Wildfires and Palm Species Response in a Terra Firme Amazonian Social Forest

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

The manuscript conducts a factorial design on palm composition, dynamics, and litter flammability across four types of habitats in a forest disturbed by fires in eastern Amazon. The authors present the study with the key findings from one-way ANOVA and supporting references for the results. However, more details of the forest, more explanation for their research design, and more related discussion on their conclusion should be included.

The authors should provide details of the original community structure and homogeneity of fire regime to support their conclusion. The authors also need to describe the interaction between villages and forest plots. Are there any differences in such an interaction?

Second, the number of plots surveyed is small. For burned plots (either once or twice), only 7 were surveyed. The authors should justify the limited sample size in this study.

In addition, the authors refer to some literature supporting their findings in Discussion. However, are there other factors that may lead to the findings of this study, e.g., environmental and geographic variation?

Below are comments on the details of figures and methods, which should be improved in revision.

Figure 1: The legend can be divided into three panels instead. Now the green area in panel b is not mentioned in the legend. Also, the symbol of local villages should be center of local villages. Scales for panels a and b are missing.

Methods 2.2 (Line 150): Can the authors decribe the two accidental fires?

Figure 2b: It is questionable to find the number of species to be decimal numbers (e.g., 4.1, 6.1). Can the authors check and reproduce this panel?

Figures 4 and 5 can be one figure. The figure caption misses the definition for Curua, which is the second column in the figure panels. Or the authors can use a table to summarize the results shown in Figures 4 and 5.

Comments on the Quality of English Language

The sentence (Lines 20-26) in Abstract is too long. The attributive clause should be rewritten to avoid extremely long sentence in Abstract.

Lines 30-31: Only the abundance of Attalea spectabilis Mart. (curuá) increased.

Line 35: five-to-ten-fold

Line 36: lower carbon but higher volatile content

Line 38: () should be listed in Line 27, or keep it in the main text.

Line 41: forest resilience and social production

The authors frequently use "traditional" (e.g., Line 23, 105) and similar adjectives to emphasize the scientific soundness of the study areas and palm communities. The authors can describe these details instead.

The authors sometimes repeat the same expressions as those just mentioned in the previous lines (e.g., Lines 317 and 323: we refer to). The authors can rephrase these expressions, reduce redundancy and improve readability of the text.

Author Response

RESPONSES TO REFERRES

 

Revisor 1

Comments and Suggestions for Authors

 

The manuscript conducts a factorial design on palm composition, dynamics, and litter flammability across four types of habitats in a forest disturbed by fires in eastern Amazon. The authors present the study with the key findings from one-way ANOVA and supporting references for the results. However, more details of the forest, more explanation for their research design, and more related discussion on their conclusion should be included.

The authors should provide details of the original community structure and homogeneity of fire regime to support their conclusion. The authors also need to describe the interaction between villages and forest plots. Are there any differences in such an interaction?

R: Done. Information has been added to topic 2.2. Forest habitats.

 

Second, the number of plots surveyed is small. For burned plots (either once or twice), only 7 were surveyed. The authors should justify the limited sample size in this study.

R: Done. Information has been added to topic 2.2. Forest habitats.

 

In addition, the authors refer to some literature supporting their findings in Discussion. However, are there other factors that may lead to the findings of this study, e.g., environmental and geographic variation?

R: Our entire discussion was based on findings and literature support. No measurements of environmental or geographic variation were taken.

 

Below are comments on the details of figures and methods, which should be improved in revision.

Figure 1: The legend can be divided into three panels instead. Now the green area in panel b is not mentioned in the legend. Also, the symbol of local villages should be center of local villages. Scales for panels a and b are missing.

R: Done.

 

Methods 2.2 (Line 150): Can the authors decribe the two accidental fires?

R: Done. Information has been added to topic 2.2. Forest habitats.

 

Figure 2b: It is questionable to find the number of species to be decimal numbers (e.g., 4.1, 6.1). Can the authors check and reproduce this panel?

R: I believe there was a little confusion because the y-axis is formed from integer values.

 

Figures 4 and 5 can be one figure. The figure caption misses the definition for Curua, which is the second column in the figure panels. Or the authors can use a table to summarize the results shown in Figures 4 and 5.

R: Done

 

Comments on the Quality of English Language

The sentence (Lines 20-26) in Abstract is too long. The attributive clause should be rewritten to avoid extremely long sentence in Abstract.

R: Done

 

Lines 30-31: Only the abundance of Attalea spectabilis Mart. (curuá) increased.

R: Done

 

Line 35: five-to-ten-fold

R: Done

 

Line 36: lower carbon but higher volatile content

R: Done

 

Line 38: () should be listed in Line 27, or keep it in the main text.

R: Done

 

Line 41: forest resilience and social production

R: Done

 

The authors frequently use "traditional" (e.g., Line 23, 105) and similar adjectives to emphasize the scientific soundness of the study areas and palm communities. The authors can describe these details instead.

R: Done

 

The authors sometimes repeat the same expressions as those just mentioned in the previous lines (e.g., Lines 317 and 323: we refer to). The authors can rephrase these expressions, reduce redundancy and improve readability of the text.

R: Done

Reviewer 2 Report

Comments and Suggestions for Authors

The study tackles an important and timely question: how terra-firme “social forests” in the eastern Amazon respond to repeated anthropogenic fires, with particular attention to the demographic behaviour of Attalea spectabilis and its potential feedback to flammability. The data set is original, the sampling effort is substantial, and the topic is squarely within the scope of Forests. Nevertheless, before the work can be considered for publication it requires considerable revision to meet the journal’s standards for clarity, methodological transparency, analytical rigour and concision. The issues outlined below should be addressed in a comprehensive revision.

• Title and abstract

The present title is informative but slightly broad; consider whether explicitly signalling the focal species would sharpen readers’ expectations. More critical is the abstract, which compresses too many numeric details into very long sentences and leaves the reader searching for the central take-home message. A rewritten abstract should open with the objective, provide a brief but explicit description of the experimental design, highlight one or two headline results, and end with a concise statement of their ecological implication. In its current form the abstract also reproduces methodological detail (plot size, number of plots) that belongs in the Methods section and uses undefined jargon such as “social forest”.

• Introduction

The Introduction offers a rich literature overview but suffers from meandering prose and occasional redundancy. Several sentences are syntactically convoluted, for example the clause beginning “Whatever the transition the remaining tropical forests are experiencing…”. The narrative would benefit from a clearer funnel: begin with the general problem of fire-mediated forest transitions, narrow to palms as functional indicators, and finish with two or three sharply formulated hypotheses. Doing so will help the reader see why A. spectabilis is the predicted “winner” while A. maripa might be a “loser”.

• Materials and methods

Although most methodological elements are present, they appear in an order that obscures the study logic. Plot allocation across four habitat classes is only clear after careful reading; a simple schematic or tabulated summary would solve this issue. In addition, the description of the flammability trials reads like a laboratory protocol rather than a scientific method section and would be clearer if condensed to its essential variables (sample size, oven-drying temperature, ignition procedure, response variables). The statistical paragraph lists the tests used but does not explain how model assumptions were checked nor the criteria for selecting parametric versus non-parametric approaches; this information must be included so that analyses can be reproduced.

• Results

The results are statistically sound but not always presented in a reader-friendly way. Many sentences repeat the contents of Figures 2–5 instead of interpreting them. A table summarising abundance changes for all ten recorded species would add context to the strong emphasis placed on A. spectabilis. Moreover, certain numeric claims would be clearer if given with confidence intervals rather than ± standard deviations, and if sample sizes were stated explicitly when subsampling occurred (e.g., leaf-litter chemistry).

• Discussion

The Discussion successfully links local patterns to the broader “winner–loser” framework yet becomes prolix and occasionally speculative. Assertions that curuá litter creates a positive fire feedback are plausible but need to be framed as an inference, not a demonstrated mechanism, given that the study measured flammability properties under laboratory rather than field conditions . Several sections reiterate background information already covered in the Introduction or Results. Tightening the prose and grouping ideas thematically, first ecological implications, then management implications, would greatly improve readability.

• Figures and tables

Graphs are generally informative, but axis ranges and panel labelling need harmonisation. Figure captions should describe the graphic elements succinctly and avoid repeating full statistical outputs already stated in the text. Consider adding a concise table of species-by-habitat abundance to complement Figure 2, and move detailed numeric outputs now embedded in the text to supplementary material.

In its present form the manuscript offers valuable data and insight but requires major revisions in writing clarity, presentation of methods and results, and sharpening of the argumentation in the Discussion. I encourage the authors to undertake a thorough restructuring and copy-editing pass; once these issues are addressed, the study could make a significant contribution to our understanding of fire-driven transitions in Amazonian forest landscapes.

 

Comments on the Quality of English Language

Throughout the manuscript, sentence length and grammatical inconsistency hinder comprehension. A professional language edit is strongly recommended. Consistency in terminology, “social forest,” “successional mosaic,” and “vegetation mosaic” are presently used interchangeably, will also help readers follow the narrative.

Author Response

Revisor 2

Comments and Suggestions for Authors

The study tackles an important and timely question: how terra-firme “social forests” in the eastern Amazon respond to repeated anthropogenic fires, with particular attention to 4 the demographic behaviour of Attalea spectabilis and its potential feedback to flammability. The data set is original, the sampling effort is substantial, and the topic is squarely within the scope of Forests. Nevertheless, before the work can be considered for publication it requires considerable revision to meet the journal’s standards for clarity, methodological transparency, analytical rigour and concision. The issues outlined below should be addressed in a comprehensive revision.

 

Title and abstract

 

The present title is informative but slightly broad; consider whether explicitly signalling the focal species would sharpen readers’ expectations. More critical is the abstract, which compresses too many numeric details into very long sentences and leaves the reader searching for the central take-home message. A rewritten abstract should open with the objective, provide a brief but explicit description of the experimental design, highlight one or two headline results, and end with a concise statement of their ecological implication. In its current form the abstract also reproduces methodological detail (plot size, number of plots) that belongs in the Methods section and uses undefined jargon such as “social forest”.

 

Introduction

 

The Introduction offers a rich literature overview but suffers from meandering prose and occasional redundancy. Several sentences are syntactically convoluted, for example the clause beginning “Whatever the transition the remaining tropical forests are experiencing…”. The narrative would benefit from a clearer funnel: begin with the general problem of fire-mediated forest transitions, narrow to palms as functional indicators, and finish with two or three sharply formulated hypotheses. Doing so will help the reader see why A. spectabilis is the predicted “winner” while A. maripa might be a “loser”.

 

Materials and methods

 

Although most methodological elements are present, they appear in an order that obscures the study logic. Plot allocation across four habitat classes is only clear after careful reading; a simple schematic or tabulated summary would solve this issue. In addition, the description of the flammability trials reads like a laboratory protocol rather than a scientific method section and would be clearer if condensed to its essential variables (sample size, oven-drying temperature, ignition procedure, response variables). The statistical paragraph lists the tests used but does not explain how model assumptions were checked nor the criteria for selecting parametric versus non-parametric approaches; this information must be included so that analyses can be reproduced.

 

Results

 

The results are statistically sound but not always presented in a reader-friendly way. Many sentences repeat the contents of Figures 2–5 instead of interpreting them. A table summarising abundance changes for all ten recorded species would add context to the 5 strong emphasis placed on A. spectabilis. Moreover, certain numeric claims would be clearer if given with confidence intervals rather than ± standard deviations, and if sample sizes were stated explicitly when subsampling occurred (e.g., leaf-litter chemistry).

 

Discussion

 

The Discussion successfully links local patterns to the broader “winner–loser” framework yet becomes prolix and occasionally speculative. Assertions that curuá litter creates a positive fire feedback are plausible but need to be framed as an inference, not a demonstrated mechanism, given that the study measured flammability properties under laboratory rather than field conditions . Several sections reiterate background information already covered in the Introduction or Results. Tightening the prose and grouping ideas thematically, first ecological implications, then management implications, would greatly improve readability.

 

Figures and tables

 

Graphs are generally informative, but axis ranges and panel labelling need harmonisation. Figure captions should describe the graphic elements succinctly and avoid repeating full statistical outputs already stated in the text. Consider adding a concise table of species-by-habitat abundance to complement Figure 2, and move detailed numeric outputs now embedded in the text to supplementary material.

In its present form the manuscript offers valuable data and insight but requires major revisions in writing clarity, presentation of methods and results, and sharpening of the argumentation in the Discussion. I encourage the authors to undertake a thorough restructuring and copy-editing pass; once these issues are addressed, the study could make a significant contribution to our understanding of fire-driven transitions in Amazonian forest landscapes.

Comments on the Quality of English Language

Throughout the manuscript, sentence length and grammatical inconsistency hinder comprehension. A professional language edit is strongly recommended. Consistency in terminology, “social forest,” “successional mosaic,” and “vegetation mosaic” are presently used interchangeably, will also help readers follow the narrative.

 

R: Regarding Reviewer 2's points, all points were met. Including English review.

Reviewer 3 Report

Comments and Suggestions for Authors

The manuscript “Social forests, wildfires and palm species response in a terra firme Amazonian forest” focuses on the response of palm species to old-growth forest conversion to successional mosaics due to disturbances, including wildfires. A total of 10 palm species were studied in the eastern Amazon region. Tropical forests play significant role in global climate and biodiversity. The relevance of this study is unquestionable. The novelty is well defined. The study is presented in a well-structured manner. At the same time, I have the following comments:

1) How was the leaf-litter biomass per unit area determined? Add this information and provide results.

2) Line 172. Why were these temperature and duration chosen? How does this corresponds to the temperatures reached on the litter surface during fires that occur in tropical forests? Provide references. What factors influence the volatile content (mass loss)? Discuss this question. Provide results of the volatile matter content (%) and ash content (%).

3) Line 180. It is incorrect to use "Fixed Carbon Content" since the carbon content in charred samples were not actually measured with an elemental analyzer.

4) Line 394 The calorific value of the samples was not determined in this work and therefore cannot be discussed.

Author Response

Revisor 3

Comments and Suggestions for Authors

 

The manuscript “Social forests, wildfires and palm species response in a terra firme Amazonian forest” focuses on the response of palm species to old-growth forest conversion to successional mosaics due to disturbances, including wildfires. A total of 10 palm species were studied in the eastern Amazon region. Tropical forests play significant role in global climate and biodiversity. The relevance of this study is unquestionable. The novelty is well defined. The study is presented in a well-structured manner. At the same time, I have the following comments:

1) How was the leaf-litter biomass per unit area determined? Add this information and provide results.

R: Done.

 

2) Line 172. Why were these temperature and duration chosen? How does this corresponds to the temperatures reached on the litter surface during fires that occur in tropical forests? Provide references. What factors influence the volatile content (mass loss)? Discuss this question. Provide results of the volatile matter content (%) and ash content (%).

R: We appreciate the reviewer’s observation. The temperatures and durations followed the ABNT NBR 8112 standard [37], commonly used for biomass characterization, ensuring complete thermal decomposition under controlled conditions (Agbeshie et al., 2022). While these values exceed natural fire temperatures, studies show that litter surface temperatures in tropical wildfires can reach 343–566 °C, occasionally exceeding 700 °C depending on fuel load (Mondal & Sukumar, 2014; Cavaleri et al., 2024). Volatile content is influenced by moisture, extractives, and structural compounds. We have added this discussion, as well as the results for volatile matter (%) and ash content (%) in the revised manuscript.

 

3) Line 180. It is incorrect to use "Fixed Carbon Content" since the carbon content in charred samples were not actually measured with an elemental analyzer.

R: We acknowledge the reviewer’s concern. However, the term “fixed carbon content” is used in accordance with standard proximate analysis procedures, specifically following the ABNT NBR 8112, which is functionally equivalent to ASTM D1762-84. These standards define fixed carbon content indirectly, by subtracting the sum of moisture, volatile matter, and ash contents from 100%. Although we did not perform elemental carbon analysis using a CHNS analyzer, the terminology is widely accepted in the literature (including Forests journal) for materials analyzed by this method (e.g., Dias Júnior et al., 2020; Bianchini et al., 2025). The term “Fixed Carbon Content” is defined as “the residual fraction of solid fuel that remains after all volatile matter and moisture have been removed during heating under anaerobic conditions, excluding ash. It represents the portion of carbon that contributes to prolonged combustion and heat generation in biomass energy systems [16]. This component is essential for evaluating the energy yield of a fuel, as it indicates the amount of energy stored in solid form that can be released during combustion” (Bianchini, L.; Colantoni, A.; Venanzi, R.; Cozzolino, L.; Picchio, R. Physicochemical Properties of Forest Wood Biomass for Bioenergy Application: A Review. Forests 2025, 16, 702. https://doi.org/10.3390/f16040702). Therefore, the expression remains technically accurate within the scope of proximate/immediate analysis.

 

4) Line 394 The calorific value of the samples was not determined in this work and therefore cannot be discussed.

R: We have removed references to calorific value from the manuscript, as this variable was not directly measured. Our discussion now focuses solely on directly measured parameters (volatile content, ash, and burning behavior) and their implications for fire susceptibility.

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

Dear Authors,

Thank you for the intensive revision. The quality of this manuscript has been greatly improved. There are four minor issues to be addressed by the authors.

Lines 194-195: Can the authors elaborate the interesting fire effects instead of just mentioning them?

Line 275: Why did the number of total stems change in the revision from 2517 to 2179? Did this change affect the results completely? (Do not need to revise the manuscript but please respond to the editor)

Line 311: CF x OGF = 0.05. Is it < 0.05 or > 0.05, which is very important to interpret the result.

Line 413: What are the control sites? I suppose that the authors mean old-growth forest plots?

Author Response

Thank you for the intensive revision. The quality of this manuscript has been greatly improved. There are four minor issues to be addressed by the authors.

1. Thank you.

 

Lines 194-195: Can the authors elaborate the interesting fire effects instead of just mentioning them?

161. Done. Now is “Although the number of plots would be considered limited, interesting fire effects have already been reported, as wildfires affected forest structure, species diversity, and composition [33], in addition to the soil seed bank, which after the fire showed an increase in the number of herbs and short-life cycle pioneer species [32]”. Lines 157-161.

 

Line 275: Why did the number of total stems change in the revision from 2517 to 2179? Did this change affect the results completely? (Do not need to revise the manuscript but please respond to the editor).

1. It was just a wrong sum. We apologize.

 

Line 311: CF x OGF = 0.05. Is it < 0.05 or > 0.05, which is very important to interpret the result.

1. CF x OGF = 0.053, then it is > 0.05.

 

Line 413: What are the control sites? I suppose that the authors mean old-growth forest plots?

31. Yes, are old-growth forest plots. Now is “In this context, A. spectabilis contributes with substantial amounts of fine and combustible material through leaf fall and litter accumulation in palm rosettes, with leaf litter exhibiting the highest volatile matter content among all habitat types, as well as a significantly lower fixed carbon concentration compared to litter from our control sites or old-growth forest sites.” Lines 311-31.

Reviewer 3 Report

Comments and Suggestions for Authors

no comments

Author Response

Thank you for your contribution.