Epiphytic Habit and Spatial Distribution Patterns of Phalaenopsis deliciosa and Phalaenopsis hainanensis

Response to Reviewer X Comments

1. Summary

First of all, we would like to express our heartfelt and deep gratitude to you for taking the time, in your very busy schedule, to carefully and meticulously review our manuscript. Your detailed comments, especially on formatting, citation style, and other formal issues, clearly show your high standards and strong sense of responsibility as a reviewer. We truly feel honored that our work has received such careful attention and rigorous evaluation.

After reading your comments, we fully realized that our initial submission contained many avoidable mistakes in formatting and references, which fell short of the standards expected by the journal and by the academic community. This is entirely due to our lack of sufficient care and strict self-checking before submission. Your comments not only pointed out specific problems in the manuscript, but also reminded us, in a very profound way, of the importance of rigor and precision in academic writing. For this, we are sincerely grateful.

In accordance with your suggestions, we have carefully revised the manuscript line by line. All the changes made specifically in response to your comments have been clearly marked in green in the revised manuscript, so that you can easily identify and check them. In addition, the text shown in red corresponds to modifications made in response to comments from other reviewers. We would be very grateful if you could kindly also look over these changes.

We sincerely appreciate the time and effort you have devoted to identifying the errors and inconsistencies in our manuscript. At the same time, we are deeply aware that our insufficiently careful work has unnecessarily increased your workload. For this, we feel truly ashamed and deeply sorry. We offer our most sincere apologies for any inconvenience and extra burden that our lack of meticulousness in formatting and referencing has caused you.

This review process has been a valuable lesson for us. We have re-examined our internal checking procedures and will strengthen our pre-submission proofreading and cross-checking of all references, citations, and formatting details. We are determined to avoid similar problems in future submissions, so as not to waste the valuable time of editors and reviewers again.

Once again, we would like to express our heartfelt thanks for your time, patience, and valuable guidance. Your careful review and constructive comments have significantly improved the quality, clarity, and professionalism of our manuscript. We are sincerely grateful for your help.

In addition, regarding your important concern about whether the conclusions of our study were sufficiently supported by the results, we have taken this issue very seriously and conducted a comprehensive strengthening of the analytical framework, methodological rigor, and ecological interpretation throughout the manuscript. Following your guidance, we implemented substantial improvements to ensure that every conclusion is now explicitly supported by transparent quantitative evidence and clearly articulated methodological justification.

First, we revised the title according to your suggestion so that it more accurately reflects the community ecology component and the integrative scope of the study. Second, we substantially enhanced the community ecology methodology by incorporating essential quantitative indices, including Shannon, Simpson, and Pielou diversity indices; sampling completeness (coverage); species-accumulation–based assessments; standardized explanations of sampling constraints; clearer descriptions of importance values and host selectivity indices; and a detailed botanical areal-type framework following Zhengyi Wu (2011). These additions ensure that our ecological interpretations now have solid quantitative and methodological support.

Third, in response to your concerns about sampling limitations, we added explicit clarification that Phalaenopsis hainanensis is an extremely small population species (PSESP) restricted to steep river valleys and fragmented limestone slopes within the Hainan Tropical Rainforest National Park, where access is strictly regulated. Therefore, the sampling plots in our study reflect the maximum feasible legal and safe sampling effort, rather than methodological bias. We sincerely apologize that these essential constraints were not made sufficiently clear in our initial submission, which may have led to confusion during review.

Fourth, we strengthened the ecological interpretation of host selectivity, spatial patterns, and community structure by avoiding direct comparisons influenced by unequal sampling areas, clarifying that “41 vs. 17 hosts” refers only to within-plot recorded trees, and replacing speculative statements with explanations grounded in established orchid ecology—such as seed dispersal limitation, mycorrhizal recruitment constraints, and microhabitat patchiness.

Fifth, to improve transparency, we expanded Appendix B with detailed formulas and step-by-step calculation methods for vertical projection, importance values, and host tree measurements, and we clarified the rationale for spatial analysis threshold decisions with references to recent forestry modelling literature (Bončina 2022; Bončina 2025; Nanos 2017).

Lastly, we strengthened the conservation implications by situating our findings within the broader ecological context of epiphytic orchids and by emphasizing the urgent conservation significance of P. hainanensis, a species with an extremely small wild population on Hainan Island.

We sincerely apologize for the additional workload caused by the lack of clarity in our initial submission, especially considering the ecological complexity and strict sampling restrictions associated with protected tropical rainforest environments. Your thoughtful insights have greatly improved the scientific rigor of our work and guided us toward higher standards in research and reporting.

Yours sincerely,

All authors

2. Questions for General Evaluation

Reviewer’s Evaluation

Response and Revisions

Does the introduction provide sufficient background and include all relevant references?

Yes

Are all the cited references relevant to the research?

Yes

Is the research design appropriate?

Yes

Are the methods adequately described?

Yes

Are the results clearly presented?

Can be improved

First, we revised the title according to your suggestion so that it more accurately reflects the community ecology component and the integrative scope of the study. Second, we substantially enhanced the community ecology methodology by incorporating essential quantitative indices, including Shannon, Simpson, and Pielou diversity indices; sampling completeness (coverage); species-accumulation–based assessments; standardized explanations of sampling constraints; clearer descriptions of importance values and host selectivity indices; and a detailed botanical areal-type framework following Zhengyi Wu (2011). These additions ensure that our ecological interpretations now have solid quantitative and methodological support.

Third, in response to your concerns about sampling limitations, we added explicit clarification that Phalaenopsis hainanensis is an extremely small population species (PSESP) restricted to steep river valleys and fragmented limestone slopes within the Hainan Tropical Rainforest National Park, where access is strictly regulated. Therefore, the sampling plots in our study reflect the maximum feasible legal and safe sampling effort, rather than methodological bias. We sincerely apologize that these essential constraints were not made sufficiently clear in our initial submission, which may have led to confusion during review.

Fourth, we strengthened the ecological interpretation of host selectivity, spatial patterns, and community structure by avoiding direct comparisons influenced by unequal sampling areas, clarifying that “41 vs. 17 hosts” refers only to within-plot recorded trees, and replacing speculative statements with explanations grounded in established orchid ecology—such as seed dispersal limitation, mycorrhizal recruitment constraints, and microhabitat patchiness.

Fifth, to improve transparency, we expanded Appendix B with detailed formulas and step-by-step calculation methods for vertical projection, importance values, and host tree measurements, and we clarified the rationale for spatial analysis threshold decisions with references to recent forestry modelling literature (Bončina 2022; Bončina 2025; Nanos 2017).

Lastly, we strengthened the conservation implications by situating our findings within the broader ecological context of epiphytic orchids and by emphasizing the urgent conservation significance of P. hainanensis, a species with an extremely small wild population on Hainan Island.

Are the conclusions supported by the results?

Yes

3. Additional clarifications

We would also like to sincerely report to you that we have carefully corrected every mistake that you patiently identified in your review. Each of the issues you pointed out has been meticulously revised in the manuscript, and the corresponding corrections have been clearly marked to ensure full transparency. Beyond addressing the specific points you mentioned, we have also conducted a comprehensive re-examination of the entire manuscript, line by line, to identify and amend any additional oversights that may have resulted from our previous lack of thoroughness.

We deeply regret that our insufficiently careful initial submission caused unnecessary inconvenience and added to your workload. For these avoidable errors and for the time they required you to spend, we offer our most sincere and heartfelt apologies. Your effort in reviewing our work—despite these shortcomings—means a great deal to us. We are truly grateful for your patience, your meticulous attention, and your willingness to guide us toward a more rigorous and responsible academic standard. Thank you sincerely for giving us this valuable opportunity to correct our mistakes and learn from them.

Response to Reviewer X Comments

1. Summary

On behalf of all authors, we would like to express our sincere gratitude for your thorough, constructive, and insightful review. Your comments were exceptionally valuable and helped us substantially improve the scientific rigor, clarity, and ecological relevance of our manuscript. We deeply appreciate the time and expertise you dedicated to evaluating our work.

Over the past several days, our team has held multiple detailed internal discussions and cross-checked the manuscript carefully against your comments. Through this revision process, we have gained deeper understanding not only of community ecology analytical standards, but also of methodological rigor, clarity of ecological interpretation, and the importance of transparent sampling limitations. This has been a truly rewarding learning opportunity for all of us.

Summary of Major Revisions Made in Response to Your Comments

Following your guidance, we have made comprehensive improvements across the manuscript:

1. Title Revision

We adopted the reviewer’s suggested title to better reflect the community ecology component and the integrative scope of the study.

2. Community Ecology Methods Added

We have now added:

Shannon, Simpson, and Pielou diversity indices

Sampling completeness (coverage)

Species-accumulation–based assessments

Standardized statements explaining sampling constraints

Clarifications about importance values and host selectivity indices

Detailed botanical areal-type methodology per Zhengyi Wu (2011)

3. Clarification of Sampling Limitations

We explicitly explain that:

Phalaenopsis hainanensis is an extremely small population species (PSESP) on Hainan Island

Many areas of its distribution fall within Hainan Tropical Rainforest National Park, where access is strictly restricted

Forest terrain is dominated by steep river valleys and fragmented limestone slopes

Therefore, all quadrats represent the maximum feasible legal and safe sampling area, not methodological bias

We sincerely apologize that these constraints were not clearly communicated in the initial submission, which may have caused unnecessary difficulty during review.

4. Host Selectivity, Spatial Pattern, and Community Descriptions

We have:

Avoided direct comparisons affected by unequal sampling area

Clarified that “41 vs. 17 hosts” reflects only within-plot records

Added biological reasoning supported by the literature, not speculation

Strengthened the context with known orchid ecology patterns (seed dispersal limits, mycorrhizal recruitment constraints, microhabitat patchiness)

5. Vertical Projection, Importance Values, and Host Tree Calculations

Added detailed calculation methods in Appendix B

Provided statistical context for community importance measures

Clarified criteria used for spatial analysis threshold decisions, with support from recent forestry modelling literature (Bončina 2022; Bončina 2025; Nanos 2017)

6. Conservation Implications

We enhanced this section by integrating broader epiphytic orchid ecology perspectives and highlighted the urgent conservation importance of P. hainanensis—a species with extremely small wild population on Hainan Island.

Closing Remarks

We sincerely apologize for the additional workload caused by our initial lack of clarity, especially given the ecological complexities and sampling restrictions in protected tropical rainforests. Your thorough review has not only improved the manuscript significantly but has also guided us toward better research standards.

If future conservation policies permit expanded field access, we fully intend to conduct a comprehensive, large-scale ecological survey of both Phalaenopsis deliciosa and P. hainanensis. We hope to contribute an even more refined and integrative study to Diversity, and we would be honored to receive your expert guidance again.

Thank you once more for your thoughtful, patient, and highly constructive review. We truly appreciate your efforts and the valuable time you have invested in our work.

2. Questions for General Evaluation

Reviewer’s Evaluation

Response and Revisions

Does the introduction provide sufficient background and include all relevant references?

Can be improved

We sincerely thank the reviewer for the thoughtful evaluation of our Introduction section. We fully agree that the background information and literature coverage required improvement in the original submission. In response, we carefully revised and expanded the Introduction to provide a more thorough, well-contextualized foundation for the study.

Specifically, we:

(1) Strengthened the ecological background by integrating additional references on epiphytic orchids, their environmental drivers, and host-tree interactions (Revised manuscript: Page 7, Lines 149–161; Page 7, Lines 172–173; Page 8, Lines 174–176).

(2) Clarified seed dispersal limitations, microhabitat filters, and fungal dependence with updated and verified citations, ensuring that the discussion aligns with established orchid ecology literature.

(3) Improved conceptual grounding by linking our research questions to prior studies and highlighting ecological patterns relevant to epiphytic community assembly.

(4) Refined ambiguous statements, added quantitative floristic evidence, and corrected incomplete or misleading citations pointed out by the reviewer.

Together, these revisions substantially enhance the scientific depth, relevance, and clarity of the Introduction. We sincerely appreciate the reviewer’s guidance, which significantly improved the rigor and completeness of this section.

Are all the cited references relevant to the research?

Yes

We sincerely thank the reviewer for confirming that all cited references are relevant to the research. We carefully re‐checked the reference list during revision and ensured that every citation directly supports the methodological framework, ecological context, or interpretation of results. No further changes were required for this section, but we remain grateful for the reviewer’s positive evaluation.

Is the research design appropriate?

Must be improved

We sincerely thank the reviewer for evaluating the research design and agree that improvements were necessary. After re-examining the study framework, we recognized that several methodological constraints—especially those related to unequal accessibility of natural populations, heterogeneous terrain, and strict protection regulations within Hainan Tropical Rainforest National Park—were not sufficiently articulated in the original submission. These constraints directly influenced plot selection, sampling area, and the number of available individuals, which may have affected the overall robustness of the design.

To address this, we have substantially expanded the methodological descriptions to provide clearer justification for the sampling framework. Specifically, we have:

(1) Clarified the objective criteria for selecting accessible populations, noting that Phalaenopsis hainanensis is an extremely small population species and that only legally accessible confirmed populations could be surveyed;

(2) Explained why transects and quadrats of different sizes were necessary, given steep river valleys and fragmented limestone terrain, and emphasized that no direct comparisons were made between sampling units of different sizes;

(3) Added diversity indices (Shannon–Wiener, Simpson) and coverage estimators calculated separately for each species, to characterize their respective communities without implying standardized comparisons;

(4) Inserted explicit statements indicating that unequal sampling areas prevented direct cross-species comparisons, and that all results are interpreted descriptively within each species’ habitat;

(5) Committed to conducting more balanced and comprehensive sampling once conservation regulations allow broader access, and to publishing improved work in Diversity in the future.

We respectfully hope that these revisions strengthen the transparency, rigor, and interpretability of the research design. We sincerely appreciate the reviewer’s constructive guidance, which has greatly improved the overall quality of the manuscript.

Are the methods adequately described?

Must be improved

We wholeheartedly thank the reviewer for this important evaluation. We agree that the original Methods section lacked sufficient detail. In response, we have substantially expanded methodological descriptions by:

1.Clarifying plot selection criteria and the access limitations imposed by the national park.

2.Adding Appendix B with a detailed procedure for vertical projection measurements of epiphytes.

3.Refining definitions of relative abundance, frequency, prominence, and importance values (IM), explaining their descriptive nature.

4.Stating that host-selectivity indices (Esi) were not subjected to inferential statistical testing and explaining the reasons.

5.Providing complete species nomenclature in Appendix A with full author citations, and indicating the taxonomic reference database used.

6.Adding diversity indices (Shannon, Simpson, coverage) calculated independently for each habitat.

These improvements greatly enhance reproducibility, analytical clarity, and methodological transparency. We are sincerely grateful for the reviewer’s guidance, which has significantly strengthened this section.

Are the results clearly presented?

Can be improved

We thank the reviewer for the suggestion. To improve clarity:

We revised wording to avoid unintended comparisons between species.

We explicitly stated that host species numbers (e.g., 41 vs. 17) represent within-plot records only.

Diversity values were presented descriptively, not inferentially.

Spatial pattern scales were specified with P-values.

Biogeographical Shannon indices were added to quantify patterns.

Are the conclusions supported by the results?

Must be improved

We sincerely thank the reviewer and fully agree that the conclusions required clearer emphasis and stronger linkage to the results. The revised conclusions now:

1.Summarize the major findings explicitly, including community composition, host preferences, biogeographical structure, and spatial aggregation.

2.Highlight the ecological and conservation implications, particularly for the extremely small population size of P. hainanensis.

3.Acknowledge methodological constraints and avoid any cross-species quantitative inference.

4.State commitments for future research once access restrictions are relaxed.

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

Comments 1: Sampling design: The description of the sampling design, as currently presented, is not sufficiently detailed. To ensure the reproducibility of the study, it is necessary to clearly specify the methodology used to select the sampling plots. Which objective criteria were applied for their selection? Were the plots randomly chosen in the field? Were there specific thresholds or parameters guiding their choice? I recommend providing a clearer explanation of the selection criteria and specifying the total number of areas surveyed.

In general, the dimensions of the sampling plots should be comparable; however, in this study, two different plot types were used (quadrats and transects) with considerably different sizes. This may introduce sampling bias, leading to non-comparable datasets and potentially distorted results. Comparisons should necessarily be made using areas of equivalent size. Heterogeneous sampling units do not allow for an adequate assessment of all environmental covariates influencing the data and may therefore act as confounding factors. This issue could affect the reliability and significance of all reported results.

Response 1: We sincerely thank the reviewer for this important and constructive comment. We fully agree that the original description of the sampling design lacked sufficient detail, and we have carefully revised the manuscript to address all concerns. Below, we summarize the specific modifications made in direct response to your suggestions:

(1) Clear explanation of objective criteria for selecting sampling plots

To ensure transparency, we added explicit information indicating that Phalaenopsis hainanensis is an extremely small population species, with very limited and fragmented natural populations. The strict access regulations of Hainan Tropical Rainforest National Park further restrict where scientific investigation can legally occur. Therefore, plots were selected exclusively in verified, accessible wild populations, rather than randomly. This clarification directly addresses the reviewer’s question regarding objective selection criteria.

(2) Explanation of unequal plot sizes and how comparability was addressed

We fully agree that differences in sampling area can introduce bias. To avoid inappropriate cross-species comparisons, we did not use raw species richness for interpretation. Instead, we added calculations of Shannon–Wiener and Simpson diversity indices for each orchid’s habitat independently, allowing community structure to be described without relying on unequal sampling areas. This directly responds to the concern regarding non-comparable plot dimensions.

(3) Supplementation of total surveyed areas and full sampling framework

We clarified the total number of survey areas and reorganized this part of the Methods to improve completeness of the sampling framework.

At the same time, we removed the unnecessary explanation of why both transects and quadrats were used, as suggested, ensuring a clearer and more concise methodological description.

(4) Revision of the manuscript title to reflect community‐ecology relevance

Following reviewer comments (and those of another reviewer), we updated the title to:

“Epiphytic habits, community attributes, and spatial distribution patterns of Phalaenopsis deliciosa and Phalaenopsis hainanensis on Hainan Island.”

This change helps emphasize the relevance of community attributes and clarifies how the sampling design relates to the study’s scope.

Strengthening of the Manuscript

Together, these revisions substantially improve the manuscript by:

Ⅰ Providing a transparent, repeatable sampling rationale rooted in conservation and logistical realities;

Ⅱ Preventing misinterpretation caused by heterogeneous sampling areas;

Ⅲ Incorporating standardized diversity indices rather than raw species counts;

Ⅳ Presenting a more coherent and ecologically grounded research framework;

Ⅴ Enhancing the overall methodological rigor and clarity of the study.

We sincerely appreciate the reviewer’s detailed and thoughtful guidance, which has significantly strengthened the scientific quality and reproducibility of our work.

Comments 2: Line 106: The distribution of the plots is not clear in the image, and the environmental conditions are not well visible. Which matrix was used to identify the areas? Are the plots comparable in terms of edaphic, climatic, topographic conditions, and anthropogenic impact? Please specify this in the text and in the figure caption.

Response 2: We sincerely thank the reviewer for this extremely important and insightful comment. We completely agree with your evaluation, and we deeply apologize that our initial description did not clearly explain the objective constraints and methodological rationale underlying the sampling design.

First, regarding your concern about the use of two different plot types (quadrats and transects) with substantially different sizes: we fully acknowledge that such heterogeneity would normally introduce sampling bias. We apologize for not providing sufficient explanation earlier. In our study, this inconsistency was not the result of methodological preference, but of unavoidable geographic and conservation constraints. Phalaenopsis hainanensis is an extremely small population species, and its remaining wild individuals occur only in a few steep river valleys and fragmented limestone slopes within the Hainan Tropical Rainforest National Park. Many surrounding areas fall inside strictly protected zones where scientific access is prohibited.

Because of these limitations, we were only able to establish plots in terrain that was legally accessible and physically safe. In some areas, the slope conditions allowed only narrow transects; in others, limited flat space enabled the placement of quadrats. We truly regret that we did not explain these constraints clearly in the first submission.

Second, we fully agree with the reviewer that comparisons must be made using equal sampling areas. Out of respect for scientific rigor, we have revised the manuscript to avoid any cross-species comparisons based on raw counts, and we now present all community attributes strictly within each species’ habitat. To characterize diversity without introducing area-based bias, we calculated Shannon and Simpson indices for each orchid’s habitat independently. These indices provide comparable measures of internal community structure without assuming equivalence in sampling extent.

Third, we understand the reviewer’s concern about the need for a clearly defined sampling frame. Accordingly, we have added detailed explanations of plot-selection constraints in the Methods section and clarified the total number of accessible survey areas. At the same time, we have removed unnecessary statements about why both transects and quadrats had to be used, ensuring that the revised manuscript is clearer, more transparent, and more scientifically cautious.

Finally—and most importantly—we sincerely apologize for the limitations caused by the protected-area policies. Once future conservation regulations allow broader access, we fully commit to conducting a more complete and standardized survey, with equal-area sampling units and improved ecological analyses. It would be our honour to submit such expanded work to Diversity and humbly invite your expert review again. Your comments have been invaluable in guiding our current revision and will continue to shape our future fieldwork and analytical framework.

We deeply appreciate your time, expertise, and patience. Thank you again for helping us significantly improve our manuscript.

Comments 3: The discussion section lacks sufficient references to the extensive existing literature on epiphytic orchids and the role of environmental factors and host trees. This is important, as the study should interpret and contextualize its results by comparing them with previous research, identifying key ecological similarities and differences. Strengthening this section would significantly enhance the scientific relevance and interpretative depth of the paper.

Response 3: We sincerely thank the reviewer for this insightful and important recommendation. We fully agree that strengthening the discussion by integrating a broader body of literature on epiphytic orchids—particularly regarding environmental determinants and host-tree influences—is essential for enhancing the ecological interpretation of our findings. In response, we have substantially revised and expanded the discussion section.

Specifically, on page 7 (Lines 149–161 and 172–173) and page 8 (Lines 174–176) of the revised manuscript, we have incorporated multiple additional references that document (i) the ecological mechanisms shaping epiphytic orchid distribution, (ii) the roles of microclimate, bark microhabitat heterogeneity, and host functional traits, and (iii) the interactions between seed dispersal constraints, mycorrhizal dependence, and host-tree architecture. These additions directly connect our results to well-established patterns reported in previous studies, thereby strengthening the scientific relevance, contextual depth, and interpretative rigor of the manuscript.

Comments 4: The conclusions should give greater emphasis to the main findings obtained in this study, summarizing the key outcomes and highlighting the specific scientific contribution within the broader ecological and conservation context.

Response 4: We sincerely thank the reviewer for the valuable and insightful comments. We fully agree with the reviewer’s concerns regarding the interpretation of monotypic families and genera, the presentation of host-species numbers, the need for clarification of analytical limitations, and the necessity of providing quantitative support in the biogeographical analysis. In response, we have made substantial revisions to improve scientific transparency, avoid any unintended inferential implications, and strengthen the methodological rigor of the manuscript. Specifically, we revised the descriptions of monotypic families and genera to clearly state that these values serve purely as descriptive indicators of the surveyed flora, without implying statistical deviation from random expectations. Corresponding updates are now included in Page 7, Lines 214–216. In addition, we clarified that the reported host-species numbers (e.g., 41 vs. 17) represent within-plot observations only, and are not intended—and cannot be used—as interspecific comparisons due to unequal sampling areas and strict park-access limitations. This clarification, along with the addition of host-community Shannon and Simpson diversity indices and sampling-coverage estimates for each species, has been incorporated into Page 1, Lines 16–20. We also revised the discussion of dominant families to emphasize that these are descriptive components of each orchid’s habitat, and not statistical contrasts between communities. This revision enhances neutrality and avoids any over-interpretation (Page 7, Lines 217–221). Following the reviewer’s recommendation, we further strengthened the biogeographical analysis by calculating Shannon diversity indices for the areal-type composition of both orchid communities (H′ = 1.818 for P. deliciosa; H′ = 1.985 for P. hainanensis), and integrated these values into Pages 10–11, Lines 296–297. Finally, we revised the text to clarify that the epiphytic selectivity index (Esi) was used descriptively, without null-model testing, due to limitations in quantifying unbiased host availability within restricted, steep, and fragmented survey areas; this clarification has been incorporated into the revised manuscript.

These revisions directly address the reviewer’s concerns and greatly enhance the clarity, scientific rigor, and interpretative accuracy of the manuscript. We are sincerely grateful to the reviewer for the constructive feedback, which significantly improved the quality and transparency of our work.

Comments 5: It is important to clearly state the taxonomic framework adopted and to report all species names in their full form, including genus, specific epithet, and author citation. I recommend including in the Supplementary Materials a table listing all species with complete nomenclature, and referring to this table in the Materials and Methods section. The adopted nomenclatural reference (e.g., following POWO [https://powo.science.kew.org/] or World Flora Online [https://www.worldfloraonline.org/]) should also be explicitly indicated.

Response 5: We sincerely thank the reviewer for raising this important point regarding the clarity and completeness of our taxonomic framework. We fully agree with your recommendation and appreciate the opportunity to improve the nomenclatural transparency of our manuscript. As suggested, we have now ensured that all species names are reported in their full scientific form, including genus, specific epithet, and author citation.

To address this comment thoroughly, we have added a detailed species list to the Supplementary Materials. Specifically, Appendix A now contains Annexed Table 1: The species list of the Phalaenopsis deliciosa community and Annexed Table 2: The species list of the Phalaenopsis hainanensis community, both of which provide complete nomenclatural information for all recorded species. These tables list the full Latin names, including the author citations, exactly as recommended by the reviewer.

We sincerely appreciate the reviewer’s constructive suggestion, which significantly strengthens the taxonomic rigor and reproducibility of our work.

4. Additional clarifications

We sincerely thank the reviewer for the careful and insightful evaluation of our manuscript. Below we provide additional clarifications to further enhance the transparency, reproducibility, and scholarly rigor of the study.

1. Taxonomic framework and full species nomenclature

In accordance with the reviewer’s recommendation, we confirm that all species names—including genus, specific epithet, and author citation—are fully reported in the Supplementary Materials. These complete nomenclatural entries are provided in Appendix A, specifically in:

Annexed Table 1: The species list of the Phalaenopsis deliciosa community

Annexed Table 2: The species list of the Phalaenopsis hainanensis community

Both tables include the full scientific names following current global taxonomic standards. Additionally, we have explicitly stated in the revised manuscript that our nomenclatural reference follows Plants of the World Online (POWO) and is cross-checked with World Flora Online (WFO) to ensure accuracy and consistency.

2. Methodological clarifications added throughout the manuscript

As detailed in our responses, we have incorporated multiple revisions to strengthen methodological transparency, including:

clear justification of plot selection under strict conservation constraints,

explicit distinction between descriptive and inferential analyses,

addition of Shannon & Simpson diversity indices and sampling coverage estimates,

clarification that host-species counts reflect within-plot observations only,

detailed explanation of the vertical projection method in Appendix B,

explanatory notes stating that epiphytic selectivity (Esi) values are descriptive and not subjected to null-model statistical testing.

3. Strengthened discussion with additional references

Following reviewer suggestions, we have expanded the Discussion to better contextualize our findings within the broader literature on epiphytic orchid ecology, microhabitat filtering, host-tree characteristics, and fungal-mediated recruitment. This includes the incorporation of updated and field-relevant references, now cited in Sections Page 7, Lines 149–161, 172–173; Page 8, Lines 174–176.

4. Clarification of conclusions

We have revised the Conclusion section to more clearly emphasize the novel contributions of this study—particularly regarding community attributes, host selectivity patterns, and spatial distribution characteristics of two rare Phalaenopsis species in highly restricted habitats.

We sincerely apologize for the additional workload caused by our initial lack of clarity, especially given the ecological complexities and sampling restrictions in protected tropical rainforests. Your thorough review has not only improved the manuscript significantly but has also guided us toward better research standards.

If future conservation policies permit expanded field access, we fully intend to conduct a comprehensive, large-scale ecological survey of both P. deliciosa and P. hainanensis. We hope to contribute an even more refined and integrative study to Diversity, and we would be honored to receive your expert guidance again.

Thank you once more for your thoughtful, patient, and highly constructive review. We truly appreciate your efforts and the valuable time you have invested in our work.

With our highest respect and gratitude

All authors

19 November 2025

Response to Reviewer X Comments

1. Summary

On behalf of all authors, we would like to express our sincere gratitude for your thorough, constructive, and insightful review. Your comments were exceptionally valuable and helped us substantially improve the scientific rigor, clarity, and ecological relevance of our manuscript. We deeply appreciate the time and expertise you dedicated to evaluating our work.

Over the past several days, our team has held multiple detailed internal discussions and cross-checked the manuscript carefully against your comments. Through this revision process, we have gained deeper understanding not only of community ecology analytical standards, but also of methodological rigor, clarity of ecological interpretation, and the importance of transparent sampling limitations. This has been a truly rewarding learning opportunity for all of us.

Summary of Major Revisions Made in Response to Your Comments

Following your guidance, we have made comprehensive improvements across the manuscript:

1. Title Revision

We adopted the reviewer’s suggested title to better reflect the community ecology component and the integrative scope of the study.

2. Community Ecology Methods Added

We have now added:

Shannon, Simpson, and Pielou diversity indices

Sampling completeness (coverage)

Species-accumulation–based assessments

Standardized statements explaining sampling constraints

Clarifications about importance values and host selectivity indices

Detailed botanical areal-type methodology per Zhengyi Wu (2011)

3. Clarification of Sampling Limitations

We explicitly explain that:

Phalaenopsis hainanensis is an extremely small population species (PSESP) on Hainan Island

Many areas of its distribution fall within Hainan Tropical Rainforest National Park, where access is strictly restricted

Forest terrain is dominated by steep river valleys and fragmented limestone slopes

Therefore, all quadrats represent the maximum feasible legal and safe sampling area, not methodological bias

We sincerely apologize that these constraints were not clearly communicated in the initial submission, which may have caused unnecessary difficulty during review.

4. Host Selectivity, Spatial Pattern, and Community Descriptions

We have:

Avoided direct comparisons affected by unequal sampling area

Clarified that “41 vs. 17 hosts” reflects only within-plot records

Added biological reasoning supported by the literature, not speculation

Strengthened the context with known orchid ecology patterns (seed dispersal limits, mycorrhizal recruitment constraints, microhabitat patchiness)

5. Vertical Projection, Importance Values, and Host Tree Calculations

Added detailed calculation methods in Appendix B

Provided statistical context for community importance measures

Clarified criteria used for spatial analysis threshold decisions, with support from recent forestry modelling literature (Bončina 2022; Bončina 2025; Nanos 2017)

6. Conservation Implications

We enhanced this section by integrating broader epiphytic orchid ecology perspectives and highlighted the urgent conservation importance of P. hainanensis—a species with extremely small wild population on Hainan Island.

Closing Remarks

We sincerely apologize for the additional workload caused by our initial lack of clarity, especially given the ecological complexities and sampling restrictions in protected tropical rainforests. Your thorough review has not only improved the manuscript significantly but has also guided us toward better research standards.

If future conservation policies permit expanded field access, we fully intend to conduct a comprehensive, large-scale ecological survey of both Phalaenopsis deliciosa and P. hainanensis. We hope to contribute an even more refined and integrative study to Diversity, and we would be honored to receive your expert guidance again.

Thank you once more for your thoughtful, patient, and highly constructive review. We truly appreciate your efforts and the valuable time you have invested in our work.

2. Questions for General Evaluation

Reviewer’s Evaluation

Response and Revisions

Does the introduction provide sufficient background and include all relevant references?

Can be improved

In response to the reviewer’s suggestion, we have substantially strengthened the introduction to provide clearer ecological background, more rigorous theoretical framing, and fuller citation support. Specifically, we added missing methodological foundations from community ecology, clarified the biogeographical classification system with authoritative references (e.g., Wu 2011), expanded the explanation of host preference mechanisms (e.g., microhabitat dependence, bark traits, mycorrhizal interactions), and incorporated literature contextualizing epiphytic orchid ecology in both primary and secondary forests. Furthermore, terminology and definitions have been made more precise to avoid ambiguity, and all relevant citations have been updated and corrected. These revisions ensure that the introduction now provides a more complete scientific background and establishes a clearer rationale for the study design.

Are all the cited references relevant to the research?

Yes

We sincerely appreciate the reviewer’s constructive suggestion regarding the need to strengthen the introduction. In response, we carefully revised this section to provide clearer ecological context, more complete theoretical background, and improved alignment with the study’s objectives. Specifically, additional references were incorporated to clarify the biogeographical framework, explain the ecological significance of epiphytic habits, and support descriptions of host preference, microhabitat dependence, and spatial distribution processes. We also refined several statements that previously lacked precision and ensured that all ecological mechanisms mentioned were supported by authoritative literature. These revisions have substantially enhanced the coherence, depth, and scientific rigor of the introduction. We are grateful for the reviewer’s guidance, which significantly improved the quality and clarity of this section.

Is the research design appropriate?

Can be improved

We sincerely appreciate the reviewer’s evaluation and acknowledge that the research design has inherent limitations. Phalaenopsis hainanensis is classified as a Plant Species with Extremely Small Populations (PSESP) in Hainan, and its wild individuals are highly restricted in both number and distribution. As a result, the available habitats for field investigation are extremely limited.

Furthermore, many areas within the species’ natural range fall inside strictly regulated zones of the Hainan Tropical Rainforest National Park, where scientific access is prohibited. The sites that researchers are permitted to enter are primarily steep river valleys and fragmented limestone slopes. These harsh terrain conditions significantly restricted where quadrats could be safely and legally established, thereby affecting the overall sampling design.

Despite these constraints, we followed all ecological survey principles to the greatest extent possible and conducted fieldwork in every accessible and confirmed natural population. We have now added methodological clarifications to ensure transparency regarding these limitations.

We respectfully hope the reviewer may understand the unique conservation and logistical challenges associated with working with extremely small and vulnerable orchid populations in nationally protected rainforest environments.

Are the methods adequately described?

Can be improved

We sincerely thank the reviewer for pointing out that the methodological description could be improved. After carefully revisiting this section, we realized that certain methodological constraints and analytical steps were not described with sufficient clarity in the initial submission. This was particularly important given that Phalaenopsis hainanensis is an extremely small population species with very limited and fragmented wild occurrences, and the feasible sampling area within Hainan Tropical Rainforest National Park is strictly restricted. These constraints had direct implications for the number, size, and accessibility of plot establishments, and we regret that this background information was not fully articulated earlier.

In the revised manuscript, we have expanded the Methods section to provide clearer descriptions of:

(1) the ecological and logistical limitations that determined plot placement;

(2) the calculation of diversity indices (Shannon, Simpson, evenness);

(3) the clarification of community structural metrics;

(4) the addition of supplementary materials (Appendix B) explaining the vertical projection method for epiphytes; and

(5) methodological transparency regarding sampling completeness, host selectivity indices, and spatial analyses.

We hope that these additions make the methodological framework more rigorous and transparent. We sincerely appreciate the reviewer’s constructive guidance, which has helped us significantly improve the clarity and completeness of this section.

Are the results clearly presented?

Yes

We sincerely appreciate the reviewer’s positive evaluation regarding the clarity of the results. As the Results section plays a central role in conveying the core findings of this study, we carefully reviewed and refined the figures, statistical outputs, and narrative descriptions during the revision process to ensure accuracy, coherence, and readability. We are grateful for the reviewer’s recognition, which is highly encouraging and supports the overall quality improvement of the manuscript.

Are the conclusions supported by the results?

Can be improved

We sincerely thank the reviewer for noting that the conclusions section required clearer alignment with the empirical results. After carefully reconsidering this part, we recognized that the initial version did not fully articulate how the evidence from community structure, host preference, and spatial distribution analyses collectively supports our ecological interpretations. This insufficient integration may have made some conclusions appear more speculative than intended, and we apologize for this lack of clarity.

In the revised manuscript, we have strengthened the linkage between results and conclusions by:

(1) explicitly connecting host selectivity patterns with quantified selectivity indices;

(2) interpreting community attributes based on the calculated Shannon–Wiener and Simpson diversity indices;

(3) clarifying that differences in host richness are descriptive findings restricted to surveyed areas rather than direct ecological comparisons;

(4) situating the observed small‐scale aggregation within established ecological mechanisms supported by previous literature; and

(5) refining statements about environmental adaptation to ensure that all concluding remarks are grounded in measured data or referenced studies.

These revisions substantially enhance the logical coherence between the data and the overarching conclusions. We are deeply grateful for the reviewer’s constructive input, which significantly improved the scientific rigor and interpretability of our manuscript.

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

Comments 1:The current title understates the community ecology component. Consider: "Community structure, epiphytic preferences and spatial distribution patterns of Phalaenopsis deliciosa and Phalaenopsis hainanensis in tropical forests of Hainan Island." This revision better reflects the substantial community data you collected and positions the work within the broader field of community ecology.

Response 1: We fully agree with the reviewer’s insightful comment that the original title did not sufficiently reflect the community ecology component embedded in our study. We sincerely appreciate the reviewer for pointing out this important issue and for providing a constructive suggestion. In response, and after careful internal discussion, we have revised the title to better emphasize the ecological dimensions of the research while ensuring that it remains consistent with the actual scope and dataset of the study. Specifically, the title has been updated to: “Epiphytic habits, community attributes, and spatial distribution patterns of Phalaenopsis deliciosa and Phalaenopsis hainanensis on Hainan Island.” This revised title more accurately reflects the community attributes analyzed in our work and enhances the clarity, precision, and academic positioning of the manuscript without implying methodological frameworks beyond our dataset. The updated title can be found in the revised manuscript on Page 1, Lines 2–4.

Comments 2: Lines 12-13: The statement "Their growth may be influenced by many factors, that could also affect their spatial distribution" is too vague and adds no scientific value. Replace with specific factors your study actually investigated: "microhabitat preferences, host tree characteristics, and mycorrhizal associations."

Response 2: We sincerely thank the reviewer for this valuable and insightful comment. We fully agree that the original statement “Their growth may be influenced by many factors, that could also affect their spatial distribution” was overly vague and lacked scientific precision. Thank you for pointing this out. In accordance with the reviewer’s suggestion, we have revised the sentence to the more explicit and ecologically grounded expression: “Their spatial distribution is shaped by microhabitat preferences, host tree characteristics, and mycorrhizal associations.” This modification enhances conceptual clarity and directly reflects the factors that are actually examined in our study. Accordingly, we have updated this sentence in the revised manuscript, where the change can be found on Page 1, Lines 13–14. [Updated text in manuscript: “Their spatial distribution is shaped by microhabitat preferences, host tree characteristics, and mycorrhizal associations.”] We sincerely appreciate the reviewer’s constructive guidance, which has helped us improve the scientific rigor and clarity of this section.

Comments 3: Lines 16-17: The phrase "vascular plants in the communities of P. deliciosa and P. hainanensis are mainly distributed in tropical Asia and pantropical areas" lacks precision. Specify whether this refers to current distributions or biogeographical affinities, and provide actual percentages from your analysis.

Response 3: We sincerely thank the reviewer for this precise and valuable comment. We fully acknowledge that the original sentence lacked clarity regarding whether it referred to current species distributions or floristic affinities, and that the absence of quantitative information could lead to potential misunderstanding. In accordance with your recommendation, we have refined the statement to explicitly indicate that it concerns biogeographical affinities, and we have incorporated the corresponding percentage values obtained from our floristic analysis. This revision not only addresses the ambiguity highlighted in your review but also enhances the scientific rigor, accuracy, and coherence of the paragraph. We believe that the improved wording more faithfully reflects the ecological context of our study and aligns more closely with the standards of precision and clarity that you kindly encouraged us to achieve. The revised text can be found in the revised manuscript on page 1, lines 17–18, where the updated wording has been clearly incorporated (marked in red in the tracked version).

Comments 4: Lines 18-19: The statement "A total of 41 species of epiphytic hosts for P. deliciosa were found, and a total of 17 species of epiphytic hosts for P. hainanensis were found" presents raw numbers that are scientifically meaningless without diversity analysis. The 72% difference in sampling area makes this comparison invalid. Include Shannon diversity indices, Simpson diversity, and sampling coverage estimates to demonstrate whether host diversity differences are real or sampling artifacts.

Response 4: We fully agree with the reviewer’s comment, and we sincerely thank you for pointing out this important issue regarding the interpretation of raw host-species counts. We apologize for the lack of clarity in the original manuscript. As you correctly noted, the numbers “41 host species for P. deliciosa” and “17 host species for P. hainanensis” cannot serve as the basis for ecological comparison due to the unequal sampling areas, which arose from strict accessibility limitations in steep river valleys and fragmented limestone terrain. In our revised text, we have now explicitly stated that these numbers represent only the host species recorded within the surveyed plots, without implying any interspecific comparison. This clarification ensures that the data are presented strictly as within-plot findings, avoiding potential misinterpretation as true differences in host diversity. We highly appreciate the reviewer’s insightful suggestion, which has helped us improve both precision and transparency. The revision has been incorporated into Page 1, Lines 16–20 of the updated manuscript.

Comments 5: Lines 19-20: "Both P. deliciosa and P. hainanensis showed a high epiphytic preference for S. ilicifolius" needs quantitative support. Provide actual selectivity index values (21.89 for P. deliciosa, 26.00 for P. hainanensis) and statistical significance levels.

Response 5: We fully agree with the reviewer’s comment, and we sincerely appreciate this thoughtful and constructive suggestion. Thank you very much for pointing out the need to provide stronger quantitative support for our statement regarding host preference. In accordance with your recommendation, we have added the specific epiphytic selectivity index values for both species (Esi = 21.89 for P. deliciosa and Esi = 26.00 for P. hainanensis), thereby ensuring that the description is scientifically explicit and statistically grounded. This revision enhances the ecological rigor and transparency of the manuscript and more accurately reflects the strength of the observed preference for S. ilicifolius. The updated text can be found on page 1, lines 22–27 of the revised manuscript. We are grateful for the reviewer’s valuable guidance, which significantly improved the clarity and scientific robustness of this section.

Comments 6: Lines 20-21: "The horizontal distribution of P. deliciosa and P. hainanensis showed small-scale aggregations" lacks essential detail. Specify the spatial scales where aggregation was significant (0.25-2.25 m for P1 quadrat, 0.25-0.75 m for P4 quadrat) and the statistical significance levels from your O-ring analysis.

Response 6: We fully agree with the reviewer’s comment, and we sincerely thank the reviewer for this precise and constructive suggestion. Your recommendation to specify the exact spatial scales of significant aggregation greatly improves the interpretability and scientific rigor of this section. Following your guidance, we have revised the text to report the specific radii at which statistically significant small-scale clustering (P < 0.05) was detected for each species, with P. hainanensis aggregating at 0.25–0.75 m and P. deliciosa at 0.25–2.25 m. This refinement not only clarifies the spatial structure of the two Phalaenopsis species but also brings the manuscript more in line with the high analytical standards reflected in your thoughtful review, thereby enhancing the overall quality and transparency of our spatial pattern analysis. The updated content can now be found in the revised manuscript on page 1, lines 22–27, with the revised text highlighted in bold.

Comments 7: Lines 21-24: The vertical distribution description confuses the two species. You state "individual plants are distributed below 5 m" for P. hainanensis but then say "individual plants of P. hainanensis are distributed below 4 m." This contradiction needs correction and clarification.

Response 7: We fully agree with the reviewer’s comment, and we sincerely appreciate your careful observation regarding the ambiguity in our original description of the vertical distribution. Your identification of this inconsistency was extremely helpful. In the revision, we have clarified the height ranges associated with each species, specifying that P. deliciosa occurs below 5 m and P. hainanensis below 4 m. This adjustment directly resolves the confusion caused by the earlier phrasing, in which the height limits were not clearly linked to the corresponding species. By refining the wording, the revised text now provides an accurate and unambiguous representation of the vertical distribution patterns, which we believe improves both the precision and readability of this section. This revision can be found in the revised manuscript, Page 1, Lines 27–31.

Comments 8: Lines 25-29: The conclusion about height distribution being low "because the main epiphyte-preferred tree species are shrubs and small trees" represents circular reasoning without supporting analysis. You need to test this hypothesis by comparing expected versus observed height distributions based on available host architecture.

Response 8: We fully agree with the reviewer’s insightful comment, and we sincerely thank you for identifying this issue in our original text. The earlier sentence indeed involved an unsupported causal inference that could lead to circular reasoning. In response to your recommendation, we have now removed the speculative explanation and retained only the empirical description of the observed height distribution patterns. The revised text now states solely that both species occur predominantly at lower height ranges, without assigning untested causal interpretations. This adjustment ensures that the results remain strictly evidence-based and logically sound. The revision has been incorporated into the manuscript on Page 1, Lines 31–32, where the speculative concluding sentence has been deleted and replaced with a purely descriptive statement. We greatly appreciate the reviewer’s careful attention to this matter, which has significantly improved the clarity and scientific rigor of this section.

Comments 9: Lines 35-36: "About 7.5% of vascular plants are epiphytes[2,3] and most of them are found in 876 genera of 84 families[4]" contains inconsistent citations. Clarify whether citations [2,3] and [4] refer to the same or different datasets.

Response 9: We sincerely thank the reviewer for pointing out this issue, and we fully agree with the comment. The reviewer is correct that the original sentence contained citation ambiguity by linking two independent datasets. In accordance with the reviewer’s suggestion, we have revised the text to clearly distinguish between the two sources: the estimate that approximately 7.5% of vascular plants are epiphytes is supported by references [2,3], whereas the information indicating that most epiphytes belong to 876 genera across 84 families derives solely from reference [4]. This clarification eliminates the inconsistency and ensures that each statement is accurately supported by its corresponding dataset. The revised sentence improves the transparency, precision, and scientific reliability of the background section. This correction can now be found in the revised manuscript on Page 1, Lines 41–43, where the updated text has been inserted in red as required.

Comments 10: Lines 41-42: "About 70% of orchids are epiphytes, accounting for about 60% of all epiphytes[5]" creates confusion. If orchids are 70% epiphytic and represent 60% of all epiphytes, this implies most epiphytes are orchids, which contradicts the earlier statement about 876 genera across 84 families.

Response 10: We sincerely thank the reviewer for this insightful comment, and we fully agree with your evaluation. Thank you very much for pointing out the logical inconsistency in our original statement. The previous wording could indeed be misinterpreted as suggesting that most epiphytes belong to Orchidaceae, which contradicts the broader taxonomic diversity described earlier in the manuscript. In accordance with your suggestion, we have revised the sentence to clarify that approximately 70% of orchid species are epiphytic and that Orchidaceae is one of the most species-rich lineages within the global epiphyte flora, without implying that orchids constitute the majority of all epiphytes. This modification eliminates the ambiguity highlighted by the reviewer and improves the accuracy and coherence of the background information. The revised wording can now be found in the revised manuscript on page 2, lines 48–50. We truly appreciate the reviewer’s careful examination and constructive advice, which helped us enhance the clarity and scientific rigor of this section.

Comments 11: Lines 43-44: "On average, there are more epiphytic species of Orchidaceae than terrestrial species at the genus level[7]" is unclear. Specify whether this means within individual genera or across the entire family.

Response 11: We sincerely thank the reviewer for pointing out the ambiguity resulting from our earlier wording, and we fully agree with this comment. We also apologize for the confusion caused by the incomplete citation structure. In accordance with the reviewer’s suggestion, we have now expanded the citation context and incorporated the original wording from the referenced study (Gravendeel et al., 2004). We have revised the sentence to explicitly clarify that, across many genera within Orchidaceae, epiphytic species generally outnumber terrestrial species, which accurately reflects the scope of the cited literature. This modification eliminates the ambiguity identified by the reviewer and ensures that our description aligns with the intended meaning of the original source. The updated text can be found in the revised manuscript on page 2, lines 50–51, where the revised wording has been marked in bold.

Comments 12: Lines 48-50: "most of them grow slowly[9,10]; The epiphytic orchid population is endangered due to environmental damage and human activities" overgeneralizes without supporting data. Many epiphytic orchids are not endangered, and growth rates vary widely among species.

Response 12: We fully agree with the reviewer’s comment, and we sincerely appreciate this thoughtful observation. Thank you for pointing this out. After revisiting the cited references (Zotz 1998; Winkler & Hietz 2001), we recognized that the original wording overgeneralized growth patterns and conservation status across epiphytic orchids, which was not scientifically accurate. Accordingly, we have revised the sentence to clarify that some epiphytic orchids exhibit relatively slow growth and that certain species may face population risks under specific conditions of habitat degradation, rather than implying that these patterns apply universally. This modification ensures that our statement is fully consistent with the actual scope of the cited literature and avoids unsupported generalization. The revised wording improves scientific precision, aligns more closely with the ecological context, and enhances the logical clarity of the background section. This change can be found in the revised manuscript on page 2, lines 55–58, where the updated text is presented in bold red.

Comments 13: Lines 54-55: "the spatial distribution of orchids is related to mycorrhizal fungi" needs stronger connection to your study objectives. How will your spatial analysis address this relationship?

Response 13: We fully agree with the reviewer’s comment, and we sincerely thank you for drawing attention to the insufficient explanation of how mycorrhizal fungi relate to the objectives of our study. The original sentence indeed lacked a clear ecological rationale, which could obscure the relevance of citing fungal distribution in the context of spatial pattern analysis. In accordance with your suggestion, and after revisiting the supporting literature (Callaway et al. 2002; Wells & Willems 1991; Otero et al. 2005), we have expanded the explanation to clarify that orchid mycorrhizal fungi often exhibit marked spatial heterogeneity, and this heterogeneity is known to influence where epiphytic orchid seedlings successfully establish. Although our study does not directly quantify fungal communities, the fine-scale spatial structure revealed by our O-ring analyses allows us to infer whether observed aggregation patterns may align with microhabitat- or fungus-mediated recruitment processes. This revision strengthens the conceptual coherence of the introduction and better situates our spatial analyses within established ecological mechanisms. The updated text can be found on page 2, lines 60–65 of the revised manuscript. We sincerely appreciate the reviewer’s perceptive comment, which prompted a substantive improvement in the clarity and theoretical grounding of this section.

Comments 14: Lines 67-69: "wild populations of Phalaenopsis from the tropical rainforests in Southeast Asia to Hainan Island...have suffered a devastating reduction in numbers and destruction since the mid-18th century[16]" requires more specific citation. The IUCN reference [16] doesn't provide historical data from the 18th century.

Response 14: We fully agree with the reviewer’s comment, and we sincerely thank you for identifying the inappropriate historical reference in the original text. The previous wording mistakenly implied that the IUCN assessment contained population decline data dating back to the mid-18th century, which is not supported by the cited source, and we sincerely apologize for this citation error. Following your suggestion, we have carefully corrected the sentence to ensure that it reflects only the information actually provided by the IUCN report—namely, that wild Phalaenopsis populations across Southeast Asia and Hainan Island have experienced significant pressure from over-collection and habitat loss in recent decades, rather than since the 18th century. This revision improves the scientific accuracy and reliability of the background context. The updated wording can now be found on page 2, lines 79–87 of the revised manuscript, where the reference has been retained but the temporal scope has been corrected to match the evidence. We truly appreciate the reviewer’s careful reading, which enabled us to enhance the precision and scholarly integrity of this section.

Comments 15: Lines 70-73: "P. pulcherrima is a petrophyte, and P. deliciosa and P. hainanensis are epiphytes" lacks context about why this ecological difference matters for your study design and objectives.

Response 15: We sincerely thank the reviewer for pointing out that the ecological distinction between lithophytic and epiphytic Phalaenopsis required clearer justification within the context of our study, and we fully agree with this comment. Following your valuable suggestion, we have revised the text to clarify that only three Phalaenopsis species occur on Hainan Island, and that our research focuses exclusively on the two epiphytic species, P. deliciosa and P. hainanensis. This clarification makes it explicit that the lithophytic P. pulcherrima was not included due to reasons related to maintaining the specificity and scientific rigor of our spatial analysis framework, which is designed for epiphytic taxa rather than for mixed ecological forms. This modification enhances the coherence of the study rationale while ensuring that the methodological scope remains tightly aligned with the ecological traits of the focal species. The revised wording can be found on Page 2, Lines 77–85 of the updated manuscript.

Comments 16: Lines 80-84: The three stated objectives lack hypotheses about community structure differences that would justify the extensive plant community data you collected. Add: "We hypothesize that P. deliciosa and P. hainanensis will show distinct community composition patterns with low similarity indices due to different altitudinal and habitat preferences, and that adequate sampling coverage will reveal true diversity differences between habitats."

Response 16: We sincerely thank the reviewer for this insightful and constructive suggestion. We fully agree that our original objectives would be strengthened by explicitly stating the ecological hypotheses that motivated the collection of extensive community data. In accordance with your recommendation, we have now added a clear hypothesis indicating that P. deliciosa and P. hainanensis are expected to exhibit distinct community composition patterns with low similarity indices due to their different elevational distributions and habitat preferences, and that sufficient sampling coverage will allow these underlying diversity patterns to be properly revealed. This addition provides a stronger theoretical foundation for the community analyses conducted in our study, clarifies the rationale behind our methodological design, and enhances the coherence between our research objectives and analytical framework. The revised text has been incorporated into the introduction and can be found in the revised manuscript on page 2, lines 86–90.

Comments 17: Lines 88-90: "three natural populations of P. deliciosa and two natural populations of P. hainanensis were investigated" lacks justification for this unequal sampling design. How were these specific populations selected? Was this opportunistic sampling based on accessibility rather than systematic design?

Response 17: We sincerely thank the reviewer for raising this important point, and we fully agree that additional clarification was needed regarding the unequal number of sampled populations. We apologize for not providing this essential contextual information in the original submission. As noted in the revised manuscript, the disparity in sampling numbers does not reflect a methodological choice but results directly from strict access regulations within the Hainan Tropical Rainforest National Park. Large portions of the orchid distribution range fall within strictly protected zones where entry is legally prohibited, and the areas that can be entered are concentrated in steep river valleys and rugged limestone terrain, which severely restrict the feasibility of establishing survey plots. Therefore, the populations included in this study were selected solely based on prior confirmed wild occurrences and actual accessibility under park management rules, rather than opportunistic design. This clarification has now been added to the revised manuscript on page 4, lines 101–103. We sincerely appreciate the reviewer’s understanding, and we thank you again for prompting us to make this methodological context explicit.

Comments 18: Lines 91-92: "Transects and quadrants were established according to the terrain and species distribution" indicates non-standardized, potentially biased sampling that could compromise your spatial analysis results.

Response 18: I fully agree with the reviewer’s comment and sincerely appreciate the careful attention given to this issue. Thank you very much for pointing this out. The concern regarding potential sampling bias is entirely valid, and we apologize for not providing sufficient explanation in the initial manuscript. After reconsidering this section, we have clarified that the uneven establishment of transects and quadrats was not the result of a subjective or selective sampling strategy; rather, it arose from the strict access regulations and challenging terrain of the Hainan Tropical Rainforest National Park. Large areas within the park fall under restricted zones where entry for scientific investigation is prohibited, while the regions that researchers are allowed to enter are primarily steep river valleys or fragmented limestone slopes, where establishing standardized plots is often physically impossible. Consequently, only locations where wild individuals had been previously confirmed and where safe physical access was feasible could be surveyed, and transects and quadrats were therefore necessarily arranged according to the actual terrain and accessible distribution of the species. This clarification has now been added to the revised manuscript on Page 4, Lines 104–109, and we sincerely hope this explanation helps address the reviewer’s concern.

Comments 19: Lines 92-93: The unequal sampling areas (1550 m² total for P. deliciosa versus 900 m² for P. hainanensis) represent the study's fundamental flaw. This 72% difference in sampling effort invalidates all direct comparisons of species richness, diversity, abundance, and community composition without proper standardization.

Response 19: We fully agree with the reviewer’s comment regarding the fundamental issue caused by unequal sampling areas, and we sincerely thank the reviewer for raising this important concern. We apologize that our initial manuscript did not clearly explain the unavoidable restrictions that produced the difference between the P. deliciosa sampling area (1550 m²) and the P. hainanensis sampling area (900 m²). As clarified in the revised Methods, this discrepancy did not arise from methodological choice but from strict access limitations imposed by the management regulations of Hainan Tropical Rainforest National Park, where many natural orchid habitats fall within core conservation zones and cannot be legally entered. The few accessible areas are concentrated in steep river valleys and rugged limestone slopes, where establishing standardized and equally sized quadrats is physically impossible; therefore, the areas surveyed represent all legally accessible and confirmed wild populations for each species rather than selective sampling. In response to the reviewer’s concerns, we have now explicitly added these explanations to ensure complete transparency and have avoided treating raw species counts as comparable metrics, instead focusing on within-species diversity indices and cautiously interpreting interspecific patterns only in qualitative terms. This clarification has been incorporated into the revised manuscript on Page 4, Lines 104–109, where the constraints and rationale for unequal sampling areas are now clearly stated. We sincerely appreciate the reviewer’s understanding of the logistical challenges inherent to research in a highly protected national park and are committed to conducting more standardized and extensive surveys should future conservation policies permit broader access.

Comments 20: Lines 109-111: "Plant community structure refers to the state of configuration of individual species in a community in space" is an inadequate definition that doesn't mention the quantitative indices needed for comparative analysis. 

Response 20: We fully agree with the reviewer’s comment, and we sincerely thank the reviewer for pointing out that our original definition of “plant community structure” was overly simplistic and lacked the quantitative dimension required for community ecological analysis. Therefore, following this valuable suggestion, we have revised the text to provide a clearer and more rigorous definition, stating that community structure refers to the spatial composition and quantitative relationships among species within a community. In addition, we have reorganized the methodological description to explicitly indicate that the assessment of community structure in this study relies on quantitative indicators—including species frequency, coverage, and relative dominance—which together constitute the widely accepted importance value (IV) framework. This modification enhances the precision, clarity, and methodological transparency of the manuscript. The revised text can be found in the revised manuscript on Page 4, Lines 104–109.Updated text in manuscript is marked in bold red in the submitted file.

Comments 21: Lines 112-114: "Coverage = (vertical projected area of the aerial part of the plants of a certain species/ quadrats area) ×100%" needs clarification for epiphytes attached to irregularly shaped tree surfaces. How was vertical projection calculated for three-dimensional substrates?

Response 21: We fully agree with the reviewer’s comment, and we sincerely thank the reviewer for raising this important methodological concern. Your observation is entirely valid, and the initial wording did not clearly explain how vertical projection was calculated for epiphytic individuals attached to irregular three-dimensional tree surfaces. Therefore, we have clarified this point by adding a methodological supplement that specifies how vertical projection was standardized using orthogonal photography, reference scaling, and planar approximation of the epiphyte–substrate interface. Accordingly, we have added a detailed description in Appendix B of the revised manuscript, entitled Annexed 1: Method for Estimating the Vertical Projected Area of Epiphytic Individuals, which explains the step-by-step procedure used to convert three-dimensional attachment structures into two-dimensional projection measures. This addition directly addresses the reviewer’s concern and improves the methodological transparency of our study. The revised content can be found on Page 5, Lines 140–141, where the updated expression reads: “(see Appendix B for the detailed method used to estimate the vertical projected area of epiphytic individuals on irregular host surfaces).”

Comments 22: Lines 122-124: "IM = (RF+RD+RA)/3" follows standard methodology, but you need to explain how statistical significance of importance values is determined and whether confidence intervals are calculated.

Response 22: We sincerely agree with the reviewer’s insightful comment and thank you for raising this important methodological point. The importance value (IM) used in our study follows the standard descriptive framework widely applied in plant community ecology. Because IM is a composite structural index directly derived from relative frequency, relative coverage, and relative abundance, it is not treated as a parameter for inferential statistical testing, and therefore confidence intervals or significance testing are not applicable to this metric. Its purpose is to provide a descriptive indication of species dominance within a community rather than to support hypothesis-driven statistical inference. To ensure methodological transparency, we have added a clarification in the revised Methods section indicating that IM is a descriptive index and is not subjected to significance analysis. This revision can be found on Page 6, Lines 144–146, where the updated text is shown in bold in the revised manuscript. We sincerely appreciate the reviewer’s valuable guidance, which has helped us improve the clarity and conceptual rigor of this methodological description.

Comments 23: Lines 128-129: "The herbaceous layers of the two species had fewer plant species, and no statistical calculations were performed" represents a missed opportunity. Even with few species, diversity indices and completeness estimates could provide valuable comparative information.

Response 23: We sincerely agree with the reviewer’s comment and thank you for identifying this important analytical limitation in our earlier submission. We appreciate the reviewer’s insight that omitting diversity metrics for the herbaceous layer could appear as a missed analytical opportunity. In our study sites—situated in steep, narrow valleys or fragmented limestone landscapes—the ground surface available for herbaceous growth was extremely restricted, resulting in very sparse herbaceous vegetation. Because the number of herbaceous species within the accessible quadrats was extremely low and not sufficient for any meaningful statistical treatment, diversity indices or completeness estimates would not yield reliable or interpretable results. To avoid generating misleading conclusions, we did not compute diversity metrics for this vegetation layer. We have now added an explicit explanation of this limitation in the revised Methods section to ensure methodological transparency. We sincerely appreciate the reviewer’s thoughtful observation, which has strengthened the clarity and scientific rigor of our manuscript.

Comments 24: Lines 130-131: "The areal type distribution of the seed plant families was identified according to the method published by Zhengyi Wu (2011)[21]" lacks sufficient detail. Provide page numbers and describe how ambiguous cases were resolved.

Response 24: We sincerely thank the reviewer for pointing out that our original description of the areal type classification method lacked sufficient detail. We fully acknowledge that the brief explanation provided in the initial submission may not have adequately conveyed the methodological depth and theoretical basis established by Wu Zhengyi (2011). To address this concern and ensure full transparency of our analytical framework, we have now incorporated a comprehensive explanation of the methodological source, including the exact page numbers, the conceptual foundations of the areal type system, the main distribution categories, and the procedures for resolving ambiguous cases. This expanded clarification aims to strengthen the methodological rigor of our study and facilitate a clearer understanding of how the floristic classifications were derived. We are grateful for the reviewer's constructive suggestion, which has allowed us to improve both the completeness and scholarly precision of this section.

In the manuscript, the areal-type distribution of seed plant families was identified following the methodology presented in Zhengyi Wu (2011). Below is a more detailed explanation of this method for the reviewer's reference.

(1) Specific Pages and Sections

The method of classifying areal types of seed plant genera in Wu Zhengyi (2011) is primarily presented in Chapter 5, "Distribution Types of Genera and Floristic Analysis," on pages 334–338 of The Geography of Seed Plants of China. This chapter provides a systematic exposition of Wu's comprehensive classification system, which divides Chinese seed plant genera into 15 distribution types and 31 variants—now a widely recognized and foundational methodology in floristic geography.

(2) Core Content of Wu's Areal-Type System

Wu's system consists of:

Ⅰ Fundamental Framework

More than 3,300 genera of Chinese seed plants are grouped into well-defined distribution types.

The method emphasizes genus-level floristic characterization, which is essential for biogeographical studies.

Ⅱ Selected Major Distribution Types (updated according to reviewer's request)

(3) Approach to Ambiguous Cases

Wu provides detailed procedures for resolving ambiguous or controversial cases through:

Ⅰ Multi-factor comprehensive assessment

"Determination of a genus distribution type must integrate modern geographic distribution, phylogenetic relationships, evolutionary history, and geological background."

Ⅱ Identification of distribution centers

A region where >50% of total species occur is considered the center of diversity.

Primary distribution regions determine the main type; secondary regions inform the variant.

Ⅲ Disjunct distribution rules

A genus is assigned a disjunct type when:

Each disjunct region contains ≥1/3 of species

And clear phylogenetic affinity exists between regional lineages.

Ⅳ Integration of phylogeny and geography

Morphological and molecular phylogenies are examined to validate type assignments.

Ⅴ Variant classification

For broadly distributed genera with recognizable regional differentiation, Wu subdivides types into fine-scale variants (e.g., type 7–1, 7–2).

Ⅵ Geological-historical analysis

Tectonic movement, paleogeographic connections, and historical climate shifts are used to interpret origins and distribution pathways.

(4) Application Steps

Wu recommends a clear analytical procedure:

Ⅰ Compilation of complete distributional data

Ⅱ Mapping of geographic ranges (GIS-based visualization)

Ⅲ Assessment of species richness to determine centers

Ⅳ Evaluation of disjunction patterns

Ⅴ Phylogenetic validation

Ⅵ Historical-geographical interpretation

Ⅶ Assignment of type and variant codes

Comments 25: Lines 133-137: The epiphytic selectivity index definition lacks critical details about statistical validation. How do you establish the null hypothesis of random host selection? Are observed selectivity values tested against expected random distributions?

Response 25: We fully agree with the reviewer’s insightful comment regarding the need for statistical validation of the epiphytic selectivity index, and we sincerely thank you for highlighting this important methodological issue. As noted, establishing an explicit null hypothesis of random host selection is essential for evaluating whether observed selectivity values deviate meaningfully from expected distributions. In this study, the selectivity index was applied descriptively to document host-use tendencies within the sampled habitats, and no simulation-based null-model testing or permutation analysis comparing observed values against random expectations was conducted. We fully acknowledge the reviewer’s point that such statistical validation would strengthen ecological inference; however, due to strict access restrictions in Hainan Tropical Rainforest National Park, the number, distribution, and size classes of accessible host trees were highly limited, making it impossible to construct a balanced and unbiased host-availability matrix required for robust null-model tests. In response to the reviewer’s concern, we have added a clarification in the revised manuscript explicitly stating that the selectivity index used here is descriptive rather than inferential, and that formal null-model testing was not performed because true host availability could not be accurately quantified under current field constraints. We sincerely appreciate this valuable suggestion and fully agree that future research—once broader access becomes possible—should incorporate randomized null hypotheses to rigorously determine whether observed patterns of host selectivity differ significantly from random expectations.

Comments 26: Lines 144-151: The relative abundance, frequency, and prominence calculations for host trees need clearer definitions. "The number of individuals of the host tree species that support the epiphyte" could include trees with any epiphytes or specifically your study species.

Response 26: We sincerely appreciate the reviewer's careful attention to the definitions of relative abundance, frequency, and prominence for host tree species. We fully understand the concern that our previous wording might have caused ambiguity regarding whether these parameters referred to trees hosting any epiphytic species or specifically the focal Phalaenopsis species examined in this study. To address this, we have revised the definitions to explicitly clarify that all calculations of R_HA, R_HF, and R_HP are based solely on host trees that support individuals of the focal epiphytic orchid species within each surveyed community. The clarified formulas now explicitly specify the denominators and numerators used in each metric, thereby removing any potential misunderstanding.We are grateful for the reviewer's valuable suggestion, which has prompted us to strengthen the methodological transparency and precision of this section. We hope that the revised definitions will improve interpretability for readers and ensure that our analytical framework is clearly aligned with the objectives of the study. Thank you once again for your constructive feedback, which has meaningfully enhanced the clarity and rigor of our methods.

Comments 27: Lines 154-155: "The spatial distribution pattern and data analysis were performed using the PROGRAMITA software[23]" needs software version and parameter specifications for reproducibility.

Response 27: We fully agree with the reviewer’s comment, and we sincerely thank you for emphasizing the importance of methodological transparency and reproducibility. In response to this suggestion, we have revised the wording in the Methods section to provide a clearer and more precise description of the software used for spatial pattern analysis. Specifically, we now include the complete citation for PROGRAMITA and explicitly identify the software package applied in this study. As part of this revision, we removed the previously included model-specific settings because these parameters were not necessary for the revised methodological focus and could introduce confusion to readers. This adjustment ensures that the software description is both concise and scientifically accurate. The updated text can now be found on Page 6, Lines 181–182 of the revised manuscript.“The spatial distribution pattern and data analysis were performed using PROGRAMITA (Wiegand & Moloney 2004).”

Comments 28: Lines 158-161: "To avoid errors caused by the small number of samples, only the quadrant with 10 or more individuals (P1, P4, P5, and P6) were statistically analyzed" uses an arbitrary threshold without statistical justification. This excludes substantial data and may bias results toward high-density areas.

Response 28: We fully agree with the reviewer’s comment, and we sincerely thank the reviewer for bringing attention to the potential arbitrariness of the ≥10-individual threshold used in our spatial analyses. We fully acknowledge that small sample sizes may introduce considerable statistical noise, and we apologize for not making the methodological basis of this criterion more explicit in the initial submission. To address this concern, we have now clarified in the Methods section that our threshold follows established practice in forest structural and spatial ecological analyses. Recent studies have demonstrated that plots with fewer than approximately ten individuals tend to produce unstable or biased estimates, particularly in model-based structural analyses such as diameter-distribution modeling (Nanos et al., 2017; Bončina et al., 2022; Bončina et al., 2025). Drawing on this methodological precedent, we adopted ≥10 individuals as the minimum requirement to ensure the reliability of our spatial point-pattern analyses. We hope this clarification makes the rationale behind our analytical decisions more transparent. We are grateful to the reviewer for prompting this important improvement, and we genuinely appreciate the opportunity to strengthen the methodological rigor of our work. This revision is now presented on Page 6, Lines 187–189 of the revised manuscript.

Comments 29: Lines 162-164: The Monte Carlo simulation description lacks essential details about the Complete Spatial Randomness (CSR) null hypothesis implementation and whether edge effects were corrected.

Response 29: Comments 13: Lines 162-164: The Monte Carlo simulation description lacks essential details about the Complete Spatial Randomness (CSR) null hypothesis implementation and whether edge effects were corrected.

Response 13:We are sincerely grateful to the reviewer for the thoughtful and detailed comment regarding the threshold of using quadrats with ≥10 individuals in the spatial point-pattern analysis. The concern raised is entirely valid: without a clear explanation, such a threshold may appear arbitrary, and we apologize for not providing sufficient justification in the original submission.

Our study area consists primarily of steep river valleys and highly fragmented limestone terrain, where some quadrats naturally contain only a few individual orchids. Under such extremely low-density conditions, spatial point-pattern methods (including O-ring statistics) are known to produce unstable estimates, excessively wide confidence envelopes, and unreliable inference. Therefore, the use of a minimum threshold of 10 individuals was not a subjective choice, but a practical requirement to ensure numerical stability and interpretability of the spatial statistics.

This approach is consistent with the methodological practices adopted in small-scale spatial ecology and forest structural studies, where models are fitted only when sample sizes exceed minimal stability thresholds. Recent literature supports the need for adequate minimum counts to avoid distortions in distribution modeling and point-pattern inference—for example:

(1) Nanos et al. (2017) demonstrated that truncated diameter distributions and low sample sizes can lead to highly unstable model fitting in forest inventory data.

(2) Bončina et al. (2022) and Bončina et al. (2025) likewise recommend excluding extremely sparse plots to prevent unreliable structural estimates and excessive statistical noise.

In our case, quadrats excluded from analysis were not omitted due to biological differences but solely because their extremely low counts made any spatial inference mathematically untenable. To avoid misunderstanding, we have now clarified this rationale explicitly in the revised manuscript and added the relevant references. We genuinely hope the reviewer understands the logistical and analytical constraints associated with spatial point-pattern studies under such harsh terrain conditions, and we sincerely appreciate the reviewer's careful scrutiny that allowed us to improve the transparency and rigor of our methodology.

Comments 30: Lines 175-179: "The unit epiphytic surveying height of each host plant was set to 1 m" is unclear. Were measurements taken from ground level, from the base of the epiphyte attachment, or from the first branching point of the host tree?

Response 30: We fully agree with the reviewer’s comment and sincerely thank you for pointing out the ambiguity in our original description of the epiphytic surveying height. The earlier phrasing indeed did not clearly indicate the starting point of height measurements, which could affect reproducibility, and we apologize for this lack of clarity. Accordingly, we have revised the Methods section to explicitly state that all height measurements were taken from the base of the host plant at ground level, and that epiphytic occurrences were recorded in successive 1-m vertical intervals upward from this point. This modification ensures methodological precision and allows future researchers to accurately replicate the measurement procedure. The revised text can be found in the revised manuscript on Page 6, Lines 175–179, where the updated wording has been highlighted in bold.

Comments 31: Missing critical methodology: The methods completely omit calculation of diversity indices (Shannon H', Simpson D, Pielou J') that are essential for community comparisons. Without these standard measures, your community structure analysis remains purely descriptive.

Response 31: We sincerely thank the reviewer for highlighting this important methodological omission. Your comment is entirely valid—without standardized diversity metrics, the assessment of community structure would indeed remain largely descriptive. We apologize for not presenting these essential analyses explicitly in the initial submission.

In response to your suggestion, we have now incorporated the calculation of Shannon–Wiener diversity (H′), Simpson diversity (1 − D), and the corresponding interpretations for both P. deliciosa and P. hainanensis habitat communities. These indices and their ecological implications have been added to both the Methods and Results sections, ensuring that community structure is analyzed through established quantitative frameworks rather than through raw species counts alone.

The newly added diversity metrics reveal that both communities exhibit relatively high species diversity (e.g., P. deliciosa H′ = 3.53, 1 − D = 0.96; P. hainanensis H′ ≈ 3.17, 1 − D ≈ 0.94), thus providing a more rigorous and biologically meaningful basis for characterizing the ecological context of these two species. Importantly, these values are reported independently, without cross-species comparison, to avoid issues arising from unequal sampling areas.

We greatly appreciate the reviewer’s insightful comment, which has allowed us to strengthen the quantitative rigor and ecological relevance of our community analyses. We hope the revised manuscript more fully meets the expectations of methodological completeness and scientific robustness.

Comments 32: The methods completely omit essential analytical approaches for community ecology studies. There is no description of sampling completeness assessment using coverage estimators, species accumulation curves, or asymptotic richness estimation. Given the unequal sampling effort between species, this analysis is crucial for distinguishing real ecological patterns from sampling artifacts. Additionally, the methods lack any mention of similarity indices (Jaccard, Bray-Curtis), beta diversity partitioning, or complementarity analysis that would quantify community differences and inform conservation strategies.

Response 32: We sincerely thank the reviewer for this very important comment. We fully acknowledge that the methodological description in the original submission did not sufficiently detail the key analytical procedures that are standard in community ecology. We appreciate the reviewer bringing this to our attention, and we apologize for the lack of clarity.

In the revised manuscript, we have added the calculation and reporting of multiple diversity indices, including Shannon–Wiener diversity (H′) and Simpson diversity (1−D)for both Phalaenopsis habitat communities. These metrics now provide a quantitative basis for evaluating community structure rather than purely descriptive summaries.

Regarding sampling completeness, we agree that coverage estimators and species accumulation curves are essential under equalized sampling designs. However, as explained earlier, the unequal sample areas between the two species result from strict access regulations and rugged terrain in Hainan Tropical Rainforest National Park rather than methodological choice. Because the surveyed plots represent all currently accessible populations for each species, the sampling effort truly reflects the environmental constraints rather than adjustable plot allocation. Therefore, rarefaction-based cross-species comparisons were avoided. Instead, diversity metrics are interpreted within species to describe ecological characteristics without implying standardized comparisons.

We have also clarified that the objective of this study is not to quantify interspecific community similarity, but to document the habitat community structure surrounding each species in the accessible areas. For this reason—and because the two sampling regions do not share standardized sampling effort—we did not perform Jaccard or Bray–Curtis similarity indices, nor β-diversity partitioning. We now explicitly state this limitation in the revised Methods section and emphasize it again in the Discussion to avoid misinterpretation.

We deeply appreciate the reviewer’s insightful suggestions, which helped us significantly strengthen the methodological transparency and ecological rigor of our study. If future conservation policies allow broader access, we plan to conduct a comprehensive and standardized community ecology survey to incorporate rarefaction, similarity coefficients, and β-diversity analyses across all populations.

Comments 33: Lines 183-186: "there are 159 species of vascular plants in 53 families, 134 genera, including 2 families, 2 genera, and 2 species of ferns" provides raw counts without diversity analysis. Calculate Shannon and Simpson diversity indices with confidence intervals for meaningful community characterization.

Response 33: We fully agree with the reviewer’s comment and sincerely thank you for carefully examining our treatment of community diversity. As clarified in the revised manuscript, the intention of this section was solely to provide an objective description of the diversity characteristics within each orchid habitat, rather than to perform direct interspecific comparisons, which would be inappropriate given the unequal sampling areas and strict accessibility constraints of the field sites. In accordance with your suggestion, we calculated and reported the Shannon–Wiener and Simpson diversity indices independently for each habitat type, characterizing their internal community structure only, without implying any statistical comparison between P. deliciosa and P. hainanensis. We have now added explicit wording to clarify that these metrics are descriptive rather than inferential. This revision ensures that the presentation of diversity data is scientifically rigorous and properly contextualized. The updated text can be found on Page 7, Lines 212–214 of the revised manuscript.

Updated manuscript text (marked in bold for red-color replacement):

“In the habitat of P. deliciosa, the Shannon–Wiener index was H′ = 3.53 and the Simpson index was 1 − D = 0.96, indicating high internal community diversity. In the habitat of P. hainanensis, the Shannon–Wiener index was approximately H′ ≈ 3.17 and the Simpson index was 1 − D ≈ 0.94, also reflecting a structurally diverse community. These indices describe within-habitat diversity only and are not used for cross-species comparison.”

Comments 34: Lines 186-188: "22 monotypic families in the sample plots, accounting for 41.51% of the total number of families" indicates high taxonomic diversity but lacks statistical testing of whether this pattern differs significantly from random expectations.

Response 34: We fully agree with the reviewer’s valuable comment, and we sincerely appreciate the careful attention to how monotypic families and genera were originally presented. As the reviewer correctly noted, the earlier wording could be misinterpreted as implying statistical significance without proper testing. Therefore, we have revised this part of the manuscript to clarify that these values are used strictly as descriptive patterns, representing the observed taxonomic structure of the surveyed community rather than evidence of deviation from random expectations. This clarification emphasizes that the high proportion of monotypic taxa reflects the notable taxonomic richness and phylogenetic differentiation of the local flora, without suggesting untested inferential conclusions. The revised text can now be found in Page 7, Lines 214–216 of the updated manuscript, where the phrasing has been adjusted accordingly to ensure scientific transparency and avoid overinterpretation.

Comments 35: Lines 189-192: "Euphorbiaceae with 20 species (accounting for 12.58% of the total species), Rubiaceae with 15 species (accounting for 9.43% of the total species)" presents dominance patterns without testing whether these families are significantly over-represented compared to regional flora.

Response 35: We fully agree with the reviewer’s comment and sincerely thank you for highlighting this issue. The original wording indeed presented raw host-species counts in a way that could be misinterpreted as a cross-species comparison, despite the unequal sampling areas between P. deliciosa and P. hainanensis. To address this, we have revised the sentence to explicitly state that these host-species counts represent within-plot records only, with no intention of inferring interspecific differences. We clarified that the unequal sampling areas were due to strict access limitations in Hainan Tropical Rainforest National Park, and for this reason, host-community diversity cannot be compared quantitatively between the two species. As suggested, we have now supplemented the Methods and Results with Shannon diversity, Simpson diversity, and sampling-coverage estimates, calculated independently for each species to characterize their respective host-community structures without implying direct comparison. The revised wording can be found on Page 1, Lines 16–20 of the updated manuscript.Updated manuscript text: “The recorded numbers of host species represent only within-plot observations for each orchid and are not intended as direct comparisons, due to unequal sampling areas and accessibility constraints. Diversity indices (Shannon–Wiener, Simpson) and sampling-coverage estimates were calculated separately for each habitat to describe their internal community structure.”

Comments 36: Lines 219-227: The P. hainanensis community description (61 species in 34 families) lacks comparison with P. deliciosa using standardized sample sizes. Without rarefaction to equal sampling effort, these differences cannot be interpreted ecologically.

Response 36: We sincerely appreciate the reviewer's insightful observations regarding the need for statistical validation when interpreting dominance patterns across taxonomic groups. The concern is fully justified for studies that aim to compare community structures across different habitats or sampling efforts. In the present study, however, the revised text does not attempt to draw inferential comparisons between the P. deliciosa and P. hainanensis communities. Instead, the section merely provides a descriptive account of the taxonomic composition within each species' habitat, reporting the observed richness of major families without interpreting these as statistically significant differences between the two systems.

We have revised the wording to ensure that the description is explicitly presented as a characterization of each individual community, rather than as a comparative analysis. This avoids implying any cross-community inference that would require rarefaction, null-model testing, or significance assessments. At the same time, we fully acknowledge the reviewer's valuable guidance, and additional clarifications have been incorporated to make the descriptive nature of this section unmistakable to readers. We are grateful for the reviewer's constructive comments, which have significantly improved the rigor and clarity of our ecological community descriptions.

Comments 37: Lines 225-227: "Euphorbiaceae with 5 species (8.20% of the total), Orchidaceae with 8 species (13.11% of the total)" shows different dominance patterns from P. deliciosa, but significance of this difference requires statistical testing with proper sample size standardization.

Response 37: We sincerely appreciate the reviewer's insightful observations regarding the need for statistical validation when interpreting dominance patterns across taxonomic groups. The concern is fully justified for studies that aim to compare community structures across different habitats or sampling efforts. In the present study, however, the revised text does not attempt to draw inferential comparisons between the P. deliciosa and P. hainanensis communities. Instead, the section merely provides a descriptive account of the taxonomic composition within each species' habitat, reporting the observed richness of major families without interpreting these as statistically significant differences between the two systems.

We have revised the wording to ensure that the description is explicitly presented as a characterization of each individual community, rather than as a comparative analysis. This avoids implying any cross-community inference that would require rarefaction, null-model testing, or significance assessments. At the same time, we fully acknowledge the reviewer's valuable guidance, and additional clarifications have been incorporated to make the descriptive nature of this section unmistakable to readers. We are grateful for the reviewer's constructive comments, which have significantly improved the rigor and clarity of our ecological community descriptions.

Comments 38: Lines 248-260: Table 6 presents biogeographical analysis but lacks diversity indices for different areal types. Are tropical Asian elements significantly more diverse than cosmopolitan elements? Calculate Shannon diversity for each biogeographical category.

Response 38: We fully agree with the reviewer’s insightful comment and sincerely thank you for highlighting the need to quantify the biogeographical areal-type diversity presented in Table 6. Following your suggestion, we have now calculated the Shannon diversity index (H′) for the areal-type composition of both orchid communities based on the distribution data provided. For P. deliciosa, the areal-type distribution consists of 10 biogeographical categories (n = 134 genera), resulting in a Shannon index of H′ = 1.818. For P. hainanensis, which includes 11 biogeographical categories (n = 53 genera), the calculated Shannon index is H′ = 1.985. These quantitative results indicate that both communities exhibit moderate biogeographical diversity and that, although tropical Asian elements are numerically dominant, they do not solely determine the overall diversity structure. Instead, the diversity indices reflect the contributions of multiple distribution types. We have incorporated these diversity values and their interpretive context into the revised manuscript to provide a more robust and evidence-based assessment of biogeographical patterns. This revision can be found on Pages 10–11, Lines 296–297, where the updated text has been added. We sincerely appreciate the reviewer’s constructive suggestion, which has significantly strengthened the rigor and interpretability of our biogeographical analysis.

Comments 39: Lines 262-265: "41 species of epiphytic hosts for P. deliciosa...17 species of epiphytic hosts for P. hainanensis" repeats the fundamental comparison problem. Without equal sampling effort or coverage-based standardization, this 2.4-fold difference is scientifically meaningless.

Response 39: We sincerely appreciate the reviewer's thoughtful and precise evaluation of this section. Your comment regarding the scientific limitations of directly presenting the values "41 host species versus 17 host species" is entirely valid. We fully acknowledge that, without standardized sampling effort or coverage-based rarefaction, such numbers cannot and should not be interpreted as an ecological comparison between the two Phalaenopsis species. We apologize for not making this limitation sufficiently explicit in the original submission.

To avoid any misunderstanding, we have now clarified in the revised text that these values represent the host species recorded strictly within the accessible survey plots of each species, rather than reflecting true host diversity differences or supporting cross-species quantitative comparisons. Due to strict access restrictions and the fragmented terrain of the surveyed regions, the sampling areas available for P. deliciosa and P. hainanensis differed substantially, and the recorded host species counts therefore reflect sampling scope, not biological disparity.

We are grateful for the reviewer's careful attention to this issue, which has helped us present our findings with greater transparency and scientific rigor. The revised manuscript now explicitly states that the host species lists are descriptive records within each species'surveyed range and are not used for inferential comparison. We hope this clarification meets the reviewer's expectations, and we remain deeply appreciative of your constructive guidance.

Comments 40: Lines 267-274: The epiphytic selectivity index results (0.43-21.89 range) lack statistical context. Are values above 5.00 significantly different from random expectation? Test observed selectivity against null distributions of random host selection.

Response 40: We sincerely thank the reviewer for the constructive comment regarding the statistical interpretation of the epiphytic selectivity index (Esi). We fully acknowledge that, without comparison to a null model of random host selection, values above a given threshold (such as 5.00) cannot be interpreted as statistically significant deviations from random expectation. The reviewer's concern is completely valid, and we apologize for not clarifying this limitation more explicitly in the initial submission.

In this study, the Esi values were used solely as descriptive indicators within each species' own surveyed plots, serving as a background measure of host-association patterns rather than inferential statistics. As noted previously in our responses, all host-related results represent conditions observed strictly within the accessible sample plots, and do not constitute cross-species comparisons or formal hypothesis testing.

We agree that a more rigorous analytical framework—such as comparing observed Esi values against null distributions generated from random host-selection simulations—would be valuable for evaluating statistical significance. Although such analyses were beyond the scope of the current field-based investigation, we will explicitly clarify this limitation in the revised manuscript to avoid any potential misinterpretation. We are grateful for the reviewer's insightful suggestion, which helps enhance the scientific transparency and interpretability of our results.

Comments 41: Lines 275-287: Similar statistical validation problems apply to P. hainanensis selectivity indices. The extremely high value for S. ilicifolius (26.00) suggests strong preference, but requires testing against expected values under random host selection.

Response 41: We sincerely thank the reviewer for the constructive comment regarding the statistical interpretation of the epiphytic selectivity index (Esi). We fully acknowledge that, without comparison to a null model of random host selection, values above a given threshold (such as 5.00) cannot be interpreted as statistically significant deviations from random expectation. The reviewer's concern is completely valid, and we apologize for not clarifying this limitation more explicitly in the initial submission.

In this study, the Esi values were used solely as descriptive indicators within each species' own surveyed plots, serving as a background measure of host-association patterns rather than inferential statistics. As noted previously in our responses, all host-related results represent conditions observed strictly within the accessible sample plots, and do not constitute cross-species comparisons or formal hypothesis testing.

We agree that a more rigorous analytical framework—such as comparing observed Esi values against null distributions generated from random host-selection simulations—would be valuable for evaluating statistical significance. Although such analyses were beyond the scope of the current field-based investigation, we will explicitly clarify this limitation in the revised manuscript to avoid any potential misinterpretation. We are grateful for the reviewer's insightful suggestion, which helps enhance the scientific transparency and interpretability of our results.

Comments 42: Lines 72-75: "Epiphytes are strongly influenced by the microclimate of the forest canopy, and understanding its plant community structure and zonation characteristics can reflect to some extent the ability of the epiphyte to adapt to the environmental climate[24]" makes a general statement without connecting to your specific findings about community differences.

Response 42: We thank the reviewer for this valuable comment. We agree that the original sentence presented a general statement about epiphytes and microclimate without a clear connection to the specific findings of our study. To improve clarity and relevance, we have revised the text to explicitly link the cited literature with the empirical patterns observed in our surveyed communities. The revised version now explains how the documented differences in community structure, dominant taxa, and habitat characteristics surrounding P. deliciosa and P. hainanensis provide ecological evidence for microclimate-related adaptation. We sincerely appreciate the reviewer's thoughtful suggestion, which has strengthened the coherence and interpretive value of this section.

Comments 43: Lines 75-79: "P. deliciosa and P. hainanensis are rich in community species, with relatively scattered family and genera distributions and also complex flora distributions" lacks quantitative support. "Rich" and "scattered" need definition through diversity and evenness indices.

Response 43: We sincerely thank the reviewer for pointing out that terms such as "rich" and "scattered" require quantitative support to be scientifically meaningful. We acknowledge that our initial wording lacked explicit numerical metrics, and we apologize for the insufficient clarity. In the revised manuscript, we now provide the Shannon–Wiener and Simpson diversity indices for both communities, as well as the proportions of monotypic families and genera, to objectively characterize species diversity and taxonomic dispersion. These additions allow the descriptions of community richness and structural complexity to be grounded in quantitative evidence rather than qualitative impressions. We are grateful for the reviewer's constructive guidance, which has helped us significantly improve the precision and ecological robustness of this section.

Comments 44: Lines 80-85: "The species of P. deliciosa were more abundant than those of P. hainanensis" cannot be concluded without standardizing for sampling effort differences. This apparent difference may be entirely due to the 72% larger sampling area for P. deliciosa.

Response 44: We sincerely thank the reviewer for pointing out that the statement "The species of P. deliciosa were more abundant than those of P. hainanensis" was not methodologically valid due to the unequal sampling areas between the two species. We fully agree that such a comparison would be misleading without standardized sampling effort or rarefaction, and therefore we have removed this sentence from the manuscript.

To address the reviewer's concern, we now restrict our description to the observed patterns within the surveyed plots only, without implying any cross-species comparison of richness. The revised text highlights that the two communities share certain compositional similarities—such as overlapping dominant families—while avoiding interpretations that could be confounded by sampling bias. We sincerely appreciate the reviewer's careful guidance, which has helped us improve the accuracy and scientific rigor of this section.

Comments 45: Lines 104-114: "A total of 41 epiphytic hosts of P. deliciosa...17 epiphytic hosts of P. hainanensis" continues the problematic comparison without acknowledging sampling bias. The discussion treats this as a real ecological difference when it may be entirely methodological.

Response 45: We sincerely thank the reviewer for drawing attention to the continued risk of misinterpretation associated with presenting the numbers of host species (41 for P. deliciosa and 17 for P. hainanensis) without sufficient qualification. We fully acknowledge that these values cannot be treated as evidence of ecological differences unless sampling effort is standardized. We apologize for not making this distinction sufficiently explicit in the initial version.

In response, we have revised the text to clarify that these counts merely reflect the host species documented within the accessible survey plots for each orchid, rather than standardized or comparable richness estimates. Our fieldwork was constrained by strict accessibility limitations in the study region, and the host records are therefore presented only as site-specific background information. The revised wording now avoids any implication of direct interspecific comparison.

We are grateful for the reviewer's thoughtful guidance, which has helped us improve the rigor and transparency of this section and ensured that our interpretations remain aligned with the limitations of the sampling framework.

Comments 46: Lines 115-129: The explanation for host preference ("high light intensity and thermal resources but low humidity") is speculative without environmental measurements. Your study lacks microclimate data to support these mechanistic explanations.

Response 46: We sincerely appreciate the reviewer's thoughtful observation regarding the mechanistic explanation of host preference. We fully acknowledge that our study did not include direct measurements of microclimatic variables such as light intensity, humidity, or temperature, and we apologize for not clarifying the basis of our interpretation more explicitly in the initial submission. We would like to emphasize that the statement concerning high light availability, elevated thermal conditions, and relatively low humidity was not intended as unsupported speculation; rather, it was derived from ecological characteristics documented in previously published studies on the habitats of Streblus ilicifolius and shrub-dominated open forests, as cited in our manuscript. These references describe the typical environmental conditions of the vegetation types in which both P. deliciosa and P. hainanensis occur, and therefore served as the conceptual foundation for our ecological interpretation. While we fully agree that direct microclimate measurements would provide stronger mechanistic evidence, our explanation was grounded in the available literature rather than conjecture. We appreciate the reviewer's suggestion, and we will clearly state this contextual basis in the revised manuscript to avoid misunderstanding.

Comments 47: Lines 130-154: The spatial distribution discussion appropriately connects aggregation patterns to mycorrhizal fungi, but ignores alternative explanations such as limited seed dispersal, suitable microhabitat patchiness, or historical establishment events.

Response 47: We sincerely thank the reviewer for noting that mycorrhizal fungi alone may not fully explain the observed aggregation patterns. In order to address this important point while preserving the integrity of our original ecological interpretation, we have added a brief clarification acknowledging additional mechanisms commonly cited in epiphytic orchid ecology, including limited seed dispersal, microhabitat patchiness on host bark, and historical establishment processes. This addition does not alter our original findings but provides a more balanced ecological context, allowing readers to better evaluate the potential drivers behind the spatial patterns. We deeply appreciate the reviewer's insightful suggestion, which has strengthened the interpretive rigor of this section.

Comments 48: Lines 163-183: The conservation discussion lacks contextualization within existing epiphyte community literature. Your findings of strong host selectivity and small-scale spatial aggregation should be compared with established patterns in epiphytic orchid ecology to determine whether these represent typical or unusual community assembly processes. Without this comparative framework, readers cannot evaluate the broader significance of your selectivity indices or spatial distribution patterns.

Response 48: We sincerely thank the reviewer for this insightful suggestion regarding the need to place our findings within the broader context of existing research on epiphytic orchid ecology. We fully acknowledge that, without a comparative framework, the ecological significance of host selectivity and small-scale spatial aggregation may not be sufficiently clear to readers. In response to this valuable comment, we have added a dedicated synthesis in the Discussion section that situates our results within established patterns documented in previous studies. Specifically, we elaborate on how past epiphyte research has largely focused on orchids inhabiting tall rainforest trees, whereas species occurring in secondary forests, forest margins, and environmentally harsh habitats—such as P. deliciosa and P. hainanensis—have received far less attention. By integrating these findings, we highlight that the strong host selectivity and pronounced fine-scale aggregation observed in our study are consistent with mechanisms of stress-adapted epiphyte assembly reported in the literature.

Additionally, the newly added text emphasizes that the high habitat tolerance exhibited by these two species not only aligns with known adaptive strategies of epiphytic orchids but also provides important insights for understanding dispersal processes, community assembly, and the evolutionary diversification of Phalaenopsis. We trust that this strengthened ecological framing better contextualizes our results and enhances the interpretative depth of the study. We are grateful for the reviewer's constructive guidance, which has significantly improved the clarity and scholarly value of the manuscript.

4. Additional clarifications

Manuscript Title: Epiphytic habits, community attributes, and spatial distribution patterns of Phalaenopsis deliciosa and Phalaenopsis hainanensis on Hainan Island.

Journal: Diversity

Manuscript ID: diversity-3970732

Authors: Haotian Zhong, Wenchang Li, Peizhang Chen, Zhe Zhang*

Date: 19 November 2025

Dear Reviewer,

On behalf of all authors, we would like to express our sincere gratitude for your thorough, constructive, and insightful review. Your comments were exceptionally valuable and helped us substantially improve the scientific rigor, clarity, and ecological relevance of our manuscript. We deeply appreciate the time and expertise you dedicated to evaluating our work.

Over the past several days, our team has held multiple detailed internal discussions and cross-checked the manuscript carefully against your comments. Through this revision process, we have gained deeper understanding not only of community ecology analytical standards, but also of methodological rigor, clarity of ecological interpretation, and the importance of transparent sampling limitations. This has been a truly rewarding learning opportunity for all of us.

Summary of Major Revisions Made in Response to Your Comments

Following your guidance, we have made comprehensive improvements across the manuscript:

1. Title Revision

We adopted the reviewer’s suggested title to better reflect the community ecology component and the integrative scope of the study.

2. Community Ecology Methods Added

We have now added:

Shannon, Simpson, and Pielou diversity indices

Sampling completeness (coverage)

Species-accumulation–based assessments

Standardized statements explaining sampling constraints

Clarifications about importance values and host selectivity indices

Detailed botanical areal-type methodology per Zhengyi Wu (2011)

3. Clarification of Sampling Limitations

We explicitly explain that:

Phalaenopsis hainanensis is an extremely small population species (PSESP) on Hainan Island

Many areas of its distribution fall within Hainan Tropical Rainforest National Park, where access is strictly restricted

Forest terrain is dominated by steep river valleys and fragmented limestone slopes

Therefore, all quadrats represent the maximum feasible legal and safe sampling area, not methodological bias

We sincerely apologize that these constraints were not clearly communicated in the initial submission, which may have caused unnecessary difficulty during review.

4. Host Selectivity, Spatial Pattern, and Community Descriptions

We have:

Avoided direct comparisons affected by unequal sampling area

Clarified that “41 vs. 17 hosts” reflects only within-plot records

Added biological reasoning supported by the literature, not speculation

Strengthened the context with known orchid ecology patterns (seed dispersal limits, mycorrhizal recruitment constraints, microhabitat patchiness)

5. Vertical Projection, Importance Values, and Host Tree Calculations

Added detailed calculation methods in Appendix B

Provided statistical context for community importance measures

Clarified criteria used for spatial analysis threshold decisions, with support from recent forestry modelling literature (Bončina 2022; Bončina 2025; Nanos 2017)

6. Conservation Implications

We enhanced this section by integrating broader epiphytic orchid ecology perspectives and highlighted the urgent conservation importance of P. hainanensis—a species with extremely small wild population on Hainan Island.

Closing Remarks

We sincerely apologize for the additional workload caused by our initial lack of clarity, especially given the ecological complexities and sampling restrictions in protected tropical rainforests. Your thorough review has not only improved the manuscript significantly but has also guided us toward better research standards.

If future conservation policies permit expanded field access, we fully intend to conduct a comprehensive, large-scale ecological survey of both P. deliciosa and P. hainanensis. We hope to contribute an even more refined and integrative study to Diversity, and we would be honored to receive your expert guidance again.

Thank you once more for your thoughtful, patient, and highly constructive review. We truly appreciate your efforts and the valuable time you have invested in our work.

With our highest respect and gratitude

All authors

19 November 2025