Short-Term Growth Dynamics of Spontaneous and Planted Vegetation on Subtropical Extensive Green Roof as Renaturalized Biotope

Response to Reviewer 1 Comments

Summary

Thank you very much for taking the time to review this manuscript. Please find the detailed responses below and the corresponding revisions/corrections highlighted/in track changes in the re-submitted files.

Point-by-point response to Comments and Suggestions for Authors

Comments 1: Rewrite lines 12-14 as follows: This perception is still deep-rooted among green space managers and the public worldwide, as they are generally uncertain on about the management need to allow these groups of flora to take root.

Response 1: Thank you, this sentence has been revised as suggested.

Comments 2: In line 14, replace community by communities.

Response 2: Thank you, this change has been made.

Comments 3: In line 16, insert an "a" between into and management.

Response 3: Thank you, the suggested edit has been implemented.

Comments 4: In lines 24-25, please move the words "During each quarterly survey" to the beginning of the sentence.

Response 4: Thank you, the sentence structure has been revised as requested.

Comments 5: In line 29, please correct the word fulfill.

Response 5: Thank you, the spelling error has been corrected.

Comments 6: In line 36, which compacted city?

Response 6: Thank you for pointing out, we revised “this compacted city” to “cities”

Comments 7: In line 63, do you mean Law et al. [9]?

Response 7: Yes, this reference has be corrected.

Comments 8: What gaps in knowledge would you like to address as the purpose of this paper? Presentation of technical research results may not be suitable to fill knowledge gaps in the field of your study. Please clearly address major challenges regarding the research topic and your novel contribution(s) to your field and in the context of your study.

Response 8: The introduction had been revised to more clearly articulate the knowledge gaps this study aims to address and the novel contributions of the research.

Comments 9: A diagram flow is desired to explain the method followed by the authors to develop the research.

Response 9: A methodology flowchart has been added to the revised manuscript.

Comments 10: The results obtained by the study should be compared to the available data noted in the literature review to highlight any new contribution of the work presented in the paper.

Response 10: The discussion section were expanded to include a more thorough comparison of the results to relevant prior studies.

Comments 11: How come the results presented in Table 1 are from more than 10 years ago?

Response 11: This data of this research was collected in 2014, and due to career change of first author and time management issue, the manuscript was not prepared in subsequent years. First author sees the novelty of this research and definitely contribute to new knowledge to this area of science, thus, it is worthwhile to publish this study and contribute although the dataset was collected 10 years ago. Recent published paper (https://doi.org/10.1016/j.nbsj.2023.100101) in 2024 also conducted experiment in 2014 and collected data for several years.

Comments 12: How did the authors determine the plant coverage? Nothing is mentioned about it.

Response 12: Author and trained personnels assessed plant coverage by visual estimation (for each plant species, coverage percentage on two 1x1m quadrats were estimated according to the Domin-Krajina cover-abundance scale, quadrat locations were determined by randomly generated grid numbers, the average figure was computed as the coverage percentage figure), details was supplemented in the revised manuscript.

Comments 13: How about the microbial diversity and activity in the health of plants, the increase in plant drought tolerance, nutrient availability, pathogen protection, and substrate stabilization?

Response 13: These additional factors related to plant and green roof health are indeed factors affecting plant growth and health, which could not be accounted in this paper, and they are mentioned as limitation of this study as future research directions.

Comments 14: Did the authors use some fertilizer in the green roofs?

Response 14: No fertilizer was used before and during the survey period, this information was clarified in the methodology section.

Comments 15: Conclusions section must be improved. The conclusions section should contain numbered short statements of major findings and new scientific results obtained by the author. A brief sentence for future research is also desired in the conclusions.

Response 15: The conclusions had been restructured to follow the suggested format, with clear and concise statements of the key findings and recommendations for future work.

Comments 16: Authors must include references of the current year 2024

Response 16: Thank you, references of 2024 were added.

Response to Reviewer 2 Comments

Summary

Thank you very much for taking the time to review this manuscript. Please find the detailed responses below and the corresponding revisions/corrections highlighted/in track changes in the re-submitted files.

Point-by-point response to Comments and Suggestions for Authors

Comments 1: The introduction effectively sets the stage for the study by highlighting the lack of research on spontaneous vegetation on green roofs. However, it would be beneficial to include a brief discussion on the specific ecological functions of these green roofs, such as their role in urban heat island mitigation or air quality improvement, to further contextualize the study's relevance.

Response 1: Thank you, this suggestion has been incorporated into the introduction section.

Comments 2: To enhance clarity, consider adding a schematic diagram of the green roof layout and the placement of different plant species.

Response 2: Thank you, a schematic diagram has been added to the methodology section to provide a visual representation of the green roof layout and plant species distribution.

Comments 3: It is mentioned that an auto sprinkler system was used for irrigation—clarifying the criteria for its operation (e.g., weather conditions that prompt irrigation) could provide better insights into the watering regime's influence on plant growth dynamics.

Response 3: Thank you, the irrigation regime have been clarified in the methodology section to better explain the watering regime and its potential impact on plant growth.

Comments 4: In the conclusion section, adding suggestions for future research directions, such as exploring different climatic zones or long-term impacts, would provide a useful perspective for ongoing research efforts.

Response 4: Thank you, the conclusion section has been updated to include suggestions for future research directions, I added that the different research perspectives and priorities which different parts of the world are looking at the issue, especially the sub-tropical / tropical zone.

Response to Reviewer 3 Comments

Summary

Thank you very much for taking the time to review this manuscript. Please find the detailed responses below and the corresponding revisions/corrections highlighted/in track changes in the re-submitted files.

Point-by-point response to Comments and Suggestions for Authors

Comments 1: The purpose of the study was too simple, and the scientific significance lacked.

Response 1: Thank you, the purpose of the study has been expanded to better highlight the scientific significance.

Comments 2: What is the current status and limitations of relevant research?

Response 2: A new section has been added to the introduction to provide an overview of the current status and limitations of relevant research.

Comments 3: What is the main greening species on roofs in Hong Kong, and the shortcomings of current greening species?

Response 3: The main greening species used on roofs in Hong Kong and the shortcomings of current species has been incorporated into the introduction.

Comments 4: Why choose the 15 species, and how is the representation of the species?

Response 4: The rationale for selecting the 15 species and their representativeness has been explained in the materials and methods section.

Comments 5: The part of 3.1 could remove to "2. Materials and Methods".

Response 5: The information from section 3.1 has been moved to the materials and methods section to improve the organization of the manuscript.

Comments 6: The discussion was too simple. What is difference and the reasons between this study and current studies?

Response 6: The discussion section has been expanded to highlight the key differences between this study and current research, as well as the underlying reasons for these differences.

Comments 7: The year for most references was too old.

Response 7: The reference list has been updated to include more recent studies in the field.

Response to Reviewer 4 Comments

Summary

Thank you very much for taking the time to review this manuscript. Please find the detailed responses below and the corresponding revisions/corrections highlighted/in track changes in the re-submitted files.

Point-by-point response to Comments and Suggestions for Authors

Comments 1: The research has a scientific novelty. However, it is desirable that the authors clearly state this in the paper.

Response 1: Thank you, this was clearly stated in the paper.

Comments 2: This study has theoretical and practical significance. This is a very important point. Unfortunately, the authors did not pay enough attention to it in the paper. It is desirable to correct this. It will make the paper more understandable and interesting.

Response 2: Thank you, this point was pinpointed in the text as suggested.

Comments 3: There are comments on the abstract. The abstract does not reflect the results, novelty and significance well. This needs to be improved.

Lines 18-26. I didn't understand. How did 7 plant species become 50 or 67 plant species? This piece of text needs to be edited properly. The reader could be confused and misled.

Response 3: Thank you, these issues in the abstract will be addressed and revised. The transplantation of native ferns and forbs was carried out over 16 months, part of original planted vegetation were removed when transplanting took place, bare soil was exposed, thus colonization of plants took place. Those 50+ Spontaneous plants colonized on the green roof was recorded one month after the last phase of transplanting. Relevant part in abstract had been revised and edited.

Comments 4: In the introduction, the relevance of the study is well substantiated is described. The aims of the study should be described in more detail. Also in this section, you should update the reader on the research methods you will use to achieve your aim.. The description of the current state of the problem can be improved. The current version of the paper has regional specifics. It is necessary to reconsider the formulation of the task and the understanding of the results so that the paper becomes more interesting to readers from other countries, not just from China. It is necessary to put the necessary accents.

Response 4: Thank you, the introduction will be revised to address these points and make the paper more accessible to an international audience, at least this research had shed light on green roof and amenity lawn in wider tropical and sub-tropical regions.

Comments 5: The methodology approaches are described in detail. The authors used methods adequate to the tasks set. Adequately selected methods allow us to consider the conclusions justified. It would be more logical to move section 3.1 (Vegetation surveys and statistical analysis) to the section on the methodology.

Response 5: Thank you, the methodology section was reorganized as suggested.

Comments 6: The results are presented clearly and clearly. Figures and tables are informative. Visualisation of results is acceptable. I can advise the authors to carry out an analysis of the species abundance distribution. You can find information about this in the paper "Species abundance distributions: investigation of adaptation mechanisms of plant communities". This method gives excellent results and will significantly strengthen the paper.

Response 6: Thank you for the suggestion, conducting the species abundance distribution analysis is an excellent idea, we adapted Figure 7b and 8b showing species abundance distribution with linear regression functions. This is the best illustrating the general trend of temporal changes of species abundance throughout the year.

Comments 7: The current version of the discussion should be improved. The Discussion section is an important part of the paper. It is here that the authors should determine the place of their research in world science, compare the results obtained with those of other studies, including those carried out in other countries and climatic zones, explain the strengths of the approaches used, the novelty, the practical and theoretical significance of the results in comparison with other studies.

Response 7: Thank you, the discussion section had been thoroughly revised to address these points and provide a more comprehensive and impactful discussion of the research.

Comments 8: Conclusions follow from the results and are reasonable. However, the conclusions should also be improved so that they are more interesting to readers from other countries. Despite the fact that English is not my native language, I read the paper with interest and had no difficulties in understanding.

Response 8: Thank you, the conclusions will be revised to be more accessible and appealing to an international audience.