“…Several studies have calibrated and validated microbial decomposition models (Robertson et al, ; Wieder et al, , ) using globally gridded soil databases such as the Harmonized Word Soils Database (HWSD, FAO/IIASA/ISRIC/ISSCAS/JRC, ) and the Northern Circumpolar Soil Carbon Database (NCSDC, Tarnocai et al, ). However, these global databases do not contain uncertainty estimates (Dai et al, ), and previous studies have identified significant differences between SOC estimates from these databases or between grid‐scale estimates from these databases and point‐scale in situ observations (Tifafi, Guenet, & Hatté, ; Figure S1). In addition, there is still no reliable globally gridded database of plant litter input.…”