The Role of Spontaneous Flora in the Mitigation of Particulate Matter from Traffic Roads in an Urbanised Area

Round 1

Reviewer 1 Report

 

The manuscript “The role of spontaneous flora in the protection of particulate matter air pollution from traffic roads in an urbanised area” presents an interesting new approach on the air pollution problem, considering spontaneous flora as possible contributor to reduce air pollution near roadways by accumulating PM on their leaves. I found the manuscript clear, pleasant to read, and relevant for the field of interest. The experimental design was appropriate to test the hypothesis, and the conclusions were consistent with the evidence and arguments presented. The cited references were relevant and overall recent publications (with 9 self-citations on pertinent topics).

 

Corrections:

Line 33:

PM varies in size, composition, and origin, consisting of more than 50 chemical components

I would be more general, it does not always consist of those components, I would add “could consist of..”

Line 66:

result of human activities such as the dropping of seeds or plant spores that germinate in urban conditions

This is unclear, please clarify.

Lines 81-82:

Moreover, to check 81 the effectiveness of the plants, the amount of PM in the air of different fractions was investigated.

This is not clear, please rephrase.

Lines 98-99:

The selected study area was located in the northeast part of Tarnów and were represented by green spaces along a paved road, bicycle path and unpaved road.

Check English

Lines 102-103:

The study areas included five green spaces, and four study plots were distinguished in each zone with the growing plant species recognised.

This is unclear, please clarify.

Lines 104-105:

Zones I, II, and III had only a herbaceous 104 layer, while zones IV and V had herbaceous shrubs and tree layers

Use the same numbering system throughout the text and in the figure.

Lines 128-129

at least five successive dry days were observed before collection

Improve the English of this sentence

Line 197

shrub species such as Salix sp., Sambucus nigra L

Improve the English of this sentence (add a verb)

Table 1: I don’t understand the %: for instance, in zone II plot 1 and in zone III plot 2 the % don’t add up to 100%. Correct the % or implement in the text because it is not clear.

Fig 3 legend:

The quantity of Total PM amassed on the leaves of plants

Accumulated?

Line 230

as demonstrated in Figure 3.

Shown?

Line 240

depicted in Figure 5C)

4C

Lines 260-261

while the concentration of PM2.5 exceeded the limit (25 μg/m3) in the further distance in Zones I and II.

Improve the English of this sentence

Line 358

Herbaceous species in this study has a high

have

Line 369

Moving

Mowing

Line 385

in the least effective zone III.

in the least effective zone (zone III).

Line 400

Also study conducted in Beijing found that different plant species had

Improve the English of this sentence.

Line 425

from the road, but for shrubs, there was a significant increase between Zone IV

Delete the underlined comma.

Line 451

to fully utilise the ability of plants to purify

Improve the English of this sentence.

Line 457

This requires

Are you referring to two sentences before? It’s not clear please improve it.

 

Author Response

Our responses are in italic, just below the reviewers’ comments while in the manuscript as tracked changes.

 

Reviewer 1

The manuscript “The role of spontaneous flora in the protection of particulate matter air pollution from traffic roads in an urbanized area” presents an interesting new approach on the air pollution problem, considering spontaneous flora as possible contributor to reduce air pollution near roadways by accumulating PM on their leaves. I found the manuscript clear, pleasant to read, and relevant for the field of interest. The experimental design was appropriate to test the hypothesis, and the conclusions were consistent with the evidence and arguments presented. The cited references were relevant and overall recent publications (with 9 self-citations on pertinent topics).

 We are grateful for the reviewer’s helpful and constructive comments. In our opinion the research project is innovative. We hope that in our research we managed to study and interpret the most important aspects of the phytoremediation function of roadside spontaneous flora.

 

Line 33: PM varies in size, composition, and origin, consisting of more than 50 chemical components I would be more general, it does not always consist of those components, I would add “could consist of.”

Thank you for suggestion. We corrected the as you suggested.

Line 66: result of human activities such as the dropping of seeds or plant spores that germinate in urban conditions. This is unclear, please clarify.

Thank you for your suggestion. We have corrected all sentence: Nevertheless, they can sometimes arise also due to human activities, such as the drop-ping of seeds or plant spores that germinate in the urban environment.

Lines 81-82: Moreover, to check 81 the effectiveness of the plants, the amount of PM in the air of different fractions was investigated. This is not clear, please rephrase.

The whole sentence was rephased: In order to assess the efficacy of plants in mitigating PM pollution, (3) the concentration of PM particles of three distinct size fractions in the air was measured.

Lines 98-99: The selected study area was located in the northeast part of Tarnow and were represented by green spaces along a paved road, bicycle path and unpaved road. Check English

Thank you for suggestion. Whole sentence was rewritten: The study site chosen for this research was situated in the north-eastern part of Tarnow and was comprised of green spaces running along a paved road, a bicycle path, and an unpaved road.

Lines 102-103: The study areas included five green spaces, and four study plots were distinguished in each zone with the growing plant species recognized. This is unclear, please clarify.

Thank you for this. We corrected the sentence to make it clearer: Five green spaces (zone I-V) were chosen as study areas, with each zone further submited into four distinct study plots based on the identified plant species.

Lines 104-105: Zones I, II, and III had only an herbaceous 104 layer, while zones IV and V had herbaceous shrubs and tree layers Use the same numbering system throughout the text and in the figure.

We have changed the Figure 1. Now the zones are the same as in the text.

Lines 128-129 at least five successive dry days were observed before collection. Improve the English of this sentence

Thank you for suggestion. The we improved English: To ensure deposition of PM on the plants, the collection was carried out only after a minimum of five consecutive dry days, as precipitation has the potential to wash away PM particles from the foliage.

Line 197 shrub species such as Salix sp., Sambucus nigra L. Improve the English of this sentence (add a verb)

Thank you, we corrected sentence adding verb.

Table 1: I don’t understand the %: for instance, in zone II plot 1 and in zone III plot 2 the % don’t add up to 100%. Correct the % or implement in the text because it is not clear.

The percentage cover of plant species are correct in the table. It was presented percentage cover of plant species in each plot (phytosociological record). In phytosociological analysis according to the Braun-Blanquet method, 100% is the whole surface of the plot (phytosociological record). Percentage cover of plants are not always completely covered distinguished  plots, so it is not 100 percentage cover. We have the same situation in our study areas (plot).

Fig 3 legend: The quantity of Total PM amassed on the leaves of plants. Accumulated?

Corrected to - accumulated

Line 230 as demonstrated in Figure 3. Shown?

Thank you for suggestion. We have corrected the word.

Line 240 depicted in Figure 5C) 4C

Thank you. We made a correction.

Lines 260-261 while the concentration of PM2.5 exceeded the limit (25 μg/m3) in the further distance in Zones I and II. Improve the English of this sentence

Thank you. We have corrected two sentences to make it clearer: It should be noted that in Zone I, the concentration of PM₁₀ exceeded the annual limit (40 µg/m³), whereas in Zones I and II, the concentration of PM_2.5 exceeded the limit (25 µg/m³) at a greater distance from the source.

Line 358 Herbaceous species in this study has a high have

Corrections was made.

Line 369 Moving – Mowing

Corrections was made.

Line 385 in the least effective zone III. - in the least effective zone (zone III).

Thank you. We made a correction.

Line 400

Also, study conducted in Beijing found that different plant species had. Improve the English of this sentence.

Thank you for suggestion. We have changed whole sentence: Moreover, a study carried out in Beijing revealed that various plant species exhibited different capacities to remove PM of diverse sizes, with certain species demonstrating higher efficacy than others.

Line 425.from the road, but for shrubs, there was a significant increase between Zone IV. Delete the underlined comma.

The coma has been deleted.

Line 451 to fully utilise the ability of plants to purify -Improve the English of this sentence.

We improved the English of this sentence - The results of this study suggest that in order to harness the full potential of plants in mitigating PM pollution, it is crucial to gain a comprehensive understanding of PM accumulation within entire plant communities, including spontaneous flora, rather than merely concentrating on individual species

Line 457

This requires Are you referring to two sentences before? It’s not clear please improve it.

After discussion with authors, this sentence was deleted.

Author Response File: Author Response.pdf

Reviewer 2 Report

This manuscript presents the role and impact of different plant layers on near-road PM pollution. The study is interesting regarding multiple plants and their PM removing capacity under urban climatic conditions. However, the study seriously lacks the focus to provide complete information. Its highly recommended to provide full details of the experiment and results. I have the following concerns that need attention from authors to focus / answer.

Major Comments:

1.      Abstract is missing keynote results with quantitative and qualitative aspects and needs to be rewritten from the middle focusing solution / result oriented info.

2.      How much concentration can be retained in the stomata of leaves?

3.      Is there any reference concentration of elements in plant leaves, and What were the total ages of plants under ambient exposure?

4.      How many samples were used for SEM and what was the concentration of heavy metals and PAH in ambient PMs?

5. Authors are unclear about the results and seem confused in mentioning results in Table 1 and Figures. Also required to improve figures and add possible information in table.

6.      The introduction required more literature references and a clear work comparison. Add some health-related information and the toxicity of PMs with references. Highlight the importance of Urban greens for aesthetic pleasure, combat COVID-19 like epidemics and reduce mortality.

https://doi.org/10.1016/j.psep.2022.04.065 ; https://doi.org/10.3390/ijerph192013540 ; https://doi.org/10.1016/j.ecoenv.2022.113356

 

7. Reduce discussion as the first part contains the same information as the introduction. Recommend shifting some text to the introduction part.

Minor:

1.      The title is not appropriate – concise it and remove air pollution as it has a vast meaning

2.      Don’t repeat full text when an abbreviation is inserted, i.e., PM. Double check whole article

3.      Provide a full form of WHO, PM10 and PM2.5 on its first usage

4.      Furnish appropriate reference for line 45-46, 75-76

5.      Line 48-49: How much concentration of PM?

6.      Recommended to add the real image with schematic figure 1 and/or indicate 20 study plots via map

7.      Line 129: Required more clarification – Dry days

8.      Move fig 2 to the results section

9.      A, b and c required caption details for figure 3 and 4

10.   Reproduce figure 6 with clear / readable information and rewrite caption

11.   As discussed earlier (point 6 in major points) – Health and related studies need to place in intro. Improve conclusion and provide limitations and future work.

12.   English needs a careful recheck

Author Response

Our responses are in italic, while in the manuscript as tracked changes.

 

Reviewer 2

 We are grateful for the reviewer’s helpful and constructive comments. In our opinion the research project is innovative. We hope that in our research we managed to study and interpret the most important aspects of the phytoremediation function of roadside spontaneous flora.

This manuscript presents the role and impact of different plant layers on near-road PM pollution. The study is interesting regarding multiple plants and their PM removing capacity under urban climatic conditions. However, the study seriously lacks the focus to provide complete information. Its highly recommended to provide full details of the experiment and results. I have the following concerns that need attention from authors to focus / answer.

Thank you very much to the reviewer for the positive evaluation and very valuable comments. Below are the answers to the questions and corrected parts of the text.

 Abstract is missing keynote results with quantitative and qualitative aspects and needs to be rewritten from the middle focusing solution / result oriented info.

Thank you very much – abstract has been corrected. –

Particulate matter (PM) is a serious air pollutant that poses significant health risks. Despite efforts to reduce air pollution, PM still exists in urbanised areas. One solution to reduce PM concentrations in these areas is through phytoremediation, a process that involves using plants to remove contaminants from the environment. Unfortunately, with urbanisation, green spaces are often replaced by concrete and buildings, making it challenging to implement phytoremediation using traditional landscaping. The solution can be spontaneous flora - plant species that naturally grow in urban conditions without human intervention. A recent study investigated how naturally growing herbaceous plants, shrubs, and trees could accumulate PM on their foliage and reduce air pollution near roadways. The study found significant differences in the accumulation of PM and the sum of Si+Al+Ca on plants across five vegetation zones, with the first two zones (mostly containing herbaceous plants) exhibiting the highest accumulation of total PM, particularly in the region nearest to the roadway. The findings indicated also that the presence of plants has contributed to the reduction of PM concentrations in the air. Summarizing, various plants work together to reduce different fractions of PM, providing a multi-layered approach to tackling air pollution.

         How much concentration can be retained in the stomata of leaves?

Thank you very much for this important question. The concentration of PM that can be retained in the stomata of leaves varies depending on the size and type of particulate matter, as well as the characteristics of the plant species. Generally, smaller particles can penetrate deeper into the leaf tissue and may be retained at higher concentrations, while larger particles may be trapped on the surface of the leaf. Additionally, some plant species may have more efficient mechanisms for capturing and retaining particulate matter, such as hairs or wax layers on the leaf surface. The concentration of PM in the stomata of leaves can also be influenced by environmental factors such as humidity and wind speed. Overall, the exact amount of PM that can be retained in the stomata of leaves is difficult to quantify and may require further research. But in our study we did not measured it. We will try to do it in next study.

Is there any reference concentration of elements in plant leaves, and What were the total ages of plants under ambient exposure?

There are reference values for the concentration of elements in plant leaves, which vary depending on the species and the environment they grow in. These values are used to identify potential nutrient deficiencies or toxicities in plants. However, we did not find reference values for the concentration of PM in plant leaves. Unfortunately, since it is spontaneous flora, it is very difficult to determine its age. Therefore, we did not provide such data in the study.

How many samples were used for SEM and what was the concentration of heavy metals and PAH in ambient PMs?

Thank you very much for this question. These pieces of information are in section 2.7 of the article:

For the SEM analysis, dried filter papers from the water extraction were selected. Filter papers with a pore size of 10 µm and the highest amount of PM residues from water extraction were chosen. Five random areas were scanned at 300x magnification for each sample... The content of heavy metals was too low to be assessed reliably. The SEM technique is not suitable for the quantitative analysis of trace elements in these types of samples. We know that measuring PAHs in airborne PM would provide valuable insights, but unfortunately, we did not have the appropriate equipment to measure them in this study.

Authors are unclear about the results and seem confused in mentioning results in Table 1 and Figures. Also required to improve figures and add possible information in table.

Thank you very much for this comment. We have corrected the Table 1, and added more descriptions of the information.

        The introduction required more literature references and a clear work comparison. Add some health-related information and the toxicity of PMs with references. Highlight the importance of Urban greens for aesthetic pleasure, combat COVID-19 like epidemics and reduce mortality. https://doi.org/10.1016/j.psep.2022.04.065 ; https://doi.org/10.3390/ijerph192013540 ; https://doi.org/10.1016/j.ecoenv.2022.113356

       Thank you very much for this comment. We have added some health related information from suggested articles.

 Reduce discussion as the first part contains the same information as the introduction. Recommend shifting some text to the introduction part.

Thank you. You are right. Some information from discussion were reduced and shifted.

 

1. The title is not appropriate – concise it and remove air pollution as it has a vast meaning

Thank you for this suggestion. We have corrected the title.

2. Don’t repeat full text when an abbreviation is inserted, i.e., PM. Double check whole article

We have corrected particulate matter to PM in whole text.

3. Provide a full form of WHO, PM10 and PM2.5 on its first usage

Thank you. We provided the full forms.

4. Furnish appropriate reference for line 45-46, 75-76

Thank you, we added the reference for this sentences.

5. Line 48-49: How much concentration of PM?

Thank you. We have corrected the information.

6. Recommended to add the real image with schematic figure 1 and/or indicate 20 study plots via map

       Thank you very much for this comment. We know that goof figures should be ridable by the readers. But in our opinion adding plots would be misleading, so we decided to not add them.

7. Line 129: Required more clarification – Dry days
8. Move fig 2 to the results section

Thank you very much for this comment but we think that tis fig. Should be in this section.

9. A, b and c required caption details for figure 3 and 4

Thank you very much for this comment. Additional information has been add to the caption.

10. Reproduce figure 6 with clear / readable information and rewrite caption

        We have reproduced figure 6. We hope that now is more readable, and we have rewidened caption.

11. As discussed earlier (point 6 in major points) – Health and related studies need to place in intro. Improve conclusion and provide limitations and future work.

       A discussed earlier related studies has been added. We have also improved limitations and added the future work.

12. English needs a careful recheck

Thank you very much for this comment. English was checked again from the native speaker.

Reviewer 3 Report

Line 2: Authors may replace “protection of” from the title and write a suitable word there.

Line 40: Authors explain what “Orientation”

Line 63-64: to use naturally occurring plants in a given area or the spontaneous flora, i.e., the plant species that can grow naturally in urban conditions without human intervention

Line 77: Why “barriers” is mentioned?

Line 142: 10 & 2.5 UNIT?

Line 228: remove “particles”

The spelling of herbaceous be changed

Line 457-458: “This requires careful planning and management of urban green spaces and ongoing monitoring and research to understand their impacts better and optimise their effectiveness

Authors justify that if planting them requires planning, then, how does it validate that these are spontaneous flora that has been planted without human intervention?

 

 

Author Response

Our responses are in italic, while in the manuscript as tracked changes.

 

Reviewer 3

 We are grateful for the reviewer’s helpful and constructive comments. In our opinion the research project is innovative. We hope that in our research we managed to study and interpret the most important aspects of the phytoremediation function of roadside spontaneous flora.

Thank you very much for the positive evaluation and very valuable comments. Below are the answers to the questions and corrected parts of the text.

Line 2: Authors may replace “protection of” from the title and write a suitable word there.

Thank you very much for this comment. We have changed protection to mitigation.

Line 40: Authors explain what “Orientation”

Thank you for this suggestion. It was mistake – we have deleted this word from manuscript.

Line 63-64: to use naturally occurring plants in a given area or the spontaneous flora, i.e., the plant species that can grow naturally in urban conditions without human intervention

Thank you very much for this comment. We have changed the sentences to make it more clear.

Line 77: Why “barriers” is mentioned?

Thank you very much of this suggestion. After discussion with authors word barriers was deleted.

Line 142: 10 & 2.5 UNIT?

Thank you. We added the units.

Line 228: remove “particles”

The word particles has been deleted.

Line 457-458: “This requires careful planning and management of urban green spaces and ongoing monitoring and research to understand their impacts better and optimise their effectiveness. Authors justify that if planting them requires planning, then, how does it validate that these are spontaneous flora that has been planted without human intervention?

We agree with the reviewer. We have deleted this sentence.

 

Reviewer 4 Report

Comments and suggestions are included in the file attached.

Comments for author File: Comments.pdf

Author Response

Our responses are in italic, just below the reviewers’ comments. Changes in the manuscript as tracked changes.

 

Reviewer 4

 We are grateful for the reviewer’s helpful and constructive comments. In our opinion the research project is innovative. We hope that in our research we managed to study and interpret the most important aspects of the phytoremediation function of roadside spontaneous flora.

 

Thank you very much for very important comments and suggestions.

 

 

 Line 2-3. Improve the title! As it is now, it is as we want “to protect the particulate matter”… A suggestion could be: “ The protective role of spontaneous flora against particulate matter air pollution from ….”

Thank you very much for this comment. The title has been changed.

 

Line 38 and 42. Keep only PM (it is already explained a few lines before)

We have changed to PM in all text.

 

Line 39. Omit „,‟ …speed and turbulence,

The changes has been done in the text.

 

Line 80. replace „trace elements‟ à TE

The corrections has been done.

 

Line 98. …was represented

We have changed the word to – located. We think it fits more than represented.

 

Line 99 and 101. The unpaved road that is mentioned in line 99 is „the gravel-sand road‟ that is mentioned in line 101?

Yes. We have changed it to unpaved road to be more clear.

 

Line 103. „…five green spaces, …‟ you mean the 5 zones? Make it clear in the text.

Thank you. We corrected whole sentence.

 

Figure 1. Change Zone 1, 2,3… to Zone I, II, III,… (as it is in the text)

Thank you very much, we have changed the figure 1.

 

Lines 110-111. Change into à …located in the above-mentioned five zones

Thank you for suggestion. We have changed as you recommended.

Lines 111-112. The meaning of the sentence is not clear. There are squares 4x4m (16m2) that are 2m away one from the other?

Thank you very much for this comment. The whole sentence has ben rewritten. Phytosociological records of 1 m² were located at a distance of 2 m from each other within every zone.

 

Line 116. …maximum height of 2 meters. This is correct?

Thank you for suggestion. We have corrected in the text the height of the trees.

 

Line 120. Add space 2.3. Sample

We added space.

 

Line 121. Four biological replicates of the plants and leaves were harvested….

Thank you. We changed whole sentence.

 

Line 140. Add space. …(wPM). The…

We added space.

 

Line 157 and 165. Add spaces after 2.6. and 2.7.

We added space.

 

Line 178. Provide the definition of EDX

The definition was provided into the text.

 

Line 182. Correct “…was utilized…”

Thank you. We corrected the text.

 

 

Line 190. Give the definitions: “ …using …..(BSE) and ….(EDX) mapping…” (as mentioned in the guidelines for manuscript preparation)

We added necessary information.

 

Line 191. Zone III

Thank you. We made a correction.

 

Line 193. Add space. 3.1. Flora

Thank you. We made a correction.

 

Line 196. Table 1.

Thank you. We made a correction.

 

Line 201, 202, 203, 204 and 205. Zones

Thank you for your comment. We made corrections in whole text.

 

Line 203. Give the complete genus of S. virgaurea

Thank you for your comment. We gave a complete genus in the text.

 

Line 205. Table 1.

We made a correction.

Line 207. Table 1. and Zones

 

Table 1. in the table is mentioned (sm), BUT at the end of the table Line 209 is (sn). Also try to change the size Font in the columns in order to have the scientific name of the plant and the (s)/(sm),… in one line.

We made a correction. About the font size we hope that it wil be corrected during the editing proces.

Line 212. Add space. 3.2. PM

We made a correction.

Line 220. Zone IV

We made a correction.

 

Line 223. Figure 3.

We made a correction.

 

Line 227. à particulate matter PM

We made a correction.

 

Line 250. Figure 4.

We made a correction.

 

Figure 4 à line 252. “The black letters indicate….” Because there are a couple of black letters, in order to make clear where to look: “The black letters (above the columns) indicate….”

Thank you for suggestion. We corrected as you mentioned.

 

Figure 5. In the Figure is written “annual/norm”. Give also the definition of what is this.

The information has been added.

 

Line 279. …two types groups

We made a correction.

 

Line 285. Zones (I-III)…

We made a correction.

 

Line 289. Add space. 3.5. Semi

We made a correction.

 

Line 291. Figure 8 7

We made a correction.

 

Line 292. Figure 7. Also, give the definition of EDX

Thank you for this suggestion. We added the definition to the text.

 

Page 12-paragraph 3 (One of the main..) *If possible, add a few more related references that do not include any of the authors of this article.

In our view, the articles authored by the contributors of this manuscript are highly valuable and relevant to the topic at hand. Neglecting to acknowledge their contributions and findings would not only be a disservice to the authors, but also a significant gap in the literature review of this article. Therefore, we strongly recommend including these articles and citing them appropriately to provide a comprehensive and well-informed analysis of the subject matter.

 

Line 301. Zone I…

Line 303. Zones II and III…

Line 305. Zones IV…

Line 307. Zones IV…

Line 349. …Zones I and II…

In all lines we made a correction.

 

Line 355. “…lack of water and other challenges, while…”

We made a correction.

 

Lines 357-8. “…in filtering air pollution before it reaches cleaner air.” Perhaps better to change it to: …before it spreads further

We made a correction.

 

 

Lines 358-9. “…has a high accumulation of PM due to their morphology and canopy structure,…”

è …presents a high accumulation ability of PM… We made a correction.

 

è “canopy” is a term used for trees and/or shrubs. – We corrected to the layer.

 

Line 363. “…the dense and porous plant filter in our study…” What do you mean? What filter? Improve the sentence

We rewidened whole sentence to make it more clear

Line 369. Correct: “Moving…”

We made a correction.

 

Line 371. “…and reduces the surface area on which they can accumulate pollutants”

Perhaps change it to: “and reduces the surface area on which pollutants can be accumulated”

We made a correction.

 

Line 378. Zone IV

We made a correction.

 

Line 379. “…types, trees only present in the fifth zone accumulated…”

è “…types, trees, which were only present in the fifth zone, accumulated…

We made a correction.

 

Line 385. Zone III

We made a correction.

 

Line 391. “…that herbaceous plants filtered the polluted air before it could

Filtered could have been used for NOx, SO4-, etc. gaseous pollution that could be absorbed into the plant body. Here the particles stay on the plant surface.

Probable change to: “that herbaceous plants act as a barrier of the polluted air before it could…”

Thank you very much for suggestion. We made a correction.

 

 

Line 393-4. “…on shrubs and tree leaves, but this could be re-suspended by wind and rain”

à “…on shrubs and tree leaves due to the re-suspension by wind and rain”

We made a correction.

 

Line 396. …no hardened surfaces areas

We made a correction.

 

Line 400. Also study conducted in Beijing also found

We made a correction.

 

Line 409. “…this study….” Change „this‟ into our

We made a correction.

 

Lines 405 and 410. “plant types…” The word „types‟ is used to indicate the different plant species? or the herbs/shrubs/trees? Make it clear.

We made a correction to species.

 

Line 414. “… was observed for another type of PM, immobilised …” Another type?? You mean the wPM or something else? It is not clear!

Yes, we corrected the sentence to make it more clear.

 

Line 417. “…lipophilic PM …”. The term lipophilic is referred to the wPM?

Yes, we corrected the sentence to make it more clear.

 

 

Lines 414-418. Taking into consideration the above, improve the text. It is confusing for the reader.

We have corrected the sentences in this part to make it clear for the readers.

 

Line 436. …IV and V Zones…

We made a correction.

 

[5. Conclusions] **Also include, in brief, the findings of the study (already mentioned in the Discussion part), before the text you already have.

We made some changes in the conclusion part.

 

Line 451. “…this study indicate that, to fully ….”

We corrected whole sentence.

 

 

Line 456. “… team and fulfill …”

We made a correction.

 

Line 458. “... and research in order to better understand their impacts better and optimise ….”

We have deleted this sentence.

 

Line 464. "undesirable".

We made a correction.

Lines 540 and 577. à put the plant scientific names in italics.

We putted scientific names in italics as suggested.

Round 2

Reviewer 2 Report

Paper is greatly improved. Minor points still need revision.

Lines 18-19: Only provide your study results; unclear, need rewrite.

The abstract still need to be improved - specifically quantitative summary. See example to follow: https://doi.org/10.3390/su142013374; https://doi.org/10.3390/horticulturae8111046

Line 46-48: Highlight / provide concern of developing PM pollution in cities, i.e., indo-gangentic plain have major concerns of increasing PM pollution https://doi.org/10.1016/j.atmosenv.2022.119472, also Beijing and some other heavy traffic cities have air pollution issue.

Line 79-80: Not agree. Remove or improve your claim to limited studies available on this topic. See section 3 of https://doi.org/10.1016/j.jenvman.2021.113860

The captions of figures need to be self explanatory. What is A to E inside charts?

Double check Figure 5, A to D points are annual concentrations? if not why compared with annual norm values, instead provide 24-h average.

Line 334-339: Looks not logical text with link to previous or next paragraph. Remove or short with logical flow.

Author Response

Our responses are in italic, just below the reviewers’ comments. A new/revised text is in bold font in this response, while in the manuscript as tracked changes.

Reviewer 2

 We are grateful for the reviewer’s helpful and constructive comments. We hope that in our research we managed to study and interpret the most important aspects of the phytoremediation function of roadside spontaneous flora. Thank you very much for careful read of our manuscript. In next lines we added the information about corrections according to the comments.

lines 18-19: Only provide your study results; unclear, need rewrite.

We agree with this comment. This part was cancelled and rewritten

The abstract still need to be improved - specifically quantitative summary. See example to follow: https://doi.org/10.3390/su142013374; https://doi.org/10.3390/horticulturae8111046

Thank you very much for this suggestion. We have rewritten this part to make it mre similar to suggested articles.

Line 46-48: Highlight / provide concern of developing PM pollution in cities, i.e., indo-gangentic plain have major concerns of increasing PM pollution https://doi.org/10.1016/j.atmosenv.2022.119472, also Beijing and some other heavy traffic cities have air pollution issue.

Thank you very much for this suggestion. We added new sentence about ino-gangetic plain. Also we added relevant suggested citation.

Line 79-80: Not agree. Remove or improve your claim to limited studies available on this topic. See section 3 of https://doi.org/10.1016/j.jenvman.2021.113860

Thank you very much. We arge agree with the comment. We corrected the sentence.

The captions of figures need to be self explanatory. What is A to E inside charts?

We are thinking that all the necessary information are in the captions. Please read carefully. There was no suggestions from three other reviewers so we think everything is clear.

Double check Figure 5, A to D points are annual concentrations? if not why compared with annual norm values, instead provide 24-h average.

We are completely agree with this comment. Annual norms and fragment about the has been deleted from the manuscript.

Line 334-339: Looks not logical text with link to previous or next paragraph. Remove or short with logical flow.

We agree with the comment. We deleted this fragment.