Review Reports - Potentials and Limitations of Fluviomarine Pollen Records to Reconstruct Spatiotemporal Changes in Coastal Ecosystems During the Holocene: A Case of Study from Ría de Vigo (NW Iberia)

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

General comments

A useful and rather complete study of modern pollen assemblages in the Ria de Vigo, with a detailed comparison to vegetation. However, a real discussion is missing. See comments below.

Line 82-83: Concerning Holocene hiatus in coastal records during the Holocene, see the Bay of Brest: two gaps (5.9–4.8 ka BP and 3–2.4 ka BP). See the other recent paper of Valero et al., 2025 Holocene paleoenvironmental reconstructions in western Brittany (Bay of Brest): Part II–A 7 kyr human-environment story with a focus on the Neolithic-Bronze Age transition. The Holocene https://doi.org/10.1177/0959683625131363

In the discussion, at the moment you limit yourself to very valuable observations, but no more. What are the lessons derived from your observations, section by section (5.1, 5.2, 5.3, etc)? How does it compare to other studies elsewhere in the world? Thus the manuscript as it stands is more a report than a scientific paper. This should be easy to address, in regards to the quality of your data.

For example, see modern samples in the Brest Bay, France

1) Lambert C, Vidal M, Penaud A, et al. (2017) Modern palynological record in the Bay of Brest (NW France): Signal calibration for palaeo-reconstructions. Review of Palaeobotany and Palynology 244: 13–25;

2) and also the very recent paper of Valero et al 2025 Holocene paleoenvironmental reconstructions in western Brittany Bay of Brest: Part I – Understanding the spatial distribution of palynological records. The Holocene https://doi.org/10.1177/09596836251313

Points of detail

Do not provide the pollen diagrams (as they are results) in the “Materials and Methods” section, but they should be called and shown only the “Results” section. In general, revise the position of the figures in the text. For example, fig. 11, 12 and 13, should move to the discussion.

Amaranthaceae/Chenopodiaceae may be replaced everywhere (text, tables and figures) by Amaranthaceae.

Concerning Pinus subgenus Pinus, is it necessary to provide such a level of taxonomy, when you do not mention any other subgenera?

In general provide more details in the figure and table captions.

Fig. 1: Add a figure with the location of Spain in Europe for the international reader

Add the source for the maps. Is it Google Earth?

Fig. 3 title: Nenos with a capital letter

Fig. 3: besides the pinewood in pink, how are the other vegetation types shown?

Fig. 4 caption: a), b) and c) are not shown on the figures.

Fig. 4: is the extra-local vegetation contained in the green line? Where is then the regional vegetation? Actually how are the different vegetation types shown on fig. 4?

Fig. 8: explain what is the thick horizontal line separating the samples.

Fig. 10 caption: explain the difference between A and B.

Line 506: it is difficult if not impossible to identify heather on fig. 4.

Table 5 caption: explain what is the green colour, what is <<?

Author Response

Reviewer 1:

General comments

A useful and rather complete study of modern pollen assemblages in the Ria de Vigo, with a detailed comparison to vegetation. However, a real discussion is missing. See comments below.

Thank you very much for you detail review and useful comments

A very interesting article that has just been recently published, and in a fluviomarine context like ours. We have include it in our discussion. Thank you.

We have tried to include those and other issues in a new section of the discussion: 5.6. Lessons for interpretations of pollen records from shallow seabed sediments.

For example, see modern samples in the Brest Bay, France

Thank you. These and other references are now included in the introduction and discussion

Points of detail

Changes done in the new version of the manuscript. Some figures have been renumbered and moved to the most appropriate position in the manuscript.

Amaranthaceae/Chenopodiaceae may be replaced everywhere (text, tables and figures) by Amaranthaceae.

Of course, you are right. Changes are made both in the texts and in the figures.

Concerning Pinus subgenus Pinus, is it necessary to provide such a level of taxonomy, when you do not mention any other subgenera?

The identification key in Moore et al. (1991) we followed for pollen determination and cited in the manuscript differentiates between Pinus subgenus Pinus (=Diploxylon) and Pinus subgenus Strobus (=Haploxylon). Thus, we used this nomenclature across the text. Reference below the first time it appears in the text has been specified.

[59] Moore, P.D., Webb, J.A., Collinson, M.E. Pollen Analysis, Second edition. Blackwell Scientific Publications 1991, Oxford, England.

In general provide more details in the figure and table captions.

Fig. 1: Add a figure with the location of Spain in Europe for the international reader

Add the source for the maps. Is it Google Earth?

Fig. 3 title: Nenos with a capital letter

Fig. 3: besides the pinewood in pink, how are the other vegetation types shown?

Fig. 4 caption: a), b) and c) are not shown on the figures.

Fig. 4: is the extra-local vegetation contained in the green line? Where is then the regional vegetation? Actually how are the different vegetation types shown on fig. 4?

Fig. 8: explain what is the thick horizontal line separating the samples.

Fig. 10 caption: explain the difference between A and B.

Line 506: it is difficult if not impossible to identify heather on fig. 4.

Table 5 caption: explain what is the green colour, what is <<?

All the above issues have been modified accordingly in the amended version of the text. Thak you again for your very detailed review.

Author Response File: Author Response.docx

Reviewer 2 Report

Comments and Suggestions for Authors

The coastal areas are a complex environment connecting terrestrial and marine. Aiming to detect whether the pollen records from fluviomarine sediment could be used to reconstructed the vegetation in surrounding area, this study collected and analysed 61 pollen samples from coastal lagoons, upland lakes and seabed deposits in Ría de Vigo (NW Iberia). They concluded that shallow seabed pollen can provide useful information for understanding the vegetation cove around the area. However, the selection of sampling sites combining multi-context records are important for accurate reconstruction of paleovegetation. This study provides meaningful references for paleovegetation reconstruction in the coastal areas. I have some concerns as follows.

1. The main topic of this paper is to evaluate the pollen representation for vegetation in coastal zones. However, too much complicated information is listed in the Introduction, which affects the reading, such as lines 87-111. It is recommended to focus on the topic and shorten the introduction.

2. The effect of wind on pollen dispersal in coastal zones is not fully discussed in this paper. Besides the Pinus, whether sea-land winds affect the dispersal of other pollen types? Palynological types of sediments at different depths indicate different vegetation types, are these related to wind propagation?

3. The description in lines 35-30 and lines 674-684 are puzzling. It is better if these conclusion could be described in plain language.

4. I have a question about pollen residues dating in coastal areas. Will a large amount of aquatic plant pollen interfere with the dating results? e.g. carbon reservoir from aquatic plant pollen?

5. No Hexagons were found in Figure2.

6. What is the size of the sieve for removing coarse and fine materials?

7. Figure6 is obscure, and the title can’t be read at present.

Author Response

Reviewer 2:

Thank you very much for your review and your useful comments and suggestions

The main topic of this paper is to evaluate the pollen representation for vegetation in coastal zones. However, too much complicated information is listed in the Introduction, which affects the reading, such as lines 87-111. It is recommended to focus on the topic and shorten the introduction.

Fluviomarine systems have a complex taphonomy. Furthermore, compared to other Quaternary sedimentary contexts, they also have certain particularities for establishing useful chronologies. We believe that there is little point in discussing the quality of pollen records to represent the vegetation of emerged areas and their changes (spatial and temporal), if the taphonomy and the chronological context of the sediment cannot be correctly interpreted/established. In this paragraph, some of the main limitations and potentialities of pollen records in fluviomarine contexts are summarized. We understand that this is a critical step, which must be prior to trying to determine whether pollen records in shallow seabed can describe the composition of the emerged vegetation.

The effect of wind on pollen dispersal in coastal zones is not fully discussed in this paper. Besides the Pinus, whether sea-land winds affect the dispersal of other pollen types? Palynological types of sediments at different depths indicate different vegetation types, are these related to wind propagation?

Models of the effect of wind in pollen dispersal has been largely studied during the las decades (Bunting and Middleton 2005; https://doi.org/10.1016/j.revpalbo.2004.12.009; Bunting et al. 2008; https://doi.org/10.1016/j.palaeo.2007.03.051; Lui et al. 2022; https://doi.org/10.1002/ecm.1513; Gaillard et al., 2024; DOI: 10.1007/s00334-008-0169-3). We assume that in coastal areas like Ría de Vigo the wind can affect the deposition of all types of anemophilous pollen. We have no evidence (e.g. independent data on winds affecting each aquatic system studied) that contradicts that this will occur in sediments deposited on the seabed, in coastal lagoon sediments or in upland pond sediments. In the latter, the accumulation of anemophilous pollen is inversely proportional to tree canopy around the pond [50]. But this type of argument does not make sense in the case of seabed samples. In the case of the Lagoa dos Nenos lagoon, it is in the outermost area of the estuary, e.g. more exposed to coastal winds. Certainly, it may also influence a lower rate of deposition of extra-local anemophilous pollen. This possibility is also considered in the discussion of the latest version of the manuscript.

The description in lines 35-30 and lines 674-684 are puzzling. It is better if these conclusion could be described in plain language.

Both paragraphs have been modified to try to clarify them.

I have a question about pollen residues dating in coastal areas. Will a large amount of aquatic plant pollen interfere with the dating results? e.g. carbon reservoir from aquatic plant pollen?

Risk of carbon reservoir effect from terrestrial material from Ría de Vigo is low because it is a predominantly granitic area, but some hot springs exist. Thus, in our basin evolution model we give more weight to the possibility of ancient material being reworked/rebedded during rainy/erosive periods than to a reservoir effect. Moreover, it is impossible to completely discard any carbon reservoir effect form aquatic plant material but dating pollen material has been proposed as one of the solutions proposed to date sediments potentially affected by reservoir effects (e.g. Vignoni et al. 2023, https://doi.org/10.5194/gchron-5-333-2023). With have incorporated a comment about this in the new version of the manuscript.

No Hexagons were found in Figure2.

Thank you, you are right. Pentagons, sorry. Table header has been modified accordingly.

What is the size of the sieve for removing coarse and fine materials?

250 μm and 10 μm, respectively.

Figure6 is obscure, and the title can’t be read at present.

Figures 6, 7 ,8 and 9 have been modified to be the titles more easily read.

Reviewer 3 Report

Comments and Suggestions for Authors

The manuscript entitled Capabilities and limitations of using fluviomarine pollen rec-2 ords to reconstruct spatiotemporal changes in coastal ecosys-3 tems during the Holocene: a case of study in Ría de Vigo (NW 4 Iberia) presents a study of surface pollen from a coastal area in NW Spain and compares the pollen assemblages with the modern vegetation types. Although the title and first part of the manuscript suggest that a Holocene multi-proxy record including pollen will be discussed with respect to the modern pollen assemblages, the study focuses on modern pollen samples from various sedimentary archives. I would suggest only focusing on the surface pollen data and changing the title and introduction of the manuscript accordingly. A brief comparison with the Holocene pollen record can be included in the discussion. This would make the manuscript shorter and more concise. In general, the result section could be more concise and shorter. The discussion needs to be rewritten as it currently reads as the result section. Results are presented here (again), but not properly discussed. The sentence structure in manuscript needs to be revised. I have included some suggestions.

To edit the manuscript, I converted the pdf into a word document. Unfortunately, the line numbers are placed throughout the text. The conversion has also changed the figures and tables, so I removed them from the word document entirely.

As this study presents new surface pollen data and represents an important contribution to the study of pollen-vegetation relationships, I recommend publication with major revision.

Please find below some minor questions and recommendations.

1. What is the Pinus subgenus Pinus pollen type? Should it be Pinus subg. haploxylon or Pinus subg. diploxylon?

2. Please format the reference list consistently.

3. Table 2: Change font to cursive for Fraxinus excelsior.

4. Replace Effluent with Outflow.

Comments for author File: Comments.pdf

Comments on the Quality of English Language

The English language needs some revision. There are issues with the syntax.

Author Response

Reviewer 3:

Thank you very much for your useful review of our manucript.

What is the Pinus subgenus Pinus pollen type? Should it be Pinus subg. haploxylon or Pinus subg. diploxylon?

[58] Moore, P.D., Webb, J.A., Collinson, M.E. Pollen Analysis, Second edition. Blackwell Scientific Publications 1991, Oxford, England.

Please format the reference list consistently.

Done, thank you for your remarks.

Table 2: Change font to cursive for Fraxinus excelsior.

Done, thank you.

Replace Effluent with Outflow.

Done, thank you

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

Author Response

Thank you very much for your remarks and comments

Reviewer 3 Report

Comments and Suggestions for Authors

The authors have adopted some suggestions. However, the title is still misleading as it does not reflect the actual subject matter, and the introduction still contains aspects that are not relevant to this pollen study. In general, the manuscript has not been shortened, and the text has not been revised to make it more concise and clearer as suggested. The result section still does not read well, it lacks consistency and clarity. The text needs proofreading, in particular English grammar and syntax. I have added some suggestions to the revised manuscript. Please review the reference list for format consistency.

Comments for author File: Comments.pdf

Comments on the Quality of English Language

The text needs proofreading, in particular English grammar and syntax.

Author Response

Thank you very much for your very detailed review and comments.

I don't know if I understood well why Reviewer 3 maintain that the title is still misleading as it does not reflect the actual subject matter. I would like to remind her/him that we have received an invitation from LAND to write an article for the special issue of your journal: "Pollen-Based Reconstruction of Holocene Land-Cover". We have centred our study in coastal areas, and particularly in the fluviomarine systems (rias) that are characteristic of the NW Iberia coasts. Fluviomarine systems have a complex taphonomy. Furthermore, compared to other Quaternary sedimentary contexts, they also have certain particularities for establishing useful chronologies and environmental interpretations. We believe that there is little point in discussing the quality of pollen records to represent the vegetation of emerged areas and their changes (spatial and temporal) if the taphonomy and the chronological context of the sediment cannot be correctly interpreted/established. In our introduction, some of the main limitations and potentialities of pollen records in fluviomarine contexts are summarized. The title of the manuscript also refers to that. We understand that this is a critical step, which must be prior to trying to determine whether pollen records in shallow seabed can describe the composition of the emerged vegetation. We therefore believe that the title is pertinent, as is the content and length of the introductory chapter. Certainly, the manuscript has not been substantially shortened. Some parts have been simplified or rearranged but, In fact, we have added a new section to the discussion at the request of one of the referees. Besides, in the second revision of referee 3 we were asked for new explanations for that section, which have been added in the latest version that we have sent to the journal. We believe that after comparing many data from different sedimentary context our results section might be complex but consistent. We have tried to improve all the issues related to English grammar and syntax indicated. Thank you again for your detailed review.