Spatiotemporal Ecology of an Imperiled Cushion Plant Assemblage at a North American Rocky Mountain Summit: Implications for Diversity Conservation

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

The study by aimed to characterize the environment and botanical composition of sites with presence of endangered cushion plant species at a popular mountain summit in Wyoming. I find that the manuscript is well written and presents a brief and concise introduction regarding the need for studies that consider detailed data on the distribution and environmental associations of endangered cushion plant species and then proceeds to describe the methodological procedures and results in detail. I found the results very interesting and compelling, regardless, I have some some major comments which I feel would strengthen the manuscript. 

Major Comments:

1) The authors state four research objectives, but do not frame their work under an overarching goal or mechanistic hypothesis, which would strengthen the manuscript and provide greater guidance for the readers. In this context, it would be interesting if the authors stated what would be the expected associations of the focal species they wish to understand. Would they be expected to be associated with less disturbed habitats? Or areas with less presence of exotic species? Above a certain elevation or vegetation formation threshold? I believe this can be addressed by the authors and would provide a huge improvement to the manuscript.

2) The method section is clear and concise. However, given the scope of the journal, I would suggest the authors consider including either a reference map or a satellite imagery illustrating the location of the study area, and location of the study plots, particularly regarding elevation. This would allow readers to gain a better insight as to the potential drivers modulating the distribution and abundance of species studied.

3) In addition, I would suggest that the authors consider providing any available information regarding the elevation limits of the species considered in the study, and recorded habitats associations as well. this would be nice particularly if it ties in with any potential hypothesis that may be stated. Please note that if this information is not available in the literature, it would be important to state so, with the corresponding literature references to support these claims, as this would make this an even stronger contribution. 

4) Please note that according to the Kew Royal Botanic Gardens Plants of the World Online database, and the Global Biodiversity Information Facility, Arenaria hookeri is a synonym of Eremogone hookeri. Please revise the information in Table 1, particularly regarding the conservation status (see https://explorer.natureserve.org/Taxon/ELEMENT_GLOBAL.2.157523/Eremogone_hookeri). The same applies for Castilleja angustifolia, which seems to be a synonym for Castilleja integra, as well as for  Leucopoa kingii (synonym of Festuca kingii) and Minuartia nuttallii (synonym of Sabulina nuttallii). 

5) While the Introduction is well structured, I would suggest that the authors would consider some information regarding the potential effects of invasive species as a result of human visitors or unsustainable tourism practices. In addition, some of the points indicated in the closing paragraph of the discussion section would have been valuable in setting the relevance and reach of the paper, so it would have been nice to see them mentioned in the introduction. This would give the authors room to elaborate on these topics in the discussion. I would have loved to see some discussion of whether the observed trends are in line with a lack of climate change effects on the study sites, and whether the species are present with exotic or invasive species as well. 

Please see the following minor comments

Minor comments:

Please revise the use of italics for scientific names is consistent throughout the manuscript, as some sections of the text present scientific names without italic text (e.g. Result section, specifically lines 158 to 170 and 183 to 187).

Lines 69 to 71: The phrase "All three species have been classified as a ‘species of concern’ by the Wyoming Natural Diversity Database but there overlap in distribution is currently not well defined." Should be edited. I suggest editing it to "All three species have been classified as a ‘species of concern’ by the Wyoming Natural Diversity Database but their overlap in distribution is currently not well defined."

Line 72: The phrase "A. aromatica is a potential species concern ..." does not make sense. I would suggest editing it to "A. aromatica is a species of potential concern ..."

 

Author Response

We have carefully considered the comments from the three Reviewers and have found them to be very constructive and helpful.  We have incorporated all suggestions to some degree with itemized and detailed responses below.  Each Reviewer comment is underlined and our response begins with ‘AUTHOR RESPONSE’.  

The study by aimed to characterize the environment and botanical composition of sites with presence of endangered cushion plant species at a popular mountain summit in Wyoming. I find that the manuscript is well written and presents a brief and concise introduction regarding the need for studies that consider detailed data on the distribution and environmental associations of endangered cushion plant species and then proceeds to describe the methodological procedures and results in detail. I found the results very interesting and compelling, regardless, I have some some major comments which I feel would strengthen the manuscript.

1. The authors state four research objectives, but do not frame their work under an overarching goal or mechanistic hypothesis, which would strengthen the manuscript and provide greater guidance for the readers. In this context, it would be interesting if the authors stated what would be the expected associations of the focal species they wish to understand. Would they be expected to be associated with less disturbed habitats? Or areas with less presence of exotic species? Above a certain elevation or vegetation formation threshold? I believe this can be addressed by the authors and would provide a huge improvement to the manuscript.
1. AUTHOR RESPONSE: This is a fair set of questions but unfortunately this work is perhaps more descriptive than hypothesis driven based on the limited amount of information available about these plant species and assemblages.  Moreover, we do not have details about disturbance and until now had no data about exotic species presence or abundance in these habitats.  In addition, we did not do complete altitudinal inventory to attempt to determine elevational thresholds.  Lawton (199) stated that community ecology is “a mess” and this manuscript represents a first attempt at describing this mess which will then lead to more mechanistic work.  We believe some of our clarifications about objectives help to address and articulate our overarching goals for this study.
2. The method section is clear and concise. However, given the scope of the journal, I would suggest the authors consider including either a reference map or a satellite imagery illustrating the location of the study area, and location of the study plots, particularly regarding elevation. This would allow readers to gain a better insight as to the potential drivers modulating the distribution and abundance of species studied.
1. AUTHOR RESPONSE: We have prepared a figure with Heart Mountain location, landscape view and satellite imagery of macroplots. More details about them, including elevation, are reported in Table 1.  This new figures is now Figure 2 and we have adjusted all figure numbers in the manuscript.
3. In addition, I would suggest that the authors consider providing any available information regarding the elevation limits of the species considered in the study, and recorded habitats associations as well. this would be nice particularly if it ties in with any potential hypothesis that may be stated. Please note that if this information is not available in the literature, it would be important to state so, with the corresponding literature references to support these claims, as this would make this an even stronger contribution.
1. AUTHOR RESPONSE:  This is an important suggestion.  We checked the literature and found elevation limits for 2 of the 3 species.  We did not find robust descriptions of habitat associations – rather most of the literature is devoted to the taxonomic characteristics and/or inventories of single species.  We have provided these ranges in the Materials and Methods section (“This search was conducted within the reported elevation ranges of 1,372-2,928 m for A. aromatica [22,23] and 1,770-2,780 m for S. pulvinata [24,26].  No reported ranges were found in the literature for E. howardii.”) and point out the lack of species or habitat associations (“Even though these three rare cushion plant species were generally described by Heidel in 2012 [21], with robust consideration for taxonomy [22-25,29] with a few referencing their elevational ranges, there are none describing species associations which is extremely important for their conservation.”).
4. Please note that according to the Kew Royal Botanic Gardens Plants of the World Online database, and the Global Biodiversity Information Facility, Arenaria hookeri is a synonym of Eremogone hookeri. Please revise the information in Table 1, particularly regarding the conservation status (see https://explorer.natureserve.org/Taxon/ELEMENT_GLOBAL.2.157523/Eremogone_hookeri). The same applies for Castilleja angustifolia, which seems to be a synonym for Castilleja integra, as well as for  Leucopoa kingii (synonym of Festuca kingii) and Minuartia nuttallii (synonym of Sabulina nuttallii).
1. AUTHOR RESPONSE: This is an important suggestion. We do note that we refer to the USDA Plant Database (https://plants.usda.gov/home) for taxonomic nomenclature and authority and we have double checked all scientific names in the USDA Plant Database for this revision. 
2. When we compare names and synonyms between our primary reference to the references provided above we do note disagreements.  As a decision making criteria, we referred to both the USDA Plant Database and the NatureServe database for buffalograss (Bouteloua dactyloides) which has recently undergone such taxonomic adjustments (from the Buchloe genera to Bouteloua) with reference to Columbus (1999).  Considering that the most contemporary treatment places this species in the genera Bouteloua, and as such, USDA Plant Database names this as Bouteloua dactyloides with reference to the outdated synonym of Bucholoe dactyloides (which is correct in our modest opinion), whereas NatureServe uses the primary name in the opposite order (Buchloe dactyloides as primary and Bouteloua dactyloides as synonym).  There is also reason to take issue with the Kew Royal Botanic Garden as it still presents names for buffalograss similar to NatureServe but is not up to date for other known species adjustments, notably for tall fescue (another species that has been changed; it still lists the genera as Festuca with Lolium as a synonym with no reference to Schedonorus which is the most modern and accepted genera for this species).  As a one more relevant example, Leucopoa kingii in the USDA Plant Database is the primary name with 4 synonyms including the 3 different genera (Festuca, Hesperochloa, and Poa).  So, we prefer the current presentations following USDA Plant Database but do agree the names presented above should be listed as synonyms and have updated this Table with the synonyms in the footnotes. We certainly would be open to more discussion or direction if needed on this important point.
3.  Columbus, J. T. (1999). An expanded circumscription of Bouteloua (Gramineae: Choridoideae): new combinations and names. Aliso: A Journal of Systematic and Floristic Botany, 18(1), 61-65.
5. While the Introduction is well structured, I would suggest that the authors would consider some information regarding the potential effects of invasive species as a result of human visitors or unsustainable tourism practices. In addition, some of the points indicated in the closing paragraph of the discussion section would have been valuable in setting the relevance and reach of the paper, so it would have been nice to see them mentioned in the introduction. This would give the authors room to elaborate on these topics in the discussion. I would have loved to see some discussion of whether the observed trends are in line with a lack of climate change effects on the study sites, and whether the species are present with exotic or invasive species as well.
1. AUTHOR RESPONSE:  We agree and it seems we did not do a sufficient job pointing this out here and note that the references supporting the statements in the second paragraph of the Introduction section do suggest that tourism and recreation can lead to exotic and invasive species introductions; and that designing such access should incorporate a better understanding of invasive species ecology and ecological resistance. 
2. We have edited to emphasize some of the points from the final paragraph of the Discussion section including that this is a global phenomenon and that there may cascading ecological effects.
3. We have elaborated more with 2 new sentences here.  To the last point, we did not find any exotic or invasive species in our plots so we have addressed this in the manuscript and it was one of our objectives.

 

Minor comments:

1. Please revise the use of italics for scientific names is consistent throughout the manuscript, as some sections of the text present scientific names without italic text (e.g. Result section, specifically lines 158 to 170 and 183 to 187).
1. AUTHOR RESPONSE: We applied italics for all scientific names along the text. Thank you.
2. Lines 69 to 71: The phrase "All three species have been classified as a ‘species of concern’ by the Wyoming Natural Diversity Database but there overlap in distribution is currently not well defined." Should be edited. I suggest editing it to "All three species have been classified as a ‘species of concern’ by the Wyoming Natural Diversity Database but their overlap in distribution is currently not well defined."
1. AUTHOR RESPONSE: Thank you. We followed your suggestion.   
3. Line 72: The phrase "A. aromatica is a potential species concern ..." does not make sense. I would suggest editing it to "A. aromatica is a species of potential concern ..."
1. AUTHOR RESPONSE: Thank you. We followed your suggestion.   

Reviewer 2 Report

Comments and Suggestions for Authors

According to the title of the manuscript, Derek-Scasta and Forster-Furquim aimed to characterize the spatiotemporal variation of plant communities on a North American Rocky Mountain summit and discuss the implications of their findings for plant diversity conservation in areas with ecotourism activities. While the study attempts to generate relevant knowledge, I believe it has significant limitations that prevent its publication in its current form. One of the main limitations is the lack of clear objectives, which are sometimes contradictory throughout the document, as well as the absence of well-defined working hypotheses. This results in an introduction, methodology, and discussion that lack direction, cohesion, and strong justification.

 

Specific points for improvement:

Although the manuscript presents itself as a community-level analysis, it seems to focus more on the populations of three specific species. It is crucial to clearly define the study's focus and, if necessary, justify the inclusion of both levels of integration.

 

Justify why three years are deemed sufficient to detect population changes attributed to ecotourism activities.

 

Explain how the design allows the assessment of ecotourism impacts, substantiating conclusions regarding their effects on communities and populations.

 

Provide a rationale for the selection of predictors used in the analyses, grounded in the species' natural history and their potential responses to ecotourism-related environmental changes.

 

Ensure that selected predictors exhibit relevant variation to evaluate their effects.

 

The lack of clear hypotheses has led to poorly justified analyses (e.g., species diversity indices). I recommend formulating explicit hypotheses to guide the analyses.

 

Provide key methodological details. For instance, clarify in line 122 whether individuals were randomly selected within each macroplot to estimate canopy height.

 

If the three macroplots represent different conditions, evaluate sampling completeness separately for each.

 

Account for the spatial structure in the analyses, as quadrats are nested within macroplots. Some analyses (ANOVA) treat sites as homogeneous, whereas others (CCA) acknowledge this variation.

 

Clarify whether sampling methods were consistent across years and whether environmental parameters were measured annually.

 

Reassess the relevance of redundant columns, such as G and O in Table 2. Avoid presenting the same information twice (lines 184-185).

 

Comments on the Quality of English Language

I recommend conducting an in-depth revision of the manuscript to achieve a clearer and more concise writing style, where the main ideas are easy to identify. During the revision, I suggest focusing on using short, direct sentences, to effectively present the core ideas.

Author Response

We have carefully considered the comments from the three Reviewers and have found them to be very constructive and helpful.  We have incorporated all suggestions to some degree with itemized and detailed responses below.  Each Reviewer comment is underlined and our response begins with ‘AUTHOR RESPONSE’.  

According to the title of the manuscript, Derek-Scasta and Forster-Furquim aimed to characterize the spatiotemporal variation of plant communities on a North American Rocky Mountain summit and discuss the implications of their findings for plant diversity conservation in areas with ecotourism activities. While the study attempts to generate relevant knowledge, I believe it has significant limitations that prevent its publication in its current form. One of the main limitations is the lack of clear objectives, which are sometimes contradictory throughout the document, as well as the absence of well-defined working hypotheses. This results in an introduction, methodology, and discussion that lack direction, cohesion, and strong justification.

1. Although the manuscript presents itself as a community-level analysis, it seems to focus more on the populations of three specific species. It is crucial to clearly define the study's focus and, if necessary, justify the inclusion of both levels of integration.
1. AUTHOR RESPONSE:  This is a good point and ambitiously, this study therefore seeks to address populations of three rare species but also explore community-level interactions.  We have clarified this at the end of the Introduction section.
2. Justify why three years are deemed sufficient to detect population changes attributed to ecotourism activities.
1. AUTHOR RESPONSE:  Three years is likely insufficient but it is a starting point to assess if any changes are occurring.  We had added the following sentence in the first paragraph of the Introduction “However, three years has admittedly limited temporal insight to detect population changes.” And then suggest that annual monitoring is needed in order to determine such effects.
3. Explain how the design allows the assessment of ecotourism impacts, substantiating conclusions regarding their effects on communities and populations.
1. AUTHOR RESPONSE: It provides insight during the period of study but does not give long-term insights relative to the history of the site.  We believe we have now addressed this.
4. Provide a rationale for the selection of predictors used in the analyses, grounded in the species' natural history and their potential responses to ecotourism-related environmental changes.
1. AUTHOR RESPONSE:  We agree and have added the following sentence “Selection of predictors used in the analyses was based on the species' natural history [21-29] and the potential environmental alterations attributed to ecotourism [1,6,8,10-13].”
5. Ensure that selected predictors exhibit relevant variation to evaluate their effects.
1. AUTHOR RESPONSE: We have added the following information to show the variation and gradient of each in our study: “Gradients for these environmental predictors were as follows: vegetative cover (5 to 52%), standing dead biomass (0 to 10%), rock (10 to 93%), litter (0 to 15%), bare soil (0 to 60%), canopy height (0.25 to 10.2 cm), and altitude (2301 to 2478 m).”
6. The lack of clear hypotheses has led to poorly justified analyses (e.g., species diversity indices). I recommend formulating explicit hypotheses to guide the analyses.
1. AUTHOR RESPONSE:  Because this study is both descriptive and guided by hypothesis we included both types of approaches.  We believe the more clearly defined language at the end of the Introduction section helps to address this relevant concern.
7. Provide key methodological details. For instance, clarify in line 122 whether individuals were randomly selected within each macroplot to estimate canopy height.
1. AUTHOR RESPONSE: Yes, individuals were randomly selected. We now included this information in the text.
8. If the three macroplots represent different conditions, evaluate sampling completeness separately for each.
1. AUTHOR RESPONSE:  Please see our description in the Materials and Methods section where we describe our species accumulation curves to determine sampling completeness which suggests that “our 3 macroplots with a total of 24 quadrats was robust for sampling effort and desired species detection” with Figure 2 demonstrating this effort.
9. Account for the spatial structure in the analyses, as quadrats are nested within macroplots. Some analyses (ANOVA) treat sites as homogeneous, whereas others (CCA) acknowledge this variation.
1. AUTHOR RESPONSE:  We have re-run the analyses for (1) the annual means of the three rare species as shown in Figure 3 and (2) richness, evenness, and diversity as shown in Figure 4 using the lmer function in R for linear mixed models with quadrat nested within macroplot as a random effect.  We also replaced a reference here to provide a book chapter that talks about nested models and the lmer function.
2. Dean, A.; Voss, D.; Draguljić, D.; Dean, A.; Voss, D.; Draguljić, D. (2017). Chapter 18 - Nested Models. In: Design and Analysis of Experiments, 2nd Edition. Springer Texts in Statistics. https://doi.org/10.1007/978-3-319-52250-0_18
3. For results in Figure 3, the only p-value that changed was for E. howardii but it did not result in any changes of significance or interpretation of the data.
4. For results in Figure 4, the only p-value that changed was for Diversity but it did not result in any changes of significance or interpretation of the data.
5. We have updated the text to reflect these changes.
10. Clarify whether sampling methods were consistent across years and whether environmental parameters were measured annually.
1. AUTHOR RESPONSE:  Indeed sampling was consist across years and environmental parameters were measured annually.  We have added this clarification to the second paragraph in the Materials and Methods section.
11. Reassess the relevance of redundant columns, such as G and O in Table 2. Avoid presenting the same information twice (lines 184-185).
1. AUTHOR RESPONSE:  We have removed Columns G and O and added the this to the Table caption in place of that information that states “All species are native perennials…”.  We are not clear about what the Reviewer thinks is the presentation of the same information twice in Lines 184-185 as those 2 lines simply present the abundance for the 3 species.  If more clarification is provided we can consider editing. 

 

Comments on the Quality of English Language

1. I recommend conducting an in-depth revision of the manuscript to achieve a clearer and more concise writing style, where the main ideas are easy to identify. During the revision, I suggest focusing on using short, direct sentences, to effectively present the core ideas.
1. AUTHOR RESPONSE:  We agree and have done an in-depth revision of the manuscript as suggested.

 

Reviewer 3 Report

Comments and Suggestions for Authors

all in the MS

Comments for author File: Comments.pdf

Author Response

We have carefully considered the comments from the three Reviewers and have found them to be very constructive and helpful.  We have incorporated all suggestions to some degree with itemized and detailed responses below.  Each Reviewer comment is underlined and our response begins with ‘AUTHOR RESPONSE’. 

1. or Spatiotemporal??? 
1. AUTHOR RESPONSE: Spatiotemporal fits better so we have added that.
2. order in alphabetic way
1. AUTHOR RESPONSE: Reordered. Thank you.
3. Reference here¡¡¡
1. AUTHOR RESPONSE:  We have combined the first two sentences for clarity and point to the first reference in the paper as support of this introductory comment.
4. is not equal as the title?. Make sure the title and objective are the same with the same wording
1. AUTHOR RESPONSE:  We have edited accordingly and these are now in very close alignment.  Thank you for this suggestion.
5. Are all the research objectives includen in the ABSTRACTS their results????
1. AUTHOR RESPONSE: We believe so and have provided a point by point assessment below:
6. (1) Quantify plant community diversity and determine if exotic species invasion or other rare plants were of concern; Abstract states: “Nineteen total plant species were identified, all of which were native perennial species. Five additional species were also noted to be species of conservation concern.” 
7. (2) Determine if rare species abundance and overall plant species richness, evenness, and diversity were stable through time over a three year period; Abstract states: “For the three focal rare cushion plants, abundance did not significantly change over the three-year period. Species richness was lower in 2017 than subsequent years but there was no difference of evenness or diversity.” 

• (3) Quantify the habitat preferences of each rare plant species and determine if niche separation occurred; Abstract states: “In the constrained ordination, the first axis explained 56.1% of the variation and was attributed to the rock-to-vegetation gradient of the environment while the second axis explained an additional 28.7% of the variance and was attributed to altitude. The three focal rare cushion plants appeared to segregate and occupy differential habitat niches.” 

1. (4) Provide insight for future management to optimize botanical diversity conservation and societal awareness. Abstract states: “The popularity of this mountain summit, coupled with the presence of a diverse rare cushion plant community, should facilitate careful monitoring and management of tourism to ensure conservation of diversity.”

1. this results are in rthe ABSTRACTS
1. AUTHOR RESPONSE: Yes and please see our clarification of this point above.
2. why not 9???
1. AUTHOR RESPONSE: We sampled 6 plots each year in macroplot 1, which had the smallest area compared to others macroplots, mainly due to access restriction given the rugged terrain.  We have added an asterisk and a footnote to this table with this clarification.
3. why are not  all these variables in the Abstracts
1. AUTHOR RESPONSE: We have checked this and corrected this; they are all there now. 
4. Ethic aspects: ???
1. AUTHOR RESPONSE: Great question and we have addressed conflicts of interest at the end of the manuscript (after Author Contributions, Funding, Data Availability Statement, and Acknowledgements).
5. not italics for all families
1. AUTHOR RESPONSE: Fixed.
6. but richness change between years???
1. AUTHOR RESPONSE: Thanks for your observation. We rewrote this sentence as follows: “Except for plant species richness, which was higher in the first survey than others, the general abundance of the three focal rare cushion plant species, as well as all metrics of richness, evenness, and diversity, appeared to be stable during our three year period of study.”