The Usability of Citizen Science Data for Research on Invasive Plant Species in Urban Cores and Fringes: A Hungarian Case Study

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

General Comments

The authors wrote a research article entitled "Usability of citizen science data for research on invasive plant species in urban cores and fringes: A Hungarian case study". The manuscript presents a comparative analysis of citizen science data (GBIF) and expert-collected data (LUCAS) for mapping invasive plant species in urban and suburban areas of Hungary. The study addresses an important gap in understanding the reliability and spatial biases of citizen science data, particularly for invasive species research. The topic is timely and relevant, given the increasing reliance on citizen science for biodiversity monitoring. Research scopes and quality fit journals (Land). However, the manuscript requires revisions to improve clarity, methodological rigor, and discussion of limitations before it can be considered for publication. I listed some minor comments in the specific comments below, and I recommend major revision.

 

Some detailed comments.

1. In the title, "A Hungarian case study"recommend changing it to "A case study in Hungarian"
2. Keywords, there are too many keywords. Irecommend condensing the most important keywords into five items..
3. The abstract section is too brief and should be supported by additional data from specific studies.The last sentence needs to mention your study's key points and significance for international reader. 
4. In the Introduction, For example, the transition from the introduction to the methods could be smoother. Consider adding a brief paragraph at the end of the introduction that outlines the study's objectives and hypotheses more explicitly.
5. In the Material and methods,The description of GBIF and LUCAS data collection processes is thorough, but the authors should clarify how data validation was performed for GBIF (e.g., the role of AI and community validation). The buffer zones (0-500 m, 500-1,000 m, 1,000-1,500 m) are justified, but the rationale for these specific distances could be better explained. Are these based on prior studies or ecological thresholds? The use of a generalized linear model (GLM) is appropriate, but the model specifications (e.g., link function, covariates) are not detailed. Include this information to ensure reproducibility.
6. In the Results, The results are presented clearly, but the tables (e.g., Table 2) could be more interpretable. Consider adding a column for "direction of bias" (over/underestimation) to summarize findings succinctly.
7. In the Discussions, The discussion effectively highlights the strengths and limitations of citizen science data but could be more critical of potential confounding factors.For example, how might volunteer behavior (e.g., preference for photogenic species like Elaeagnus angustifolia) bias the results? Could temporal mismatches between GBIF and LUCAS data collection periods affect comparisons? The conclusion that GBIF is suitable for "urbanophilic" species is well-supported, but the authors should acknowledge that this may not generalize to all regions or taxa. The policy implications (e.g., how to integrate citizen science into formal monitoring) could be expanded.
8. In the Conclusions, the conclusion section should include additional data to support the findings. Furthermore, the final sentence should outline the limitations of this study and suggest directions for future research.
9. In the References, The formatting of the references does not match the requirements of the journal (Land). It is recommended that the format be standardized according to the requirements of the journals (too old, and some of the references are not formatted in a uniform manner, such as the journal name is not italicized, the year is in the wrong position, and it is not bolded, etc.titles of journals).Please double-check the references.

 

All in all, I recommend major revisions before acceptance. The study has strong potential, but the current version requires refinement to meet the journal's standards. The manuscript provides valuable insights into the usability of citizen science data for invasive species research, particularly in urban settings. With revisions to address the above comments, it would make a significant contribution to the field.

Author Response

Response to Reviewer 1 Comments

 

Dear Reviewer 1,

 

thank you very much for evaluating our manuscript, and providing us the opportunity to submit again a revised version of the manuscript. We appreciate your positive and helpful comments.

 

We copied the reviewer comments below and marked our responses in red.

 

 

In the title, "A Hungarian case study"recommend changing it to "A case study in Hungarian"

We changed A “Hungarian case study” to "A case study in Hungarian" in the title.

 

 

1. Keywords, there are too many keywords. Irecommend condensing the most important keywords into five items..

 

We have reduced the number of keywords to five. The five keywords are: alien plants; crowd-sourced data; expert data; urban areas; urban fringe

 

 

2. The abstract section is too brief and should be supported by additional data from specific studies.The last sentence needs to mention your study's key points and significance for international reader. 

 

Thank you very much for your helpful comment. We have expanded the abstract based on your suggestions.

 

 

3. In the Introduction, For example, the transition from the introduction to the methods could be smoother. Consider adding a brief paragraph at the end of the introduction that outlines the study's objectives and hypotheses more explicitly.

 

Thank you very much for your comment. The following text has been added at the end of the introduction:

L: We provide insights into which invasive plant species, are preferentially recorded by volunteers working in and around urban areas. This is particularly relevant given that GBIF data are not collected within a defined sampling framework and lack a preplanned design. Building on the foundations of our research, data collected by volunteers can be validated through comparison with expert-generated datasets, thereby enabling an assessment of their suitability for scientific applications in studies concerning the occurrence of invasive plant species.

 

 

 

 

4. In the Material and methods,The description of GBIF and LUCAS data collection processes is thorough, but the authors should clarify how data validation was performed for GBIF (e.g., the role of AI and community validation). The buffer zones (0-500 m, 500-1,000 m, 1,000-1,500 m) are justified, but the rationale for these specific distances could be better explained. Are these based on prior studies or ecological thresholds? The use of a generalized linear model (GLM) is appropriate, but the model specifications (e.g., link function, covariates) are not detailed. Include this information to ensure reproducibility.

 

 

• The data were used without further validation after downloading. For validation, we relied on previous validation performed by the Pl@ntNet community and artificial intelligence. Please understand that we did not mention this after the last sentence of the „Citizen science-based data of the investigated plant species” section, the reason being that it was already mentioned in the text of the section above and we did not want to repeat ourselves.

 

The buffer zones are based on previous research and our own estimates. The following text has been inserted in the appropriate place: :L The radius of the buffer zone was determined based on previous research:

 

McKinney, M.L. Urbanization as a Major Cause of Biotic Homogenization. Biological Conservation 2006, 127, 247–260, doi:10.1016/j.biocon.2005.09.005.

 

Vakhlamova, T.; Rusterholz, H.P.; Kanibolotskaya, Y.; Baur, B. Changes in Plant Diversity along an Urban-Rural Gradient in an Expanding City in Kazakhstan, Western Siberia. Landscape and Urban Planning 2014, 132, 111–120, doi:10.1016/j.landurbplan.2014.08.014.

 

Wang, Z.; Yang, J. Urbanization Strengthens the Edge Effects on Species Diversity and Composition of Woody Plants in Remnant Forests. Forest Ecosystems 2022, 9, 100063, doi:10.1016/j.fecs.2022.100063)

 

• L 235-328: We inserted the following sentence: If the p-value < 0.05, the observed difference is considered statistically significant. The z-value provides information on both the direction (positive or negative) and the magnitude of the difference.

 

 

5. In the Results, The results are presented clearly, but the tables (e.g., Table 2) could be more interpretable. Consider adding a column for "direction of bias" (over/underestimation) to summarize findings succinctly.

 

We apologise for not inserting a column in the tables. This did not happen because we would not have been able to create a single column. For example, in Table 2, only for Robinia the GBIF data underestimated the occurrence count in all study areas, but for Solidago, the GBIF data overestimated in the urban core but underestimated in the buffers.

However, we admit that Table 2 made the results section too repetitive and for this reason we have moved Table 2 to the Appendix section.

 

 

6. In the Discussions, The discussion effectively highlights the strengths and limitations of citizen science data but could be more critical of potential confounding factors.For example, how might volunteer behavior (e.g., preference for photogenic species like Elaeagnus angustifolia) bias the results? Could temporal mismatches between GBIF and LUCAS data collection periods affect comparisons? The conclusion that GBIF is suitable for "urbanophilic" species is well-supported, but the authors should acknowledge that this may not generalize to all regions or taxa. The policy implications (e.g., how to integrate citizen science into formal monitoring) could be expanded.

 

Thank you very much for your helpful comment. We accept that the Discussion section was not well written in general, the section comparing with other results was almost missing. We extended the Discussion section with additional literature and compared our results with results from previous research. Please review the Discussion section.

 

 

7. In the Conclusions, the conclusion section should include additional data to support the findings. Furthermore, the final sentence should outline the limitations of this study and suggest directions for future research.

 

Thank you very much for your helpful comment. The Conclusion section has been extended based on the suggestions. Please review this section.

 

 

8. In the References, The formatting of the references does not match the requirements of the journal (Land). It is recommended that the format be standardized according to the requirements of the journals (too old, and some of the references are not formatted in a uniform manner, such as the journal name is not italicized, the year is in the wrong position, and it is not bolded, etc.titles of journals).Please double-check the references.

 

Thank you very much for your comment. We corrected the citations to the journal's standards. To prepare the citations, we used the Mendeley program and selected a citation style appropriate to the journal.

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

The manuscript entitled „Usability of citizen science data for research on invasive plant
species in urban cores and fringes: A Hungarian case study“ examines the usage of citizen science in for mapping the occurrence density of five invasive plant species. In the introduction section the authors gave an overview of the invasive species and citizen science in general, along with presenting the main research objectives that follow the aim of the manuscript. The materials and methods are clearley presented but the results section lacks  the importance of the study and its potential effects on practice, policy, or future research. However, here are some suggestions for the authors shown below as comments.

Comment 1: Within the abstract section, the names of plants should also be written italic

Comment 2: Lines 151-153- please explain physical properties that allow analysed plants to be recognised from landscape photographs with high efficiency by visual interpreta

Comment 3: Plant species studied in the research are currently the most aggressively spreading inva- sive species in Hungary... What is the basis for this claim?

Comment 4: Line 209- Solidago change to italic

Comment 5: Line 291-(Rae et al 2019) –change to [...]

Comment 6: Lines 273-274- ....“which have been pointed out by several previous authors“ (who are the authors?). The manuscript in general is lacking the results from other studies, current research in this research field, or general comparations of several authors that have published (if any) similar work.

Comment 7: The results section should give the main research findings along with providing informations about what are the main benefits or deficiency of the citizen science? What is the importance of the study and scientific contribution along with its potential effects on practice, policy, or future research.

Author Response

Response to Reviewer 2 Comments

 

Dear Reviewer 2,

 

thank you very much for evaluating our manuscript, and providing us the opportunity to submit again a revised version of the manuscript. We appreciate your positive and helpful comments.

 

We copied the reviewer comments below and marked our responses in red.

 

 

Comment 1: Within the abstract section, the names of plants should also be written italic

Thank you for noticing this mistake. We have corrected the species name in the abstract section to italic format.

 

Comment 2: Lines 151-153- please explain physical properties that allow analysed plants to be recognised from landscape photographs with high efficiency by visual interpreta

L 202-203 We have inserted the following sentence: Such physical characteristics include the pattern of the trunk, the color and shape of the leaves and flowers, and the appearance of the species in the landscape.

 

 

Comment 3: Plant species studied in the research are currently the most aggressively spreading inva- sive species in Hungary... What is the basis for this claim?

L 198-199 We have inserted the following sentence: These species are widely distributed across the country, occupying a broad range of habitat types and covering extensive areas.

 

Comment 4: Line 209- Solidago change to italic

L: 264 Thank you very much for your remark, the species name has been changed to italic format.

 

Comment 5: Line 291-(Rae et al 2019) –change to [...]

L 393 Thank you very much for your remark, we corrected the reference to the correct format for the journal.

 

Comment 6: Lines 273-274- ....“which have been pointed out by several previous authors“ (who are the authors?). The manuscript in general is lacking the results from other studies, current research in this research field, or general comparations of several authors that have published (if any) similar work.

L 364-366 Thank you for bringing this mistake to our attention. The sentence made no technical sense. Indeed, citizen science data have some weaknesses that make it not recommended for certain species (because it is difficult to recognise, for example), however, this weakness is not specific to the species listed above. For this reason, the second half of the sentence has been deleted. L 364-366

We absolutely agree with your comment. We have added additional references to the manuscript and compared our findings with previous results by other authors. Please refer to the discussion section.

 

Comment 7: The results section should give the main research findings along with providing informations about what are the main benefits or deficiency of the citizen science? What is the importance of the study and scientific contribution along with its potential effects on practice, policy, or future research.

Thank you very much for your supportive comment. The above-mentioned points have been included in the discussion section to complete this chapter.

Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

The manuscript deals with actual topic (using of Citizen Science in nature mapping is currently very popular). Invasive plants in urban areas are very common and mapping of its distribution offer interesting challenges in landscape research. I feel this manuscript has any potential for future publishing, but submitted form is very poor.

Firstly, there are some shortcomings in the main adea of the study as well as in methodology section: Line 102 etc: Better definition of scientific aims is needed (any definition of hypotheses in tested etc.). Line 108 - which cities exactly? Line 110-11: very poor description of many different conditions in fact.... I would appreciate if Authors should better explain what primary data were used. Or, only secondary data were used?

Secondly, presentation of results in Tables 2-5 is not very professional and some info are redundant and doubled. Presentation of results must be improved to the scientific brief form, the best should be any clear visualization of main findings of the study. 

Thirdly, thre is very poor (not acceptable) section Discussion (line 239-304). Section Discussion must be the longest section of the manuscript. Authors must discuss here very precisely all methods used in the paper as well as original findings with relevant up-to-date scientific literature published in Web of Science. Section Discussion must be divided at least to three subsections: discussion related to methods used, discussion related to original findings, discussion related to international importance of original findings for development of knowledge in the Landscape Ecology field. Section Discussion must be highly professional part of the paper.

Finally, section Introduction is very short and needs better insights to current knowldge-gaps in using Citizen Science (CS) approaches to invasive plants mapping world-wide. After it, one expect better insight to Hungary national context of using CS to mapping native and inveasive plants....  

Author Response

Response to Reviewer 3 Comments

 

Dear Reviewer 3,

 

thank you very much for evaluating our manuscript, and providing us the opportunity to submit again a revised version of the manuscript. We appreciate your positive and helpful comments.

 

We copied the reviewer comments below and marked our responses in red.

 

 

Firstly, there are some shortcomings in the main adea of the study as well as in methodology section: Line 102 etc: Better definition of scientific aims is needed (any definition of hypotheses in tested etc.). Line 108 - which cities exactly? Line 110-11: very poor description of many different conditions in fact.... I would appreciate if Authors should better explain what primary data were used. Or, only secondary data were used?

• The research questions have been clarified and a short paragraph inserted at the end of the Introduction. Please review these sections. (L: 118-127 and L: 132-138)
• L 159-164 We listed the names of the cities à (Békéscsaba, Budapest, Debrecen, Dunaújváros, Eger, Győr, Kaposvár, Kecskemét, Miskolc, Nyíregyháza, Pécs, Sopron, Szeged, Székesfehérvár, Szolnok, Szombathely, Tatabánya, Veszprém, Zalaegerszeg)
• 1. Study area section: This section has been expanded to include the following text: L: 146-154 The lowland regions of the Carpathian Basin are characterised by highly fertile chernozem soils being particularly dominant. The dominant land use type is arable land, while approximately 20% of the territory is forested areas. Black locust plantations, established primarily for their economic benefits, constitute a significant proportion of Hungary's total area, accounting for approximately 5%. The effects of climate change are increasingly manifesting in the form of more frequent extreme weather events and an elevated risk of summer droughts. Furthermore, biological invasions have caused significant degradation of natural and semi-natural habitats, with 13.1% of these areas currently invaded by alien species [2].
• The source and preparation content of the data was described in the description of the two databases, but it was not really mentioned whether these were primary or secondary data. Thank you for bringing this to our attention. We have filled this gap in the appropriate places. L 192-194 and 121-122 

 

 

Secondly, presentation of results in Tables 2-5 is not very professional and some info are redundant and doubled. Presentation of results must be improved to the scientific brief form, the best should be any clear visualization of main findings of the study. 

We apologise, but we did not consider it appropriate to use another form of visualisation. We consider that tables are necessary for the traceability of our studies. However, we admit that Table 2 made the results section too repetitive and for this reason we have moved Table 2 to the Appendix section.

 

 

Thirdly, thre is very poor (not acceptable) section Discussion (line 239-304). Section Discussion must be the longest section of the manuscript. Authors must discuss here very precisely all methods used in the paper as well as original findings with relevant up-to-date scientific literature published in Web of Science. Section Discussion must be divided at least to three subsections: discussion related to methods used, discussion related to original findings, discussion related to international importance of original findings for development of knowledge in the Landscape Ecology field. Section Discussion must be highly professional part of the paper.

Thank you very much for your helpful comment. We accept that the Discussion section was not well written in general, the section comparing with other results was almost missing. We extended the Discussion section with additional literature and compared our results with results from previous research. Please review the Discussion section.

 

 

Finally, section Introduction is very short and needs better insights to current knowldge-gaps in using Citizen Science (CS) approaches to invasive plants mapping world-wide. After it, one expect better insight to Hungary national context of using CS to mapping native and inveasive plants....  

• Thank you very much for your helpful suggestion. L 86- 98 We have added a paragraph to the Introduction section.
• Regarding the research on citizen science studies in Hungary, please allow us to mention only the research on invasive species, since this research is also focused on invasive species. Furthermore, we put this section in the discussion to make the introduction smoother.

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

I appreciate authors considering all of my comments and revising the manuscript accordingly, the revised version is significantly improved and I recommended it to be accepted with minor revisions for publication. 

The formatting of the references does not match the requirements of the journal (Land). It is recommended that the format be standardized according to the requirements of the journals (too old, and some of the references are not formatted in a uniform manner, such as the journal name is not italicized, the year is in the wrong position, and it is not bolded, etc.titles of journals). Please double-check the references.

Reviewer 3 Report

Comments and Suggestions for Authors

Dear Authors, thank you for improvement the manuscript following my comments to the sumbitted form. Now I agree with publishing of the study.