Topographic Factors Drive Short-Term Understory Revegetation in Burned Areas

Round 1

Reviewer 1 Report

Zhixue He, Lei Wang, Jun Luo, Bin Zhang, Qingchun Deng, Hui Liu

„Topographic factors drive natural understory revegetation in burned areas”

Review

Brief summary:

The study by He et al. provides a valuable contribution to the existing knowledge of post-fire vegetation dynamics as it presents new empirical data from subtropical forests of southwest China. In that respect it definitely contributes to the understanding of fire ecology of the region, which may aid local land management and nature conservation. Furthermore, since fire regimes are rapidly changing all over the world, expanding the current knowledge of fire effects on ecosystems with data from different geographical locations seems relevant. Therefore, the study by He et al. may be interesting to a wider, not only local audience.

However, the study by He et al. does not fulfill all of the requirements for a publication in a peer-reviewed scientific journal in its present form. I suggest that this study should be reconsidered after major revision.

General concept comments:

This study reports analysis of empirical data on post-fire vegetation recovery from subtropical forests in southwest China, presented in a well-structured way: Introduction, Methods, Results, Discussion, Conclusions. Since it is clearly a case study (1 fire, 2 vegetation surveys: 51 days and 171 days after fire), I would suggest a substantial title modification (e.g., “short-term understory revegetation”?) or adding a subtitle to the main title.

As the main strength of this study I see its novelty, as it presents new empirical data for the region.

Still, the paper by He et al. must be substantially improved. Generally, the English should be corrected, with many parts of the text rewritten or reworded. Numerous general statements should be specified (see ‘Specific comments’). Furthermore, I have encountered several issues in each of the manuscript sections which need improvement, presented below.

Introduction:

- language correction needed, some sentences (or parts of sentences) are impossible to understand (e.g., Line 43–45), please, see also ‘Specific comments’;

- quite many (in my opinion – too many) general statements, more specific explanation needed in several places (e.g., Line 29);

- if this study should provide support for ecological restoration in burned areas, more of that aspect should be presented in the ‘Introduction’.

Methods:

- source/-s of information for description of the study area needed (reference/-s);

- the description of fire severity assessment and the analysis of this variable must be improved: what do you mean by “blacking rate of trees” (Line 112)?; how this was evaluated/quantified?; where is the description of the analysis of the effect of fire severity on vegetation recovery/succession (the results presented in Fig. 3)?; there are several measures of fire severity (stem scorch, crown scorch, basal area, litter consumption depth, ash colour, etc.) (e.g., Turner et al. 1999; Úbeda et al. 2009; Diffendorfer et al. 2012), why you did not apply them? (for further reading see also: Agee 1993; Pyne et al. 1996; Scott et al. 2014)

Results:

- description: check carefully where the reference to a given figure/table should be placed (always at the end of the respective text);

- figures & tables: improve them, i.e., the description/title, description of axes, explanation of symbols, etc., so they are self-explanatory – they are not in the present form.

Discussion & Conclusions

- text must be improved: many general statements, language: often impossible to understand, unclear/unspecific passages, typos;

- reference usage: while discussing vegetation development after fires, at least three times (e.g., Line 397–399, 410–412, 416–417) Authors refer to studies which were actually not the studies on post-fire vegetation ecology/succession (they were not conducted in burned areas) [41, 43, 44]

Specific comments:

Line 1–2: Quite general title for a case study. I would suggest either a rephrasing or adding a more specific subtitle (see ‘General concept comments’).

Line 12: Repetition: “important”.

Line13–15: Sentence structure – reword.

Line 14: “topographic factors” – which precisely? Specify.

Line 16–17: “71 species, 52 genera, and 20 families” – of what?

Line 17: “gained” – unclear, what is meant here, reword or specify. “recoveryafter” – space missing (a typo).

Line 18: “vegetation diversity restoration” – what is meant here?, reword. Furthermore, I would suggest avoiding the term “restoration” and using “vegetation recovery” or “regeneration” instead, consequently throughout the manuscript. The term “restoration” is often used while referring to “ecosystem restoration” and not the process of natural succession. “The Margalef” (a typo)

Line 19: “sensitive” – to what? what is meant here?

Line 23–24: “Thereby providing…” – reword this sentence, combine with the previous one?

Line 28: “biome” – forests are biome? I suggest exchanging the word “biome” to “ecosystems”.

Line 28–31: quite general statements, specify, please. For such general statements: maybe a reference of a broader character or a couple of references should be used?

Line 33: “recycling” – what do you mean? Exchange to “cycling”.

Line 36–37: “duration after a fire” – duration of what?

Line 43–45: Rephrase this sentence. What do you mean by “When artificially intervening with different degree of burn areas”? “expected goals” – of what?

Line 47: Reference [11] is not a study of post-fire vegetation succession.

Line 50: “Slope”: remove capital letter (a typo).

Line 62–63: Rephrase this sentence.

Line 64: “restoration” – please, see my comment to Line 18.

Line 64–65: What do you mean by “large regions” and “small regions”? – unclear, specify.

Line 66: “The study of topographic factors on natural revegetation”: something missing, or? “the influence of topographic factors…”?

Line 67: “frequently uses a qualitative analysis” – please, provide reference for this statement.

Line 69: “or by different manners” – what do you mean?, specify.

Line 71: “Quadrat surveys were utilized to collect related data” – unprecise, specify. What are “quadrat surveys” (a reference?), “related data”?

Line 75: “understory vegetation” – maybe more specific, “vegetation recovery”? What about the effect of fire severity?

Line 85: “dimensions” – exchange to “factors”.

Line 87: “well-beings” – add a reference here, for the whole sentence (Line 85–87). “the other fire-prone areas” – which ones?

Line 87–88: “quite different” – how specifically?

Line 81–89: Add reference/-s to information about the study area

Line 89: “fire area is 200 hm²” – exchange to “was 200 km²”. “Debris flow caused by heavy rain after fire.” – I have to admit, I cannot understand this sentence, please, rephrase.

Line 89–92: Rephrase this sentence.

Line 90: “arbors” – ??? Do you mean “trees”?

Line 94–95: A general, unclear statement. Specify, rephrase.

Line 97: Exchange to “Vegetation inventory”.

Line 100: “among different burn intensities” – how this was evaluated? Please, decide to which fire regime characteristics you refer (fire intensity, fire severity, burn severity, etc.) (Agee 1993; Pyne et al. 1996; Keeley et al. 2009; Scott et al. 2014) and use this term consequently throughout the manuscript.

Line 102–106: Describe your vegetation inventory plots in a clearer way. When the name “shrub quadrats” appears for the first time (Line 102–103), the reader may be confused what is meant.

Line 104: “different degree of fire” – what do you mean? how this was classified?

Line 108: “the” – exchange to “each”.

Line 110–122: This should come before the information on methods of vegetation inventory, i.e., this section should appear before the section 2.2.

Line 110: Remove “disturbance”.

Line 111: “severity of forest fire disturbance” – exchange to “fire severity”.

Line 112: “blacking rate of trees” – what do you mean? how was it evaluated?

Line 113: “the branches and leaves” – only living branches and leaves, I guess? – please, specify.

Line 124–147: Is it possible to add reference/-s for the importance value and biodiversity indices? Some readers may wonder, where do those formulas come from.

Line 168: “with elevation, slope…” – why not with fire severity? Fire severity is also one of the key environmental factors affecting vegetation succession in burned areas. Correct “propertiesfor” (a typo).

Line 168–170: Rephrase, especially the part “natural restoration of vegetation diversity”.

Line 180: “elevation, slope, …” – and where is the effect of fire severity?

Line 201–202: Rephrase.

Line 202–203: Remove the sentence: “The importance values dominant species were shown in Figure 2.”.

Line 212: Add “(Figure 2)” after “herb species”.

Line 221: Add “(Figure 2)” after “species”.

Line 223–230: How this was tested?

Line 224: “fire” – “fire severity”, I guess?

Line 230: Add “(Figure 3)” at the end of this paragraph.

Line 232: Remove “of the” and “(Figure 3)”. Move “(Figure 3)” to the end of the text that refers to the results presented by Fig. 3 (Line 238?).

Line 233: “the other two burnings” – reword, be specific, please, see my comment to Line 100.

Line 242–243: “were burned at a low level” – Exchange to “were burned with low severity”.

Line 250: “margalef” – a capital letter needed (a typo).

Line 254: Remove “disturbance”.

Line 258: Remove the whole sentence in this line. Add “(Figure 4a)” at the end of this paragraph (Line 267).

Line 268–269: Remove the whole sentence, starting in Line 268. Add “(Figure 4b)” at the end of this paragraph (Line 277).

Line 280: “was significantly improved” – unclear, in relation to what? I would suggest avoiding the usage of the term “improve” since it requires further explanation.

Line 285: “Correlations” – exchange to “Correlation”.

Line 287: “wasnegatively” – space missing (a typo).

Line 289: “with strong tolerance” – to what?

Line 295–297: Please, verify the placement of “(Figure 5)”.

Line 336–358: Please, verify the placement of “(Figure 7)”.

Line 360: I would suggest a more specific title for this section.

Line 363–363: Rephrase.

Line 367: “is” – exchange to “was”.

Line 368: “strong tolerant” – to what?

Line 371–373: A verb is missing? – Rephrase.

Line 373–374: A reference for this statement?

Line 374: “complicated” – what do you mean?

Line 377: “hid” – exchange to “did” (a typo).

Line 384: “on vegetation restoration” – exchange to “short-term vegetation recovery”.

Line 387: More references?

Line 389: “showed” – exchange to “shown”.

Line 391: “the soil water” – did you mean “the ground water level”?

Line 392: “wind stronger” – exchange to “stronger wind” or “stronger winds”.

Line 394: “high tolerance” – to what?

Line 397–398: “After fire, understory…” – rephrase this sentence. Provide a reference for this statement. If also here the reference [41] should be used, like in the following sentence, then the usage here would be incorrect since the study [41] is not describing fire effects.

Line 399: Reference [41] is not a post-fire study.

Line 402–405: A reference for this statement?

Line 409: Rephrase.

Line 410–412: Reference [43] is not a post-fire study.

Line 416417: “improved” – in relation to what? Rephrase. Reference [44] is not a post-fire study.

Line 418: “positive vegetation succession” – what is it?

Line 422–423: “The restoration of shrubs may be particularly important” – why? Explain.

Line 429–446: Those are not really conclusions but a summary of the results. Rewrite.

Line 458–460: Rephrase. The reason for no availability is not given.

Line 571–572: Figure 1 – a broader geographical context would be nice – add a map of China? Asia?

Line 573–578: Figure 2 – what do the colors refer to? What do they mean? Explain, why some sections are green, yellow, orange, etc.

Line 580–582: Figure 3 – Explain how “different lowercase letters indicate significant difference”? What does “a”, “b”, “c”, “ab”, and “bc” mean?

Line 585: Rephrase the caption of Figure 4.

Line 587–579: Figure 5 – Add “biodiversity” to the title of the x axis?

Line 595–596: Figure 7 – Rephrase the figure’s caption. Explain the meaning of numbers.

Supplementary Material:

Table S1: What do you mean by “Spices”?

References:

Agee, J.K. 1993. Fire ecology of Pacific Northwest forests. Island Press, Washington, D.C.

Diffendorfer, J., Fleming, G.M., Tremor, S., Spencer, W. & Beyers, J.L. 2012. The role of fire severity, distance from fire perimeter and vegetation on post-fire recovery of small-mammal communities in chaparral. International Journal of Wildland Fire 21: 436–448.

Keeley, J.E. 2009. Fire intensity, fire severity and burn severity: a brief review and suggested usage. International Journal of Wildland Fire 18: 116–126.

Pyne, S.J., Andrews, P.L. & Laven, R.D. 1996. Introduction to wildland fire. 2nd. edition. John Wiley & Sons, New York.

Scott, A.C., Bowman, D.M.J.S., Bond, W.J., Pyne, S.J. & Alexander, M.E. 2014. Fire on Earth: an introduction. John Wiley & Sons, Ltd, Chichester.

Turner, M.G., Romme, W.H. & Gardner, R.H. 1999. Prefire heterogeneity, fire severity, and early postfire plant reestablishment in subalpine forests of Yellowstone National Park, Wyoming. International Journal of Wildland Fire 9: 21–36.

Úbeda, X. & Outeiro, L.R. 2009. Physical and chemical effects of fire on soil. In:  Fire effects on soils and restoration strategies, pp. 121–148. CRC Press.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report

The article investigates the influence of topographic factors on natural understory revegetation in burned areas. It is an interesting approach to an up-to-date theme in the light of the worldwide recent mega-fires disasters.

In the abstract as some more numerical results from the current analysis. It would be useful for the reader to have a clear view of the article by reading the abstract.

In the introduction, the wildfire problem and the cascading effects must be highlighted in a wider context.

In highly fire-prone ecosystems, loss of biodiversity, ecosystem function or services after wildfire events occurring with unnaturally high frequency, the magnitude of extent or intensity can result in land degradation or even complete transformation of the ecosystem. In the aftermath of wildfire accelerated erosion (Stefanidis et al. 2022) and flash flood phenomena occur (Wilder et al. 2021).  

Stefanidis, S., Alexandridis, V., Spalevic, V., & Mincato, R. L. (2022). Wildfire Effects on Soil Erosion Dynamics: The Case of 2021 Megafires in Greece. Agriculture & Forestry, 68(2), 49-63.

Wilder, B. A., Lancaster, J. T., Cafferata, P. H., Coe, D. B., Swanson, B. J., Lindsay, D. N., ... & Kinoshita, A. M. (2021). An analytical solution for rapidly predicting post‐fire peak streamflow for small watersheds in southern California. Hydrological Processes, 35(1), e13976.

Moreover, the footprint of wildfire on ecosystem services has raised the concern of the scientific community during the last decades. Therefore, numerous studies explore the advantages of geospatial technology to assess their effects (Stefanidis et al., 2022; Silvestro et al., 2021).

Stefanidis, S., Alexandridis, V., & Mallinis, G. (2022). A cloud-based mapping approach for assessing spatiotemporal changes in erosion dynamics due to biotic and abiotic disturbances in a Mediterranean peri-urban forest. CATENA, 218, 106564.

Silvestro, R., Saulino, L., Cavallo, C., Allevato, E., Pindozzi, S., Cervelli, E., ... & Saracino, A. (2021). The Footprint of Wildfires on Mediterranean Forest Ecosystem Services in Vesuvius National Park. Fire, 4(4), 95.

A location map of the study area is missing in the text.

Add some targets for future research that are linked with the current analysis.

The references style is not in line with the journal specifications. Please check and revise according to the instructions for the authors (https://0-www-mdpi-com.brum.beds.ac.uk/journal/fire/instructions).

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 3 Report

I found it very difficult to properly assess this manuscript because of major problems with english language expression. I think there are some very worthwhile results here but I cannot fairly assess the manuscript in its current form. I suggest that someone be asked to work with you on the english language expression and then you should submit the article as an original submission.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Round 2

Reviewer 2 Report

The article greatly improved compared with the previous version and now can be accepted for publication

Reviewer 3 Report

  This is a much improved manuscript. I think there are a few minor issues with english language presentation, but other than that it is ready for publication.