Role of Plant Traits in Photosynthesis and Thermal Damage Avoidance under Warmer and Drier Climates in Boreal Forests
Round 1
Reviewer 1 Report
In this manuscript the authors applied the APES model to investigate plants traits that are important in regulating leaf temperature and CO2 assimilation in boreal ecosystems. The manuscript is well written and details are provided. My main comments relate to the limitation of the model and study. In the discussion section please add info on the limitation of APES, and limitation of your design i.e., study was only conducted during the growing season (May-Sept), it is important to acknowledge and discuss this limitation of the study and its impacts on the observed results (discuss the role of longer growing season on plant performance; would the change in the length of the growing season offset some of the observed negative impacts?).
Other comments are minor:
Line 2, in title, please change “on” to “in”
L 12, please change “excessive” to “extreme”
L22, please use an alternative wording to “high levels”, perhaps use maintenance of assimilation rates.
L44: define “windy conditions” is there a range or a min?
Figs 3, 4, 5, is it possible to provide a legend for the color theme. These images were hard to follow.
Author Response
Please, find a Point-by-Point document attached in a separate file
Author Response File: 
Author Response.pdf
Reviewer 2 Report
The paper "Role of plant traits on CO2 assimilation and thermal damage avoidance under warmer and drier climates in boreal forests' looked at using a mechanistic model describing energy transfers between soil, plant and atmosphere to identify which combinations of growing conditions and plant traits allow trees to keep high CO2 assimilation rates and prevent thermal damage under climatic changes.
The question of plant trait changes under a warming climate in boreal forests is an interesting one, but sadly I feel this paper falls short.
Comments:
Introduction:
I found the introduction well written, but could with having a clear focus. the story of the paper is not well presented. I like it to be very clear why this paper is important and it needs to be published. This is not clear from the introduction.
Methods:
I found myself having to re-read sections numerous times to get my head around the content. I found the methodology section too convoluted, with far too many acronyms to keep track of.
I will be honest and state I am not an expert in the methodology described in this paper, however that should not stop me from understanding what was undertaken. Unfortunately the methods section needs to be more concise and a lot clearer.
Section 2.3.2 in particular was very difficult to follow. I understand this type of analysis is complicated but the in depth details included make it near impossible to comprehend.
There is no clear mention of what species would be used in the models? The title states boreal forests? But are we to assume they mean trees? Or do they consider understory vegetation? Deciduous, coniferous? This is key information that is missing.
Results:
The quality of the figures is poor. It is impossible to read the labels on the inset boxes in Figure 1
Discussion:
The heavy use of acronyms became especially apparent when trying to understand the discussion and I kept having to refresh my memory as to what they all meant. I understand the glossary of terms was included in the supplementary information but a paper needs to stand alone, and at the moment it falls short.
At the moment the discussion does not really 'discuss' the results and in many places seems to just state the results again and not dig deep into what these results mean in the wider context.
Detailed comments:
Line 11: 'Will need to cope' sounds awkward. Could do with rephrasing.
Lines 30 and 31: References needed for the statement of temperature increases.
Line 33: Relevance to the study?
Line 58: Reference needed "boreal forests are warming up twice as fast as other ecosystems"
Lines 63-71: This section seems repetitive. You have stated on numerous occasions the goal of this paper is currently unexplored.
Line 72: Remove the reference to APES here and just include 'mechanistic model'. You go on to define it in line 86. This is sufficient.
Line 91: Define CO2 acronym
Author Response
Please, find a Point-by-Point document in attachments
Author Response File: Author Response.pdf
Round 2
Reviewer 2 Report
I see a big improvement in this manuscript and it is much easier to read. In particular the methods section is much more accessible.
The discussion overall is much stronger now, especially given the discussion on the limitations of the study.
Small comments:
Line 13: The inclusion of 'damaging high' sounds strange. I would change excessive to extreme.
Key words: CO2 assimilation has been removed and replaced with photosynthesis throughout abstract but the opposite here?
Line 69: Check grammar - Warming together with low water - needs a comma
Line 113: Remove 'To answer the above questions' and just state 'We use the model APES....'
Line 523: The use of the phrase 'In summary' is rather misleading given it's not the end of the discussion. I think this could be removed for clarity.
The sub headings in the discussion are a little confusing. Can they be clearer?
Author Response
Please, find our response Point-by-Point in attachments
Author Response File: Author Response.pdf
