The Influence of Climate Change on Three Dominant Alpine Species under Different Scenarios on the Qinghai–Tibetan Plateau
Round 1
Reviewer 1 Report
This study explores the influence of climate change on two dominant alpine trees (Picea crassifolia Kom and Sabina przewalskii Kom) and one dominant alpine shrub (Potentilla Parvifolia Fisch) under different climate scenarios on the QTP. There were significant differences in the potential distribution of two dominant alpine trees and one dominant alpine shrub under four climate scenarios in the 2050s and 2070s, including expansion, change, and contraction. This study provides an important reference for the conservation of P. crassifolia, S przewalskii, P. Parvifolia in the QTP under climate change.
The article is generally well written and presents important results to be published. The manuscript is clear, relevant to the field, and presented in a well-structured manner, while the cited references are up-to-date. By not presenting a hypothesis (and it would be interesting to include it) it is impossible to prove it. In this work, the methodology and results are clearly presented; therefore they are reproducible based on the details provided.
I suggest that in the introduction of the work they include hypotheses or predictions according to the experience of other previous works or with the habitat descriptions of the 3 species, these will respond to future climate change scenarios. In this way, by incorporating predictions or hypotheses, these can be contrasted in the discussion.
Regarding the study area, it is not clear to me that Figure 1 corresponds to the Chinese part of the Tibetan Plateau, not including Tibet belonging to other countries. Also, the term Qinghai corresponds to a province of China. My suggestion is that either a map of Tibet be included and located there the points of occurrence of the species, or that they better define the study area (whether or not it is the province or what is the study extension).
For instance:
Line 193 Figure 3. The current potential geographical distribution of P crassifolia, S przewalskii, and P parvifolia.
1) it is not known to which species each figure corresponds
2) it is not understood that it indicates the gray color
3) it is not known what the dark gray lines are
4) The three trees or shrubs have similar heights, although P parvifolia is clearly a shrub.
5) It is not known whether or not it is in QTP
6) latitude and longitude cannot be read by letter size
Regarding the use of the aspect, it is measured in degrees and present values between 0 and 360 °, the North exposure varies between 315 and 45º (including 0), while the South exposure between 135 and 215 °. If the values per exposure are averaged, the averages will present similar values at 180º in both exposures. To avoid these errors (And the error that an aspect of 1 ° is totally opposite to 359 °, but at the same time, it is very similar), its important to convert the aspect in degrees by the sine and cosine function into two variables: north-south (ExN) and east-west (ExE). Sine values range from -1 (west) to 1 (east), while cosine values range from -1 (south) to 1 (north).
See:
Stupariu, M. S.; Pàtru-Stupariu, I. G.; Cuculici, R. Geometric Approaches to Computing 3D-Landscape Metrics. LO 2010, 24, 1-12.
Jenness, J.S. 2004. Calculating landscape surface area from digital elevation models. Wildlife Society Bulletin 32, 829-839.
Also, I include minor format modifications in the attached file.
Line 9: Chengdu610041 change to Chengdu 610041.
Line 37: ),. change to ).
Line 40: Qinghai–Tibetan Plateau change to Qinghai-Tibetan Plateau
Line 104: the legend of the Figure does not express the content.
Line 203: , change to and
Comments for author File: 
Comments.pdf
Author Response
Dear Reviewer:
On behalf of my co-authors, thank you very much for your email with the reviewers’ comments regarding our manuscript. We are highly appreciating the reviewers’ positive and constructive comments and suggestions on our manuscript entitled “The influence of climate change on three dominant alpine species under different scenarios on the Qinghai-Tibetan Plateau” (diversity-1512651). We have carefully revised the manuscript and now submit the new version according to the reviewers’ comments. Our incorporation of the comments is explained point-by-point as follows:
[1] I suggest that in the introduction of the work they include hypotheses or predictions according to the experience of other previous works or with the habitat descriptions of the 3 species, these will respond to future climate change scenarios. In this way, by incorporating predictions or hypotheses, these can be contrasted in the discussion.
Answer: We have added the habitat descriptions of the three species in the introduction as follows:
Picea crassifolia habitats on the shady slopes, semi shady slopes and humid valleys in the mountains with an altitude of 1750-3100 m (a.s.l), and it is endemic to China, dis-tributed in Qilian Mountains, Qinghai, Gansu, Ningxia, Inner Mongolia. Sabina prze-walskii grows on the sunny slope of 2600-4000 m (a.s.l), and it is endemic to China, dis-tributed in Qinghai, Gansu Hexi Corridor, and the north of Sichuan. Potentilla parvifolia favorites dry hillside, rock crack, forest edge and forest with altitude of 900-5000 m (a.s.l), and it is distributed in Heilongjiang, Inner Mongolia, Gansu, Qinghai, Sichuan and Tibet in China. (Lines:50-56)
[2] Regarding the study area, it is not clear to me that Figure 1 corresponds to the Chinese part of the Tibetan Plateau, not including Tibet belonging to other countries. Also, the term Qinghai corresponds to a province of China. My suggestion is that either a map of Tibet be included and located there the points of occurrence of the species, or that they better define the study area (whether or not it is the province or what is the study extension).
Answer: We have modified Figure 1 .
(Line:108)
[3] Line 193 Figure 3. The current potential geographical distribution of P crassifolia, S przewalskii, and P parvifolia.
1) it is not known to which species each figure corresponds
2) it is not understood that it indicates the gray color
3) it is not known what the dark gray lines are
4) The three trees or shrubs have similar heights, although P parvifolia is clearly a shrub.
5) It is not known whether or not it is in QTP
6) latitude and longitude cannot be read by letter size
Answer: We have modified Figure 3..
(Line:227)
[4] Regarding the use of the aspect, it is measured in degrees and present values between 0 and 360 °, the North exposure varies between 315 and 45º (including 0), while the South exposure between 135 and 215 °. If the values per exposure are averaged, the averages will present similar values at 180º in both exposures. To avoid these errors (And the error that an aspect of 1 ° is totally opposite to 359 °, but at the same time, it is very similar), its important to convert the aspect in degrees by the sine and cosine function into two variables: north-south (ExN) and east-west (ExE). Sine values range from -1 (west) to 1 (east), while cosine values range from -1 (south) to 1 (north).
Answer: In this study, we used aspect as category data for model simulation.
[5] Line 9: Chengdu610041 change to Chengdu 610041..
Answer: We have modified.
[6] Line 37: ),. change to ).
Answer: We have modified.
[7] Line 40: Qinghai–Tibetan Plateau change to Qinghai-Tibetan Plateau
Answer: We have modified.
[8] Line 104: the legend of the Figure does not express the content.
Answer: We have modified the legend of the Figure.
[9] Line 203: , change to and
Answer: We have modified.
Reviewer 2 Report
diversity-1512651-peer-review-v1
Dear Editor,
The manuscript deals with an interesting topic in an ecological important area. The paper is fairly good written, with some minor mistakes. My main concern is the validity of results, which is a bit dubious in every study dealing with future ecosystems. The discussion section should have a separate paragraph or section discussing the limitations of data, modelling and the timespan of the predictions. Therefore I suggest a minor revision.
Specific comments:
The abstract and conclusions are a bit too technical. Too many abbreviations. The conclusion could also states some future research needed – how should be the modelling improved or how and when should be the results analyzed, checked?
l.42: recently? The refrence is from 2000 which was 20 yeaers ago.
l.45-55: I am missing some information on the distribution of these plants outside the Tibetan plateau and Qinghai. Are they endemites, are they threatened or protected? I suppose that the Picea crassifolia is a common tree species in the whole area?
l.50: Sentences should not start with „S.“ but with the full name „Sabina“.
40 and 83-84: are there any other famous words for thea area? Some explanation on the importance?
96-102: does Maxent use point data or are they calculated for a raster (grid)?
Fig.1: include some towns or something the reader can identify a bit more precise where those locations are.
l.112: most popular? What does that mean in terms of validity or precision?
l.128-131: this sounds like some instructions, the authors should write in past tense.
l.132: „to account“ instead of „delete“?
Table 1: write what the selection mark in the last column means. It could be interpreted as an important variables for modelling, although this is just a preliminary phase, i.e. the variable was just chosen to be included in the modelling process!
Table 1: some variables regarding snow cover were inlcuded? Duration or ammount? I hope the table is not going to be split onto two pages as it is now.
l.158: is the refrence right? Evolution?
l.183: why 8 variables? Why not 10 or 6?
Methods: the authors could explain to the reader how were the occurence data points converted into maps in Fig.3.
l.184: current conditions?
Fig.3: I would be happy to see a bit larger pictures and refrenced 3a, 3b 3c (also in the text)
l.194-210: this is very hard to read. Authors could pick some interesting results or main changes and challenges in the future. All the numbers are in Table 3 anyway so there is no reason to list them in the text.
Thousand in english should be separated by a comma, what are the journal requirements?
The latin names of plant species are often without the „.“ For example line 205 „P crassifolia“. Authors should check english numbers and latin names throughout the manuscript.
l.238: no mention of studying „intersections“ in methods. Authors should explain what they mean in the methods or introduction.
Fig.6 is the only part of the study area where these species intersect? Or is this just an example?
l.255: I think the number 3 in the subsection heading does not look good, use text
l.270-278: these are the main result but these variables affect also insects etc. And I think this is the big shortcoming of this paper, because authors just pretend that they calculated the future (as do most sudies of this type). There are natural disturbances (insect outbreaks, avalanches, forest fires) and human interventions (harvesting, grazing, mining etc.) and these are not accound for at all! At least a honest section on the limitation of the study would be good. There are at least two species of bark beetles attacking the spruce in Qinqhai, the Ips shangrila and Ips nitidus. What could be the effects of increasing tempretures on pests? Avalanches? Solar radiation (more or less clouds?)? I think the authors did a pretty good job, the paper is quite polished, but the shortcoming of this approach, when some potential models are modelled and distributions are calculated and presented as facts must be also discussed.
Another part of discussion should be devoured to impacts of these changes? Is it good that spruce will move higher? Does it matter for the other species modelled? Will they disappear from the area? Are they important for local people (grazing, medicine…).
l.287: “...changes...three model species...“
305-306: which factors?
As I said, the conlcusion is too technical. Not every reader is familiar with bio3, bio14 variables etc. Authors should give us a nice conlcusion, written in clear language what did find out and what they did not (disturbances etc.).
All the best.
Author Response
Dear Reviewer:
On behalf of my co-authors, thank you very much for your email with the reviewers’ comments regarding our manuscript. We are highly appreciating the reviewers’ positive and constructive comments and suggestions on our manuscript entitled “The influence of climate change on three dominant alpine species under different scenarios on the Qinghai-Tibetan Plateau” (diversity-1512651). We have carefully revised the manuscript and now submit the new version according to the reviewers’ comments. Our incorporation of the comments is explained point-by-point as follows:
[1] The abstract and conclusions are a bit too technical. Too many abbreviations. The conclusion could also state some future research needed – how should be the modelling improved or how and when should be the results analyzed, checked?
Answer: We have removed some abbreviations, such as Bio4, Bio12, Bio14, S_CEC_CLAY, S_BULK_DEN and S_CEC_SOIL in the abstract and conclusions.
The conclusions have stated some future research needed as follows: However, our research only used the friendly MaxEnt model without considering other models. In future studies, we will select the ensemble model which can reduce the model’s uncertainty to further predict species distribution. (Lines:362-365)
[2] l.42: recently? The refrence is from 2000 which was 20 yeaers ago.
Answer: We have deleted the sentence “And it has also experienced warming recently.”
[3] l.45-55: I am missing some information on the distribution of these plants outside the Tibetan plateau and Qinghai. Are they endemites, are they threatened or protected? I suppose that the Picea crassifolia is a common tree species in the whole area?
Answer: We have added the information on the distribution of these plants as follows: Picea crassifolia habitats on the shady slopes, semi shady slopes and humid valleys in the mountains with an altitude of 1750-3100 m (a.s.l), and it is endemic to China, dis-tributed in Qilian Mountains, Qinghai, Gansu, Ningxia, Inner Mongolia. Sabina przewalskii grows on the sunny slope of 2600-4000 m (a.s.l), and it is endemic to China, dis-tributed in Qinghai, Gansu Hexi Corridor, and the north of Sichuan. Potentilla parvifolia favorites dry hillside, rock crack, forest edge and forest with altitude of 900-5000 m (a.s.l), and it is distributed in Heilongjiang, Inner Mongolia, Gansu, Qinghai, Sichuan and Tibet in China. (Lines:50-56)
[4] l.50: Sentences should not start with „S.“ but with the full name „Sabina“.
Answer: We have used full name.
[5] L40 and 83-84: are there any other famous words for the area? Some explanation on the importance?
Answer: We have added the information as follows: with the highest and one of the most extensive plateaus on earth. (Line:88)
[5] L 96-102: does Maxent use point data or are they calculated for a raster (grid)?
Answer: The longitude and latitude of the distribution data and the species name was entered into Excel, and converted to csv format for modelling. (Lines:106-107) They don't need to calculate for a raster (grid).
Fig.1: include some towns or something the reader can identify a bit more precise where those locations are.
Answer: We have modified figure1 and added provincial boundaries. (line:108)
[5] l.112: most popular? What does that mean in terms of validity or precision?
Answer: We have changed the sentence as follows: which is available for predicting the global climate response to increasing greenhouse gas concentration. (Lines:117-118)
[6] l.128-131: this sounds like some instructions, the authors should write in past tense.
Answer: We have changed to past tense. (Lines:135-136)
[6] l.132: „to account“ instead of „delete“?
Answer: We have changed delete to account.
Table 1: write what the selection mark in the last column means. It could be interpreted as an important variables for modelling, although this is just a preliminary phase, i.e. the variable was just chosen to be included in the modelling process!
Answer: We have changed “Selection” into “Important variables for modelling”. (Line:138)
Table 1: some variables regarding snow cover were inlcuded? Duration or ammount? I hope the table is not going to be split onto two pages as it is now.
Answer: Table 1 has been changed (Line:172), but some variables regarding snow cover were not included.
[7] l.158: is the refrence right? Evolution?
Answer: The reference has been changed. (Line:165)
[8] l.183: why 8 variables? Why not 10 or 6?
Answer: Because we selected the variables whose contribution rate for three species are more than 0.1 for analysis. We have already explained in the paper. (Lines:181-182)
Methods: the authors could explain to the reader how were the occurence data points converted into maps in Fig.3.
Answer: The methods were added in the paper as follows: The asc format files in the model result were converted the raster format and reclassified into four suitable habitats. (Lines:162-163)
[9] l.184: current conditions?
Answer: We have changed to current climate scenarios. (Line:205)
Fig.3: I would be happy to see a bit larger pictures and refrenced 3a, 3b 3c (also in the text)
Answer: We have modified figure3. (Line:227)
[10] l.194-210: this is very hard to read. Authors could pick some interesting results or main changes and challenges in the future. All the numbers are in Table 3 anyway so there is no reason to list them in the text.
Answer: We have rewritten this paragraph as follows:
There were significantly differences in the distribution area of low suitable habitat, moderately suitable habitat and high suitable habitat under future climate scenarios as compared to current. The high suitable habitat for Picea crassifolia decreased under SSP2.6, SSP4.5 and SSP8.5 in 2070s. Especially, the high suitable habitat for Sabina przewalskii declined to zero under SSP8.5 in 2050s. The total suitable habitat for three species all decreased under SSP8.5 in 2050s. The total suitable habitat for Picea crassifolia shrank under SSP2.6, SSP4.5 and SSP7.0 and enlarged under SSP8.5 in 2070s. On the contrary, the total suitable habitat for Sabina przewalskii enlarged under SSP2.6, SSP4.5 and SSP7.0 and shrank under SSP8.5 in 2070s. The total suitable habitat for Potentilla parvifolia continued increasing from SSP2.6 to SSP8.5 in 2070s (Table 3). (Lines:213-222)
[11] Thousand in english should be separated by a comma, what are the journal requirements?
Answer: We have modified the number form.
[12] The latin names of plant species are often without the „.“ For example line 205 „P crassifolia“. Authors should check english numbers and latin names throughout the manuscript.
Answer: We have modified the latin names of plant species throughout the manuscript.
[13] l.238: no mention of studying „intersections“ in methods. Authors should explain what they mean in the methods or introduction.
Fig.6 is the only part of the study area where these species intersect? Or is this just an example?
Answer: The calculation of the intersection distributions has been added to the method as follows: The intersection distributions of the three species were obtained through the raster calculator and extract by attributes tools. (Lines:167-169)
We have explained why select the part of study area in the text as follows: Due to large distribution area in the northeastern of QTP for three species, we analyzed the changes of intersection distributions for three species under future climate scenarios. (Lines:260-261)
[14] l.255: I think the number 3 in the subsection heading does not look good, use text
Answer: We have changed 3 to three. (Lines:259,277,309)
[15] l.270-278: these are the main result but these variables affect also insects etc. And I think this is the big shortcoming of this paper, because authors just pretend that they calculated the future (as do most sudies of this type). There are natural disturbances (insect outbreaks, avalanches, forest fires) and human interventions (harvesting, grazing, mining etc.) and these are not accound for at all! At least a honest section on the limitation of the study would be good. There are at least two species of bark beetles attacking the spruce in Qinqhai, the Ips shangrila and Ips nitidus. What could be the effects of increasing tempretures on pests? Avalanches? Solar radiation (more or less clouds?)? I think the authors did a pretty good job, the paper is quite polished, but the shortcoming of this approach, when some potential models are modelled and distributions are calculated and presented as facts must be also discussed.
Another part of discussion should be devoured to impacts of these changes? Is it good that spruce will move higher? Does it matter for the other species modelled? Will they disappear from the area? Are they important for local people (grazing, medicine…).
Answer: We have added a paragraph to discuss the influence of other factors on the potential distribution of three species as follows: In addition, the two Ips species (Ips nitidus Eggers and Ips shangrila Cognato and Sun) are the most destructive secondary bark beetles on P. crassifolia and always cause mortality of trees by their cooperation (Liu et al., 2008). Increasing human interven-tions, such as harvesting, grazing and mining, may also result in distribution changes of the three species. The human population on the QTP has expanded dramatically in the past decades. Some suitable habitats for alpine species were converted to other land uses, such as pastures or settlement (Yang et al., 2018). (Lines:343-349)
[16] l.287: “...changes...three model species...“
Answer: We have modified. (Line:309)
[17] 305-306: which factors?
Answer: We have added a part of discussion to explain other factors. (Lines:343-349)
[18] As I said, the conclusion is too technical. Not every reader is familiar with bio3, bio14 variables etc. Authors should give us a nice conclusion, written in clear language what did find out and what they did not (disturbances etc.).
Answer: We have rewritten the conclusion. (Lines:351-365)
