Revision Notes "Eq. 4. I recommend to replace k with j. K could result in misunderstanding (it could be mixed up with a rate constant)" We totally agree with this comment of the reviewer. Therefore, it has been changed. L. 371-372 of the new version. Please present in a new table the mean temperature and rainfall for each sub-climate regions used in the study. We acknowledge the comment of the reviewer. We decided to not to include a table with values of temperature and precipitations due to the high complexity of the Köppen-Geiger climate classification. As it is shown in the figures below (Kottek et al., 2006), each climate is defined by three letters. Second letter corresponds to precipitations and the third one to the air temperature conditions. We considered that include all this information in a table would not be so much helpful to the paper and, for that reason we decided to include only the full name of each climate (e.g. Csa (Warm temperate, dry summer, hot summer)) and referring the table to this paper of Kottek et al., 2006. Highlights  Effects of RMPs on SOC in woody crops were assessed using literature data  Average SOC sequestration rate for all RMPs was 3.8 t C ha-1 yr-1.  C sequestration rates in olive orchard ranged 1.1 (CC) to 5.3 (OA) t C ha-1 yr-1.  C sequestration rate in vineyards was 0.78 t C ha-1 yr-1 in CC management.  C sequestration rates were highest during the first years of the RMPs *Highlights (for review)

Biogeochemical simulation models are important tools for describing and quantifying the contribution of agricultural systems to C sequestration and GHG source/sink status. The abundance of simulation tools developed over recent decades, however, creates a difficulty because predictions from different models show large variability. Discrepancies between the conclusions of different modelling studies are often ascribed to differences in the physical and biogeochemical processes incorporated in equations of C and N cycles and their interactions. Here we review the literature to determine the state-of-the-art in modelling agricultural (crop and grassland) systems. In order to carry out this study, we selected the range of biogeochemical models used by the CN-MIP consortium of FACCE-JPI (http://www.faccejpi.com): APSIM, CERES-EGC, DayCent, DNDC, DSSAT, EPIC, PaSim, RothC and STICS. In our analysis, these models were assessed for the quality and comprehensiveness of underlying processes related to pedo-climatic conditions and management practices, but also with respect to time and space of application, and for their accuracy in multiple contexts. Overall, it emerged that there is a possible impact of ill-defined pedo-climatic conditions in the unsatisfactory performance of the models (46.2%), followed by limitations in the algorithms simulating the effects of management practices (33.1%). The multiplicity of scales in both time and space is a fundamental feature, which explains the remaining weaknesses (i.e. 20.7%). Innovative aspects have been identified for future development of C and N models. They include the explicit representation of soil microbial biomass to drive soil organic matter turnover, the effect of N shortage on SOM decomposition, the improvements related to the production and consumption of gases and an adequate simulations of gas transport in soil. On these bases, the assessment of trends and gaps in the modelling approaches currently employed to represent biogeochemical cycles in crop and grassland systems appears an essential step for future research.

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