Northeast China, the important grain‐producing region in China, is under threat from soil degradation because of long‐term conventional tillage (CT). The adoption of conservation tillage is anticipated to restore soil fertility, maintain crop yields and enhance sustainability. However, the integrated effects of conservation tillage practice on crop yields and soil organic carbon (SOC) remain unclear. In this meta‐analysis of peer‐reviewed studies conducted in the Northeast China region, we assess crop yields and SOC values under no‐till, ridge tillage and subsoiling tillage practices. The results indicate that in areas with mean annual temperatures (MAT) below 3°C, crop yields were significantly (p < .05) higher under ridge tillage (0.8%) and subsoiling tillage (13.1%) compared with CT, whereas yields reduced under no‐till (−3.7%). Ridge tillage generally had a similar effect on crop yield as no‐till, without the negative impact in colder regions. We also report that no‐till practice increased SOC concentrations by 24.1%, 43.9% and 17.4% in areas of higher temperature (MAT > 6°C), low mean annual precipitation (MAP) (<500 mm) and continuous cropping conditions, respectively. Ridge tillage and subsoiling tillage also had positive effects on SOC concentrations (to a lesser degree than no‐till), indicating that conservation tillage can enhance SOC in Northeast China. Overall, the implementation of different conservation tillage measures in Northeast China was found to enhance crop yields and sequester carbon. We recommend that ridge tillage is used in colder areas and that subsoiling tillage is used in rotation with other tillage measures to maintain crop yields.

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Northeast China(NEC) is the main grain-producing area in China, but soil degradation is severe due to the long-term use of conventional tillage(CT). It is necessary to restore soil fertility, maintain crop yield, and enhance sustainability using conservation tillage in NEC. However, the integrated effects of conservation tillage on crop yield and SOC under different conditions in NEC are still unclear. Using 70 peer-reviewed papers, we assessed the crop yield and SOC sequestration effect, and their relationship under no-till(NT), ridge tillage(RT), and subsoiling tillage(ST) in NEC. The results indicated that in areas with a mean annual temperature (MAT) < 3℃, yield under NT was significantly lower than CT by 3.7% whereas RT and ST were higher than CT by 0.8% and 13.1% (P<0.05). RT generally had a similar effect on yield as NT, but RT did not have a negative impact on yield in colder regions, indicating that this may be a more suitable conservation tillage practice in these areas. ST may be used in rotation with other tillage measures to maintain crop yield if necessary. NT could increase SOC concentration by 24.1%, 43.9%, and 17.4% under high MAT (>6℃), low mean annual precipitation (MAP) (<500mm), and continuous cropping, respectively. The mean SOC sequestration rate under NT, RT, and ST was 0.953, 0.099, and 0.101 Mg C ha-1 yr-1, respectively. Overall, the implementation of different conservation tillage measures in NEC can enhance crop yield as well as carbon sequestration, indicating its potential to be popularized in NEC.