Spatial Distribution of Vegetation on Stream Bars and the Riparian Zone Reflects Successional Pattern Due to Fluid Dynamics of River
Round 1
Reviewer 1 Report
The manuscript, entitled “Spatial Distribution of Vegetation on Stream Bars and Riparian Zone Reflects Successional Pattern Due to Fluid Dynamics of River” is to analyze the change in geomorphology caused by the flow characteristics of water in rivers and the response of vegetation to it. The topic falls within the scope of the Journal.
I recommend a following major revision before the manuscript is ready for publication.
1, In this manuscript., the spatial distribution of vegetation on stream bars and riparian zone was described in detail, but the quantitative analysis on fluid dynamics of stream Bars and Riparian Zone was insufficient. It is suggested to provide additional explanation.
2. Please show the time of field investigation in Section 2.2.
3. Please annotate the flow direction on each picture in Figure 2.
4. It is suggested to use data (such as satellite or unmanned aerial vehicle remote sensing data) from multiple periods to illustrate the laws of space-time change of vegetation on stream bars and riparian zone and fluid dynamics of river.
Author Response
Response to reviewer’s comments
Reviewer 1
Open Review
(x) I would not like to sign my review report
( ) I would like to sign my review report
Quality of English Language
( ) English very difficult to understand/incomprehensible
( ) Extensive editing of English language and style required
( ) Moderate English changes required
( ) English language and style are fine/minor spell check required
(x) I am not qualified to assess the quality of English in this paper
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Yes |
Can be improved |
Must be improved |
Not applicable |
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Does the introduction provide sufficient background and include all relevant references? |
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Are all the cited references relevant to the research? |
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Is the research design appropriate? |
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Are the methods adequately described? |
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Are the results clearly presented? |
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Are the conclusions supported by the results? |
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Comments and Suggestions for Authors
The manuscript, entitled “Spatial Distribution of Vegetation on Stream Bars and Riparian Zone Reflects Successional Pattern Due to Fluid Dynamics of River” is to analyze the change in geomorphology caused by the flow characteristics of water in rivers and the response of vegetation to it. The topic falls within the scope of the Journal.
I recommend a following major revision before the manuscript is ready for publication.
1, In this manuscript., the spatial distribution of vegetation on stream bars and the riparian zone was described in detail, but the quantitative analysis of fluid dynamics of stream Bars and Riparian Zone was insufficient. It is suggested to provide additional explanation.
☞ We did not analyze fluid dynamics. In order to reinforce this problem, this study was conducted by adding riparian vegetation data that well reflects the difference in hydrological disturbance and comparing the results obtained from the stream bars with the results.
In addition, our study focused on revealing the spatial distribution and succession of vegetation. Instead, the literature of other researchers was referenced for its interpretation. Most of such literature focused on mathematical interpretation through model experiments. Therefore, we focused on obtaining field data supporting such interpretations.
Lines 369 – 461.
- Please show the time of field investigation in Section 2.2.
☞ We added the time of field investigation. Line 141.
- Please annotate the flow direction on each picture in Figure 2.
☞ We indicated the direction of the water flows with arrows. Figure 2.
- It is suggested to use data (such as satellite or unmanned aerial vehicle remote sensing data) from multiple periods to illustrate the laws of space-time change of vegetation on stream bars and riparian zone and fluid dynamics of the river.
☞ This area is close to the borderline area where South and North Korea face each other, and taking UAV photography is prohibited, and it is impossible to obtain remote sensing data with high resolution. Therefore, we tried to evaluate the disturbance regime by space based on topographical differences such as height from the water surface or distance from the waterway and to explain fluid dynamics and vegetation dynamics by connecting them to the development stage of vegetation according to topographical differences. Instead, unlike other regions in Korea, artificial interference was not severe, so the vegetation conservation state was good, resulting in meaningful results.
Author Response File: 
Author Response.docx
Reviewer 2 Report
Comments to paper
63 this occurs only in a colonization process by pioneer vegetation (tiny seeds)
110 lowland reach?
112 remain little? Are scarce? Few remain?
112 gravel bars: please define size of what you call gravel. From figure 2 I see boulders also.
120-122 are these the results of the paper, or methods?
128-130 are these the results of the paper?
135 levees are mentioned, and thus, the river channel is artificially constricted!
137 which numbers are for each reach and for bars and riparian zones?
138 I suggest considering different names, such as mountain gravel bed river, or a lowland river reach, instead of upstream or downstream.
158 Figure 3 contains information about gravel and sand bars that are not commented on text and I consider important to explain their colonization process by vegetation:
1) in the gravel bar l its upstream part of the current is low and is made up of riparian pioneer species resistant to the current (Salix gracilystila) followed by soil-forming species (Juglans madshurica and Cornus controversa), while its downstream part is high (it has accumulated sediments and is covered by mature terrestrial species (pine), which suggests that the gravel bar advances upstream.
2) on the contrary, on the sand bar from lowland reach, the highest part of the bar is located at its upstream end and is colonized by mature willows (capturing sediments), while its lower downstream end is at water level covered by aquatic helophytes. This indicates that the bar is stable or moving/enlarging downstream.
3) on the estuary, sand bars are similar in composition and structure to those of the river, but arranged inversely, indicating the force of the tides.
257 Diversity: as expected: mature communities with highest diversity and pioneer with lowest!
293-294 Salix gracilistyla is not herbaceous! Is a pioneer species that fixes gravel bar by its root system, and the roughness produced by its stem and branches it favors the deposit of fines and therefore creates soil. I believe that it is more illustrative to define the functioning of each type of community than its mere composition.
323 the riparian dynamics should have been verified by means of a comparative analysis of aerial photos from different years. Are the results presented stable, or do they correspond to a phase of a temporary change process?
363-423 I will eliminate this entire part of the discussion, as it is speculative regarding the results presented. It is a paper, not a treatise on riparian vegetation!
342-347 To explain the results (basically descriptive of vegetation distribution) it is necessary to present these hydrological data: What is the flow regime of these rivers? What are the magnitude, frequency and duration of peak flow events? Has flow regime changed in time?
497-500 This is not a conclusion of this paper!! No data of stream power of these reaches have been presented! You cannot conclude this!
510-512 you may suggest or hypothesize that young pine forest community will evolve with time into a mature one, and thus the bar and riparian structure will be simplified.
It is a good paper with good vegetation data and well sampled. The approach of three scenarios with different substrates is of interest and the results are consistent. However, it should be improved in order to have greater consistency in the approaches and be completed with physical and hydrological data to support a large part of the discussion, and above all, reduce the conclusions to the facts that come exclusively from the results. Also, English language may be improved.
The description of the studied reaches should be completed with hydromorphology data: channel width, sinuosity, substrate grain size, river slope, Flow regime (data from near by Gaugin stations), floods magnitude, frequency and duration, stream power. Also, it would be important to describe the recent changes in the river sections (with comparative analysis of aerial photos and flows in the last decades). With these data, a large part of the discussion could be justified, or otherwise reduced.
Author Response
Response to reviewer’s comments
Reviewer 2
Open Review
( ) I would not like to sign my review report
(x) I would like to sign my review report
Quality of English Language
( ) English very difficult to understand/incomprehensible
( ) Extensive editing of English language and style required
(x) Moderate English changes required
( ) English language and style are fine/minor spell check required
( ) I am not qualified to assess the quality of English in this paper
|
Yes |
Can be improved |
Must be improved |
Not applicable |
|
|
Does the introduction provide sufficient background and include all relevant references? |
(x) |
( ) |
( ) |
( ) |
|
Are all the cited references relevant to the research? |
(x) |
( ) |
( ) |
( ) |
|
Is the research design appropriate? |
(x) |
( ) |
( ) |
( ) |
|
Are the methods adequately described? |
( ) |
( ) |
(x) |
( ) |
|
Are the results clearly presented? |
( ) |
(x) |
( ) |
( ) |
|
Are the conclusions supported by the results? |
(x) |
( ) |
( ) |
( ) |
Comments and Suggestions for Authors
Comments to paper
63 this occurs only in a colonization process by pioneer vegetation (tiny seeds)
☞ Yes. Stream bars and riparian zones where this study was conducted are disturbed intensively as well as frequently, making it difficult for vegetation of the late successional stage with large seeds to establish.
110 lowland reach?
☞ Yes. You are right. We revised the part. Line 111.
112 remain little? Are scarce? Few remain?
☞ In the name of river management in preparation for flooding, the bottom of the river is dredged every year, so there are few stream bars left. Therefore, we want to maintain the status quo.
112 gravel bars: please define size of what you call gravel. From figure 2 I see boulders also.
☞ Based on the particle size of the substrate, the boulder is right. However, when referring to stream bars in hydro-ecology, the bars were referred to as gravel bar or sand bar, and we divided bars into gravel bar and sand bar.
120-122 are these the results of the paper, or methods?
☞ This part corresponds to the site description.
128-130 are these the results of the paper?
☞ This part corresponds to the site description.
135 levees are mentioned, and thus, the river channel is artificially constricted!
☞ Yes, in regions where rice is used as a staple food, most rivers artificially created embankments, and their widths are reduced.
137 which numbers are for each reach and for bars and riparian zones?
☞ We revised the sentence to reduce misunderstanding.
138 I suggest considering different names, such as mountain gravel bed river, or a lowland river reach, instead of upstream or downstream.
☞ We revised them by accepting reviewer’s comments.
158 Figure 3 contains information about gravel and sand bars that are not commented on text and I consider important to explain their colonization process by vegetation:
1) in the gravel bar l its upstream part of the current is low and is made up of riparian pioneer species resistant to the current (Salix gracilystila) followed by soil-forming species (Juglans madshurica and Cornus controversa), while its downstream part is high (it has accumulated sediments and is covered by mature terrestrial species (pine), which suggests that the gravel bar advances upstream.
2) on the contrary, on the sand bar from lowland reach, the highest part of the bar is located at its upstream end and is colonized by mature willows (capturing sediments), while its lower downstream end is at water level covered by aquatic helophytes. This indicates that the bar is stable or moving/enlarging downstream.
3) on the estuary, sand bars are similar in composition and structure to those of the river, but arranged inversely, indicating the force of the tides.
☞ We explained such contents in 4.2. Formation process of stream bars and vegetation succession section but didn’t explain in detail. So, we reinforced the part by accepting reviewer’s comments.
257 Diversity: as expected: mature communities with highest diversity and pioneer with lowest!
☞ Yes. Through analysis of diversity, we also confirmed the difference in fluid dynamics depending on spatial differences, that is, topographical differences in stream bars and riparian zones, and further, the difference in successional stages of vegetation due to such differences.
293-294 Salix gracilistyla is not herbaceous! Is a pioneer species that fixes gravel bar by its root system, and the roughness produced by its stem and branches it favors the deposit of fines and therefore creates soil. I believe that it is more illustrative to define the functioning of each type of community than its mere composition.
☞ Yes, you are right. Salix gracilistyla is not herbaceous plant but a shrub. We explained such phenomena in 4.2. Formation process of stream bars and vegetation succession section.
323 the riparian dynamics should have been verified by means of a comparative analysis of aerial photos from different years. Are the results presented stable, or do they correspond to a phase of a temporary change process?
☞ This area is close to the borderline area where South and North Korea face each other, and taking UAV photography is prohibited, and it is impossible to obtain remote sensing data with high resolution. Therefore, we tried to evaluate the disturbance regime by space based on topographical differences such as height from the water surface or distance from the waterway, and to explain fluid dynamics and vegetation dynamics by connecting them to the development stage of vegetation according to topographical differences. Instead, unlike other regions in Korea, artificial interference was not severe, so the vegetation conservation state was good, resulting in meaningful results.
363-423 I will eliminate this entire part of the discussion, as it is speculative regarding the results presented. It is a paper, not a treatise on riparian vegetation!
☞ We revised this part greatly by accepting reviewer’s comments. Lines 369-461. However, most of the contents mentioned here are necessary to interpret the formation process of stream bars and the vegetation succession that occurs in response to it, and I’d like to keep them because they explain the characteristics of the succession type that occurs here. However, the contents of large woody debris, which are less directly related to the research results, were deleted.
342-347 To explain the results (basically descriptive of vegetation distribution) it is necessary to present these hydrological data: What is the flow regime of these rivers? What are the magnitude, frequency and duration of peak flow events? Has flow regime changed in time?
☞ Yes, you are right. So, we added the following contents: In Korea, which belongs to the monsoon climate zone in Asia, more than 70% of rainfall is concentrated from July to August during rainy season and September during typhoon season. Moreover, as a mountainous country, the water level fluctuates so much that the coefficient of flow fluctuation reaches 300 to 700 as Korea has a steep river slope. Lines 438 - 442.
However, our study focused on revealing the spatial distribution and succession of vegetation. Instead, the literature of other researchers was referenced for its interpretation. Most of such literature focused on mathematical interpretation through model experiments. Therefore, we focused on obtaining field data supporting such interpretations.
497-500 This is not a conclusion of this paper!! No data of stream power of these reaches have been presented! You cannot conclude this!
☞ We added collectable hydro-morphological data in 2.1 Study area section by accepting reviewer’s comments. Lines 124 – 128.
510-512 you may suggest or hypothesize that young pine forest community will evolve with time into a mature one, and thus the bar and riparian structure will be simplified.
☞ We explained the phenomenon as the followings: This successional process stage on stream bars consists of an early stage in which the herbaceous plants dominate and a settlement stage in which shrubs or shade intolerant trees dominate. Succession do not reach the late successional stage such as mature deciduous broad-leaved forests in the sand bars or gravel bars located in the center of the dynamic river. In Korea, which belongs to the monsoon climate zone in Asia, more than 70% of rainfall is concentrated from July to August during rainy sea-son and September during typhoon season. Moreover, as a mountainous country, the water level fluctuates so much that the coefficient of flow fluctuation reaches 300 to 700 as Korea has a steep river slope. In other words, it means that rivers experience such strong flood disturbances. Lines 433-442
It is a good paper with good vegetation data and well sampled. The approach of three scenarios with different substrates is of interest and the results are consistent. However, it should be improved in order to have greater consistency in the approaches and be completed with physical and hydrological data to support a large part of the discussion, and above all, reduce the conclusions to the facts that come exclusively from the results. Also, English language may be improved.
☞ In order to reinforce this problem, this study was conducted by adding riparian vegetation data that well reflects the difference in hydrological disturbance and comparing the results obtained from the stream bars with the results.
In addition, as was mentioned above, our study focused on revealing the spatial distribution and succession of vegetation. Instead, the literature of other researchers was referenced for its interpretation. Most of such literature focused on mathematical interpretation through model experiments. Therefore, we focused on obtaining field data supporting such interpretations.
The description of the studied reaches should be completed with hydromorphology data: channel width, sinuosity, substrate grain size, river slope, Flow regime (data from near by Gaugin stations), floods magnitude, frequency and duration, stream power. Also, it would be important to describe the recent changes in the river sections (with comparative analysis of aerial photos and flows in the last decades). With these data, a large part of the discussion could be justified, or otherwise reduced.
☞ We added collectable hydro-morphological data in 2.1 Study area section by accepting reviewer’s comments. Lines 224 – 228. However, such information was built centering on large rivers in South Korea, and the area where this study was conducted is close to the border area facing South Korea and North Korea, so detailed data are particularly insufficient.
In addition, this area is close to the borderline area where South and North Korea face each other, and taking UAV photography is prohibited, and it is impossible to obtain remote sensing data with high resolution. Therefore, we tried to evaluate the disturbance regime by space based on topographical differences such as height from the water surface or distance from the waterway, and to explain fluid dynamics and vegetation dynamics by connecting them to the development stage of vegetation according to topographical differences. Instead, unlike other regions in Korea, artificial interference was not severe, so the vegetation conservation state was good, resulting in meaningful results.
Round 2
Reviewer 1 Report
The manuscript, entitled “Spatial Distribution of Vegetation on Stream Bars and Riparian Zone Reflects Successional Pattern Due to Fluid Dynamics of River” is to analyze the change in geomorphology caused by the flow characteristics of water in rivers and the response of vegetation to it. The topic falls within the scope of the Journal.
The revised version of the manuscript (ijerph-2252797-peer-review-v2) has been modified according to the reviewers’ comments. I recommend accepting the manuscript (ijerph-2252797-peer-review-v2) after minor revision.
Author Response
Response to reviewer’s comments
Dear Reviewer,
Thank you for your kind consideration.
We checked carefully our manuscript by accepting reviewer’s comment as below.
Sincerely yours.
C.S. Lee
The manuscript, entitled “Spatial Distribution of Vegetation on Stream Bars and Riparian Zone Reflects Successional Pattern Due to Fluid Dynamics of River” is to analyze the change in geomorphology caused by the flow characteristics of water in rivers and the response of vegetation to it. The topic falls within the scope of the Journal.
The revised version of the manuscript (ijerph-2252797-peer-review-v2) has been modified according to the reviewers’ comments. I recommend accepting the manuscript (ijerph-2252797-peer-review-v2) after minor revision.
☞ Thank you for your kind consideration. We checked carefully our manuscript by accepting reviewer’s comment.
Author Response File: Author Response.docx
