Review Reports - Detection of Aguadas (Ponds) Through Remote Sensing in the Bajo El Laberinto Region, Calakmul, Campeche, Mexico

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

Please see the attached file.

Comments for author File: Comments.pdf

Author Response

Major changes were made in some sections. A new data source was included, which are the orthophotos from INEGI, in order to make comparisons between the new data sources and previous ones such as aerial photography. Additionally, changes were made to all the figures, tables with data flow were included, and spelling, writing, and style were corrected. Two new images were added, Figures 2-4, with aerial views and on-site views of the aguadas, as well as of excavations. Some sections were reordered, as suggested by other reviewers.

Author Response File: Author Response.docx

Reviewer 2 Report

Comments and Suggestions for Authors

In the abstract, the sources of imagery data for identifying aguadas are described, but the methods used to identify aguadas are not elaborated.
The titles of Subsections 1.1, 1.2, 1.3, and 1.4 are too brief and should be revised to clearly indicate the main content of each subsection, similar to the descriptive style of Subsection 1.5.
The Introduction section overly emphasizes earlier studies and lacks sufficient mention of key research from the past five years, failing to reflect the latest advancements in the field.
In Section 2. Materials and Methods, can a technical flowchart be added to enhance the readability of the paper?
In Lines 522-523, it is stated that "larger aguadas are more easily detected," but this claim lacks supporting evidence from figures or tables in the text. Please provide relevant data
In Line 591, the assertion "it is anticipated that in areas where only satellite imagery is available, at least 10-15% of the aguadas remain undocumented" relies on estimated values. Please provide empirical evidence to justify both the 10-15% range and the claim itself.
The text does not explicitly clarify how data of varying spatial resolutions affect the detectability of small aguadas.
Please analyze the relationship between aguadas distribution and geomorphological features by incorporating topographic data .
The explanation of shape classification in the Results section is insufficient (e.g., why circular and rectangular shapes dominate in proportion? Does this reflect anthropogenic modifications?).
The Discussion section (4) inadequately compares existing studies and fails to emphasize the advantages of this study's multi-source data fusion approach.
In Figure 9, the total count for "Planet IR 12" is listed as 69, whereas in Table 3, the number of identified aguadas for "Planet 12/2001" is reported as 74. Please verify and reconcile this discrepancy. Please also verify the consistency between "Planet IR 4" in Figure 9 and "Planet 4/2001" in Table 3.
In Lines 380-381, the text states: "The study employed image sets from the Sentinel 2 constellation on May 3, 2021, and from Planet on April 12 of the same year." However, Table 3 lists Planet data as spanning April and December 2001. Please confirm whether this is a typographical error in either the text or the table, and correct the inconsistency accordingly.
Figure 10 appears multiple times; please verify the numbering of figures/tables. In Lines 527, 531, and 537, Figures 12, 13, and 14 are referenced but not present. Please ensure consistency between figure labels and their corresponding context in the text. Additionally, confirm whether the numerical expression in Figure 10 is correct. For example, should "55,6%" be revised to "55.6%"?
The text in Figures 4 to 8 is blurry or unclear, making it difficult to read. Upon the first mention of software names, include the software version in parentheses (e.g., "Software X (v1.0)"). Please ensure the x-axis in Figure 9 is properly labeled (e.g., add units or a descriptive title if missing). In Table 2, under the "lidar (PABEL)" column, the entry for "Spatial resolution" is listed as ".50m". Please check whether the leading dot (.) is superfluous and verify the numerical accuracy . Similarly, review Table 3 for similar issues (e.g., formatting, numerical values, or labels).

Author Response

Author Response File: Author Response.docx

Reviewer 3 Report

Comments and Suggestions for Authors

General Comments:

This manuscript is a comparative study of the detection and the classification of aguadas (ponds) in the Calakmul region using different remote sensing methods (lidar-based lidar, RGB and NIR).

The topic of this article is therefore well adapted in this journal MDPI Remote Sensing. However, the quality of the Figures/Tables and the general discussion should be strongly improved before a possible publication in this journal. The influence of the “moist semitropical forest” and “high to medium evergreen forest” conditions in this region on the results is not well described in the discussion section. One missing point in the discussion/conclusion is the potential use of the Surface Soil Moisture (SSM) at high spatial resolution (1km) (SMAP or SWOT) in a complementary fashion to these data.

For these reasons, I suggest publication but after a strong improvement of the discussion/conclusion and after the clarification of the text and illustrations (see below) in a major revision of the manuscript.

1/ Modifications of the Figures/Tables:

Table 2: replace please “passive” by “passive”
Table 2: why only “0.5 m” of spatial resolution is used in The Study and “0.5m and 2m” of resolution in Table 3 ?
Table 3: why the result of SLRM R20 (given in Figure 9) is not included in Table 3 ?
Figure 9: add in the legend “in the studied area”
Figure 9: explain that “Planet IR 04” is the Planet image on April 12, 2021. Can you give is the precise date of “Planet IR 12” ?
Figure 10: not clear, add the different legends (by shape, by topographic position, by canopy cover, by origin) differently in one legend for one Figure.
Figure 11: write the legend of spatial scale in English (kilometers)

2/ Text:

Line 391 and 484 : explain that “SLRM R20” is SLRM with a radius for trend assessment of 20 pixels (the default value), perhaps in the list of Abbreviations
Line 516: correct the number of the Figure (Figure 10 instead of Figure 11)
Line 676: Figure 1 instead of Figure 9 ?
Line 610: Add “due to their resolution and their representation of topographic relief”

Author Response

Author Response File: Author Response.docx

Reviewer 4 Report

Comments and Suggestions for Authors

This study integrates LiDAR and multi-source satellite imagery to systematically analyze the distribution of aguadas (ponds) in the Bajo El Laberinto region of the Calakmul Biosphere Reserve, Mexico, with innovative insights into ancient Maya water management. While the methodological framework is robust, several sections require clarification to enhance scientific rigor. A major revision is recommended.

The manual identification process is well-documented, but the rationale for dismissing automated methods (e.g., SAM, NDWI) lacks quantitative validation (e.g., precision/recall metrics). The authors should include a comparative analysis of manual vs. automated detection accuracy or elaborate on canopy/water dynamics affecting algorithm performance.
Satellite imagery analysis relies on single-date acquisitions (e.g., April 2021 for Planet), ignoring seasonal variations in aguada water levels. The authors should incorporate multi-temporal imagery to assess detection consistency across dry/wet seasons.
Anthropogenic origin claims depend heavily on morphology; direct archaeological evidence (e.g., excavation data) is underutilized. Integrate stratigraphic profiles or artifact distributions from field studies (e.g., Yaxnohcah cores) to strengthen arguments.
Inconsistent figure references (e.g., "Figure 9" and "Figure 10" in text vs. mismatched captions). Reorganize figures with sequential numbering and ensure alignment between text and visuals.
Data sharing protocols are vague, lacking specifics on repository access or ethical restrictions. Clarify data access procedures (e.g., DOI links) or provide sample datasets as supplementary material.

Author Response

Author Response File: Author Response.docx

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

Please see the attached document.

Comments for author File: Comments.pdf

Author Response

Original Submission

1.1. Recommendation

Reconsider after major revisions

Comments to the Authors

Ms. Ref. No.: Remote Sensing - 3634351

Title: Detection of Aguadas (Ponds) Through Remote Sensing in the Bajo El Laberinto Region, Calakmul, Campeche, Mexico

Authors: Alberto G. Flores Colin, Nicholas P. Dunning, Armando Anaya Hernández, Chris topher Carr, Felix Kupprat, Kathryn Reese - Taylor, and Demian Hinojosa-Garro.

2.1. Major Co mments

Introduction. The authors present a list of studies done in remote sensing of aguadas, which is greatly appreciated to better gain insight into the topic. However, it is un clear what research

gap this study tries to ﬁll, nor what the research goals are . Some of those elements are somewhat mentioned in the last paragraph but are not clearly stated. I suggest reworking this paragraph to make sure those elements are incorporated .

Your comments were addressed. This section was reorganized according to your suggestions.

Methods. The number of visualization methods is not consistent throughout the manuscript. The authors mentioned they used twelve visualizations; however, I count thirteen of them: hillshade, SLRM, VAT, orthophotos, Bing Maps, ESRI, Google Earth, Sentinel 2 RGB, Sentinel 2 - NIR -G- B, Sentinel - 2 IR, Planet RGB, Planet - NIR -G- B, Planet IR. The last one, Planet IR is not mentioned in Figures 10 - 14 but in Figure 9. In the Minor Comments section below , I provide speciﬁc details on where I found these inconsisten cies. Please clarify and modify the manuscript accordingly.

Your comments were addressed. The inconsistencies in the names of the sources used have been corrected; there are only 12 sources used.

Results. The authors mentioned this time the number of historical aguadas identiﬁed by Garcia et al. (2002), which serves as a reference to quantify the eﬀectiveness of the visualization techniques. However, when comparing the eﬃ cacy of the methods, they mainly do it against the DEM visualization, rather than comparing the visualizations against the results of Garcia et al.

A second issue with the Results section I mentioned in my initial review is that it lacks a statistical analysis to determine whether the diﬀerences observed between the visualizations are statistically signiﬁcant. For instance, is the diﬀerence in the number of aguadas identiﬁed using Planet RGB vs. Planet IR statisticall y signiﬁcant? Without the statistical analysis/test, the results are only descriptive.

Your comments were addressed. The first part of this observation was addressed. The statistical analysis of the data from the contrasted sources was conducted.

A third issue is the lack of validation of the results. It is possible that what appears as an aguada in the image is not an aguada in the ﬁeld. However, validation could be easily accomplished by comparing the number of aguadas identiﬁed by each visualization method to that of Garcia et al. That is, how many of the aguadas Garcia et al. identiﬁed were also correctly identiﬁed by each of the visualizati on methods? I believe there could be aguadas partially covered by vegetation that Garcia et al. identi ﬁed , but they could not be determin ed by the visualization methods evaluated. This analysis can also help the author quantify how many partially covered aguadas were not detected by their visualization methods, which is a limitation of the methods and should be addressed later in the D iscussion.

Your comments were addressed. A section was added that includes field verification, where the verified water sources are shown along with some images taken with a drone.

Discussion. In this section , the authors used the best three visualization method s to identify aguadas in a larger area. This information is valuable bu t should not go in the Discussion ; it must go in the Results section. With this change, not much is left in this section as it is in its current state. The Discussion section lacks 1) the interpretation of the results, 2) the explanation of their signiﬁcance, and 3) how they relate to existing research.

Your comments were addressed. This section was reorganized and statistical analyzes were added.

2.2. Minor Comments

Line 50. Spelling mistake? ‘documentininthe’ I think the authors meant ‘documenting the’

Your comments were addressed.

Line 61. Remove ‘Introduction to’ from the subtitle. This is in the introduction section, so it is implied that.

Your comments were addressed.

Line 106. Since the Yaxnohcah - Pared de Los Reyes Area is within the Bajo El Laberinto Region, this section should be numbered 1.1.1.

Your comments were addressed.

Line 111. Spelling mistake ‘arround’. I think the authors meant ‘around’.

Your comments were addressed.

Line 136. Please s pecify in the text whether it is Figure 2A or 2B.

Your comments were addressed., refered to both figures

Line 137. Move Figure 2 to section 1.2 , where it was ﬁrst mentioned.

Your comments were addressed.

Line 138. Since the Calakmul Area is within the Bajo El Laberinto Region, this section should be numbered 1.1.2.

Your comments were addressed.

Line 150. Please s pecify in the text whether it is Figure 2A or 2B.

Your comments were addressed.

Line 163. Figure 2 . Please s pecify which area each photo belongs to .

Your comments were addressed.

Line s 203 and 238. The paragraph on line 203 and the one on line 238 contain similar information. Please combine into one single paragraph. Also, remove ‘As noted above’ because the categorization of aguadas has not previously been discussed.

Your comments were addressed.

Line 256. The way this sentence is written makes me believe only ﬁve aguadas were evaluated, when in reality , many aguadas were identiﬁed using the diﬀerent visualization methods. I suggest clarifying that ﬁve aguadas with varying vegetation types were selected as examples to illustrate the eﬃcacy of the various visualization methods.

Your comments were addressed.

Line 258. I believe the authors meant Figure 4 instead of Figure 3.

Your comments were addressed.

Line 2 67 . Move Figure 3 to section 1.4 , where it was ﬁrst mentioned (Line 208) .

Your comments were addressed.

Line 302. Move Figure 4 to section 2. Materials and Methods , where it was ﬁrst mentioned (Line 258)

Your comments were addressed.

Line 364. Move Figure 6 to section 2.2 , where it was ﬁrst mentioned.

Your comments were addressed.

Lines 373 - 374. I believe the authors meant to say that healthy vegetation appears red when visualized in a false color image (NIR, R, G) - not in NIR only. Please rephrase.

Your comments were addressed.

Lines 378 - 379. Specify if the color variations in water correspond to a natural or false color image.

Your comments were addressed.

Line 384. This section should be labeled 2.3.1 because it is a subsection of the satellite images and visualization techniques.

Your comments were addressed.

Line 436. Move Figure 7 to section 2.3 , where it was ﬁrst mentioned.

Your comments were addressed.

Line 454. The authors mentioned they used twelve visualizations; however, I count thirteen of them: hillshade, SLRM, VAT, orthophotos, Bing Maps, ESRI, Google Earth, Sentinel 2 RGB, Sentinel 2 - NIR -G- B, Sentinel - 2 IR, Planet RGB, Planet - NIR -G- B, Planet I R .

Your comments were addressed. The nomenclature data for each of the visualizations has been corrected, there are only 12 in total.

Line 466. Move Figure 8 to section 2.4 , where it was ﬁrst mentioned.

Your comments were addressed.

Line 470. Move Table 2 to section 2.4 , where it was ﬁrst mentioned.

Your comments were addressed.

Line 503. This section mentions that ﬁve aguadas were used as examples to illustrate the diﬀerences in visualizations. However, only four are described (Big Tom, Fidelia, Bodal, and 250). Please add the description and visualizations of A guada 259. Furthermore, I would like to see in this section a table that shows the ﬁve aguadas (columns) and the thirteen visualizations (rows) , and check marks to indicate when the authors considered the aguada was ‘successfully’ identiﬁed and tallied.

Your comments were addressed., the suggested table was added

Line 507. I believe the authors meant Table 3 instead of Table 2.

Your comments were addressed.

Line 517. The ﬁrst line of the paragraph corresponds to Aguada Fidelia , and it should be part of the previous paragraph.

Your comments were addressed.

Line 530. Move Figure 9 to section 2.5 , where it was ﬁrst mentioned. Furthermore, the visualizations in the ﬁgure do not correspond to the ones presented in this section. For instance, the orthophoto and the Planet NIR -G- B visualizations are missing, and two Planet IR images are included . Please add the orthophoto and Planet NIR -G- B visualizations to the ﬁgure and remove the additional Planet IR . In addition , this image appears truncated in the manuscript ; make sure it shows correctly in the ﬁnal version.

Figure 9 is the first flowchart, Are you sure that's the image?

Line 542. T he fact t hat the aguada was partially covered by a cloud on the Bing satellite image is mentioned twice. Rephrase.

Your comments were addressed.

Figures 10 - 13 should be moved to section 2.6 , where they were ﬁrst mentioned. Furthermore, these ﬁgures only show twelve out of the thirteen visualizations. By comparing Figures 10 - 13 with Figure 9, I can see that Planet N IR is missing. Please add this visualization to all the ﬁgures.

The figures were moved to their corresponding section. I think there is a confusion with Figure 9. In version 2, it is a flowchart, it does not include images of the aguadas. There is probably some confusion with the previous version due to the use of track changes. In the PDF, there is a version without track changes that is clearer.

Line 550. I think the authors meant ‘identiﬁability’ instead of ‘identiﬁably’.

Your comments were addressed.

Line 558. Imagery is deﬁned based on ﬁve types of resolution. Specify that this is the ‘spatial’ resolution and remove ‘every pixel’; this is implied.

Your comments were addressed.

Line 563. Please specify what kind of resolution you are referring to in the expression ‘resolution of color mosaic ’; are you referring to the spectral resolution , spatial resolution, the diﬀerent shades of a color, or something else?

Your comments were addressed.

Line 568 - 569. It is unclear if the authors are referring to the Sentinel VNIR visualization or the Sentinel SWIR visualization; please specify. Furthermore, I do not get the math of the VNIR visualization being ‘more than twenty - ﬁve percent lower than those of the lidar DEM. Figure 14 indicates that the lidar DEM identiﬁed 99 aguadas, and Sentinel VNIR identiﬁed 53 aguadas. That means th e aguadas identiﬁcation using Sentinel VNIR was about 47% lower than lidar DEM. And in the case of Sentinel SWIR, it w as 60% lower than lidar DEM. Please explain your approach to this calculation.

Your comments were addressed.

Figure 14. This ﬁgure is missing how many aguadas were identiﬁed using the Planet NIR visualization.

It is in figure 14, it is the 4th row from the bottom up.

Line 625. The percentages of circular and rectangular aguada shapes do not correspond to those in Figure 16. Please, revise.

Your comments were addressed.

Line 626. Technically, irregular aguada shapes are not over 10% according to Figure 16. Please, revise.

Your comments were addressed.

Line 628. I think the authors meant Figure 16 instead of Figure 14. However, I suggest removing the last sentence from that paragraph.

Your comments were addressed.

Line 631. Table 4 oﬀers the same information provided by Figure 14 and other portions of the manuscript. I strongly recommend removing Table 4 from the manuscript.

Your comments were addressed., table was removed.

Line 633. Please deﬁne in this paragraph the diﬀerent topographic position s of aguadas according to the description in Figure 17. For instance, what is the diﬀerence between Stream and Bajo/Stream and between Pocket bajo, Bajo margin, and In Bajo ?

Your comments were addressed.,although Pocket bajos were defined in section 3.1

Line 638. Instead of saying 11% in larger bajos, say 11% in Bajo to match the text of Figure 17.

Your comments were addressed.

Line 639. Instead of stream channels, say Bajo/Stream to match the text of Figure 17.

Your comments were addressed.

Line 670. Please remove Figure 15 , as this one present s the same information as Figure 16.

Your comments were addressed.

Line 727 - 747. It is not customary to have bullet points as part of the results. I suggest that instead of having the bullet points, the authors nest the statements made within the text. For example, the last bulleted point can be annexed to the paragraph on line 613. Otherwise, this portion feels like a conclusion.

We consider this bulleted section important as it highlights the findings we discovered during the research process, and it is also something the editorial requests, so we believe it is important to keep it. The final part that seemed like a conclusion was removed.

Lines 750 - 768. The information provided here should be part of the Results, not the Discussion.

Your comments were addressed., the information was moved into results section.

Line 756. Figure 20 should be moved to the section where it is mentioned.

Your comments were addressed.

Line 794. Specify which methods were used in the ﬁgure caption.

Your comments were addressed.

Line 796. First, Figure 21 should be moved to the section where it is mentioned. Second, according to the text, three visualization methods were used to identify aguadas in the Bajo El Laberinto region; however, l idar is includ ed in the ﬁgure, which is misleading. Third, I ﬁrm ly believe that Figure 21 is unnecessary, as the process is clearly explained in the text; thus, I suggest removing it from the manuscript.

Ok, Figure 21, second flowchart, was removed of the text.

Author Response File: Author Response.docx

Reviewer 2 Report

Comments and Suggestions for Authors

The author has revised the manuscript according to the review comments.
Regarding Figures 15, 18, and 19, it seems that the previous versions of the figures have not been completely removed. The titles for Figures 20 and 21 should be placed immediately below the images. Accepted after revisions.

Author Response

Response:

All changes were made, figures were removed, and titles were corrected. Figure numbers change after additions of new figures.

Reviewer 3 Report

Comments and Suggestions for Authors

Answer to the reply : "Major changes were made in some sections. A new data source was included, which are the orthophotos from INEGI, in order to make comparisons between the new data sources and previous ones such as aerial photography. Additionally, changes were made to all the figures, tables with data flow were included, and spelling, writing, and style were corrected. Two new images were added, Figures 2-4, with aerial views and ground-level views of the aguadas, as well as of excavations. Some sections were reordered, as suggested by other reviewers."

indeed, I notice some significant improvements in this new version. However, hereafter are some additional corrections to make :

Fig. 1, 2 and 4 : coordinates (latitude, longitude) should be added in both images (included in the inset called "location"). In the legend, the inset should be also described (which software was used, Google earth ?).

Fig. 5, 10, 11, 12 and 13: "A) Simple unidirectional hillshade". Precise the chosen direction please.

Fig. 9 : the text "data sources with better results" is partially hidden (perhaps only a problem during the conversion of word to pdf format ?). What means "MDE" ? perhaps "DEM" ?

Fig. 14 and 15 : add the number of the reference of Garcia et al. (64) in the Figure and the legend.

Fig. 18 and 19 : Problem of the chart : perhaps only a problem during the conversion of word to pdf format ?

64. García Gil, G.; Palacio Prieto, J.L.; Ortiz Pérez, M.A. Reconocimiento geomorfológico e hidrográfico de la Reserva de la Biosfera 996
Calakmul, México. Investig. Geográficas 2002, 7–23.

Text line 16-17 : "using remote sensing various techniques"

Text line 21 : "while lidar data provides superior topographic details"

Text line 50 : "documenting inthe distribution"

Text line 290 : replace please "by Kokalj and colleagues in [73–75]" by "by Kokalj et al. in [73–75]"

Text line 424 : "Sentinel 2 images are open access and have a historical archive that goes from 2015 to the present". Precise (or add an additional reference to) the link to the official website https://www.sentinel-hub.com/explore/copernicus-data-space-ecosystem/

Author Response

Comments

indeed, I notice some significant improvements in this new version. However, hereafter are some additional corrections to make :

Fig. 5, 10, 11, 12 and 13: "A) Simple unidirectional hillshade". Precise the chosen direction please.

Fig. 9 : the text "data sources with better results" is partially hidden (perhaps only a problem during the conversion of word to pdf format ?). What means "MDE" ? perhaps "DEM" ?

Fig. 14 and 15 : add the number of the reference of Garcia et al. (64) in the Figure and the legend.

Fig. 18 and 19 : Problem of the chart : perhaps only a problem during the conversion of word to pdf format ?

Text line 16-17 : "using remote sensing various techniques"

Text line 21 : "while lidar data provides superior topographic details"

Text line 50 : "documenting inthe distribution"

Text line 290 : replace please "by Kokalj and colleagues in [73–75]" by "by Kokalj et al. in [73–75]"

Response:

The article underwent substantial modifications at the behest of one of the reviewers, and all of your comments were addressed during this process. Several figures were removed, new figures were introduced, and new sections were incorporated. To view all modifications, please refer to the file containing the track changes.