Vegetation Cover Variation in Dry Valleys of Southwest China: The Role of Precipitation

Round 1

Reviewer 1 Report (Previous Reviewer 1)

The authors have revised the manuscript accordingly, and I recommend accepting it. 

Author Response

Many thanks to the reviewer for their recognition of our research work and manuscript. 

Also, according to the suggestion of the academic editor and reviewers, that this manuscript should undergo extensive English revisions, we have addressed this issue during revision with the editing services listed at https://www.mdpi.com/authors/english, corrected the manuscript English writing so a reviewer can read it through without issue. More detail changes of this manuscript please check the last revised manuscript with changes marked upload the journal submit system.

Reviewer 2 Report (Previous Reviewer 3)

The work is greatly improved and seemed fine for me, but you have lost reference in text for article #51. 

I do not insist, but it is better to check English one more time. For example:

line 27: "significant increasing trend were reported" -- > "trend was" or "trends were"

line 474: "which was probably caused by the large-scale ecological restoration project the implemented by the government." --> "project implemented"

 

Author Response

Many thanks to the reviewer for their recognition of our research work. Response to comments:

(1) The work is greatly improved and seemed fine for me, but you have lost reference in text for article #51.  

Response: Thanks very much for the suggestions. We have carefully checked the reference and found that the article # 51 has been lost in the previous manuscript. In the new submitted manuscript, the reference #51 has been added in the proper place in Line 455 in the file“revision with changes marked”. 

(2) I do not insist, but it is better to check English one more time. For example: line 27: "significant increasing trend were reported" -- > "trend was" or "trends were"; line 474: "which was probably caused by the large-scale ecological restoration project the implemented by the government." --> "project implemented"

Response: Thanks for pointing out the English problems in the previous manuscript. According to the suggestion of the academic editor and reviewers' suggestion, that this manuscript should undergo extensive English revisions, we have addressed this issue during revision with the editing services listed at https://www.mdpi.com/authors/english, for correcting the English so a reviewer can read it through without issue. More detail changes of this manuscript please check the last revised manuscript upload the journal submit system.

Reviewer 3 Report (New Reviewer)

The manuscript is extremely difficult to read because only a markdown version has been provided.

The text needs some English edition. Many sentences are difficult to understand. The paper should not be published without extensive language editing.

MODIS is the abbreviation and shall be written with capital letters.

The major problem with the study is that it considers only the annual amount of precipitation. Vegetation is likely sensitive to seasonal variations in precipitation as well. Precipitation climatology is not properly described in the paper. It is known however that this corner of the world has moist and dry seasons. I would recommend to investigate in more details links between seasonality of precipitation and vegetation indices.

Author Response

Thanks very much for your sincere suggestions and comments. 

（1）The manuscript is extremely difficult to read because only a markdown version has been provided.

Response：Sorry for the difficulties that we have missed to upload the revised manuscript. We have uploaded all the marked revised-version and no-maeked revised-version.

（2）The text needs some English edition. Many sentences are difficult to understand. The paper should not be published without extensive language editing.

Response: As you suggested, the new manuscript has been sent to MDPI author services for Professional English Editing and the certification for English editing is listed as follows.

(3) MODIS is the abbreviation and shall be written with capital letters.

Response: We have also rewritten “Modis” to “MODIS” in the abstract (line 18 in the manuscript of revision with changes marked ), which in the capital letters, and thanks again for pointing this.

 (4) The major problem with the study is that it considers only the annual amount of precipitation. Vegetation is likely sensitive to seasonal variations in precipitation as well. Precipitation climatology is not properly described in the paper. It is known however that this corner of the world has moist and dry seasons. I would recommend to investigate in more details links between seasonality of precipitation and vegetation indices.

Response: As noted in the review comments, the links between seasonality of precipitation and vegetation indices are also very important. In the dry valleys, usually more than 80% of annual precipitation falls in the wet period from May to October, and mainly from summer, and the vegetation cover will maintain a relatively high level in the wet period (Zhang, R.Z. The dry valley of the Hengduan Mountains Regions. Science Press: Beijing, China,1992.). Meanwhile, only less than 20% of the annual precipitaion was in the dry period from November to April next year, and the vegetation indices in this period were usually very low due to the lack of water. Therefore, based on the significant difference law of dry and wet season rainfall distribution in arid valley, this manuscript focused on the effect of annual precipitation on the dynamics in annual FVC and has not investigated the seasonality of precipitation and vegetation indices. Of course, we agree to the suggestion that investigate in more detail’s links between seasonality of precipitation and vegetation indices. In fact, we have made positioning observation of long-term vegetation change in the field soil and water conservation monitoring station in the dry-hot valley. In the future, we will combine the NDVI data and the measured data of the sample plot to reflect the influence of the seasonal changes of rainfall and vegetation coverage.

This manuscript is a resubmission of an earlier submission. The following is a list of the peer review reports and author responses from that submission.

Round 1

Reviewer 1 Report

This paper discussed a valuable topic of how vegetation changes in hot, dry valleys. Although authors have made some valuable attempts, the paper still need major revisions. The details are as follows:

1.     Abstract: Abstract is not good enough. The scientific question was not well summarized, and there was no description of the research methodology in abstract. Some acronyms (e.g. DVR) did not show full names.

 

2. Introduction: I suggest separating the words about the effects of precipitation and hydropower projects. In addtion, I discourage authors from writing words such as "This study is probably the first report on dynamics..." , which I think should be avoided.

 

3. Methods and Results:

3.1 In Table 1, references should be added;

 

3.2 There is an error in the text after Figure 2: "****** were interpreted based on 2m GF-1 and GF-2..." In fact, Gaofen 2 has a panchromatic resolution of 1m.

 

3.3 The presentation in Figure 3 is not good enough. I think several small maps should be listed to show the land cover inside the valley.

 

3.4 Section 2.3, the author should further state clearly what method is used to identify the influencing factors of FVC.

 

3.5 Table 4, I think Table 4 can be removed.

 

3.6 Figure 5. The resolution in Figure 5 is too low, please change it clearer.

 

3.7 Figure 6, "Change of FVC in dry valleys... ." do the authors mean “the slope of change”?

 

3.8 Section 3.3. I am very confused about this section. What qualitatively or quantitatively results support the contribution of hydropower projects? Although authors wrote a lot of words, but did not give qualitative or quantitative evidence. Indeed, it is not very easy to separate the hydropower effects, however, some analysis still needed.

4.     Discussion and Conclusion need to revise accordingly.

Reviewer 2 Report

The study conducted on Southwest China focused on the effects of precipitation and hydro-projects construction on vegetation cover over the last two decades is properly, however overall analysis and outcomes are not supportive and not qualified for publication.  The structure is not well organized and terms or approaches are not well defined. Tables and Figures need more efforts to be improved and redundant information should be cleared. The most important is the cause-and-effect relationship between hydro-power plants and vegetation cover is blurred to me. Therefore, I will Reject the submission.

 

L21: DVR

What is the abbreviation?

 

L45-47: “However, there are some deficiencies in these studies. Foremost, these studies were usually conducted on a vast region or at a large scale, and reported overall results for the study regions,”

The sentence should be rephrased.

 

L87: Chinaa

China.

 

L129: Table 1.

Also includes annual precipitation that will be consistent to your main text.

 

L132: Figure 1.

Give the labels of latitude and longitude and rivers’ name.

I have no idea what the 14 abbreviations stand for. If they are same main dry valleys in Table 2, there should be 20 instead of 14. You must carefully check them thoroughly.

 

L148: Table 2.

The terms in the climate and name columns have been cut down. Check the same issue of all tables.

 

L168: Figure 3.

Why the construction is separated displayed from other land covers? It seems to me that the construction has a same cover as others. You should show them combined or might mislead their patterns.

 

L181: USGS.

Give hyperlink.

 

L182: 16 days

Provide the name (code) of product.

 

L209-211: For the hydro-power project, please provide the data sources necessary for the analysis.

 

L220-221: three grades of dry valley.

But you did not define what they are and why they should be.

 

L230: Table 4 The long-term average annual FVC of 20 dry valleys.

There are 10 divisions only in the column, and it is really difficult to identify the patterns of low, medium and high grade of FVC from both of Table 4 and Figure 4. You have to improve the presentations of figure according to your definition.

 

L242: 1) the high evaporation (Table 4; Figure 2); 2) anthropological activities.

Anthropogenic activities. Correct the same term thoroughly.

I don’t think you have such supportive information in Table 4 and Figure 2.

 

L247: Yuan River

L250: Anning River

I don’t know where are the locations in maps when you mention.’

 

L293-297: Table 5 and Figure 5 are duplicate and one of them is redundant.

 For Table 5, an asterisk is commonly labeled superscript on numbers instead of using a hook.

For Figure 5, it would be better to give equation including correlation (or R2) and p-value.

 

L299: decadal average FVC.

It is fine to show the difference between first and second decade, but you did not you would adopt this approach.

 

L304-308: “statistically significant decreasing … … while statistically significant increasing” and Figure 6.

Again, I don’t know where are Min and Baishui rivers, and the regions of “statistically significant trends” should be clearly outlined.

Label all rivers’ names.

 

L332-343: “For the Anning River valley, … such as urbanization, and infrastructure, … to severe soil and water loss [47,48,51]. … significant decreasing trends in annual FVC.”

In Results section, you should describe results flatly in lieu of trying to explain. Put the possible reasons to Discussion section.

 

L358: Figure 7.

What the pink color map means?

 

L364-365: “the dynamics of FVC in the Lancang and Jinsha Rivers in DMV, … contributed by the construction of hydro-power plants.”

You only label the time of construction of hydro-power-plants, then tell us that the direct cause-and-effect relationship between them without other analysis. It really confuses me and cannot persuade me.

 

L376-385: “As indicated, … … complex landform and climate in Southwest China.”

Redundant. You need not to repeat the sentence as like Introduction

 

L419-420; “this study, highlighted the importance of hydro-power projects construction on dynamics in vegetation cover”

I cannot find any evidence from the analysis.

Reviewer 3 Report

1.

On line 123 the meaning of DTV is dry-temperate valley, but all over the text it is “temperature” valley.

Please, also check other terms and names for possible inappropriate autocorrection.

 

2.

Figure 2

May be add an insert showing investigating area at the large scale of Asia region, not only China southwest part to better understand valleys loction at global scale?

 

3.

What are GF-1 and GF-2 154 satellites mention at line 154?

 

4.

Table 2 :

 Column “name”. Text is out of the table borders thus is unreadable.

Footnotes numbers are not presented at the table

 

5.

Table 5:

What is the meaning of bold text? If it showing significance than there is no need in column “sig”.

 

6.

In Abstract it is declared “ The results indicated that: 1) the long-term mean annual FVC for the dry valleys, including the dry hot valleys (DHV), dry warm valleys (DWV), and dry temperature valleys (DTV), were much lower than the overall vegetation cover in Southwest China;” but in the article there is no comparison of FVC in valleys with overall vegetation.