GIS-Based RUSLE Reservoir Sedimentation Estimates: Temporally Variable C-Factors, Sediment Delivery Ratio, and Adjustment for Stream Channel and Bank Sediment Sources

Round 1

Reviewer 1 Report

The paper has many shortcomings that must be corrected. You wanted to show a lot of things using various statistics of a large number of catchment areas, but in the end you did not show them well in the paper itself.

The abstract is too long and should be shortened and the key information that will interest the readers of this paper to continue reading the entire paper should be stated.

Supplemental Material should be presented in a separate word, excel or PDF document and not in the same one where the work itself is.

Given that you worked on the RUSLE model in a GIS environment, and you mention the very name of GIS, which represents a powerful tool for spatial analysis, you must show for each factor used in the RUSLE model spatially, that is, show maps with the values of those factors.

In your paper, you are based on factor C in several time series, which is related to land cover and land use. In addition to the C factor that you need to map, you also need to map land cover/land use to give the reader a visual representation of it.

Land cover and factor C was obtained on the basis of which satellites? How was it obtained? In what resolution? Did you digitize satellite images or did you apply some classification model such as supervised unsupervised or some AI?

Did you use facto C for the period 1981 to 1997? Why didn't you include some current situation in the analysis?

You have to create a lot of maps and it's up to you whether you want to put them in the paper itself or put them in the Supplemental Material

The factor R is not clearly explained as it was obtained in this paper, and today there are different formulas with the application of different rain intensities from 15 min, 30 min, to average daily, monthly or average yearly rains.

Is there a spatial display or map for the SDR model that was obtained on the basis of all four formulas?

Soil loss using the RUSLE model should be shown on the basis of maps.

In the Conclusion chapter, you should not cite other authors, the conclusion is poorly written, it should emphasize the work itself, and this work does not show that.

Author Response

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Author Response File: Author Response.docx

Reviewer 2 Report

The manuscript GIS-Based RUSLE Reservoir Sedimentation Estimates: Temporally Variable C-Factors, SDR, and Adjustment for Stream Channel and Bank Sediment Sources has an interesting technical novel but needs to clarify some points before being published. 

Major review

1)     In the introduction, I suggest describing in greater detail the context of the work in relation to the application of RUSLE in small river basins. Some articles that may help are:

https://doi.org/10.1007/s12040-013-0276-0

https://doi.org/10.3390/agronomy10060777

https://doi.org/10.3390/hydrology10010007

https://doi.org/10.1016/S0341-8162(99)00067-3

https://doi.org/10.1002/ldr.646

2)     The authors need to explain why they chose the dates 1981, 1985, 1989, 1994, and 1997 for land cover.

3)     Insert a flowchart at the beginning of the methodology to explain the research steps.

4)     In topic 2.1.3. Stream Corridor Variables is mentioned "... was manually digitized along the main channel...". Corridors were scanned manually or a buffer was made. Manually digitized does not guarantee the constant 50m accuracy mentioned in the text.

5)     Lines 295-302 “The R- and P-factor images were developed 295 by first creating a “blank” image (0 for background values and 1 for the watershed area within and including the watershed boundaries) for each watershed. The R-factor images were then created by reclassifying the values of 1 to 225 based on the isoerodent map in [12]. The within-watershed values of 1 were not reclassified for the P-factor images as this is the recommended value when the support practice(s) used is/are unknown. All images for each watershed were resampled to match the spatial attributes for each water-301 shed’s DEM.”

The explanation of the origin and steps to generate the factors of the RUSLE equation is very poor and needs to be reformulated.

Minor review

Check the form of citation throughout the manuscript. For example, the use "[31] mentions in his study...." is wrong, the correct one is "Gordon [31] mentions in his study..." It is necessary to mention the author's name in this type of citation.

Check the correct citation of sites in the references.

[30] http://climate.ok.gov/index.php/climate/climate_normals_by_county/local_data. (Accessed August 7, 2023).

Author Response

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Author Response File: Author Response.docx

Reviewer 3 Report

This paper demonstrates a commendable effort in utilizing the RUSLE model for estimating reservoir sedimentation, featuring several noteworthy strengths, as well as a few lingering questions. The authors thoroughly address various watershed characteristics that may impact the outcomes, exhibiting a commendable awareness of the model's limitations in the context of this analysis. Their comprehensive methodological approach encompasses a diverse array of techniques, ranging from traditional methods to contemporary GIS tools like TerrSet.

However, it is important to highlight a critical limitation identified in the study: the RUSLE model appears to struggle in adequately accounting for sediments originating from gullies, stream channels, and stream banks. This limitation is not only evident in the present research data but is also supported by existing literature. Consequently, despite the paper's robust data and meticulous analysis, it appears that the intended objectives and desired outcomes were not fully achieved.

To enhance the impact and reliability of this research, it is recommended that the authors explore potential solutions or alternative models in the future that may better address the challenges associated with gully, stream channel, and stream bank sediment sources.

It is noteworthy to emphasize that while the research's chosen results may not fully align with the intended objectives, this divergence primarily pertains to the model's inherent limitations rather than the rigor of the methodology employed. In light of this, the authors should be commended for their robust approach to the study, as it provides valuable insights into the practical challenges of utilizing the RUSLE model in this context.

In conclusion, the research and methodology presented in this paper are commendable, contributing valuable knowledge to the field. The disparity between the intended and actual results underscores the importance of recognizing the model's limitations, which should serve as a valuable reference for future investigations in this domain.

Fig. 1 Please reconsider the map presentation as it currently lacks clarity regarding the study area's location, the point under Oklahoma city.

Line 198: Please provide an explanation for the necessity of manual digitization in this instance. Given the context, it would be reasonable to expect that a 50-meter buffer around the thalweg line could have been used instead.

Line 215: When you mention "visually identify," it's important to provide a more precise definition for what constitutes "somewhat geomorphically homogeneous" to enhance the clarity of your methodology.

Line 319: Please include an explanation for the specific choice of years mentioned in this section. Clarify why these particular years were selected for the study.

In a broader context, the study appears to encompass morphological and vegetation characteristics effectively. However, it is worth considering for future the potential impact of including extreme precipitation values and flood events in your analysis, as these factors could significantly enhance the comprehensiveness of your research.

Author Response

Please see attachment.

Author Response File: Author Response.docx

Round 2

Reviewer 1 Report

The authors corrected the paper after the reviewers' comments and suggestions. The paper can be published in a journal.

Reviewer 2 Report

The authors made the necessary corrections, improving the final presentation of the manuscript. I accept the manuscript in its current form.