Predicting Extreme-Precipitation Effects on the Geomorphology of Small Mountain Catchments: Towards an Improved Understanding of the Consequences for Freshwater Biodiversity and Ecosystems

Round 1

Reviewer 1 Report

Overall comments:

I think the title is not right. The paper deals not with the impact of extreme precipitation effects on biodiversity but with the impact of extreme precipitation effects on stream morphology and riparian vegetation. So I suggest to adapt the title accordingly.

In my opinion the paper is somewhat unbalanced. Its hinking on two lines of thought, it tries to relate the rainfall occurences to geomorphological effects and debris flows on the one hand and the relation with vegetation units on the other hand. The first line is received the most attention.

The study thus focuses on the hydrological effects of extreme preciitation efects on stream morphology and only at the end (chapter 5.3) the authors make a relation with Nature 2000 habitats and the riparian vegetation. The evidence is provided by 7 observations of habitat changes after the heavy precipitation events, which is rather indirectly. It is certainly not surprising that these events will change the habitats and the vegetation. This may however be a good starting point for further ecological monitoring and analysis of the recovering potential of such habitats, which is also suggested by the authors.

The paper shows effects by a number of photographs mostly taken after the rainfall occurences, it would be more interesting to show pictures of the same spots taken before and after the events for sound comparison. The satellite images only provide this evidence.

I suggest to shorten the paper drastically, mainly by reducing the number of figures (skip fig. 1 or combine with fig. 2, skip fig.3, choose between figs. 4, 5 and 8, choose between figs. 6 and 7, skip figs. , 10 and 12).

The  remaining figures should be improved in the sense that they should be self-explaining.

Detailed comments:

avoid the terms biodiversity and ecosystems in the abstract, key words and introduction. r. 108, r. 163, r.170 avoid these long references on websites in the text, provide a number and put these in the reference list. skip  r.172 to r. 180. fig. 6 I think the c should be indicated the paragraph above and should be changed into d. r.308 change the title of this paragraph: extreme precipitation effects on stream morphology and riparian vegetation in Nature 2000 habitats. chapter 5.3. Latin names should be cursive. 5. results and discussion. This is merely results, only at the end there are references about the occurrence of Niphargus species. 6. conclusion. Change this section into discussion and conclusions. Here I miss a discussion about the possible ecological impact of such extreme precipitation events, The authors should work further on this in more detail. For example, such events might not necessary be negative, since they can bring rejuvenation in the ecosystems, setting back the succession to earlier development stages.

 

 

 

Author Response

Response to Reviewer 1 Comments

 

Overall comments:

Point 1: I think the title is not right. The paper deals not with the impact of extreme precipitation effects on biodiversity but with the impact of extreme precipitation effects on stream morphology and riparian vegetation. So I suggest to adapt the title accordingly.

Response: the title has been modified according the Reviewer’s suggestions.

New title proposed: Predicting extreme-precipitation effects on the geomorphology of small mountain catchments: Towards an improved understanding of the consequences for freshwater biodiversity and ecosystems

However, we respectfully observe that the observations in our paper are not at all limited to riparian vegetation, including also, for instance, small mountain lakes and stygobiontic niphargids (amphipods, crustaceans) of Apennine aquifers.

Point 2: In my opinion the paper is somewhat unbalanced. Its hinking on two lines of thought, it tries to relate the rainfall occurrences to geomorphological effects and debris flows on the one hand and the relation with vegetation units on the other hand. The first line is received the most attention.

Response: Thank for this useful, and indeed correct, observations. We did our best to modify the article according the Reviewer’s suggestions, expanding and making more detailed the description and discussion of the ecological effects.

Point 3: The study thus focuses on the hydrological effects of extreme precipitation effects on stream morphology and only at the end (chapter 5.3) the authors make a relation with Nature 2000 habitats and the riparian vegetation. The evidence is provided by 7 observations of habitat changes after the heavy precipitation events, which is rather indirectly. It is certainly not surprising that these events will change the habitats and the vegetation. This may however be a good starting point for further ecological monitoring and analysis of the recovering potential of such habitats, which is also suggested by the authors.

Response: This part has been expanded (see response above), and we now particularly stress that we want to point to an understudied research direction (ecological effects of extreme precipitation events) that will become increasingly timely and important in the face of worsening climate change.

Point 4: The paper shows effects by a number of photographs mostly taken after the rainfall occurrences, it would be more interesting to show pictures of the same spots taken before and after the events for sound comparison. The satellite images only provide this evidence.

Response: Unfortunately, pre-event photographic documentation is not available for figs 15, 16 and 17. In the past it was not possible to predict that these sites would have a high probability to be affected by the effects of extreme-precipitation events. However, we regularly visit these sites for working reaons, and we can therefore testify the pre-event situation with our observations.  We inserted a paragraph explaining this in the paper. Moreover, as these sites are not included in the Natura 2000 network, a thematic habitat cartography is not available. Finally, we indeed did try to compare satellite images of the sites pre- and post-event but the resolution (scale) that can be reached is not sufficient for an effective and useful comparison. The depositional and erosive forms described in figs 15 and 16 were photographed Friday September 18th 2015, four days after the extreme event during the work done to assess and document the damages on behalf of the Civil-Protection authority and of the Geological Survey of the Emilia-Romagna Region.

Point 5: I suggest to shorten the paper drastically, mainly by reducing the number of figures:

skip fig. 1 or combine with fig. 2;

Response: Figure 1 was deleted.

skip fig.3;

Response: Done.

choose between figs. 4, 5 and 8;

Response: Figure 4 moved to Supplementary material;  Figure 5 deleted.

choose between figs. 6 and 7;

Response: We decided to keep these two figures because they describe the most impressive landforms, both for their high number, destructive power, and because they also significantly affected freshwater environments heavily. Figure 6 was combined with figure 7.

skip figs., 10 and 12.

Response:  Figure 10 combined with figure 9; Figure 12 moved to Supplementary material.

The remaining figures should be improved in the sense that they should be self-explaining.

Response: Done.

Detailed comments:

Point 6: avoid the terms biodiversity and ecosystems in the abstract, key words and introduction.

Response: We reduced and rationalised the use of these terms in the text of the paper. However, they are still used since we think that one of the interesting points of our paper is that we point to a research direction that deserves to be strongly expanded.

Point 7: r. 108, r. 163, r. 170 avoid these long references on websites in the text, provide a number and put these in the reference list.

Response: Done.

Point 8: skip r. 172 to r. 180.

Response: Done.

Point 9: fig. 6 I think the c should be indicated the paragraph above and should be changed into d.

Response: Figure 6 has been modified according the Reviewer’s suggestions.

Point 10: r. 308 change the title of this paragraph: extreme precipitation effects on stream morphology and riparian vegetation in Nature 2000 habitats.

Response: The title could not be changed because:

the extreme precipitation event affected mainly geographic areas located outside the Natura 2000 network; we also report ecological effects on small lakes, mires, and aquifers (niphargids).

 

Point 11: chapter 5.3. Latin names should be cursive.

Response: Fixed.

Point 12: 5. results and discussion. This is merely results, only at the end there are references about the occurrence of  Niphargus species.

Response: This was changed accordingly.

Point 13: 6. conclusion. Change this section into discussion and conclusions. Here I miss a discussion about the possible ecological impact of such extreme precipitation events, The authors should work further on this in more detail. For example, such events might not necessary be negative, since they can bring rejuvenation in the ecosystems, setting back the succession to earlier development stages.

Response: We expanded the Discussion, and added a Conclusions section.

Please see the attachment for file with changes highlighted

Author Response File: Author Response.docx

Reviewer 2 Report

Did you check the quality of meteorological data? Cite manuscripts about validation of meteorological data.

The research is very interesting and offers the opportunity for important future developments. 

 

Comments for author File: Comments.pdf

Author Response

Response to Reviewer 2 Comments

 

Point 1, r. 52: For scientific research, impersonal constructions are more suitable

Response: the text has been modified according the Reviewer’s suggestions.

 

Point 2, r.54: This must be paragraph 1.2 within the introduction

Response: done

 

Point 3, r.92: This must be paragraph 1.2 within the introduction

Response: done

 

Point 4, r.167: You must specify the projection of the coordinate system

Response:

Datum: WGS_1984

Projection system: Transverse Mercatore

Geographic Coordinate System: GCS_WGS_1984

 

Point 5, r.199:

Response: deleted “?”

 

Please see the attachment file with changes highlighted

 

 

Author Response File: Author Response.docx

Round 2

Reviewer 1 Report

General remarks:

You did a great job in improving the manuscript. The structure had been enormously improved and the present discussion section now provides a sound scientific argumentation. It now further deepens the relationship between the intensive hydro-morphologic effects and the various ecological environments with their characteristic vegetation types. this improves the importance of this paper to a great deal.

Detailed textual remarks: see in manuscript pdf

legends in figs 3, 4 and 5. rainfall classes 5-10, 10-25, etc. so avoid the decimals

r.222- 232 delete the red text

r.280 Arda must be Aveto

 

Author Response

Response to Reviewer 1 Comments

 

General remarks:

You did a great job in improving the manuscript. The structure had been enormously improved and the present discussion section now provides a sound scientific argumentation. It now further deepens the relationship between the intensive hydro-morphologic effects and the various ecological environments with their characteristic vegetation types. this improves the importance of this paper to a great deal.

Point 1: Detailed textual remarks: see in manuscript pdf

Response: Done

 

Point 2: legends in figs 3, 4 and 5. rainfall classes 5-10, 10-25, etc. so avoid the decimals

Response: Done

 

Point 3: r.222- 232 delete the red text

Response: Done

 

Point 4: r.280 Arda must be Aveto

Response: Done