Seed Sourcing Strategies Considering Climate Change Forecasts: A Practical Test in Scots Pine

Round 1

Reviewer 1 Report

This is a novel paper which analyses for the first time different seed sourcing strategies for Scots pine under climate change scenarios using multi-site provenance tests. It is interesting, particularly in the context of the debate regarding assisted migration. 

The abstract should make clear that only high emissions scenarios were used in the analysis. Analysis using other emissions scenarios would have been interesting.

A single species was studied. It cannot be assumed that the findings of this research are applicable to all forest tree species in the rear-edge of distribution. Revise lines 34 and 103.

Line 121 "These markers" - be more specific

Fig. 2 S2 is not shown

Line 233-234 By 2100, none of the populations studied will be suitable for predicted climatic conditions. This is an important finding and should receive much more emphasis and consideration in the discussion, conclusion and abstract. Implications for conservation of genetic diversity (and perhaps wider biodiversity, given the predicted loss of a key component of forest habitat) should be elaborated in the discussion.

Line 235 insert "by 2050"

Line 238 typo - sites

Table 5 caption: insert "up to 2050" and specify which fig./table in Appendix A

p. 8 numerous typos

Discussion is generally well-written.

Line 343 Another, not other

Conclusions: Consideration should be given as to how this research should inform forest policy at national and/or EU level.

Use the term "selection" rather than "election" throughout. 

The plural of index is indices, not indexes.

English language editing is needed.

There are numerous misspellings/typos. 

References need attention (e.g. format of reference 34 & 48, 31 is a duplicate, inconsistent use of capitals in journal article titles, etc.) 

Author Response

We  thank the reviewer for her/his improving comments and interest in the topic, as the text is on language editing progress we answer directly the comments:

The abstract should make clear that only high emissions scenarios were used in the analysis. Analysis using other emissions scenarios would have been interesting. Included in abstract (...under a climate change high emissions scenario using a Scots pine ...) and introduction (...seed sourcing strategies under the climate change high emission scenario RCP 8.5 (business as usual) in order to increase adaptation and resilience of future forests.) DONE

A single species was studied. It cannot be assumed that the findings of this research are applicable to all forest tree species in the rear-edge of distribution. Revise lines 34 and 103. Specification of Scots pine as species is made at both places. DONE

Line 121 "These markers" - be more specific. Now we specify “Chloroplast SSR” instead.  DONE

Fig. 2 S2 is not shown. Now it is included. DONE

Line 233-234 By 2100, none of the populations studied will be suitable for predicted climatic conditions. This is an important finding and should receive much more emphasis and consideration in the discussion, conclusion and abstract. Implications for conservation of genetic diversity (and perhaps wider biodiversity, given the predicted loss of a key component of forest habitat) should be elaborated in the discussion.

We thank the reviewer for this suggestion. We think that even though the current climate change trend is not promising and that we have used the high emissions scenario, this trend should (or must) change in the next decades, and there is a hope for that. The paper temporal objectives are closer than the next century, in fact the seed sourcing strategies are planned to 2050. Nonetheless, the idea and warning message are included in the discussion as follows:

While the time scale of this work comparing strategies of seed sourcing has been set at 2050, it is noteworthy to warn that no provenance will be suitable for the next century if the climate change follows the high emission scenario. This situation has severe implications and negative consequences for the conservation of genetic diversity, not only for Scots pine but also for a wider set of biodiversity when losing a key component of the forest habitat. DONE

Line 235 insert "by 2050" DONE

Line 238 typo - sites DONE

Table 5 caption: insert "up to 2050" and specify which fig./table in Appendix A DONE

1. 8 numerous typos p.8 Language editing is currently being done

Discussion is generally well-written.

Line 343 Another, not other DONE

Conclusions: Consideration should be given as to how this research should inform forest policy at national and/or EU level.

This sentence has been added to the conclusions:

This information should be taken into account in forest policies at national and/or EU level by adapting the transfer guidelines of FRM as in the ones provided by EUFORGEN (ref.). In Spain, the National Strategy of FGR (ref.) should take into consideration those results in order to improve the recommendations for future climatic scenarios.

Use the term "selection" rather than "election" throughout. DONE

The plural of index is indices, not indexes. DONE

English language editing is needed. Language editing is currently being done

There are numerous misspellings/typos.  Language editing is currently being done

References need attention (e.g. format of reference 34 & 48, 31 is a duplicate, inconsistent use of capitals in journal article titles, etc.) References have been checked and corrected DONE

The English is being edited by a professional scientific English editor (P. Grant). (Corrections pending)

Reviewer 2 Report

Authors performed bootstrapping analysis to test six different seed sourcing strategies under a climate change scenario using provenance test sites of scots pine in Spain.
The paper is well-written and I have only one general question and some few specific comments. 

Results of this study are based on simulated data from a few provenances and a few test sites. Do authors expect similar results based on real measurements from more tested materials?

 specific comments: 
Line 28: put a comma after height.

Line 142: It is good to write the fitted mixed-model in a mathematical format.

Line 209: Are correlations reported in Table 2 based on all sites? How the correlations were obtained?

Line 237: What do authors exactly mean by (17) ? is it provenance 17?

Lines 237 to 239: words in the sentences have some spelling issues and this part needs to be elaborated.

Line 244: add “a” to sjusted.

Line 265: 4 in S45  should be removed.

Comments for author File: Comments.docx

Author Response

We thank the reviewer for her/his improving comments and interest in the topic, as the text is on language editing progress we answer directly the comments

Authors performed bootstrapping analysis to test six different seed sourcing strategies under a climate change scenario using provenance test sites of Scots pine in Spain.
The paper is well-written and I have only one general question and some few specific comments. 

Results of this study are based on simulated data from a few provenances and a few test sites. Do authors expect similar results based on real measurements from more tested materials?

The input data we used included a comprehensive set of testing sites and provenances, at least considering average multi-site common garden experiments in Spain. In that sense, we believe it is difficult to provide a more complete example at present time.

Of course, it would be interesting and valuable to widen the number of testing sites and provenances using de novo trials that included sites and populations in a much wider area of Scots pine distributions range. Maybe this could be an interesting example to be developed in collaboration with researched from other countries. In any case, as we are aware of such limitation, we included in the text a caveat explaining that Spanish Scots pine populations may not be comparable to northern ones.

Nonetheless, the simulations we performed are based on raw data from real testing sites. What changed at each simulation is which individual trees were chosen to be part of each n= 50 simulated population. In that sense, we believe that our expectations are solid regarding Scots pine in Spain and to a lesser extent, to other species at their rear-edge of distribution.

 Specific comments: 

Line 28: put a comma after height. DONE

Line 142: It is good to write the fitted mixed-model in a mathematical format. DONE with:

Then, we performed a combined analysis of sites using spatially-corrected individual measurements [18] according to the model:

Yijkl = μ + Si x Pj + B(S)k + U(S/B)l + eijkl

where, Y is the vector containing the variable values, μ is the general mean, S the study site, P the provenance, B the block within site, U the experimental unit within block and site, which consists of four contiguous trees,  and e is the random error term. All variables were coded as random.

Significance of random factors was tested by means of Likelihood Ratio Tests (LRTs). We also obtained age-age correlations and trait correlations at the individual tree level after corrections

Line 209: Are correlations reported in Table 2 based on all sites? How the correlations were obtained?

Yes, table 2 contains above diagonal correlations based on mean sites (all sites considered) and below diagonal at individual level. Data used for correlations is after spatial correction described in material and methods in order to remove fine-scale spatial variation and generate phenotypic data devoid of that source of variation

Line 237: What do authors exactly mean by (17) ? is it provenance 17? Yes, DONE

Lines 237 to 239: words in the sentences have some spelling issues and this part needs to be elaborated. Language revision is being done

Line 244: add “a” to sjusted. DONE

Line 265: 4 in S45  should be removed. DONE