Abstract: 【Objective】Paddy fields are one of the important sources of greenhouse gas emissions, farming practices and water management can reduce greenhouse gas emissions from field to a certain extent. Ridge cultivation and direct-seeding is a new kind of rice planting pattern that saves costs and increases economic efficiency, However, there are few studies on the comprehensive effects of water management on greenhouse gases and rice yield under ridge cultivation and direct-seeding. Exploring the impact of water management of ridge cultivation and control irrigation on grain yield and greenhouse gas emissions is of great significance for increasing grain yield and reducing greenhouse gas emissions. Exploring the effects of control irrigation on grain yield and greenhouse gas emissions in ridge cultivation direct-seeding paddy field can provide theoretical basis and technical approaches for the innovation of high-yield and emission-reduction. 【Method】In this study, a rice-radish rotation system under the ridge cultivation from 2019 to 2021 was conducted to use as the research object. By setting up traditional flooded furrow irrigation (TFI: the moisture is about 5 cm above the ridge), controlled furrow irrigation 1 (CFI1: moisture is about 5 cm below the ridge), controlled furrow irrigation 2 (CFI2: the moisture is about 10 cm below the ridge), and control furrow irrigation 3 (CFI3: the moisture is about 15 cm below the ridge) four treatments. The research includes studying the greenhouse gas emissions and global warming potential(GWP) of rice-radish season by airtight static box-gas chromatography, measuring the rice yield, soil reducing substances, ammonium nitrogen and nitrate nitrogen, identifying optimal irrigation patterns that both reducing the GWP and increasing the rice yield.【Results】Based on the three-year experimental results, compared with TFI treatment, controlled irrigation can significantly reduce the cumulative emission of CH₄ by 22.81%-78.47% in the rice season, of which CFI3 has the most significant effect; CFI2 treatment significantly increases the cumulative emission of N₂O by 20.45%-59.90% , CFI3 significantly reduced the cumulative N₂O emissions by 12.08%-41.41%, and CFI1 had no significant effect on the cumulative N₂O emissions. For radish season, compared with TFI controlled irrigation can significantly reduce the cumulative emission of CH₄ by 34.87%-53.31%, among which CFI2 and CFI3 have the most significant effects; CFI1, CFI2 and CFI3 treatments can significantly increase the cumulative emission of N₂O by 35.00%-120.00%. The results of two-way ANOVA showed that control irrigation, the interaction of control irrigation and year had a extremely significance on the cumulative emission of CH₄ (P<0.01). The control irrigation, year, the interaction of control irrigation and year had a extremely significance on cumulative N₂O emissions (P<0.01). Compared with TFI, controlled irrigation treatment can significantly reduce GWP by 20.24%-74.87% in rice season; CFI1 and CFI2 treatments increases rice yield by 12.34%-33.97%, CFI3 treatment has no significant effect on yield. Controlling irrigation reduced GHGI by 29.37%-75.92%. Controlled irrigation  affects CH₄ emissions by reducing the total amount of reducing substances, active reducing substances and reducing Fe²⁺ by 15.00%-30.84%, 53.45%-71.65% and 60.47%, respectively. It also affects N₂O emissions by reducing NH₄⁺ by 7.51%-9.87% and increasing NO₃^- by 5.81%-8.55%.【Conclusion】Controlled irrigation affects GHG emissions through soil properties such as NO₃^-, NH₄⁺, and reducing substances. Therefore, CFI1 and CFI2 have the best effects in terms of reducing GWP and increasing rice yield. Under the conditions of ridge cultivation and direct-seeding in paddy field, the depth of irrigation is two-thirds or half of the depth of traditional furrow irrigation flooding is the best water management method to alleviate greenhouse gas emissions and increase rice production.

Key words: ridge cultivation, direct-seeding, water management, greenhouse gas, rice yield, radish