Differentiating Fire Regimes and Their Biophysical Drivers in Central Portugal

Round 1

Reviewer 1 Report

The article meets all the conditions to be published in the present version.

Author Response

We thank the reviewer for the attentive analysis of the manuscript.

Reviewer 2 Report

Well written article.  Methods are clear and appropriate.  Logic and conclusions are sound.  I recommend minor edits--mostly to correct English grammar.  I have indicated what corrections should be made where I could.  There are a few places in which I could not understand what was being said, so I couldn't fix the problem.  In those areas I would suggest explaining what you're trying to say to a native English speaker and asking them how to fix it.  Recommend publication after minor edits.  

Comments for author File: Comments.pdf

Author Response

We thank the reviewer for the attentive analysis of the manuscript and the many constructive suggestions.

In all cases not referenced here, the suggestion was followed, with the resulting change highlighted in grey in the revised manuscript. In cases when the comment is in the form of a question, an explanation is provided below. Excerpts which the reviewer considered of difficult interpretation were re-written to clarify their meaning.

Line 120: What do you mean by "burn extensively?"  Do you just mean "burn by wildfire over time?"  "Extensively" is a values word like "badly" or "greatly".

R:  By "burn extensively" we mean “burn across a relatively large area”. This use of the term is necessarily relative, as it is expressed using a scale variable. Therefore, a larger value of CPAB means that a larger area was affected by wildfires during the study period, i.e. the parish was more extensively burned.

Line 135: I don't understand the last part of this sentence about CPAB

R: The GCI quantifies the temporal concentration of burned area but disregards the extensiveness of this area. CPAB, contrarily, was employed to measure the tendency of parishes to suffer large burned areas over time. In this sense, both indicators are complementary. The phrase in question was changed to make this clearer to the reader (lines 142-144).

Line 567: What do you mean by "relevant damage?"

By "relevant damage?" we meant greater damage to persons and valuable assets and infrastructure, as opposed to damage to less valuable shrubland or forest areas. We used “relevant” in monetary terms. This term has now been removed from the phrase, and the reference to people and infrastructure has been made explicit (lines 582-584).

Reviewer 3 Report

This is an interesting paper that attempts to characterise fire regimes across 972 civil parishes in central Portugal (each 2-373 ha) and assess the importance of 12 “biophysical drivers” in shaping those regimes.  This is a valuable exercise, though I suspect there will be conflicting views about how well it has been done.  Nevertheless, I think it is worth publishing (with minor modifications) as part of a continuing conversation about how to tackle such questions.  The main need is to be more modest with the claims made for this paper.

I have a few specific comments that need to be addressed before publication:

Line 201, it is not true that “all” potential fire regime drivers are shown in Table 1 (or considered in this study).  Other potential drivers include vegetation structure and age; species composition (and varying flammability as a consequence); and management (including policies and programs for fuel reduction on private and public land).  Easily fixed by saying that the drivers considered in this paper are listed in Table 1, and admitting that many others could be influential.

Lines 275-277, “never burning” is a really important case, that deserves to be considered as a fifth fire regime.  Ideally the analysis should be redone with these 35 important parishes included (with zero values as appropriate): they will surely emerge as a fifth fire regime.  If it is impractical to redo the analysis, then these 35 parishes should be identified as a special case with a fifth fire regime.  Why did they escape fire?  That is a vitally important question.

Line 513, “inexistence of ignitions” is clumsy.  Perhaps change to “infrequency”.  Nowhere can expect never to have ignitions.

Line 575, there could be many other limitations (including a third one on wind that is actually mentioned here).  I recommend changing the sentence to “At least twothree main limitations/factors of uncertainty should be acknowledged in relation to this study.”

Line 616, I’d say 5 fire regimes not 4, the fifth being no burn recorded.

Lines 643-648 re policy & suppression strategy, this is a good point, not often raised in the literature.

References, I was surprised not to see more of the literature on fire regimes from elsewhere in southern Europe (especially Luis Brotons et al. in Spain) or other Mediterranean ecosystems such as Australia.  It would be good to see a more international selection of references.  Perhaps use the remarkable “fire current titles” database from USA, or refer to papers cited in Regos et al. (2015), J.Ornithology, DOI 10.1007/s10336-015-1174-9. 

Author Response

We thank the reviewer for the attentive analysis of the manuscript and the many constructive suggestions.

Changes to the text made in response to suggestions and comments by reviewer 3 are highlighted in green in the revised manuscript.

Line 201: it is not true that “all” potential fire regime drivers are shown in Table 1 (or considered in this study).  Other potential drivers include vegetation structure and age; species composition (and varying flammability as a consequence); and management (including policies and programs for fuel reduction on private and public land).  Easily fixed by saying that the drivers considered in this paper are listed in Table 1, and admitting that many others could be influential.

R: By “all potential fire regime drivers” we wished to mean “all the 12 drivers described in the text that precedes this sentence” (section 2.2.2.), i.e. the drivers used in this study. We understand that this reference to “all drivers” may deceive the reader and have changed the phrase to “A description of the 12 adopted potential fire regime drivers is shown in Table 1” (line 209). We do understand that many other drivers can influence fire regimes, as we have stated using several examples in section 4.4. (Limitations and Uncertainties).

 Lines 275-277: “never burning” is a really important case, that deserves to be considered as a fifth fire regime.  Ideally the analysis should be redone with these 35 important parishes included (with zero values as appropriate): they will surely emerge as a fifth fire regime.  If it is impractical to redo the analysis, then these 35 parishes should be identified as a special case with a fifth fire regime.  Why did they escape fire?  That is a vitally important question.

R: We thank the reviewer for raising this point. An analysis of these cases showed these parishes to comprise densely urbanized areas, with existing agricultural and forest patches showing a highly fragmented pattern. As the absence of burned areas during the 44-year study period shows that there are no conditions for wildfire occurrence in these parishes (either by lack of fuel or by lack of conditions for eventual ignitions to spread), we considered them to have no fire regime. We understand that this choice implied the assumption that some fire occurrence is a prerequisite for the existence of a fire regime, and that it could be argued that the absence of fire is, in itself, a fire regime. We have now included these considerations in lines 286-291.

 Line 513: “inexistence of ignitions” is clumsy.  Perhaps change to “infrequency”.  Nowhere can expect never to have ignitions.

R: We agree with the reviewer and have adopted the suggested term (line 529).

 Line 575: there could be many other limitations (including a third one on wind that is actually mentioned here).  I recommend changing the sentence to “At least three main limitations/factors of uncertainty should be acknowledged in relation to this study.”

R: We agree with the reviewer that many other limitations may exist. However, when we wrote that “two limitations/factors of uncertainty should be acknowledged” we meant two types of limitations, the first being the differences between the temporal scope of the used datasets, and the second the parameters employed to describe fire regimes and the biophysical drivers chosen. The issue of wind belongs to this second type, as it is a biophysical driver.

We have now made clear that we are referring to types of limitations, and that there may be others, by rephrasing the first sentence of the section as :“At least two types of limitations/factors of uncertainty should be acknowledged in relation to this study.” (line 592).

 Line 616: I’d say 5 fire regimes not 4, the fifth being no burn recorded.

R: We have considered the relation between the absence of burned area and the existence of fire regimes above (regarding the comment about lines 275-277).

 Lines 643-648: re policy & suppression strategy, this is a good point, not often raised in the literature.

R: We thank the reviewer for the compliment.

 References: I was surprised not to see more of the literature on fire regimes from elsewhere in southern Europe (especially Luis Brotons et al. in Spain) or other Mediterranean ecosystems such as Australia.  It would be good to see a more international selection of references.  Perhaps use the remarkable “fire current titles” database from USA, or refer to papers cited in Regos et al. (2015), J.Ornithology, DOI 10.1007/s10336-015-1174-9. 

R: In accordance with the reviewer’s suggestion, five references were added to the manuscript (highlighted in green in the reference list):

10. Brotons, N. Aquilué, M. de Cáceres, M. J. Fortin, and A. Fall, “How Fire History, Fire Suppression Practices and Climate Change Affect Wildfire Regimes in Mediterranean Landscapes,” PLoS One, vol. 8, no. 5, 2013, doi: 10.1371/journal.pone.0062392.
11. Díaz-Delgado, F. Lloret, and X. Pons, “Spatial patterns of fire occurrence in Catalonia, NE, Spain,” Landsc. Ecol., vol. 19, no. 7, pp. 731–745, 2004, doi: 10.1007/s10980-005-0183-1.
12. Piñol, K. Beven, and D. X. Viegas, “Modelling the effect of fire-exclusion and prescribed fire on wildfire size in Mediterranean ecosystems,” Ecol. Modell., vol. 183, no. 4, pp. 397–409, 2005, doi: 10.1016/j.ecolmodel.2004.09.001.
13. San-Miguel-Ayanz, J. M. Moreno, and A. Camia, “Analysis of large fires in European Mediterranean landscapes: Lessons learned and perspectives,” For. Ecol. Manage., vol. 294, pp. 11–22, 2013, doi: 10.1016/j.foreco.2012.10.050.
14. Moreira et al., “Wildfire management in Mediterranean-type regions: Paradigm change needed,” Environ. Res. Lett., vol. 15, no. 1, 2020, doi: 10.1088/1748-9326/ab541e.

 

Author Response File: Author Response.docx