Interaction of Irregular Distribution of Submerged Rigid Vegetation and Flow within a Straight Pool
Round 1
Reviewer 1 Report
This paper analyzes the flow characteristics, e.g., flow velocity and flow turbulence, in a flume characterized by a pool topography, with and without vegetation. The authors have done extensive experimental work and performed detailed data analysis. However, because of several critical concerns, I recommend not to consider this manuscript at this time. There are three major concerns:
- The reliability of the experimental data. This is my biggest concern for this paper. Because a lot of research work has been done on similar issues and topics, i.e., conducting turbulence measurements (ADV) for the vegetated channels with different topography (the pool in this study), The results in this paper are not supposed to deviate too much from previous measurement and results. Take the fourth case of experiments (Case IV, without vegetation), the velocity and turbulence distribution should be consistent with the results obtained by the previous authors (Obach, 2011; Macvicar and Best, 2013). But unfortunately, the results (Reynolds shear stress and TKE distribution) are so different from the previous results that I cannot understand how such measurements were obtained. In particular, the results of the fourth case (without vegetation) are expected to be significantly different from those of the third case (with vegetation), but I can't see it from most measurements in Figures 5 and 6 (the vertical shapes should be totally different). On the contrary, to some extent, the results of these two cases are more or less similar. This phenomenon makes me more difficult to understand the results. For the flow velocity distribution results, the distribution in Figure 4 is too small to clearly observe the difference between the cases, so I cannot evaluate the results of the velocity profiles. In summary, I have a critical concern about these experimental measurements. The authors also did not explain why they obtained different results from previous studies.
- Following the question above. In addition to the questionable measurements, there are plenty of studies on the influence of vegetation on flow characteristics, the authors should have discussed their results in detail in terms of the effect of topography and the effect of vegetation, instead of simply telling the reader their results. For this paper, such a discussion would be very important. Unfortunately, the authors do not specifically discuss their results. The conclusions follow the results section.
- This paper missed many key details, such as how the authors processed the measured ADV data, based on which methods (specific steps), and equations are used to calculate the shear velocity and wake parameters. How the data from different points were processed to get a cross-sectional averaged parameter in Figure 4. These details are crucial for understanding the authors' results, but detailed information is not provided.
Based on these three major concerns, I feel that this paper is inappropriate to be considered for publication at this time. There are also some writing issues that need to be paid attention to by the authors. The flow velocity distribution in Figure 4 is too small to be identified and there is no legend for the line graph in Figure 4, making it difficult for readers to understand. The authors did not define the coordinate for the velocity, and thus the shear stress results in Figure 5 are not clearly defined. Some unnecessary explanations in the paper could be removed (e.g., from line 384 to 392).
References:
Obach, L.M., 2011. The hydrodynamics of pool-riffle sequences with changing bedform length (Master's thesis, University of Waterloo).
Bruce MacVicar,Jim Best, 2013, A flume experiment on the effect of channel width on the perturbation and recovery of flow in straight pools and riffles with smooth boundaries, 118(3), 1850-1863.
Author Response
Please see attached discussion letter.
Thanks!
Author Response File: 
Author Response.pdf
Reviewer 2 Report
The manuscript should be revised based on the attached file.
Comments for author File: Comments.pdf
Author Response
Please see attached discussion letter. Thanks!
Author Response File: Author Response.pdf
Reviewer 3 Report
The manuscript “Interaction of Irregular Distribution of Submerged Rigid Vegetation and Flow within a Straight Pool” addresses the turbulent flow field in a flume with the presence of submerged rigid vegetation elements in the channel bed of a straight pool based on laboratory experiments, which is an interesting topic within the scope of “water” (although a little bit too specific). The work is well written and is based on a fine set of laboratory data. However, the structured could be improved, in particular:
- The abstract should reflect all the parts of the research paper and therefore should provide some background to the study, the motivation, and objectives.
- The introduction will benefit from a change in the structure, some ideas are repeated along the text.
- The conclusions should identify research limitations and explore the implications of the results to the “real life “environment. These implications are correctly identified and discussed in the introduction.
Minor comments:
Line 36 - The classification of changes in nutrients in the environment as positive or negative is a rather naïve way of looking to these problems.
Line 48 – “Baptist et al. (2007)” is not the adopted reference citation style
Line 68 – “flow to rotate clockwise” – it is an ambiguous description; does it not depend on the flow direction?
Line 176 – how can the flow depth be measured with an “accuracy of 1 mm” if the median grain size of the bed material is larger than 10 mm?
Line 262 – do not understand the reference to Table 1.
Figure 4 – Legend should include the symbology of the different curves.
Author Response
Please see attached discussion letter. Thanks!
Author Response File: Author Response.pdf
Round 2
Reviewer 1 Report
In my last review comments, I emphasized my concern about the measurement results, as I found that the authors' measurements were different from those of existing research. The authors reply to me that they have long experience with flow measurements, and compared their “results” with other researchers to prove the reliability of their “results”.
The interesting thing is that their results (revised manuscript) were significantly different from the results shown in their original manuscript. Yes, figure 6 in the revised manuscript looks much better now, but the question is why the results are so different? Unfortunately, the authors did not explain this inconsistency. In this regard, I think it is no longer just a matter of data reliability.
Author Response
Dear Reviewer:
Please see attached discussion letter.
Thank you!
Jueyi Sui
Author Response File: 
Author Response.docx
Reviewer 2 Report
I just had a look at the revised version of the manuscript. In my view, it has been sufficiently improved and can be accepted in present form.
Author Response
Thank you for re-reviewing our paper!
Jueyi Sui
