Dear Dr. Le Gland:

Thank you for submitting this paper to Biogeosciences. It addresses an important topic of interest to a wide audience and it has been well received by the referees. Referee # 1, Dr. Santos, is very enthusiastic about your manuscript and recommend publication pending very minor technical corrections. Referee # 2 also recommend eventual publication but identified a few points that require attention. Your rebuttal to referee #2 gives me the impression that you can easily resolve the issues identified and I therefore invite you to submit a revised version, which after inspection by me, will be likely be acceptable for publication in Biogeosciences.
Note: could you still upload a reply to referee # 1 (Dr. Santos).

With best regards, Jack Middelburg, Associate Editor

Dear Dr. Le Gland:

I have read your rebuttal and revised version and I am happy to inform you that your paper is now accepted for publication. While reading I identified a few minor issues that might need correction.
- Line 1, isotope in the ocean
- Line 9: …Ocean is presented/provided but not assessed.
- Line 16: replace diffusion with diffusive release from sediments
- Line 34: …from rivers, release from sediments by diffusion and bioturbation, and dividing…
- Page 5, line 6 (note line number are now per page): at larger depths not higher depths

Thank you for submitting this thorough, well-designed study to Biogeosciences.

With best regards, Jack Middelburg, Associate Editor