Net Primary Productivity of Forest Ecosystems in the Southwest Karst Region from the Perspective of Carbon Neutralization
Round 1
Reviewer 1 Report
the paper is clear and interesting review, I like the identification and comment on the research perspectives
what I missed is more profound explanation why SE China karst region is so important in terms of forestry
major editorial error - citations are not in MDPI format
other issues (L = line)
key words could be more adequate to the manuscript content, karst is wrong as you do not analyse it at all
L58-59 if inorganic matter is CO2 then "CO2" is not necessary in the equation, similarly C organic
figure 1 - precipitation is usually abbreviated to P
L87-88 you did not analyse karst region but the literature :)
L91-93 these are nice words meaning nothing, redundant fillers (also at the end of the manuscript)
L152 not "nee" but "NEE"
L165 is comprehensive model the same what integrated model form the table 2? if so, the same term should be used
table 2 latent heat of evaporation should be Lr not only L
table 3 caption should explain all abbreviations - none is, correct it
L344 i'm not convinced with this descrition, photosyntesis (rate) rises along the temperature, but only up to certain thershold above each it is too hot for the plant and the rate goes down - this is this optimal temperature from the next sentence; rephrase
L409-410 such detailed accuracy is not necessary
L411 - coeff of variation does not show that variable reaches a certain value, sth is wrong with this sentence
L428 not "vapour pressure difference" but "vapour pressure deficit"
table 5 unify the accuracy, what does "/" mean?
references require addaptation to the guideliness
Author Response
Thank you very much for your constructive and considerate comments. We revised/improved our manuscript carefully according to your suggestions. Details are point-by-point.
Please see the attachment.
Author Response File: 
Author Response.docx
Reviewer 2 Report
Dear authors,
Thank you for your efforts in this exciting investigation.
This article has two different parts.
The first part of this article is a review of methods of NPP assessment. The second part analyses the forest ecosystems' NPP trends in karst areas. I recommend that the authors consider strengthening the connection between both article parts.
The strong point of this research is a very detailed review of methods; however, the weak point is the absence of own data of NPP research.
I recommend reviewing one more method for assessing NPP to improve the article. Authors can read:
1. Shvidenko A, Schepaschenko D, Nilsson S, Bouloui Y (2007) Semi-empirical models for assessing biological productivity of northern Eurasian forests. Ecol Model 204:163–179
2. Lesiv, M., Shvidenko, A., Schepaschenko, D. et al. A spatial assessment of the forest carbon budget for Ukraine. Mitig Adapt Strateg Glob Change 24, 985–1006 (2019). https://doi.org/10.1007/s11027-018-9795-y
Here are some comments and remarks:
Lines 1-2 - Authors could improve the title of the article. The article does not contain enough information about the perspective of carbon neutralization.
L. 15-34 - The authors must improve the abstract, including the first sentences. For example, there would be more logical to say about the carbon cycle and following about the carbon budget. And so on.
L. 35 - Please, add more keywords. Remember that keywords must not contain the words as in the title.
L. 41 - Add space to "China(Fang et al., 2018)". And in other cases.
L. 67, Figure 1. - The diagram looks very simple. Why do you not show photosynthesis in the diagram?
L. 78, 80 - Add space and check the whole text.
L. 78 - Could you add data about forest loss and gain in Southwest China?
L. 96-97 - Did authors hear about semi-empirical methods?
L. 119 - Figure 2, not 1. Why do authors use many factors (temperature, water, soil and others) in Figure 2 as inputs? How are they connected with assessment NPP by remote sensing?
L. 127 - Check the reference to Fang.
L. 272 - Please, check the units of measurement in the whole text. There are many mistakes in measurement units (dots, top index etc.).
L. 379-383 - Is it the author's data or other researchers?
L. 530 - It is conclusions?
Author Response
Thank you very much for your time and constructive comments. We revised/improved th manuscript carefully according to your comments/suggestions point-by-point.
Please see the attachment.
Author Response File: Author Response.docx
Round 2
Reviewer 1 Report
Authors introduced relevant revisions and paper looks alright now
Reviewer 2 Report
Dear authors,
thank you for your time and efforts in improving the article and answering my questions.
One remark:
Could you use gC•m–2•a–1 within the whole text of the article?
I am sure this research will be interesting for readers.
