Land–water–energy nexus in agricultural management for greenhouse gas mitigation

•A land–water–energy nexus framework based on agricultural GHG emission is proposed.•Rice fields produced 29% of total crop protein while emitted 54% of total crop GHG.•Structural adjustment by converting paddy fields to drylands reduces GHG by 18.8%•Technical improvement by increasing resource use efficiency reduces GHG by 23.9%