Interconnection between carbon (C) and nitrogen (N) cycles in the soil has been recognized for a long time, however only a few C cycle models within climate models consider this interplay. Here, the results from the ROMUL model that directly describe coupling between soil C and soil N and is incorporated in a climate model with a C cycle INMCM are demonstrated. First, the steady-state carbon amount in a mineral soil humus pool as a function of C/N ratio in litter and mean annual temperature was analyzed. As for the future projections for the 21st-22nd centuries, the model predicts C uptake in the global soil pool due to higher litter input caused by carbon dioxide fertilization effect, but some grid cells act as C source or are C neutral. Nitrogen dependency of additional accumulation of C in the mineral soil humus pool in is seen only for the higher percentiles (grid cells that accumulated most C).

Ключевые слова: carbon and nitrogen cycles, soil processes, carbon dioxide fertilization, climate, modeling, climate projection