Effects of the Dominate Plant Families on Elevation Gradient Pattern of Community Structure in a Subtropical Forest

Round 1

Reviewer 1 Report

Based on species diversity index, total basal area, and soil factors, generalized additive models (GAM) and regression analysis were used to analyze the impacts of dominate plant taxa on the forest community assembly along the elevational transect. It is of great significance to clarify the corresponding relationship between community structure and altitude gradient in subtropical forest. However, the simple index and lower analysis depth seems that the relevant results can not fully reflect and explain the influence of dominant plants on the evaluation pattern of community structure.

 

1.     There were only Shannon-Weiner index and richness to explain the community structure, without the community dominance index and important values, the important parameters which represent the community structure. Please provide the specific data, including the relevant data of major taxa, different altitude gradients, etc.

2.     Besides the elevation, this MS analyze the soil factors including TK, TN, TP and pH, but lack of the analysis on temperature, soil water, slope, etc. It is difficult to fully illustrate the impact of habitat factors on the community altitude gradient pattern.

3.     The simple and incomplete legends of the charts could not make a clear expression, and usually confusing. e. g. Table 1, Figure 3/4 and Figure S1/S2, “Relationship between Lauraceae, Fagaceae and …………”, “Figure S2 Regression after removal of 700m”,……

4.     What means of Lam in “such as biomass and density (Lam).”，and Pandey in “environmental gradients(Pandey)”？

5.     The whole article does not seem to clearly indicate how or what effects of these dominant plant families have on the elevation gradient pattern of the community structure.

1.     The expressions need to be further improved. e. g. “A total of 25 species of Lauraceae, belonging to 6 genera, and 16 species of Fagaceae, belonging to 3 genera. were found in this survey (Supplementary Table S1).”，“After mixing, 500 g was taken back to the laboratory for analysis by quartering method and 110 soil samples for the study.” , and so on.

2.     To many small mistakes about the spelling of words, and format of fonts, latin names, punctuation, and line numbers. e. g. “the Daming Mountai”, “Therefore Understanding the factors influencing TBA is important for forest management.”, “3.6 Influence of plantl factors”, “(i.e., climate, soil and )”, “Shannon.Wiener”, “Table S1: title; Video S1: title.”, and so on.

Author Response

Response to Reviewer 1 Comments

Point 1 : There were only Shannon-Weiner index and richness to explain the community structure,

without the community dominance index and important values, the important parameters which

represent the community structure. Please provide the specific data, including the relevant data of

major taxa, different altitude gradients, etc.

Response 1: Thank you. We added the Simpson Index to characterize species diversity. We analyzed

the pattern of elevational gradients in the Simpson Index. And we also analyzed the correlation of

Lauraceae and Fagaceae with the Simpson Index. To represent the degree of species dominance, we

calculated the importance value index for each species. Our changes/additions to the manuscript are

given in the blue text.

Point 2: Besides the elevation, this MS analyze the soil factors including TK, TN, TP and pH, but lack

of the analysis on temperature, soil water, slope, etc. It is difficult to fully illustrate the impact of

habitat factors on the community altitude gradient pattern.

Response 2: unfortunately, we did not have data about temperature, soil water . But we have added

the soil organic matter, soil bulk weight and slope in the data analysis.

Point 3: The simple and incomplete legends of the charts could not make a clear expression, and

usually confusing. e. g. Table 1, Figure 3/4 and Figure S1/S2, “Relationship between Lauraceae,

Fagaceae and …………”, “Figure S2 Regression after removal of 700m”,

Response 3: All figures and tables has been revised.

Point 4:What means of Lam in “such as biomass and density (Lam).”，and Pandey in “environmental

gradients(Pandey)”？

Response 4: We have corrected these citation mistakes in the new version.

Point 5:The whole article does not seem to clearly indicate how or what effects of these dominant

plant families have on the elevation gradient pattern of the community structure.

Response 5: We have re-written this part according to the Reviewer’s suggestion.P13, Line9-33, was

added.’ Lauraceae and Fagaceae showed a significant positive correlation with the species diversity.

This may be due to the high diversity of Camphoraceae and Crustacea in the Daming Mountain[55]

and found in the present studyLauraceae and Fagaceae have a very high diversity in the Daming

Mountain National Nature Reserve. A total of 25 species of Lauraceae, belonging to 6 genera, and 16

species of Fagaceae, belonging to 3 genera. were found in this survey (Supplementary Table S1). This

is one of the reasons for the correlation of the Lauraceae and Fagaceae to species diversity. We

analysed the elevational gradient in the abundance of Lauraceae and Fagaceae (Supplementary

Figure S2). Found the same trend as species diversity. This also proves their correlation. This result

may be caused by the high rainfall of the Daming Mountain at mid-elevation. Both Lauraceae and

Fagaceae have high diversity in humid and warm environment. Our result was in line with

Kamimura et al. which showed the number of individuals in Lauraceae was positively correlated

with community richness.[59]. These suggests that species diversity in the Daming Mountain is influ-

enced by the affect Lauraceae and Fagaceae.

Fagaceae is a major contributor to basal area in subtropical forests. This is consistent with our results

(Fig 1C,5). The specific ecological traits that favour adapta-tion to cool montane habitats, the long

evolutionary history may have led to the unique importance in terms of biomass of Fagaceae[61].

Moreover, some Fagaceae species have high seed yields, high germination capacity and fast growth

rates that drives more biomass.’ Our changes/additions to the manuscript are given in the blue text.

 

 

Author Response File: Author Response.docx

Reviewer 2 Report

The subject is interesting (Effects of the dominate plant families on elevation gradient  pattern of community structure in a subtropical forest), but the authors fail to write Ms clearly.  The authors mentioned about tree density, basal area, tree species richness etc. However in the methodology section the information on these are missing. Add a section on which biological indices were used and why. In the discussion section compare your results from the Indian Himalayan also. Why authors have chosen equal number of plots – i.e. 3 - 6 quadrats- in each of altitude. This may lead to under-sampling in many forest types.  Plots with larger area should be sampled more rigorously to address variability. Forest types in terms of altitudinal gradient must be presented in the Map. This would provide a perspective for readers. In addition, what data was used for calculating different diversity indices?   More importantly, the author should recommend the implications of the study to policy maker. However, the data in the manuscript deserve to be published, so I provide some suggestions for what the authors may include in the manuscript that could be published, for example, in this journal.

 

Comments for author File: Comments.pdf

 

The subject is interesting (Response of aboveground net primary production, species and  phylogenetic diversity to warming and increased precipitation in an alpine meadow), but the authors fail to write Ms clearly.  Particularly, the method section requires a lot of improvement, for example, how the coverage and height of plants was calculate. In addition, the authors must mention the study design whether it is experimental study or field based. In the result, section authors must provide the plant list and highlight different types of plant communities. In addition, what data was used for calculating different diversity indices? The authors mentioned couple of things in results section like species richness, species composition, phylogenetic composition   but nowhere in the methods sections these parameters are present.. what data was used..how you identify species..  The author fails to clarify the data analysis methodologies about how Venn diagram were prepared, software used etc. More importantly, the author should recommend the implications of the study to policy makers; otherwise, it seems like hypothetical study without field based utility. However, the data in the manuscript deserve to be published, so I provide some suggestions for what the authors may include in the manuscript that could be published, for example, in this journal.

Author Response

Response to Reviewer 2 Comments

 

Point 1 : The subject is interesting (Effects of the dominate plant families on elevation gradient  pattern of community structure in a subtropical forest), but the authors fail to write Ms clearly.  The authors mentioned about tree density, basal area, tree species richness etc. However in the methodology section the information on these are missing. Add a section on which biological indices were used and why. In the discussion section compare your results from the Indian Himalayan also. Why authors have chosen equal number of plots – i.e. 3 - 6 quadrats- in each of altitude. This may lead to under-sampling in many forest types.  Plots with larger area should be sampled more rigorously to address variability. Forest types in terms of altitudinal gradient must be presented in the Map. This would provide a perspective for readers. In addition, what data was used for calculating different diversity indices?   More importantly, the author should recommend the implications of the study to policy maker. However, the data in the manuscript deserve to be published, so I provide some suggestions for what the authors may include in the manuscript that could be published, for example, in this journal.

Response 1: Thank you. We have listed point by point response below. And we list the changes and marked in blue.

1. We have revised the methods section. In the new manuscript, I describe more fully how the survey was conducted. To calculate the biodiversity index of the community, we used the Shannon-Wiener Index with the Simpson Index. To analyze the dominance of species, we integrated data from 22 plots to calculate the importance value index of each species. We illustrate the forest type for each sample plot in Table1. All indices and formulas in this article are listed in Supplementary Table S2.
2. We quoted 'https://doi.org/10.1016/j.foreco.2021.119968 ' in the discussion section.(Page 13 Line300 ).
3. We ensured a minimum of 3 plots at each elevation in order to satisfy repeatability. Each forest type is also guaranteed to have 3 or more sample plots. Topographic map was produced to show the location of the sample plots.
4. All indices and formulas in this article are listed in Supplementary Table S2.
5. In order to recommend the implications of the study to policy maker, we reviewed the literature on the significance of protecting important species. We likewise respond to your suggestions on a case-by-case basis. Please see the latest file. Our changes/additions to the manuscript are given in the blue text.

 

Author Response File: Author Response.docx

Reviewer 3 Report

The manuscript is mainly descriptive and reproduces some patterns already registered in the literature, whereas the details are of more regional interest. However, since the reserve appears to have a large local and regional importance, as well as a high plant diversity, these descriptions should be published. The main points that the authors should consider in modifying the manuscript are given below.

Throughout the entire manuscript there are several (many) typing errors, therefore a thorough review is extremely important. I highlight some of these errors in the text, but there are many others.

The item study area lacks information on rainfall seasonality, and whether there are wet and dry seasons.

The results regarding soil attributes are confusing. As the authors do not present summary statistics such as averages and ranges of sampled soil attributes, it is very difficult for the reader to understand the correlation between nitrogen and plant species diversity, and the (absence of) correlations between phosphorus and potassium with plant species richness and diversity. This is extremely important as soil attributes vary seasonally in many forest ecosystems. Furthermore, in the discussion the authors mention the negative influence of aluminum on plant productivity in soils with pH > 9.0, but in the description of the study area the authors state that pH values vary between 3.9 and 4.7, therefore well below from 9.0. It would be more elucidative if soil data were presented along the altitudinal gradient in table or graph form. However, to maintain soil results, authors must clearly describe the time of year this soil was sampled and whether the soil was sampled at different times at different altitudes (in this case, these effects are confounded).

The conclusion must be completely rewritten. In the attached text to the authors there are several points that could help them.

Comments for author File: Comments.pdf

No comments

Author Response

Response to Reviewer 3 Comments

 

Point 1 : The manuscript is mainly descriptive and reproduces some patterns already registered in the literature, whereas the details are of more regional interest. However, since the reserve appears to have a large local and regional importance, as well as a high plant diversity, these descriptions should be published. The main points that the authors should consider in modifying the manuscript are given below.

 

Throughout the entire manuscript there are several (many) typing errors, therefore a thorough review is extremely important. I highlight some of these errors in the text, but there are many others.

 

The item study area lacks information on rainfall seasonality, and whether there are wet and dry seasons.

 

The results regarding soil attributes are confusing. As the authors do not present summary statistics such as averages and ranges of sampled soil attributes, it is very difficult for the reader to understand the correlation between nitrogen and plant species diversity, and the (absence of) correlations between phosphorus and potassium with plant species richness and diversity. This is extremely important as soil attributes vary seasonally in many forest ecosystems. Furthermore, in the discussion the authors mention the negative influence of aluminum on plant productivity in soils with pH > 9.0, but in the description of the study area the authors state that pH values vary between 3.9 and 4.7, therefore well below from 9.0. It would be more elucidative if soil data were presented along the altitudinal gradient in table or graph form. However, to maintain soil results, authors must clearly describe the time of year this soil was sampled and whether the soil was sampled at different times at different altitudes (in this case, these effects are confounded).

 

The conclusion must be completely rewritten. In the attached text to the authors there are several points that could help them.

Response 1: Thank you.

We've reviewed the article more thoroughly and made changes to the errors. We really hope that the flow and language level have been substantially improved.

  We provided the intra-annual variation of rainfall in the methods part. (Page 3, Lines 20-23).‘The distribution of precipitation varies considerably, with June~August accounting for 45.3%~47.5% of annual rainfall, March~May for 23.1%~25.8%, September~November for 14.7%~20.1%, and December-February for 8.4%~10.7%.’

We have conducted new data analysis. We plotted the change of soil factor with elevation. Please see Supplementary Figure S2. We collected soil samples in August 2017 (same time as the species survey). In August 2017,we collected soil samples at a depth of 0~20 cm at five randomly se-lected points in each 20*20 m plot and thoroughly mixed the samples to analysis. At the same time, we removed ‘the negative influence of aluminum on plant productivity in soils with pH > 9.0’. We think it will confuse the reader.

 We have rewrite the conclusion as’ The Lauraceae and Fagaceae make great economic and ecological value to the people.However, few studies have analyzed in detail the contribution of these two families to subtropical forests. Our results indicate Lauraceae and Fagaceae are key taxa that drive species diversity and total basal area of the plant community. Moreover, Fagaceae has played more important role than Lauranceae. Our study however, is lack of the mechanisms, which still need to be explored. It is of great significance to study the dynamics of dominant plant families for forest management and community conservation.’ . (Page 14, Lines 1-7)

 

 

Author Response File: Author Response.pdf

Reviewer 4 Report

The manuscript has sufficient statistical support to communicate results with clear and concise interpretations; additionally, in the discussion section there are relevant elements and significant contributions for a better understanding of the study. The findings are clear and provide convincing results with precise numbers for the understanding of readers and managers of forest ecosystems.

Finally, on page three in the penultimate line supplement the word phosphorus, because it is incomplete.

Author Response

Response 1: Thank you. We have modified this word on page 5, Line 10.

Author Response File: Author Response.docx

Round 2

Reviewer 1 Report

he authors have provided detailed supplementary information regarding experimental design and data statistics, accompanied by relevant data to robustly support their research conclusions. I believe I have no further comments. However, there is a need for more meticulous checking and revision in terms of English formatting and other details.

 

Details on format, terminology and words spelling need a totoally checking and  revising.

For example: 

1. Line 110-120, the intoduction of Daming Moutian should be briefly;

2. Line 129, the latin name of species need italic, the same goes for the other species and genus;

3. Line 144, "(DBH) than or equal to 1.",  there need a unit at the end;

4. Figure 2 was not in a normal shape;

5. A blank spce is needed between the number and parenthesis or equal sign, et al.

Author Response

We thank the reviewer for the thoughtful review and comments on our study.

1.Line 108-124, we have a more concise introduction to Daming Moutian.'

The Guangxi Daming Mountain Nature Reserve (23°24' to 23°30' N, 108°20' to 108°34' E) is located in the south central part of Guangxi. It is a national level nature reserve with typical zonality, characterized by protecting the subtropical mountain forest ecosystem and cherishing endangered flora and fauna. The Daming Mountain belongs to the southern subtropical monsoon climate zone, with an elevation of 115 m to 1760 m and an average elevation of 1200 m. The average annual temperature was 15.1 °C, the hottest temperature was 21.9 °C and the coldest temperature was 5.8 °C, and the average annual rainfall was 2630 mm. The distribution of precipitation varies considerably, with June~August accounting for 45.3%~47.5% of annual rainfall, March~May for 23.1%~25.8%, Septem-ber~November for 14.7%~20.1%, and December-February for 8.4%~10.7%. Soil texture was mainly clay loam and loamy clay with the pH value in the 3.9–4.7 [43]. The main components of each forest vegetation type in Daming Mountain are those in the Lauraceae and Fagaceae, with warmth-loving species dominating the tree layer at low elevation, such as many kinds of Litsea elongata, Castanopsis hystrix, and Machilus decursinervis, etc. As the altitude increases, other constituents in the Lauraceae and Fagaceae gradually increase, as well as those in the Theaceae, Hamamelidaceae, Aquifoliaceae, Symplocaceae, and Magnoliaceae.'

2.We've changed the Latin name in line 129.We also checked the full text for Latin names.

3.We added the unit 'm' to this line.

4.We have redrawn Figure 2

5.We have checked and modified this

 

Reviewer 2 Report

I congratulate the authors on the amount of work put into the study.  The data in the manuscript deserve publication in current form.

I congratulate the authors on the amount of work put into the study.  The data in the manuscript deserve publication in current form.

Author Response

We thank the reviewer for the thoughtful review and comments on our study.