lines 202, 204, 205: z-score or z-value? Please keep only one term throughout the text.
- Study area:
As indicated in the previous section comments, this section should be merged into the Materials and methods section.
- Page 7, Figure 1: This figure should be moved towards the beginning of the M&M section to better describe the experimental design of the study.
- Page 8, lines 245-260: This type of details should not be a part of the Materials and Methods, most probably should be moved to the introduction section.
- Page 9, lines 271-289: These details are definitely not related to study area, so the section title does not cover conduction of measurements. Please re-structure as indicated above.
- Results:
- Page 15, lines 438-440: The authors should provide more details on the HABs reported annually, especially by conventional measurement methods, such as type, concentrations, duration etc. in order to better support their results.
- A large part of the results section is actually discussing or explaining the results and is probably more suitable for the discussion section. It is suggested that the authors merge the “Results” and “Discussion” sections into a combined “Results and Discussion” section to better present their results, and divide to individual subsections so that the structure is more coherent.
- Discussion
- The discussion section as presented, does not contain any comparisons with already published previous works to support the current study results. It is mostly discussing the main challenges and lessons posed by environmental restrictions, tools, and data during the conduction of the present study, which are, of course, useful, but should not be the only content of the discussion.
- The authors should elaborate more on the briefly mentioned “comparative results with actual algal blooms”, mentioned in page 18, lines 542-546, so that they better establish the practical applicability of their method and support their conclusions.
- Conclusions:
- Conclusions as presented, especially in the first paragraph, resemble more to an abstract, summarizing all the work done, rather than a conclusions section. The authors are suggested to limit this part to only the conclusions of the study without such an extensive reference to the work done and the study results.
Author Response
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Author Response File: Author Response.docx
