Dear Authors,

Thank you for providing detailed responses to the comments and suggestions offered by two reviewers.

The two reviewers recognized the novelty of your approach combining mineral-associated organic matter characterization with 13C‐NMR and 14C dating. However, they provided many critical comments, above all on your interpretations of the key findings and English writing. In my view, the manuscript would require a substantial revision to address a number of raised issues. Therefore, I have to recommend ‘reconsider after major revisions’.

I would like to ask you to make all the changes easily identifiable in a marked-up manuscript based on your point-by-point responses to the reviewers' comments. If possible, please specify the line numbers of the revised parts in your responses accompanying the revised manuscript.

Sincerely,

Ji-Hyung Park
Associate Editor, Biogeosciences

Dear Authors,

Thank you for your careful revision of the manuscript incorporating all the reviewer comments and suggestions.

I am pleased to let you know that your manuscript can be published after a final “minor” revision of the following points :

- Abstract: Please combine separate sentences into one paragraph. Though you could separate the long introduction and methods from the results and discussion, the multiple-paragraph format is unusual. I also thought you could reduce some redundant, long sentences, as illustrated below. In the current version, the length reduces the appeal of your hard work.
- Line 19 “the midlatitudes”: Please indicate that your samples are only from Europe, not from other midlatitudes.
- Lines 21-21: To reduce the very long abstract and make your points clearer, I would recommend combining these sentences, like “We expected that NaF/NaOH would extract less, younger MOC…, particularly in subsoils and soils with high contents of pedogenic oxides.”
- Lines 38-41: …the Δ14C values of oxidized OC (-50±110‰) were similar to those of OC extracted with NaF/NaOH (-51±122‰), but oxidation residues (-345±227‰) were much more 14C-depleted than in the residues of NaF/NaOH extraction (-130±121‰).
- Lines 41-42: Please rewrite the weird expression “leaving increasingly older residues behind the more OC is removed”.
- Lines 45-47: Readers would also expect your conclusion on the employed methodological approaches (“fractionation schemes”). You wanted to “test if maximum desorption with NaF/NaOH is a suitable indicator for the labile proportion of MOC” (line 124). Please add if you have any conclusion or recommendation regarding the extraction methods.
- Line 56 “oxi-hydroxides” or oxyhydroxides (?): Did you intend to use this term to cover all oxides, oxyhydroxides, and hydroxides? Please clarify or define this.
- Line 126 “across Europe”: across central Europe?
- Fig. 1 and Table 1: It seems inappropriate to show these published results here in the Methods section. If you want to provide extra information from the cited paper, you could move these to Supplementary Information (or to Results if you can report something new).
- Lines 135-139: Please indicate the soil classification system you followed. Is it the World Reference Base?
- Line 398: “differing” or different?
- Line 403: The unique MOC composition in the podzol-type soil “is”
- Line 405 “dissolved organic carbon”: double check if DOC has been defined at its first use and consistently used throughout the manuscript.
- Lines 526-527: Please briefly describe how your alternative hypotheses differ from the original outcomes listed in Fig. 10.
- Figs. 7-8: It would be more “reader-friendly” if you indicate major spectral regions on top of the spectra.
- Fig. 10 caption: hypotheses explaining “variations in” Δ14C values of MOC across sites and with depth

Sincerely,

Ji-Hyung Park
Associate Editor, Biogeosciences