Dynamic Change Characteristics of Litter and Nutrient Return in Subtropical Evergreen Broad-Leaved Forest in Different Extreme Weather Disturbance Years in Ailao Mountain, Yunnan Province
Round 1
Reviewer 1 Report (New Reviewer)
The article is based on many years of author's field research. The results obtained by the authors are very valuable and worthy for publication. At the same time, I think that the article should be revised taking into account the comments.
1. I consider the authors' statement that "The forest is the main body of the terrestrial ecosystem" to be incorrect. Each landscape zone has its own predominant types of vegetation.
2. Years with different weather conditions were taken in the study. At the same time, the decomposition of the litter is a continuous process and depends not only on the specific conditions in each specific year, but also on the accumulated prerequisites. It is not clear how this was taken into account in the study. Possibly, the authors differentiated the litter by horizons according to the degree of decomposition. Nothing is said about this in the article.
3. The first author's hypothesis sounds like a known fact. The authors themselves confirm this with references to the literature after the formulation of the hypothesis. The fourth hypothesis as a whole does not look like a hypothesis. It is clear that various factors influence the accumulation and decomposition of the litter, as the authors of the article themselves say. What is the hypothesis in this case?
4. In the description of the study area, it would be better to include a map of it, indicating key areas. The number of key plots is not clear and how homogeneous they were in terms of the plant component.
5. Calendar rather than meteorological seasons were used for analysis. This does not reduce the quality of article, but it levels out the real impact of environmental factors on the accumulation and decomposition of forest litter. Unfortunately, the authors did not take into account the change in the wet and dry seasons in the monsoon climate.
6. From the method, it is not clear how the process of returning nutrients from the litter to the soil was studied. To do this, apparently, it was necessary to differentiate the litter into horizons. How did the authors solve this problem?
7. The first paragraph of the Discussion section refers rather to a review of the literature and has practically nothing in common with a discussion of the results obtained by the authors.
8. The hypotheses put forward by the authors, in my opinion, do not find confirmation due to insufficient time sampling (it is impossible to judge the formation of patterns or some kind of rhythm from one year). In addition, the authors themselves write that the formation of the litter is essentially a random process under the influence of many factors. Putting this statement into the hypothesis, the authors still do not reveal the role of specific factors in the formation of forest litter, but rather declare the same thesis in the Discussion section. In general, the Discussion section requires the author's revision.
9. In my opinion, there is confusion in understanding the terms weather and climate in the article.
Author Response
Response to Reviewer 1 Comments
Title of the Manuscript: Dynamic change characteristics of litter and nutrient return in subtropical evergreen broad-leaved forest in different extreme climate disturbance years in Ailao Mountain, Yunnan Province
Author: Xingyue Liu , Ziyuan Wang, Xi Liu, Zhiyun Lu, Dawen Li and Hede Gong*
Manuscript ID.:forests-1908578
Dear editorial department and review teacher:
Hello! According to your repair suggestions, we have revised the paper, and now we reply to the review comments as follows, hoping to get your correction and adoption.
Point 1: I consider the authors' statement that "The forest is the main body of the terrestrial ecosystem" to be incorrect. Each landscape zone has its own predominant types of vegetation.
Response 1: The review comments were accepted and revised as "Forests are a key component of terrestrial ecosystems", and other revisions have been made in the corresponding parts, please review them in the revised manuscript.
Point 2: Years with different weather conditions were taken in the study. At the same time, the decomposition of the litter is a continuous process and depends not only on the specific conditions in each specific year, but also on the accumulated prerequisites. It is not clear how this was taken into account in the study. Possibly, the authors differentiated the litter by horizons according to the degree of decomposition. Nothing is said about this in the article.
Response 2: Accept the review comments, and make the corresponding reply as follows: This study is a look at the litter situation in 2005-2015, due to the natural extreme ice and snow climate disturbance and extreme drought disturbance are not common, but just waiting in 2005-2015 There are special years in the interval of 5 years, that is, 2005 was not disturbed by extreme weather, 2010 was disturbed by extreme dry climate, and 2015 was disturbed by extreme ice and snow climate, which is more valuable for research. And although litter is a continuous accumulation process, in general, if it is not disturbed by extreme climate, the accumulation is a gradual process, and its change will not be particularly sudden. Interrupted years create opportunities for disturbance. The main purpose is to compare the effects of different extreme climates on the same forest ecosystem and to explore whether extreme climate disturbances will hinder the normal succession process and ecological functions of forest ecosystems. In addition, the litter collected in the article is all fresh litter (meaning that the litter has just fallen and has not yet been decomposed, and the shape of the litter can be roughly seen), and is supplemented and analyzed in the article.
Point 3: The first author's hypothesis sounds like a known fact. The authors themselves confirm this with references to the literature after the formulation of the hypothesis. The fourth hypothesis as a whole does not look like a hypothesis. It is clear that various factors influence the accumulation and decomposition of the litter, as the authors of the article themselves say. What is the hypothesis in this case?
Response 3: The review comments were accepted, and the assumptions were revised accordingly. The specific revisions were as follows: (1) Can extreme drought and ice and snow climate disturbance affect litter yield and nutrient return? (2) Will extreme arid climate disturbance hinder or destroy the normal succession process, seasonal dynamic changes and decomposition rate of forest ecosystems? (3) If there is an impact, is the impact of different extreme climate disturbances on the components of litter consistent?
Point 4: In the description of the study area, it would be better to include a map of it, indicating key areas. The number of key plots is not clear and how homogeneous they were in terms of the plant component.
Response 4: Review comments were accepted and a map was added to the description of the study area to identify the focus areas.
Point 5: Calendar rather than meteorological seasons were used for analysis. This does not reduce the quality of article, but it levels out the real impact of environmental factors on the accumulation and decomposition of forest litter. Unfortunately, the authors did not take into account the change in the wet and dry seasons in the monsoon climate.
Response 5: Accepted review comments and added analysis of wet and dry seasons.
Point 6: From the method, it is not clear how the process of returning nutrients from the litter to the soil was studied. To do this, apparently, it was necessary to differentiate the litter into horizons. How did the authors solve this problem?
Response 6: Accept the review comments and make corresponding responses as follows: First of all, this paper is mainly to explore whether different extreme climate disturbances have an impact on the nutrient return of litter and the extent of the impact, but according to the review comments, the stratification and stratification of litter are still discussed in this paper. Nutrient returns have been modified and supplemented accordingly.
Point 7: The first paragraph of the Discussion section refers rather to a review of the literature and has practically nothing in common with a discussion of the results obtained by the authors.
Response 7: The review comments were accepted and the Discussion section was revised accordingly.
Point 8: The hypotheses put forward by the authors, in my opinion, do not find confirmation due to insufficient time sampling (it is impossible to judge the formation of patterns or some kind of rhythm from one year). In addition, the authors themselves write that the formation of the litter is essentially a random process under the influence of many factors. Putting this statement into the hypothesis, the authors still do not reveal the role of specific factors in the formation of forest litter, but rather declare the same thesis in the Discussion section. In general, the Discussion section requires the author's revision.
Response 8: The review comments were accepted and the assumptions and discussions were revised accordingly.
Point 9: In my opinion, there is confusion in understanding the terms weather and climate in the article.
Response 9: Accept review comments and use the term climate consistently throughout the paper.
Author Response File: 
Author Response.doc
Reviewer 2 Report (New Reviewer)
The content of the paper is not complete, especially the method was not well described, for example they did five years interval but missing 2020 data. Therefore, it cannot be accepted in the present form.
However, here are some suggestions for the authors.
1. Provide map of study sites
2. Clearly explain in method to analyze five years interval study
3. Litterfall is based on forest composition and add forest structure comprehensively, so readers understand the leaves, branches, fruits, flowers from specific species or combined species
4. Statistical notation in Table 2 and 4 is not clear
5. Discussion is weak, please compare to other studies
6. Conclusion is similar to results, repetitions.
Author Response
Response to Reviewer 2 Comments
Title of the Manuscript: Dynamic change characteristics of litter and nutrient return in subtropical evergreen broad-leaved forest in different extreme climate disturbance years in Ailao Mountain, Yunnan Province
Author: Xingyue Liu , Ziyuan Wang, Xi Liu, Zhiyun Lu, Dawen Li and Hede Gong*
Manuscript ID.:forests-1908578
Dear editorial department and review teacher:
Hello! According to your repair suggestions, we have revised the paper, and now we reply to the review comments as follows, hoping to get your correction and adoption.
Point 1: Provide map of study sites
Response 1: Review comments were accepted and a map was added to the description of the study area to identify the focus areas.
Point 2: Clearly explain in method to analyze five years interval study
Response 2: Accept the review comments, and make the corresponding reply as follows: This study is a look at the litter situation in 2005-2015, due to the natural extreme ice and snow climate disturbance and extreme drought disturbance are not common, but just waiting in 2005-2015 There are special years in the interval of 5 years, that is, 2005 was not disturbed by extreme weather, 2010 was disturbed by extreme dry climate, and 2015 was disturbed by extreme ice and snow climate, which is more valuable for research. And although litter is a continuous accumulation process, in general, if it is not disturbed by extreme climate, the accumulation is a gradual process, and its change will not be particularly sudden. Interrupted years create opportunities for disturbance. The main purpose is to compare the effects of different extreme climates on the same forest ecosystem and to explore whether extreme climate disturbances will hinder the normal succession process and ecological functions of forest ecosystems. In addition, the litter collected in the article is all fresh litter (meaning that the litter has just fallen and has not yet been decomposed, and the shape of the litter can be roughly seen), and is supplemented and analyzed in the article. At the same time, 2020 in this region is also a year that is not disturbed by extreme climate, and the data of this year has not been put into use yet, but we have selected 2005 as a normal year, which can be compared with other years affected by different extremes. Years of climate disturbance were compared.
Point 3: Litterfall is based on forest composition and add forest structure comprehensively, so readers understand the leaves, branches, fruits, flowers from specific species or combined species
Response 3: Accepted the review comments and made corresponding additions to the forest structure and composition in the revised manuscript.
Point 4: Statistical notation in Table 2 and 4 is not clear
Response 4: Accept the review comments, and indicate the statistical symbols of Table 2 and Table 4 at the header.
Point 5: Discussion is weak, please compare to other studies
Response 5: Accepted review comments and supplemented the Discussion section with added comparisons with others' research.
Point 6: Conclusion is similar to results, repetitions.
Response 6: Accepted the review comments, and cut and refined the conclusion part.
Author Response File: Author Response.doc
Reviewer 3 Report (New Reviewer)
The work presented by the authors presents relevant information of global interest, however, several sections of the document must be modified or rewritten, precisely, to give it a more global and solid approach.
In the introduction, the comparative approach between what national and foreign academics or students have done should be eliminated; authors should focus on contextualizing what is known about the topic regardless of who has generated that information.
The same think should be solved in the discussion section.
I think that redaction style should be more formal and avoid phrases like “ Generally speaking” (line 393).
Material and methods. Please write sentences in past. It is necessary to define all the terms used, for example what does the category “other litter” comprises?
Conclusions must be rewritten, in the actual state, it are a summary of the results than a really conclusions.
Line 178. Add “above sea level”.
Lines 187-189. Pleas add the species authors.
Lines 191-192. Please resume the sentences to only say that you used the direct collection method to estimate forest litter.
Lines 192-193. What do you mean with “representative evergreen broad leaved forest community”.
Line 191. Pleas add the measure units to “100”.
Line 197. What “certain intervals” means?. Please give a more clear idea of this (distances in meters, for example).
Line 204. What “etc.” means? You must be specific in the wording, please avoid ambiguous ideas or sentences.
Lines 205-206. How did you calculate this?
Lines 208-215. Pleas add fabricant and country for the equipment used.
Lines 223-225. Did you prove the normality and variance homogeneity of data previous of the ANOVA? Please specify.
Figure 1. Please order the graphics by year in ascending order.
Line 266-267. These sentences should be in the material and methods section.
Line 354. Please add the year of publication.
Author Response
Response to Reviewer 3 Comments
Title of the Manuscript: Dynamic change characteristics of litter and nutrient return in subtropical evergreen broad-leaved forest in different extreme climate disturbance years in Ailao Mountain, Yunnan Province
Author: Xingyue Liu , Ziyuan Wang, Xi Liu, Zhiyun Lu, Dawen Li and Hede Gong*
Manuscript ID.:forests-1908578
Dear editorial department and review teacher:
Hello! According to your repair suggestions, we have revised the paper, and now we reply to the review comments as follows, hoping to get your correction and adoption.
Point 1: In the introduction, the comparative approach between what national and foreign academics or students have done should be eliminated; authors should focus on contextualizing what is known about the topic regardless of who has generated that information.
Response 1: Accepted the review comments, cancelled the comparison of the work done by domestic and foreign scholars, and focused on the background knowledge of the theme。
Point 2: The same think should be solved in the discussion section.
Response 2: Accept the review comments, and make corresponding modifications in the discussion section according to the review comments.
Point 3: I think that redaction style should be more formal and avoid phrases like “ Generally speaking” (line 393).
Response 3: Accept the review comments, and modify the whole editing style of the article to make the article more formal.
Point 4: Material and methods. Please write sentences in past. It is necessary to define all the terms used, for example what does the category “other litter” comprises?
Response 4: Accepted the review comments, revised the materials and methods, and supplemented the description of other wastes.
Point 5: Conclusions must be rewritten, in the actual state, it are a summary of the results than a really conclusions.
Response 5: Accept the review comments and modify the conclusions.
Point 6: Line 178. Add “above sea level”；Lines 187-189. Pleas add the species authors；
Lines 191-192. Please resume the sentences to only say that you used the direct collection method to estimate forest litter；Lines 192-193. What do you mean with “representative evergreen broad leaved forest community”；Line 191. Pleas add the measure units to “100”；Line 197. What “certain intervals” means?. Please give a more clear idea of this (distances in meters, for example)；Line 204. What “etc.” means? You must be specific in the wording, please avoid ambiguous ideas or sentences；Lines 205-206. How did you calculate this；Lines 208-215. Pleas add fabricant and country for the equipment used；
Lines 223-225. Did you prove the normality and variance homogeneity of data previous of the ANOVA? Please specify；Figure 1. Please order the graphics by year in ascending order；Line 266-267. These sentences should be in the material and methods section；Line 354. Please add the year of publication.
Response 6: Accepted the review comments, and modified the articles one by one according to each comment proposed by the review. However, due to a large number of changes made to the content of the article, the order of the articles has changed. Please check the specific changes corresponding to each article in the revised version.
Author Response File: Author Response.doc
Round 2
Reviewer 1 Report (New Reviewer)
Dear colleagues!
I have to disagree with the authors that "Forests are a key component of terrestrial ecosystems". This is true only in the zone of distribution of forest landscapes. Once again I would like to emphasize that each landscape zone has its own key types of landscapes.
In the research methods, the authors do not explain the methods for studying the return of nutrients. What do they understand by this, given that the litter itself was not studied, but only fresh litter was studied?
Climate - long-term weather regime in its territory. In the article, when describing specific years, it is correct to talk about weather conditions.
Author Response
Response to Reviewer 1 Comments
Title of the Manuscript: Dynamic change characteristics of litter and nutrient return in subtropical evergreen broad-leaved forest in different extreme weather disturbance years in Ailao Mountain, Yunnan Province
Author: Xingyue Liu , Ziyuan Wang, Xi Liu, Zhiyun Lu, Dawen Li and Hede Gong*
Manuscript ID.:forests-1908578
Dear editorial department and review teacher:
Hello! According to your repair suggestions, we have revised the paper, and now we reply to the review comments as follows, hoping to get your correction and adoption.
Point 1: I have to disagree with the authors that "Forests are a key component of terrestrial ecosystems". This is true only in the zone of distribution of forest landscapes. Once again I would like to emphasize that each landscape zone has its own key types of landscapes.
Response 1: Agreed with the reviewer's opinion that forests are only an important part of the zone of distribution of forest landscapes, and made the following modifications according to the reviewer's opinion: ‘Forests are a key component of terrestrial ecosystems’ was deleted in the text, that is, ‘Forests are a key component of terrestrial ecosystems, and litter is an important carbon pool for forest ecosystems.’ was changed to ‘Forest litter is an important carbon pool for forest ecosystems. ‘
Point 2: In the research methods, the authors do not explain the methods for studying the return of nutrients.
Response 2: Accept the review comments and make the following modifications: nutrient return amount=litter amount×The nutrient content and nutrient return amount of litter are calculated according to the collected litter amount and the measured nutrient content. Previously, the content of this part was written in the data statistics and analysis part, which is not easy to be found by the readers. Therefore, according to the review comments, the research methods of nutrient return amount are separately supplemented in the summary and research methods in the text.
Point 3:What do they understand by this, given that the litter itself was not studied, but only fresh litter was studied?
Response 3: We accepted the review comments and our understanding of the issues raised in the review comments is as follows: This paper mainly aims to analyze whether and how different extreme weather affects forest litter through the research on litter yield, nutrient content and nutrient return under different extreme weather disturbances and compared with normal years without extreme weather disturbances, One of the main research objects is litter yield, which refers to the total amount of all forest litters in the forest area per unit time and area, including annual and monthly litter. However, the direct collection method is often used to measure the forest litter, that is, the Litter trap method is used to estimate the forest litter. According to the analysis of the references referred to and used for reference, the amount of litter in the study is mainly to directly collect all fresh litter from plants. This study focuses on estimating the output of the whole fresh litter layer collected in the collector, Instead of studying the standing amount of litter (that is, the amount of forest litter accumulated on a unit area of forest land, which is the dead organic matter on the soil surface, generally composed of undecomposed, semi decomposed and decomposed litter), this paper only studies the overall level of fresh litter produced by plants in the forest. The characteristics of litter itself include the amount of litter, Therefore, we believe that the research on fresh litter collected in this paper can meet the main research purpose of this paper.
Point 4:Climate - long-term weather regime in its territory. In the article, when describing specific years, it is correct to talk about weather conditions.
Response 4: Accept the review comments, and make the following modifications according to the review comments: climate refers to the weather conditions for a long time, so when describing specific years in the article, the word climate is replaced by the word weather, that is, extreme weather conditions are discussed, and all the specific modifications can be seen in the article.
Author Response File: Author Response.doc
Reviewer 2 Report (New Reviewer)
The authors carefully addressed all the revisions. The manuscript was improved substantially. The paper needs some minor edition to polish the language and avoid grammatical mistakes. Other than that, I believe is ready for going to publication
Author Response
Response to Reviewer 2 Comments
Title of the Manuscript: Dynamic change characteristics of litter and nutrient return in subtropical evergreen broad-leaved forest in different extreme weather disturbance years in Ailao Mountain, Yunnan Province
Author: Xingyue Liu , Ziyuan Wang, Xi Liu, Zhiyun Lu, Dawen Li and Hede Gong*
Manuscript ID.:forests-1908578
Dear editorial department and review teacher:
Hello! According to your repair suggestions, we have revised the paper, and now we reply to the review comments as follows, hoping to get your correction and adoption.
Point 1: The authors carefully addressed all the revisions. The manuscript was improved substantially. The paper needs some minor edition to polish the language and avoid grammatical mistakes. Other than that, I believe is ready for going to publication
Response 1: Thanks very much for the valuable comments and recognition of the reviewers, and revised the language of the full text to improve some grammatical errors in the article.
Author Response File: Author Response.doc
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
please see my comments on the pdf file. English must be checked and significantly improved by a native speaker.
Comments for author File: 
Comments.pdf
Author Response
Response to Reviewer 1 Comments
Title of the Manuscript: Characteristics of dynamic changes in litter and nutrient restitution in the Montane Evergreen, Broad-leaved Forests
Author: Xingyue Liu , Ziyuan Wang, Xi Liu, Zhiyun Lu, Dawen Li and Hede Gong*
Manuscript ID.:forests-1776698
Dear editorial department and review teacher:
Hello! According to your repair suggestions, we have revised the paper, and now we reply to the review comments as follows. And for the language problem of your paper (Extensive editing of English language and style required), I pre edited the English language on the English editing website (https://www.mdpi.com/authors/english) provided by your journal and modified the language of the full text. hoping to get your correction and adoption! Thank you again!
Point 1: :title need to be re-written. Its not clear what meaning it delivers
Response 1: accept expert opinions, and rewrite the title according to expert opinions, so that the title can more clearly express the research content contained.(see the uploaded revised article for all detailed modifications)
The specific modifications are as follows:
Original text:
Characteristics of dynamic changes in litter and nutrient restitution in the Montane Evergreen, Broad-leaved Forests
After modification:
Characteristics of dynamic changes in litter and nutrient restitution in the Montane Moist Evergreen Broad-leaved Forest in different years in Ailao Mountains, Yunnan
Point 2:Abstract is too long
Response 2: Accept the experts' opinions, shorten the contents of the summary according to the experts' opinions, and modify the details pointed out by the experts. (see the uploaded revised article for all detailed modifications).
Original text:
Abstract: (1) Background: Forest litter is a very important index for forest ecosystem biomass, nutrient cycling and energy flow. Evergreen, broad-leaved forest is an important vegetation type in high altitude areas of western China. Therefore, studying dynamic changes in the amount of litter, composition, nutrient content and return in these forests can provide a theoretical reference for nutrient cycling and long-term sustainable development. (2) Methods: Square litter collectors were randomly set up to collect litter monthly. After drying to a constant mass, we calculated seasonal and annual litter volume and the content of organic carbon (C), total nitrogen (N), total phosphorus (P), total potassium (k), total sulfur (S), total calcium (Ca) and total magnesium (Mg). We tracked dynamic changes in litter quantity, nutrient composition and nutrient components in different years. (3) Results: The litter amount from 2005 to 2015 was 7704.15-8817.50 kg·hm-2; The composition mainly included branches, leaves, fruit (flowers) and other components (bark, moss, lichen, etc.), of which the proportion of leaves was the largest, accounting for 41.70%-61.52%. The monthly changes and total amount in different years showed a single or double peak change law, and the monthly litter of different components in different years had significant seasonality. In this study,
nutrient content was higher than that of litter branches in each year. The total amount of litter and different nutrient concentrations of each component were similar (C > Ca > N> K > Mg > S > P). The nutrient return amount in different years was 2005 > 2015 > 2010. The nutrient return amount of litter leaves is greater than that of litter branches. The annual nutrient return amount is roughly proportional to the litter amount. The nutrient return amount of litter in this forest ecosystem was higher than that of other evergreen, broad-leaved forests in the subtropical zone. (4) Conclusion: The annual litter and nutrient return of the evergreen broad-leaved forest in the study area were higher than those in other subtropical areas, and both were the highest in 2005; The seasonal dynamic change characteristics of nutrient content of each component of litter in different years are quite different, but consistent with the sequence of nutrient return, the overall performance is C>Ca>N>K>Mg>S>P, and the litter leaves are higher than the litter branches.
After modification:
Abstract: Litter is an important medium connecting plants and soil nutrients in terrestrial ecosystems, which is helpful for understanding the mechanism of material circulation in terrestrial ecosystems. By studying the dynamic change characteristics of litter production, nutrient content, and return of evergreen broad-leaved forest in Ailao Mountain, which can provide a theoretical reference for managing the nutrient balance of subtropical evergreen broad-leaved forest land, improving the carbon sink function of forest ecosystems and their sustainable development. Square litter collectors were randomly set up to collect litter. After drying to a constant mass, we calculated the seasonal and annual litter volume and the contents of organic carbon (C), total nitrogen (N), total phosphorus (P), total potassium (k), total sulfur (S), total calcium (Ca), and total magnesium (Mg). We tracked dynamic changes in litter quantity, nutrient composition, and nutrient components across different years. The results showed that the amount of litter from 2005 to 2015 was 7704-8818 kg·hm-2; the composition mainly included branches, leaves, fruit (flowers), and other components (bark, moss, lichen, etc.), of which the proportion of leaves was the largest, accounting for 41.70%-61.52%. The monthly
changes and total amounts in different years exhibited single or double peak changes, and the monthly litter components in different years showed significant seasonality. In this study, the nutrient content of litter was higher than that of litter branches in each year. The total amount of litter and the nutrient concentration of each component are C, Ca, N, K, Mg, S, P from large to small. The annual return amount of nutrients in different years was the largest in 2005 (3799kg·hm-2) and the smallest in 2010 (2658kg·hm-2). The returns of nutrients in litter leaves were greater than that of litter branches. The ratio of nutrient returns of litter and litter branches from 2005 to 2010 were 2.03, 1.23 and 3.69 respectively. The research shows that the annual litter and nutrient returns of the evergreen broad-leaved forest in the study area were higher than those in other subtropical areas. The annual amount of litter and nutrient returns fluctuate greatly between years. The seasonal dynamic variation characteristics of nutrient contents of each component of litter are quite different, houwever consistent with the sequence of nutrient return.
The above part is about the complete modification of the summary part, and the following questions are to modify the specific issues of the summary raised by the review item by item：
Point 3:delete Bacground
Response 3:accept the expert opinion and delete the background according to the expert opinion. (see the uploaded revised article for all detailed modifications).
Point 4:this doesnt make any sense. Please selete this sentence
Response 4:accept the expert opinion and delete this sentence according to the expert opinion.(see the uploaded revised article for all detailed modifications)
The specific modifications are as follows:
Original text:
Forest litter is a very important index for forest ecosystem biomass, nu- 6 trient cycling and energy flow.
After modification:
This sentence has been deleted, and it is no longer in the text.
Point 5:this doesnt mesn anything here. It is important thats why you studied. but why is it important?
Response 5:accepted the expert opinion, deleted this sentence, and added a sentence about the importance and necessity of conducting this research.(see the uploaded revised article for all detailed modifications)
The specific modifications are as follows:
Original text:
Evergreen, broad-leaved forest is an important vegetation type in high altitude areas of western China.
After modification:
Litter is an important medium connecting plants and soil nutrients in terrestrial ecosystems, which is helpful to understand the mechanism of material circulation in terrestrial ecosystems.
Point 6:delete Methords
Response 6:accept expert opinions. According to the opinions of experts, the word was deleted, the content of the summary was reduced, and the format of the summary was improved.(see the uploaded revised article for all detailed modifications)
Point 7:why monthly?
Response 7:accept expert opinions. Monthly is deleted according to the opinions put forward by experts. The monthly observation refers to the test frequency of relevant research and determines the test frequency of the experiment according to the actual situation. Only by conducting the experiment every month can we observe the inter monthly dynamics of litter every year and the change trend and peak value of litter in different months, and then we can observe the seasonal dynamic change law of litter.(see the uploaded revised article for all detailed modifications)
Point 8:what does dynamic changes mean here?
Response 8:dynamic changes refers to the total production, nutrient element content, nutrient return and other indicators of each component and total amount of litter. They are not static but dynamic between different years, seasons and different months of the same year. Dynamic changes also refers to their dynamic change law.(see the uploaded revised article for all detailed modifications)
Point 9:delete Results
Response 9:accept expert opinions. According to the opinions of experts, the word was deleted, the content of the summary was reduced, and the format of the summary was improved.(see the uploaded revised article for all detailed modifications)
Point 10:no need this part( 7704.15-8817.50)
Response 10: accept expert opinions. According to the opinions of experts, the word was deleted, the content of the summary was reduced, and the format of the summary was improved. However, referring to the template format required by your journal, I don't know whether all the numbers in the article need to be kept in integers, so only the decimal digits of some numbers pointed out by you in the review will be modified. If you need to modify the numbers of the full text, please give me another chance to modify them.(see the uploaded revised article for all detailed modifications)
Point 11:which nutrient
Response 11: accept expert opinions. The nutrient content of litter is higher than that of litter branches, which has been supplemented and improved.(see the uploaded revised article for all detailed modifications)
Original text:
In this study, nutrient content was higher than that of litter branches in each year.
After modification:
In this study, the nutrient content of litter was higher than that of litter branches in each year.
Point 12:there should be a better way of writing(C > Ca > N> K > Mg > S > P).
Response 12: accept expert opinions. This expression has been modified.(see the uploaded revised article for all detailed modifications)
Original text:
The total amount of litter and different nutrient concentrations of each component were similar (C > Ca > N> K > Mg > S > P).
After modification:
The total amount of litter and the nutrient concentration of each component are C, Ca, N, K, Mg, S, P from large to small.
Point 13:same here(2005>2015>2010)
Response 13: accept expert opinions. The expression of this content has been modified according to expert opinions.(see the uploaded revised article for all detailed modifications)
Original text:
The nutrient return amount in different years was 2005 > 2015 > 2010.
After modification:
The annual return amount of nutrients in different years was the largest in 2005 (3799kg·hm-2) and the smallest in 2010 (2658kg·hm-2).
Point 14:need numbers for results
Response 14: accept expert opinions. According to the opinions put forward by experts, the data of this part is supplemented and the corresponding text content is modified.(see the uploaded revised article for all detailed modifications)
Original text:
The nutrient return amount of litter leaves is greater than that of litter branches. The annual nutrient return amount is roughly proportional to the litter amount. The nutrient return amount of litter in this forest ecosystem was higher than that of other evergreen, broad-leaved forests in the subtropical zone.
After modification:
The return amount of nutrients in litter leaves was greater than that of litter branches. The ratio of nutrient return amount of litter and litter branches from 2005 to 2010 was 2.03, 1.23 and 3.69 respectively.
Point 15:delete Conclusion
Response 15: accept expert opinions. According to the opinions of experts, the word was deleted, the content of the summary was reduced, and the format of the summary was improved.(see the uploaded revised article for all detailed modifications)
Point 16:unnecessaily too long sentences
Response 16: accept expert opinions. According to the opinions put forward by experts, the unimportant sentences in the conclusion part are deleted, and only the key conclusion of the article is retained.(see the uploaded revised article for all detailed modifications)
Original text:
The annual litter and nutrient return of the evergreen broad-leaved forest in the study area were higher than those in other subtropical areas, and both were the highest in 2005; The seasonal dynamic change characteristics of nutrient content of each omponent of litter in different years are quite different, but consistent with the sequence of nutrient return, the overall performance is C>Ca>N>K>Mg>S>P, and the litter leaves are higher than the litter branches.
After modification:
The research shows that the annual litter volume and nutrient return amount of evergreen broad-leaved forest in the study area are higher than that of evergreen broad-leaved forest in other subtropical regions. The annual litter amount and nutrient return volume fluctuate greatly between years. The seasonal dynamic variation characteristics of nutrient content of each component of litter are quite different, but they are consistent with the sequence of nutrient return amount.
Point 17:too long for keyword
Response 17: accept expert opinions. According to the opinions of experts, too long keywords have been reduced.(see the uploaded revised article for all detailed modifications)
Original text:
Keywords: litter quantity; Nutrient content; Return of nutrients; the montane moist evergreen broad-leaved forest in Ailao Mountains
After modification:
Keywords: litter quantity; Nutrient content; Return of nutrients; montane moist evergreen broad-leaved forest
Point 18:Instroduction is too short
Response18: accept expert opinions. According to the opinions put forward by experts, the details of the introduction are specifically modified, and the contents of the introduction such as the research objectives and assumptions of the article are added.(see the uploaded revised article for all detailed modifications)
Original text:
- Introduction
Forest litter is an important part of forest ecosystem function [1-3]. Forest litter production and nutrient return directly affect forest primary productivity. Therefore, forest litter production and nutrient return is very important to understanding nutrient availability and productivity in forest ecosystem[4-9]. China's subtropical forest is a rare vegetation type. At present, the montane moist evergreen broad-leaved forest in the Ailao Mountains Nature Reserve in Yunnan Province is the largest subtropical evergreen broad-leaved forest in China. This reserve is of great significance for studying the dynamics of litter yield, nutrient cycling and composition characteristics in broad-leaved forests[10-12].
Litter has traditionally been an important part of research in forest ecology, biogeochemistry and forest soil science[13-17]. In 1964, Barry et al.[18-19] analyzed global forest litter and estimated the annual litter of several forest types in various climate zones around the world. They found that forest litter has obvious seasonal dynamics. Descheemaeker et al.[18-19] studied seasonal dynamics of litter and found that water availability was the dominant factor. Research on dynamic changes in forest litter in China has made great progress since the late 1960s and 1980s [14,21].
In recent decades, there have been many studies on litter in[1,3,22-24], but most are single research results of litter yield, nutrient elements or nutrient return for one or several years. And, research on evergreen broad-leaved forests in this area mainly focuses on vegetation type and diversity. There are relatively few comparative and comprehensive studies on litter yield and nutrient return[5,8,25-28]. Therefore, we measured the amount of litter, nutrient element content and return amount of each component in the Ailao Mountains National Nature Reserve in different years to explore interannual, monthly and seasonal dynamics. Summarizing the dynamics and nutrient cycling in different years provides theoretical basis for the development, utilization and protection of the Ailao Mountains National Nature Reserve.
After modification:
Forest litter production and nutrient return are the most direct reflections of the function of the forest ecosystem and the level of primary productivity. Their dynamic changes are often used to explain the basic nutrient inputs into soil systems, and play an important role in maintaining soil fertility and promoting normal material circulation and energy flow of the ecosystem [1-3]. Therefore, forest litter production and nutrient return are very important to better understanding nutrient availability and productivity in forest ecosystems[4-9]. China's subtropical forest is a significant and special vegetation type. The montane moist evergreen broad-leaved forest in the Ailao Mountains Nature Reserve in Yunnan Province is the largest subtropical evergreen broad-leaved forest in China. This reserve is of great significance for studying the dynamics of litter yield, nutrient cycling, and composition characteristics in broad-leaved forests[10-12].
Litter has traditionally been an important focus of research in forest ecology, biogeochemistry, and forest soil science[13-17]. In 1964, Barry et al.[18-19] analyzed global forest litter and estimated the annual litter of several forest types in various climate zones around the world. They found that forest litter exhibits clear seasonal dynamics. Descheemaeker et al.[18-19] studied the seasonal dynamics of litter and found that water availability was the dominant factor. Research on dynamic changes in forest litter in China has shown considerable progress since the late 1960s [14,21].
In recent decades, there have been many studies on litter[1,3,22-24]; howere most are single research results of litter yield, nutrient elements, or nutrient return for one or several years. additionally, research on evergreen broad-leaved forests in this area has mainly focusesd on the vegetation type and diversity. There have been relatively few comparative and comprehensive studies on the litter yield and nutrient return[5,8,25]. A large number of studies on litter dynamics have been carried out around the world, and it is found that the yield and dynamics of litter not only depend on the biological and ecological characteristics of forest constituent tree species, but also depend on factors such as geographical environment and climatic conditions[26-28]. Therefore, although a lot of research has been carried out on litter dynamics and nutrient element return at home and abroad, with the changes of geographical location, climatic factors and tree species composition, there are also differences in litter volume and substrate quality. The unique geographical location of the study area has important ecological value. The research on litter dynamics in this area is conducive to a comprehensive understanding of the structure and function of subtropical evergreen broad-leaved forest ecosystem.
The main objective of the present study is to determine the amount of litter in different parts of the primeval forest in Ailaoshan National Nature Reserve across different years and the nutrient element content and return amount of each component, so as to explore the interannual change, monthly dynamic change, seasonal dynamic change characteristics of each component of litter, the total amount of litter, and the significance of the differences between each component and the nutrient element content and return amount, Summarize the change law of litter and nutrient circulation law in different years, and enrich the research on the ecological structure and function of the Montane Moist Evergreen Broad-leaved Forest. Our specific working hypothesis are: 1. The changes of litter components, total litter amount, nutrient element content and return amount between years have an obvious increasing or decreasing trend, that is, the above indicators increase or decrease with the increase of years; 2. The components of litter and total litter show obvious characteristics of monthly and seasonal dynamic changes. For example, the trend of monthly dynamic changes is obvious single peak or double peak mode, and the peak of litter is concentrated in a month or a season; 3. There are significant differences between the components and total amount of litter and the content of nutrient elements and return amount. These knowledge can provide basic data for studying the material cycle and nutrient balance of subtropical evergreen broad-leaved forest ecosystem, and also provide a theoretical basis for the development, utilization, and protection of Ailao Mountain National Nature Reserve.
The above part is about the complete modification of the introduction, and the following questions are to modify the specific questions of the introduction raised by the review item by item：
Point 19:of course but this information here is no need
Response 19: accept expert opinions. According to the opinions put forward by experts, this sentence has been deleted.(see the uploaded revised article for all detailed modifications)
Point 20:that is what being produced in forest isnt it? What does rare vegetation type mean here?
Response 20: accept expert opinions. According to the opinions of experts, this sentence has been revised to improve the content of the article.In addition, rare stands for a very important and special meaning here, and the word has been modified and replaced.(see the uploaded revised article for all detailed modifications)
Original text:
Forest litter is an important part of forest ecosystem function[1-3]. Forest litter production and nutrient return directly affect forest primary productivity. Therefore, forest litterproduction and nutrient return is very important to understanding nutrient availability and productivity in forest ecosystem[4-9]. China's subtropical forest is a rare vegetation type.
After modification:
Forest litter production and nutrient return are the most direct reflection of the function of forest ecosystem and the level of primary productivity. Their dynamic changes are often used to explain the basic nutrient input into the soil system, and play an important role in maintaining soil fertility and promoting the normal material circulation and energy flow of the ecosystem[1-3]. Therefore, forest litter production and nutrient return is very important to better understanding nutrient availability and productivity in forest ecosystem[4-9]. China's subtropical forest is a significant and special vegetation type.
Point 21:the introduction need to include what is known, what is unknown, what this study promise and what is the objectives? None is clear here
Response 21: accept expert opinions. According to the opinions put forward by experts, the content of the introduction is expanded in detail, the description of the relevant content that has been studied and the relevant content that has not been studied is modified, and the objectives and assumptions of this study are added, so as to express the content of the article more clearly.(see the uploaded revised article for all detailed modifications)
Point 22:any classification for soil type?
Response 22: accept expert opinions. And the specific conditions of the soil have been supplemented and improved in detail.(see the uploaded revised article for all detailed modifications)
Original text:
The soil is fertile, acidic yellow-brown soil.
After modification:
The soil is fertile, acidic mountain yellow-brown soil[11,13], and the soil humus is brownish black, and the mineral soil layer is loose, mainly in granular structure. The surface soil layer has good water permeability and strong water conservation ability.
Point 23:for this kind of natural ecosystems plotting or experimental design can not be used.
Response 23: accept expert opinions, the data of this study are obtained through field experiments. According to my actual experimental design, I have also referred to many experimental design schemes involved in other relevant research contents to improve and supplement the writing of the experimental scheme in detail in order to explain how to establish a clear sample. Please review the revised content again. If there are any problems, we must revise it again in detail. Thank you very much!(see the uploaded revised article for all detailed modifications)
Original text:
Representative evergreen broad-leaved forest communities in the region were selected; a square fixed sample plot with a sample area of 1hm2(100m×100m) was established; and the established fixed sample plot was divided into 100 10m×10m small sample squares—25 of which were randomly selected for long-term observation
After modification:
Direct collection method is often used to measure forest litter, that is, the litter collector method is used to estimate forest litter. Select the representative evergreen broad-leaved forest community in this area, and set up 1hm2 (100m×100m) of the standard sample plot, and the fixed sample plot is a square with a horizontal projection of 100m*100m. The established fixed sample plot was divided into 100 10m×10m small sample squares, five collectors are randomly placed and installed along the uphill, middle and downhill slopes at certain intervals in the fixed sample plot, and a total of 25 collectors in the sample plot are used as duplicates for long-term observation
Point 24:then how the effect is defferent? How do plots being set up? Why 1hm2?
Response 24: accept expert opinions, according to their actual experimental design, refer to the experimental design scheme of many relevant literatures, and improve and supplement the writing of the experimental scheme in detail to solve and explain how the sample plot is established. The purpose of establishing 1 hectare sample plot and setting 25 collectors randomly at a certain distance is: (1) 1hm2 square sample plot is more conducive to experimental observation and division of small foreign lands; (2) Try to set up a sample plot with a wide area (1hm2) to test the scope of the study area more conveniently and comprehensively; (3) Five collectors are set on the uphill slope, the middle slope and the downhill slope, with a total of 25 collectors as repetitions to ensure the accuracy, comprehensiveness and representativeness of the data.(see the uploaded revised article for all detailed modifications)
Original text:
Representative evergreen broad-leaved forest communities in the region were selected; a square fixed sample plot with a sample area of 1hm2(100m×100m) was established; and the established fixed sample plot was divided into 100 10m×10m small sample squares—25 of which were randomly selected for long-term observation
After modification:
Direct collection method is often used to measure forest litter, that is, the litter collector method is used to estimate forest litter. Select the representative evergreen broad-leaved forest community in this area, and set up 1hm2 (100m×100m) of the standard sample plot, and the fixed sample plot is a square with a horizontal projection of 100m*100m. The established fixed sample plot was divided into 100 10m×10m small sample squares, five collectors are randomly placed and installed along the uphill, middle and downhill slopes at certain intervals in the fixed sample plot, and a total of 25 collectors in the sample plot are used as duplicates for long-term observation
Author Response File: Author Response.docx
Reviewer 2 Report
Title of the Manuscript: Characteristics of dynamic changes in litter and nutrient restitution in the Montane Evergreen, Broad-leaved Forests
Manuscript ID forests-1776698
Dear Sir/Madam,
Thanks for giving me an opportunity to review the manuscript. Now I read manuscript thoroughly and submitting my comments on the manuscript for your kind consideration. The details of the comments are as follows:
Comments
Abstract
· If possible, the abstract, should be short only providing important information.
· Key words are too long, pl short it
Introduction
· The introduction section is short and can be updated with the recent citations.
· The hypothesis and clear objectives of the study to be given.
Materials and Method
· This section can also be improved using more detailed information’s of the methods.
· Use proper subscript and superscript i.e., H2O2-H2SO4 (line 89)
Results
· Table-1 In this Table you are repeating litter ever time. Better give one line of litter and in second line use branch, leaf, fruit other and total for clear understanding.
· Similarly, you can repeat for Table-2, Table-4
· In figure 1 a, b, c the parameter on X axis and Y axis, the legend is not uniform. Please improve figures.
· Figure-2 a, b, c, d etc. all values given in y axis without unit.
Discussion
· The section is almost ok but can be strengthen.
Conclusion
· The section is very long, please short it giving only some important clear findings of the present study.
Over all I found that authors have made good effort in the manuscript. However, suggested comments are essentially required for the quality of manuscript.
Author Response
Response to Reviewer 2 Comments
Title of the Manuscript: Characteristics of dynamic changes in litter and nutrient restitution in the Montane Evergreen, Broad-leaved Forests
Author: Xingyue Liu , Ziyuan Wang, Xi Liu, Zhiyun Lu, Dawen Li and Hede Gong*
Manuscript ID.:forests-1776698
Dear editorial department and review teacher:
Hello! According to your repair suggestions, we have revised the paper, and now we reply to the review comments as follows, hoping to get your correction and adoption.
Point 1:Abstract: If possible, the abstract, should be short only providing important information. Key words are too long, pl short it
Response 1:
accept the expert's opinions, and simplify and condense the abstract and keywords according to the expert's opinions. Please review the revised content again, and look forward to your comments.(see the uploaded revised article for all detailed modifications)
Point 2:Introduction:The introduction section is short and can be updated with the recent citations. The hypothesis and clear objectives of the study to be given
Response 2:
accept expert opinions, and add relevant introduction contents such as research objectives and assumptions of the article according to expert opinions, in order to further expand and improve the introduction contents. Please review the revised content again, and look forward to your comments.(see the uploaded revised article for all detailed modifications).
Point 3:Materials and Method:This section can also be improved using more detailed information’s of the methods. Use proper subscript and superscript i.e., H2O2-H2SO4 (line 89)
Response 3:
accept expert opinions, and improve and describe the method in more detail according to expert opinions, in order to further expand and improve the content of the method. In addition, the superscript and subscript questions you raised have also been revised.(see the uploaded revised article for all detailed modifications).
Point 4:Results:Table-1 In this Table you are repeating litter ever time. Better give one line of litter and in second line use branch, leaf, fruit other and total for clear understanding. Similarly, you can repeat for Table-2, Table-4. In figure 1 a, b, c the parameter on X axis and Y axis, the legend is not uniform. Please improve figures. Figure-2 a, b, c, d etc. all values given in y axis without unit.
Response 4:
accept the expert opinions, and supplement and improve the corresponding forms according to the expert opinions.(see the uploaded revised article for all detailed modifications)
Point 5:Discussion:The section is almost ok but can be strengthen.
Response 5:
accept the expert opinions, and appropriately supplement and strengthen the discussion part according to the expert opinions.(see the uploaded revised article for all detailed modifications)
Point 6:Conclusion:The section is very long, please short it giving only some important clear findings of the present study.
Response 6:
accept expert opinions, shorten the conclusion according to expert opinions, and only list the key conclusions in this study.(see the uploaded revised article for all detailed modifications)
Author Response File: Author Response.docx
Reviewer 3 Report
Reviewer
MDPI - forests
Manuscript Number: forests-1776698
Title: «Characteristics of dynamic changes in litter and nutrient restitution in the Montane Evergreen, Broad-leaved Forests».
The objectives of this paper where forest litter is a very important index for forest ecosystem biomass, nutrient cycling, and energy flow. Significantly, the annual return of litter and nutrients in the evergreen broadleaf forest in the study area was 26 times higher than in other subtropical areas. This study is very important in assessing the potential of the forest and its performance of ecological functions within the forest ecosystem.
line 59 What is the purpose and objectives of the study?
line 161 Add labels to the axes of figure 2.
Author Response
Response to Reviewer 3 Comments
Title of the Manuscript: Characteristics of dynamic changes in litter and nutrient restitution in the Montane Evergreen, Broad-leaved Forests
Author: Xingyue Liu , Ziyuan Wang, Xi Liu, Zhiyun Lu, Dawen Li and Hede Gong*
Manuscript ID.:forests-1776698
Dear editorial department and review teacher:
Hello! According to your repair suggestions, we have revised the paper, and now we reply to the review comments as follows, hoping to get your correction and adoption.
Point 1:line 59 What is the purpose and objectives of the study?
Response 1:
accept expert opinions, and add relevant introduction contents such as research objectives and assumptions of the article according to expert opinions, in order to further expand and improve the introduction contents. Please review the revised content again, and look forward to your comments.(see the uploaded revised article for all detailed modifications).
Point 2:line 161 Add labels to the axes of figure 2
Response 2:
accept expert opinions, add shaft labels according to expert opinions, and improve the table.(see the uploaded revised article for all detailed modifications).
Author Response File: Author Response.docx
