Precipitation amount, seasonality and frequency regulate carbon cycling of a semi-arid grassland ecosystem in Inner Mongolia, China: A modeling analysis

► Precipitation response of C fluxes in a grassland ecosystem was investigated. ► The response of NPP to 10-30% increase/decrease in precipitation is non-linear. ► A shift of 10-30% of precipitation from other seasons to spring enhance annual NPP. ► A shift of 10-30% of precipitation from other seasons to autumn decrease annual NPP. ► The number of precipitation days significantly influence NPP and NEP.