and NO3− leaching. We summarized 397 published field measurements (138 paddy fields and 259 upland fields) from 47 literature sources. We used IPCC (37) values for the proportion of those losses emitted as N2O (Table S8). Then, we calculated the GHG emission factors for paddy fields and upland fields, respectively (Table S3).
Total GHG Emissions from N Fertilizer Production and Utilization.