Elevated atmospheric CO2 and warming enhance the acquisition of soil-derived nitrogen rather than urea fertilizer by rice cultivars

•Co-elevated CO2 and temperature increased plant N uptake and yield of the rice cultivars.•The increase of rice N under climate change was mainly derived from soil-N rather than urea fertilizer.•Urea fertilizer supply further enhanced the uptake of soil-derived N under climate change.•Climate change may accelerate the N mineralization in paddy soils and fertilizer N loss.