Dryland high-quality rice cultivation significantly reduces greenhouse gas emissions and enhances soil multifunctionality

Based on the above, this study used the DHR variety Dianheyou 918 as the research object and established a comparative experiment between dryland rice (DR) and flooded rice (FR) cultivation. Static chamber-gas chromatography was employed to monitor the dynamics of CO2, CH4, and N2O emissions. Combined with high-throughput sequencing, widely targeted metabolomics, and quantitative real-time PCR (qPCR) techniques, we systematically analyzed soil microbial community structure, differential metabolite compositions, and the expression characteristics of functional genes involved in carbon, nitrogen, and sulfur cycling. Coupling with soil physicochemical properties and multifunctionality indices, this study aims to explore the GHG mitigation effects and soil multifunctionality enhancement mechanisms of DHR cultivation. Two hypotheses are proposed: (1) The DR cultivation mode can significantly reduce the emissions of CO2, CH4, N2O, and global warming potential (GWP) in paddy fields; (2) Dryland conditions drive GHG mitigation and soil multifunctionality enhancement by reshaping soil microbial communities (improving stability and complexity), regulating metabolite compositions, and modulating functional gene expression. This study seeks to provide a scientific basis for clarifying the ecological and environmental benefits of DR and revealing the microbe-metabolite regulatory mechanisms underlying paddy GHG mitigation, thereby supporting the development of carbon-neutral pathways in rice production.