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The objective of this study was to quantify soil methane (CH4) and nitrous oxide (N2O) emissions when converting from minimum and no-tillage systems to subsoiling in the North China Plain.The relationship between CH4 and N2O and soil temperature,moisture,NH4+-N,organic carbon and pH were investigated.Soil absorption of CH4 appeared to increase after converting from no tillage to subsoiling (NTS),from harrow tillage to subsoiling (HTS) and from rotary tillage to subsoiling (RTS).Meanwhile,N2O emissions also increased when the converting happened.After converting to subsoiling,the combined global warming potential (GWP) of CH4 and N2O increased by approximately 0.05 kg CO2 ha-1 for NTS,0.02 kg CO2 ha-1 for HTS and 0.23 kg CO2 ha-1 for RTS,respectively.Soil organic carbon,temperature,moisture,NH 4+-N and pH also changed after converting to subsoiling,which were correlated with CH4 uptake and N2O emissions.However,there was no significant correlation between N2O emissions and soil temperature in this study.Grain yields of wheat were improved after converting to subsoiling.Under HTS,RTS and NTS,the average grain yield elevated approximately 1695.38 kg·ha-1,2416.25 kg·ha-1 and 2804.33 kg.ha-1,respectively.Our findings indicated that RTS and HTS would be ideal rotation tillage systems to balance the GWP decreasing and grain yield improvement in the North China Plain region.