Dear Drs. Zhang and Zou,

Thank you for submitting your manuscript “Ammonium and nitrate additions differentially affect soil microbial biomass of different communities and enzyme activities in slash pine plantation in subtropical China” to Biogeosciences. Two expert reviewers and I have assessed your submission and feel that it has potential for publication as it addresses important questions on the effect of atmospheric nitrogen deposition on forest ecosystems, and applies novel approaches by differentiating the types of N deposited. However, the reviewers also identified numerous ways to improve the manuscript.

At this stage of the review process, I am providing the post-discussion editor decision which would normally be followed by revision. However, you have already revised your paper according to the reviewers’ comments which puts you ahead of this step. I have evaluated your revised manuscript and provided additional comments to be addressed below.

At this point, I ask that you please revise your paper based on my comments and resubmit for further review. In addition, please submit a version of your paper so all changes marked as track changes.
Please feel free to contact me with any questions.

Sincerely,
Dr. Denise M. Akob

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Associate Editor’s Comments

Abstract: there is no mention of slash pine plantation but it is part of the title. Please revise to include and to link your results back to the habitat or if the habitat is not the key part of the story then revise the title.
L. 33: change to hydrolysis. The correct term is hydrolysis and cannot be plural
L. 50: change to “is mostly comprised of”
L. 69: define the BG and NAG acronyms
L. 106: “in line with the economic theory” does not fit here. No economic theory has been presented. I would omit it and start with “Microorganisms…” or try to introduce this better
L. 114-116: add a reference
L. 134: change to “C-“
L. 135: change to “;”
L. 142: there are so many acronyms in the paper that I would not abbreviate the experimental station, just write it out.
L. 149: define a.s.l.
L. 153-165: this is still not clear. How many test plots were there, first you say one control and one test then you state there are 9? Start with how they were divided up then discuss the treatments. On l. 157, it reads as if you added both NH4 and NO3 to both test plots. So, how were you comparing effects of each N source? It might be useful to add a schematic to supplemental information. For the application, how much time was there between sprayings? It was only 1 day per month when N was applied?
L. 174: I would not use synthetic here. I suggest changing to seasonal.
L. 183-189: was the soil:water shaken before measurement of pH and N? In this section, either provide details on the methods or provide references.
L. 187: soil cannot be extracted with soil, revise
L. 205: what concentration of sodium acetate?
L. 241: specify panel A, e.g., Fig 1A
L. 241-242: incorrect usage of “respectively”. Please always refer to the specific figure panels you are referencing.
L. 258: you are missing an “and”
L. 264: I caution against using the term “shifted” when you are not showing or referring to time series data.
L. 273-283, Table 2 and elsewhere: are the enzymes supposed to be named with Greek letters? The naming is inconsistent with the intro and methods. Please verify and correct throughout the paper.
L. 292-294: this sentence is strangely worded—it is unclear what you are referring to with use of respectively twice in this sentence. What are the values respective of?
L. 292-303: refer to your table and figure earlier in the paragraph
L. 312-313: C cannot be included in the sum of ammonium and nitrate, remove the parenthetical statement
L. 350: only include the reference once.
L. 356-357: do you mean microbial communities? Microorganism systems is an unsual choice.
L. 560: Bacteria is spelled wrong
L. 558: soil dissolved organic carbon is misspelled
Fig. 4f: the “Cb” is not easy to read
Fig. 6: please define the abbreviations in the legend.

Dear Drs. Zhang and Zou,

Thank you for revising your manuscript for Biogeosciences. Two expert reviewers and I have assessed your revised submission and feel that it is appropriate for publication as it addresses important questions on the effect of atmospheric nitrogen deposition on forest ecosystems, and applies novel approaches by differentiating the types of N deposited.

I am selecting publish subject to technical corrections as Figure S2 is of poor quality. Please revising and upload a better version for final publication.

Please feel free to contact me with any questions.

Sincerely,
Dr. Denise M. Akob