Evaluation of the Restoration Effects of Rooftop Greening Areas Created by Applying an Ecological Restoration Method

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

 

The authors ask an interesting question that is not often directly addressed: how does a green roof created using techniques of ecological restoration compare with green roofs established using standard landscape architecture techniques?

 

The study compares three green roofs on the same university campus, one was planted with native species to imitate a specific native forest ecosystem (Korean red pine forest), a second had grassland and shrubland, the third just grassland. The native green roof was planted with pines and soil collected from a natural area was added to introduce other plant species that would occur at the natural site. Tree growth was measured as were several ecophysiological variables (photosynthetic and transpiration rates). Other variables, including air temperature and soil respiration were compared among sites. Species composition, herb layer productivity, and aboveground carbon stock (trees) was measured on each roof as well. Finally, they conducted an insect survey. The restoration roof appears to outperform the other green roof types for reducing air temperature and carbon sequestration, and has similarities in community structure and some functions to the reference site. This study has potential and could be of great interest to the green roof research community. However, there are major issues with the presentation and explanation of the methods, as well as some issues with framing the native forest roof as 'ecological restoration'. I think the paper has potential and should be reconsidered after major revisions.

 

I think the authors need to be more careful with the language related to "ecological restoration"; e.g. it's not ecological restoration that they are doing on a green roof, it is a habitat replication or creation; that said, I do agree that the reference system comparison approach is interesting and valid, but not to the extent of claiming that the green roof is an ecological restoration. Therefore it does not make sense to call the green roof with native ecosystem the 'ecological restoration site'. Also, the authors make the case that using the habitat template method to choose plants for the green roof site is important. A strength of this paper is that the authors compare ecosystem functions between reference site and green roof, which is rarely done in the green roof field. However, it seems to me that setting up a green roof with any tree species, provided they can grow successfully will lead to a green roof with high levels of ecosystem service provisioning (e.g. carbon sequestration and air temperature reductions). The fact that there is a similar community assembly to the reference site happening on the 'restoration' roof is not necessarily the reason that it performs ecological functions well. I think this needs to be spelled out in the paper. I appreciate that the structural comparisons (e.g. NMDS graphs) show that the restoration roof is similar to the reference site but why does this matter in an urban context in an artificial environment? The value of having native plants from a mountain ecosystem in a city is not made clear by the authors.

 

The timeframe for the study is unclear: when were the roofs constructed? How many years of data were collected? This needs to be clearly spelled out in the methods. If this is true, this is a very long green roof study and should be mentioned in the abstract and introduction as this is a strong feature of the study (there are very few long term green roof studies!).

 

More information about the reference site also needs to be included. Since the authors are comparing NPP between reference sites and geen roofs, the age of the forest at the reference site is important in interpreting the comparison. More information about the green roofs should also be included in the methods. Was maintenance (e.g. weeding) carried out on the roofs? Also, with such a long term experiment, are there other studies that have been published from this system? These should be cited if they exist.

 

Details

-lns 101-102: wording is confusing here; are the authors saying that the landscaped green roofs are being used as reference sites?

 

-lns 113-114: please confirm: were trees present on the landscaped roofs or just the 'ecological restoration' roof?

 

-ln 129: where were the sensors installed? On the roofs and at the natural forest site? What is meant by "each distance"?

 

-ln166: please confirm: are these equations including belowground and aboveground biomass? Usually these are just aboveground biomass but the authors use 'total' biomass in the table caption.

 

Figure 2 and 3 can be combined into a single figure with two panels. I'm not sure about the purpose of figures 2,3,4,5 without comparison to natural growth conditions (reference site?). To me it shows that there is a forest establishing on a green roof but it seems like a lot of effort without a quantitative comparison to anything else. For example, Figure 7 shows a clear comparison of air temperatures among the three roofs and reference site. (Figure 8 also has the comparison). Is it possible to have some kind of reference comparison with the Pinus densiflora data shown in Figures 2-5? Otherwise, I suggest it might be better to put Figures 2-5 in an appendix, not in the main paper. Having now read the discussion, I still think it makes sense to put these figures in an appendix and still refer to them in the results and discussion.

 

Table 6. It is not clear in the methods how belowground biomass was calculated.

 

lns 288-303: Were there no herbaceous species in the ecological restoration green roof? Since soil was added and no maintenance performed there should be something else growing up there or is it really just pine trees on that roof? (or was there maintenance performed? This should be clearly outlined in the methods). In the appendix, I see that there were herbaceous species on the restoration roof. I think this should be mentioned in the results.

 

lns 339-342 Given that the reference site is on a mountain, are there other forest types that occur closer to the city that would be more appropriate as a habitat template for green roofs?

 

ln 345: Again, I don't agree with using 'ecological restoration' to describe a green roof.

 

lns 381-388: More information and context about the importance of soil respiration rate should be included here. Is a higher rate 'better'? If so, why? What is the relationship between soil respiration and net carbon sequestration? (I think that more soil respiration means less carbon being stored in the soil, but this is not my expertise). There are few studies on green roofs that have reported soil respiration, so its importance should be clarified by the authors.

 

lns 408-417: The authors are using the term 'functional traits' incorrectly. I think changing to just 'function' makes sense here; they are comparing ecological functions, not functional traits per se.

 

lns 414-417: The link between community assembly and ecosystem functioning is not clear and certainly has not been established by the authors. As stated above, there is no evidence presented here that the key ecological functions shown by the restoration green roof exist because of the species and soil used. My guess is that any treed green roof would perform well for carbon sequestration and temperature reductions. This sentence also needs to be re-written as the part about the landscape architecture approach is confusing.

 

lns 437-439: The finding of specialist ants at the restoration roof and the reference site is interesting and does confirm that this approach is effective creating a similar habitat to a native habitat. However, the statement that the habitat function is better on the restoration roof compared to the landscape roofs needs to be backed up by more references or other information.

 

section 4.5 This reads like introduction material and does not discuss the results of the study. I think this section can be deleted.

 

Comments on the Quality of English Language

I did not have time for detailed copy editing but there are many places where stylistic issues arise in the writing. The whole thing should be gone over to check for appropriate style and minor grammar issues. There are a few places where the authors' meaning is unclear (details shown above).

Author Response

Response to reviewer’s comments

Dear Reviewer:

Thank you for reviewers’ valuable advice and comments. We answered faithfully to reviewers’ questions and revised our manuscript be reflecting reviewers’ valuable advice and comments.

Thank you again for reviewers’ kind advice and comments.

Sincerely Yours,

Chang Seok Lee

Reviewer #1

Comments and Suggestions for Authors

The authors ask an interesting question that is not often directly addressed: how does a green roof created using techniques of ecological restoration compare with green roofs established using standard landscape architecture techniques?

The study compares three green roofs on the same university campus, one was planted with native species to imitate a specific native forest ecosystem (Korean red pine forest), a second had grassland and shrubland, the third just grassland. The native green roof was planted with pines and soil collected from a natural area was added to introduce other plant species that would occur at the natural site. Tree growth was measured as were several ecophysiological variables (photosynthetic and transpiration rates). Other variables, including air temperature and soil respiration were compared among sites. Species composition, herb layer productivity, and aboveground carbon stock (trees) was measured on each roof as well. Finally, they conducted an insect survey. The restoration roof appears to outperform the other green roof types for reducing air temperature and carbon sequestration, and has similarities in community structure and some functions to the reference site. This study has potential and could be of great interest to the green roof research community. However, there are major issues with the presentation and explanation of the methods, as well as some issues with framing the native forest roof as 'ecological restoration'. I think the paper has potential and should be reconsidered after major revisions.

I think the authors need to be more careful with the language related to "ecological restoration"; e.g. it's not ecological restoration that they are doing on a green roof, it is a habitat replication or creation; that said, I do agree that the reference system comparison approach is interesting and valid, but not to the extent of claiming that the green roof is an ecological restoration. Therefore it does not make sense to call the green roof with native ecosystem the 'ecological restoration site'. Also, the authors make the case that using the habitat template method to choose plants for the green roof site is important. A strength of this paper is that the authors compare ecosystem functions between reference site and green roof, which is rarely done in the green roof field. However, it seems to me that setting up a green roof with any tree species, provided they can grow successfully will lead to a green roof with high levels of ecosystem service provisioning (e.g. carbon sequestration and air temperature reductions). The fact that there is a similar community assembly to the reference site happening on the 'restoration' roof is not necessarily the reason that it performs ecological functions well. I think this needs to be spelled out in the paper. I appreciate that the structural comparisons (e.g. NMDS graphs) show that the restoration roof is similar to the reference site but why does this matter in an urban context in an artificial environment? The value of having native plants from a mountain ecosystem in a city is not made clear by the authors.

☞ In order to reduce misunderstanding, we revised it to a site where the ecological restoration method is applied. However, it is difficult to agree with the view that it is okay to choose a plant that can grow well on the roof of any tree species. This is because even though carbon sequencing and air temperature reduction may be possible when such a plant is introduced, there may be a difference in promoting biodiversity by maintaining connectivity with the surrounding ecosystem. In fact, the place where the ecological restoration method was applied tended to be similar to the insect fauna of the reference site and have high species diversity, unlike the place where the existing landscape method was applied. We would like to use these results as the value of having native plants of mountainous ecosystems in the city.

The timeframe for the study is unclear: when were the roofs constructed? How many years of data were collected? This needs to be clearly spelled out in the methods. If this is true, this is a very long green roof study and should be mentioned in the abstract and introduction as this is a strong feature of the study (there are very few long term green roof studies!).

☞ We added the timeframe for the study. Lines 103 – 105.

More information about the reference site also needs to be included. Since the authors are comparing NPP between reference sites and geen roofs, the age of the forest at the reference site is important in interpreting the comparison. More information about the green roofs should also be included in the methods. Was maintenance (e.g. weeding) carried out on the roofs? Also, with such a long term experiment, are there other studies that have been published from this system? These should be cited if they exist.

☞ We added the ages of the individuals that make up the pine trees by reflecting the reviewer’s advice. Lines 100 – 101. Artificial management, such as weeding, was excluded from the experimental site.

 

Details

-lns 101-102: wording is confusing here; are the authors saying that the landscaped green roofs are being used as reference sites?

☞ Yes. We selected places to which landscaping methods were applied along with natural forests as reference sites in order to evaluate the restoration effect of places to which ecological restoration was applied.

-lns 113-114: please confirm: were trees present on the landscaped roofs or just the 'ecological restoration' roof?

☞ Trees were introduced only in the site where ecological restoration was applied.

-ln 129: where were the sensors installed? On the roofs and at the natural forest site? What is meant by "each distance"?

☞ We installed the sensors on all study sites including the site where the ecological restoration method was applied, landscape architecture 1 and 2, and natural forest selected as a reference site.

-ln166: please confirm: are these equations including belowground and aboveground biomass? Usually these are just aboveground biomass but the authors use 'total' biomass in the table caption.

☞ It includes the below ground biomass as was shown in those equations.

Figure 2 and 3 can be combined into a single figure with two panels. I'm not sure about the purpose of figures 2,3,4,5 without comparison to natural growth conditions (reference site?). To me it shows that there is a forest establishing on a green roof but it seems like a lot of effort without a quantitative comparison to anything else. For example, Figure 7 shows a clear comparison of air temperatures among the three roofs and reference site. (Figure 8 also has the comparison). Is it possible to have some kind of reference comparison with the Pinus densiflora data shown in Figures 2-5? Otherwise, I suggest it might be better to put Figures 2-5 in an appendix, not in the main paper. Having now read the discussion, I still think it makes sense to put these figures in an appendix and still refer to them in the results and discussion.

☞ We think that we need such data to show the settlement process of rooftop greening that we performed. The comparison was made in the discussion section. Lines 355 – 356.

Table 6. It is not clear in the methods how belowground biomass was calculated.

☞ They were obtained by substituting it for the allometric equations provided by the Korean government as was referred in Materials and Methods section. Lines 165 – 166.

lns 288-303: Were there no herbaceous species in the ecological restoration green roof? Since soil was added and no maintenance performed there should be something else growing up there or is it really just pine trees on that roof? (or was there maintenance performed? This should be clearly outlined in the methods). In the appendix, I see that there were herbaceous species on the restoration roof. I think this should be mentioned in the results.

☞ There are herbaceous plants. We mentioned that we sprayed topsoil collected from pine forests to introduce herbaceous plants in the Materials and Method section.

lns 339-342 Given that the reference site is on a mountain, are there other forest types that occur closer to the city that would be more appropriate as a habitat template for green roofs?

☞ As you know, the roof of the building is made of a material derived from limestone. Also, it exists in the same state as a rocky mountain where the parent rock is exposed. Therefore, we think that all vegetation established in limestone areas or outcrops is suitable as a habitat template for green roofs. And now, more and more researchers are trying to apply this method to create green roofs.

ln 345: Again, I don't agree with using 'ecological restoration' to describe a green roof.

☞ We revised it to a site where the ecological restoration method is applied to reduce misunderstanding.

lns 381-388: More information and context about the importance of soil respiration rate should be included here. Is a higher rate 'better'? If so, why? What is the relationship between soil respiration and net carbon sequestration? (I think that more soil respiration means less carbon being stored in the soil, but this is not my expertise). There are few studies on green roofs that have reported soil respiration, so its importance should be clarified by the authors.

☞ It is not to say that high soil respiration rates are good. However, it can be evaluated positively that seasonal changes in soil respiration rates are consistent with those measured in natural forests. On the other hand, the fact that seasonal changes in soil respiration rates are not clear in sites applying existing landscaping methods can be interpreted as indicating that such places are not playing a role in supporting biodiversity.

lns 408-417: The authors are using the term 'functional traits' incorrectly. I think changing to just 'function' makes sense here; they are comparing ecological functions, not functional traits per se.

☞ Functional traits are widely used as shown in the definition of "Functional tracks are morphological, biochemical, physiological, structural, phenological or behavioral characteristics of organisms that influence performance or fitness." The characteristics we used in this study were also used as the term "life history characteristics" in the past, but they are included in functional traits today.

lns 414-417: The link between community assembly and ecosystem functioning is not clear and certainly has not been established by the authors. As stated above, there is no evidence presented here that the key ecological functions shown by the restoration green roof exist because of the species and soil used. My guess is that any treed green roof would perform well for carbon sequestration and temperature reductions. This sentence also needs to be re-written as the part about the landscape architecture approach is confusing.

☞ This part was supplemented to help readers understand. Lines 446 – 453.

lns 437-439: The finding of specialist ants at the restoration roof and the reference site is interesting and does confirm that this approach is effective creating a similar habitat to a native habitat. However, the statement that the habitat function is better on the restoration roof compared to the landscape roofs needs to be backed up by more references or other information.

☞ One example is that the ecological restoration site has a higher species diversity of insects and its composition is more similar to that of the reference site compared to the site where the landscaping method was applied. In addition, the fact that the seasonal changes in soil respiration are clear and the seasonal changes similar to those of natural forests can also be interpreted as meaning that the soil has been stabilized and the biodiversity-supporting function has been improved. These results can be used as evidence that rooftop greening applying the ecological restoration method has better habitat functions than places applying the existing landscape method.

Reflecting these results, the method of rooftop greening has been transformed beyond the subjective landscaping method to an ecological restoration method that benchmarks actual nature. We addressed such a process of change in the next section.

section 4.5 This reads like introduction material and does not discuss the results of the study. I think this section can be deleted.

☞ This part contains important content that shows the transition process of the rooftop greening methods. Therefore, I'd like to keep the content.

Comments on the Quality of English Language

I did not have time for detailed copy editing but there are many places where stylistic issues arise in the writing. The whole thing should be gone over to check for appropriate style and minor grammar issues. There are a few places where the authors' meaning is unclear (details shown above).

☞ In order to solve this problem, we went through an English review process through a native speaker.

Author Response File: Author Response.docx

Reviewer 2 Report

Comments and Suggestions for Authors

Detailed commnets:

1) The lack of illustrations - any images, photos from the green roofs and reference site. The photographs for every site should be added.

2) Figure 4,5 - equation should be described correctly (not y and x, but year and crg)

3) Table 2 - equtions need sources (here also, only in the text is not sufficient)

4) 2.6.1 - why different sizes on different sites - it need explanation

5) 2.1. - description of sites requires adding the types of green roofs (intensive, extensive) which is used in the text later;

6) figure 6 - axis should be descibed correctly (not only units fo OY), what is PPFD?

7) lines 219 - 224 - should be corrected - not understable, errors?

8) line 233; 0,4 Celsius degree is significance, what with the daytime? the differences are not significance? why there is no information in the text about it?

8) in conclusion there is no information about sites landscaper architecture 1 and 2

9) NPP - and other shrot names should be explained (for insance line 275)

10) lines 264 - 268 - should be double checke adn corected - there are not consistent.....

11) 4.4 - too long, it is rather introduction, not discussion, should be reorganized

12) in 4.4. should be listed withe name of species examples of plants...

13) figure 10 - description is not accurate -AXIS I os for x=0, but is not visible at he graph, so used it as a reference (at right side of AXIS I) is not good idea...

 

 

 

Comments on the Quality of English Language

no comments

Author Response

Response to reviewer’s comments

Dear Reviewer:

Thank you for reviewers’ valuable advice and comments. We answered faithfully to reviewers’ questions and revised our manuscript be reflecting reviewers’ valuable advice and comments.

Thank you again for reviewers’ kind advice and comments.

Sincerely Yours,

Chang Seok Lee

Reviewer #2

Comments and Suggestions for Authors

Detailed commnets:

1) The lack of illustrations - any images, photos from the green roofs and reference site. The photographs for every site should be added.

☞ We added photos of the study sites.

2) Figure 4,5 - equation should be described correctly (not y and x, but year and crg)

☞ We revised the Figures by accepting reviewer’s comment.

3) Table 2 - equtions need sources (here also, only in the text is not sufficient)

☞ We added it by accepting reviewer’s comment.

4) 2.6.1 - why different sizes on different sites - it need explanation

☞ In a vegetation survey, the plot size is determined by the height of the vegetation. In this study, the plot size was determined according to the rule.

5) 2.1. - description of sites requires adding the types of green roofs (intensive, extensive) which is used in the text later;

☞ We added them in site description by accepting reviewer’s comment.

6) figure 6 - axis should be descibed correctly (not only units fo OY), what is PPFD?

☞ We added them in caption of Figure 6.

7) lines 219 - 224 - should be corrected - not understable, errors?

☞ We measured the Water Use Efficiency by applying the appropriate method and compared the values with other plants in the genus Pinus. Furthermore, from such results, it could be judged that pine trees are suitable for introduction into dry and poor environments such as the roof of a building.

8) line 233; 0,4 Celsius degree is significance, what with the daytime? the differences are not significance? why there is no information in the text about it?

8) in conclusion there is no information about sites landscaper architecture 1 and 2

☞ We revised “Conclusion” section by reflecting reviewer’s comment.

9) NPP - and other shrot names should be explained (for insance line 275)

☞ We added explanation for short names.

10) lines 264 - 268 - should be double checke adn corected - there are not consistent.....

☞ We revised the part.

11) 4.4 - too long, it is rather introduction, not discussion, should be reorganized

☞ This part explains the transition process of the rooftop greening methods to explain the background that this study is different from the existing landscaping method. Therefore, it is judged to be a suitable part for discussion rather than an introduction, and I'd like to keep the current state.

12) in 4.4. should be listed withe name of species examples of plants...

☞ We added examples of plants.

13) figure 10 - description is not accurate -AXIS I os for x=0, but is not visible at he graph, so used it as a reference (at right side of AXIS I) is not good idea...

☞ We revised Figure 10 by increasing the resolution.

Author Response File: Author Response.docx

Reviewer 3 Report

Comments and Suggestions for Authors

Comments and Suggestions for Authors

The manuscript entitled: “Evaluation of the restoration effect of rooftop greening area created by applying ecological restoration method” is very interesting. The topic is important due to the need of the climate change mitigation and adaptation. The aim of the study was to evaluate the restoration effects on the green roof treated by applying ecological restoration method to reinforce habitat function. As the reference ecosystem for ecological restoration Authors have selected the Korean red pine stand established on Mt. Bulam. The obtained results of the investigation show that the high growth rate and the water-use efficiency of the planted Korean red pines have stabilized the settlement on the rooftop. The results of the study have confirmed that rooftop greening applying the ecological restoration method has a better biological habitat function than green roofs applying existing landscape architecture methods. Authors have emphasized that the ecological restoration method could guarantee the growth of planted species and meet the habitat function.

Below are presented specific comments to the Manuscript: forests-3042560.

1. In the section “Materials and Methods” Authors could more detailed explain when were conducted the investigations.

 

2. The authors should determine the directions of further research in this field that are planned in the future.

 

3. The numbering of equations can be improved. Equation number (1) is used correctly, but expressions marked as (2), (3), and (4) are not equations but the explanations.

Below are given additional indications concerning the text.

·         Authors could explain whether “D” in the table 2 is the diameter. The information about the units of D can be also provided.

·         In the Line containing equation (4)  – The expression should be probably: mmol H₂O m^-2 s^-1.

·         Line 217 – Authors could explain the abbreviation PPFD in the X-axis.

·         Line 319  - Please, replace the expression “Zoysia jaonica” with an expression: “Zoysia japonica “.

Comments for author File: Comments.pdf

Author Response

Response to reviewer’s comments

Dear Reviewer:

Thank you for reviewers’ valuable advice and comments. We answered faithfully to reviewers’ questions and revised our manuscript be reflecting reviewers’ valuable advice and comments.

Thank you again for reviewers’ kind advice and comments.

Sincerely Yours,

Chang Seok Lee

Reviewer #3

Comments and Suggestions for Authors

The manuscript entitled: “Evaluation of the restoration effect of rooftop greening area created by applying ecological restoration method” is very interesting. The topic is important due to the need of the climate change mitigation and adaptation. The aim of the study was to evaluate the restoration effects on the green roof treated by applying ecological restoration method to reinforce habitat function. As the reference ecosystem for ecological restoration Authors have selected the Korean red pine stand established on Mt. Bulam. The obtained results of the investigation show that the high growth rate and the water-use efficiency of the planted Korean red pines have stabilized the settlement on the rooftop. The results of the study have confirmed that rooftop greening applying the ecological restoration method has a better biological habitat function than green roofs applying existing landscape architecture methods. Authors have emphasized that the ecological restoration method could guarantee the growth of planted species and meet the habitat function.

Below are presented specific comments to the Manuscript: forests-3042560.

1. In the section “Materials and Methods” Authors could more detailed explain when were conducted the investigations.

☞ We revised “Materials and Methods” section by explaining in more detail.

2. The authors should determine the directions of further research in this field that are planned in the future.

☞ We added future plans.

3. The numbering of equations can be improved. Equation number (1) is used correctly, but expressions marked as (2), (3), and (4) are not equations but the explanations.

☞ We revised them.

 

Below are given additional indications concerning the text.

• Authors could explain whether “D” in the table 2 is the diameter. The information about the units of D can be also provided.

☞ We revised them.

• In the Line containing equation (4)  – The expression should be probably: mmol H₂O m^-2 s^-1.
• Line 217 – Authors could explain the abbreviation PPFD in the X-axis.

☞ We explained it.

• Line 319- Please, replace the expression “Zoysia jaonica” with an expression: “Zoysia japonica “.

☞ Thank you. We revised it.

Author Response File: Author Response.docx

Reviewer 4 Report

Comments and Suggestions for Authors

This is a nice paper which would be a valuable addition to the literature on green roofs.

The paper would benefit from being revised by a native English speaker, as this would make it more intelligible to an international audience. For example, the use of the definite article is often incorrect, which can be confusing.

My main criticism is that the references cited are all quite old, and do not reflect any of the recent research that has been carried out on applying ecological restoration methods to greening rooftop. A Google Scholar search will easily reveal these. The findings from this study need to be considered in the light of this recent research.

Comments on the Quality of English Language

The paper would benefit from being revised by a native English speaker.

Author Response

Response to reviewer’s comments

Dear Reviewer:

Thank you for reviewers’ valuable advice and comments. We answered faithfully to reviewers’ questions and revised our manuscript be reflecting reviewers’ valuable advice and comments.

Thank you again for reviewers’ kind advice and comments.

Sincerely Yours,

Chang Seok Lee

Reviewer #4

Comments and Suggestions for Authors

This is a nice paper which would be a valuable addition to the literature on green roofs.

The paper would benefit from being revised by a native English speaker, as this would make it more intelligible to an international audience. For example, the use of the definite article is often incorrect, which can be confusing.

My main criticism is that the references cited are all quite old, and do not reflect any of the recent research that has been carried out on applying ecological restoration methods to greening rooftop. A Google Scholar search will easily reveal these. The findings from this study need to be considered in the light of this recent research.

☞ We went through English reviews by native speakers and reinforced recent research by accepting reviewer’s comment.

Comments on the Quality of English Language

The paper would benefit from being revised by a native English speaker.

☞ We went through English reviews by native speakers by accepting reviewer’s comment.

Author Response File: Author Response.docx

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

Thank you for your detailed response.

Comments on the Quality of English Language

Minor editing required. I hope that the journal will provide appropriate copy editing. One example: "this is intensive green roofs." should be "these are intensive green roofs" or "this is an intensive green roof". It is my opinion that the journal should fix these issues in the copy editing/proofs stage.

Reviewer 4 Report

Comments and Suggestions for Authors

The revised manuscript is now acceptable