Both reviewers acknowledge that this manuscript presents valuable contributions to peatland modeling and addresses highly relevant topics—specifically the implementation of a Sphagnum plant functional type (PFT) in the ISBA land surface model and the investigation of drought impacts on peatland carbon dynamics over a 70-year period (1959–2022). However, both reviewers raise concerns about the scope and depth of the analyses, the validation approach, and the presentation. Based on the reviews and author responses, I recommend major revisions. The manuscript has the potential to make important contributions to peatland modeling, but the analyses must be deepened, the validation approach more critically assessed, and the presentation substantially improved before it can be accepted for publication.

We acknowledge that the main technical comments have been addressed. It remains uncertain whether the study’s novelty is strong and whether the conclusions are robust, given limitations in the validation data and modest improvements in model performance when adding the Sphagnum plant functional type. Especially the low correlations between modeled and statistically derived CO2 fluxes that could also reflect uncertainties in the herbaceous parameterization, given the relatively low Sphagnum cover at the site. However, the study is publishable because the authors clearly articulate these limitations, do not oversell the results, and maintain good alignment between aims, methods, and conclusions.

In light of this, although the quantitative performance gains remain modest and subject to data and parameter uncertainties, the explicit treatment of Sphagnum in ISBA at this well-characterized site, together with the transparent discussion of limitations, provides a sufficiently useful contribution to justify publication. I therefore ask for a minor revision, encouraging the authors to retain and, where possible, further sharpen their cautious wording around model performance, uncertainty, and the generality of their conclusions.

Thank you for your contribution.