Wealth and Altitude Explain Urban Plant Diversity in Residential Areas of Hainan, China

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

The study focuses on urban plant variety, specifically in residential areas of Hainan Island, China, which has a unique tropical environment. It also used advanced statistical approaches (GLM, PCA, and PCoA) to deliver comprehensive data.

The "luxury effect" concept seems interesting; however, there is minimal engagement with contrasting perspectives or criticisms of the idea. 

Discuss how sampling locations were chosen in the methodology to mitigate potential biases.

Socioeconomic variables such as the "normalized difference vegetation index" are listed but not adequately explained.

Housing prices mention that housing price variability influences plant diversity, but this connection has not been explained. Citing existing similar studies might overcome this issue. 

In Figure 4, PCA is mentioned without detailing its outputs. It needs an additional paragraph to clarify its findings. 

Author Response

Please see the attachment.

Author Response File: Author Response.doc

Reviewer 2 Report

Comments and Suggestions for Authors

Dear Authors,

 

The paper is both interesting and very well written, highly detailed, offering a significant contribution to the study of urban environments and landscape ecology. Its comprehensive analysis of the factors influencing plant diversity in residential areas of Hainan Island sheds light on the complex interplay between socioeconomic variables, environmental gradients, and biodiversity. The integration of both horizontal and vertical gradients in the study provides a unique perspective and highlights the importance of understanding urban ecological dynamics in the context of rapid urbanization and economic development. I do not have many specific comments and my comments are merely suggestions.

I suggest that the sampling sites in Figure 1 be marked with a more contrasting color, as the current use of white is not sufficiently visible against the background. It is unclear why the elevation legend includes a value of -40. Does this refer to the depth of the surrounding sea? If it is not directly relevant to the study, it would be more logical for the lower limit of the elevation range to be set at 0. Clarifying this would enhance the figure's clarity.

Sampling protocol lines 127 -145. The use of purposive sampling is justified given the constraints; however, the authors should provide a more detailed explanation (one or two sentences) why in some areas they have one sampling spot and in others several.

Line 266-274 The use of the GLM model for analysis is well justified, but the model shows a poor fit (Adjusted R² = 0.18). The authors could consider exploring additional statistical models to improve the robustness of their analysis or provide a more detailed justification for retaining the GLM despite its limited performance. Did you try Random Forest or Gradient Boosting Models (GBM)or Structural Equation Modeling (SEM)?

Table 2 needs to be better organized and technically refined, as its current format is very difficult to read. To improve its clarity and usability I suggest using colors. For example you can introduce subtle color coding to differentiate between various categories, or reduce font size or you can replace repeated text with easily recognizable symbols explained in a legend below the table.

Figure 4. Improve resolution of the figure.

Best regards

Author Response

Please see the attachment.

Author Response File: Author Response.doc

Reviewer 3 Report

Comments and Suggestions for Authors

This manuscript investigates the drivers of plant diversity in residential areas, with a well-designed experimental approach and clear data processing procedures. Below are specific comments and suggestions for improvement:

Line 35: The keywords “Biodiversity” and “Socioeconomics” are broad terms that do not clearly reflect the specific focus of the paper. Narrowing down the scope of the keywords will improve the paper’s discoverability by readers.

Line 50: The terms “Biodiversity” and “Plant Diversity” refer to different concepts. The authors should concentrate on "Plant Diversity” as the core and provide a more detailed discussion on the impacts of urbanization on plant diversity.

Line 184: The influence factors of HOP involve many aspects, and there is strong collinearity between HOP and other variables. The authors needs to specify the reason for introducing the variable HOP, especially when the analysis results show that HOP is an important influencing factor, and the relationship between HOP and other variables should be elaborated.

Table 2: It is recommended to redesign the table to enhance clarity, ensuring each row is easily readable. Additionally, line wrapping of single words should be avoided.

Figure 3: If the figure is marking significant differences within groups, it would be helpful to use lines to connect the two subgroups. Furthermore, to maintain consistency with the other groups, the two subgroups within the “Village” category should be displayed using the same color.

Figure 7: The legend is incomplete and requires adjustment for better readability. Additionally, the lack of noticeable differences within subgroups may result from excessive variability in individual groups. The authors should consider redesigning the figure.

Line 347: This paragraph would be more appropriately placed in the discussion section.

Figure 3: This figure does not appear to be cited in the main text. It is suggested to reference it in section “2.2”.

Line 592: This paragraph is misplaced in section 4.3. It is recommended to move it to a more suitable section or to create a new subsection where it fits the context more logically.

Author Response

Please see the attachment.

Author Response File: Author Response.doc

Round 2

Reviewer 3 Report

Comments and Suggestions for Authors

All my previous concerns have been fully addressed, and this study now provides a clear and meaningful contribution to the field.