Appropriate Removal of Forest Litter is Beneficial to Pinus tabuliformis Carr. Regeneration in a Pine and Oak Mixed Forest in the Qinling Mountains, China
Round 1
Reviewer 1 Report
The topic of the paper is quite interesting, deals with ecological invasions which is an important ecosystem disturbance under climate change.
I also like the fact that the study combines field studies which helps to reinforce the laboratory experiments.
The methodology using activated carbon seems controversial (https://www.sciencedirect.com/science/article/pii/S1439179109000024) although there is a quite number os studies using it. The paper seems to address this topic reasonably well.
The results are sound and the experiment seems well conducted. Although I think the statistical significance between the treatments should be revised. The Standard errors/deviation are not clearly shown or the number of samples used. This makes me somewhat uncomfortable as I do not completely trust the results.
Also the impacts of the different concentrations on seed germination, root and biomass are not consistent. There is a very high variability in the impacts which makes me wonder if allellochamicals do play a role. It may be only a matter of data representation (for example the RI may not be the best to express the differences). However, some trends do exist.
Also the fresh weight should not be used... never. When dealing with plants growth, the biomass is ALWAYS reported on a dry weight basis. Is it possible to change it? It would be much better.
The authors should improve the results session. Start with showing the major results and then, if something is interesting, focus on that topic. The authors approach is to write all the results in short sentences and the text becomes extremely confusing to read.
I suggest a native English speaker review.
For the reasons mentioned above (and also the 121 comments on the PDF), I recommend the manuscript for publication but after a major revisions.
Author Response
Reviewer 2 Report
The paper by Huo and co-workers reports an allelopathy study of the influence of forest litter in the regeneration in a pine and oak mixed forest. It is an interesting study but the manuscript must be reviewed in depth.
Line 65: repeat twice “in south China”.
Lines 173-175: The effect of activated carbon is not clear. In three of the eight samples tested, the inhibition is greater than in the control, almost 30%, this behavior must be explained in the text.
In general, the effect of activated carbon should be to eliminate the organic matter from the aqueous extract, and therefore, decrease the inhibition or stimulation of growth, since the metabolites responsible for the activity are in a lower concentration. Throughout the results there are many cases in which this does not happen and no explanation is given. For example, the effect on root length with oak soil in P. tabuliformis.
Line 217-225: In fresh weight, it is not explained that at a high concentration there is no appreciable effect, however this effect is almost 10 times higher at low concentrations (for example, pine litter in P. armandii)
Line 257-265: further explanation is needed on the identification method used by HPLC-MS. If you have worked in full scan in MS, are the metabolites identified as the majority? How have they been identified, by comparison with standards?
The bibliography must be extensively reviewed and unified according to the criteria of the journal. For example, species names must be italicized (3, 5, 22, 26, 27, etc.). The name of the journal should be italicized and abbreviated (24, 25, 27, 35, 39, etc.). There is some whole title in capital letters (37), or with all the words in capital letters (42, 47, 49, etc.).
Author Response
Please see the attachment.
Author Response File: 
Author Response.doc
Reviewer 3 Report
The manuscript is written in good style. It surely fits into Journal’s aims and scope, and I think it is interesting enough to be published after a revision.
Specific comments: Abstract should be completely changed and should fit into the Journal's guidelines. All figures are illegible in the text. The appendix is ok. Please make sure that the figures will be readable after printing. There are more figures in the text than in the attachment.
Author Response
Please see the attachment.
Author Response File: Author Response.doc
Round 2
Reviewer 1 Report
The results are significantly better with the change in the graphs. It is now much more comprehensive.
However the manuscript still needs an English revision. Especially in the Introduction session. I tried to improve the text a bit in the pdf version (which is always very difficult), but seems that the authors did not look to the version uploaded in the platform, unfortunately.
I recommend for publication but only after a revision by someone that can track technical terminology. In some cases it is unreadable.
Author Response
Please see the attachment.
Reviewer 2 Report
The explanations of the authors are correct
Author Response
Please see the attachment.
Author Response File: Author Response.docx
