Here, we quan titatively evaluate GHG emissions for China’sN
fertilizer chain through a life cycle analysis beginning from fossil
fuel mining as the industry’s energy source to postapplication of
fertilizers in thefield. To do these analyses, we used survey data
of 230 fertilizer plants (Table S2) and synthesized literature data
of 853field measurements (Table S3), from which emission factors
were derived. We then calculated annual GHG emissions from
1980 to 2010 using statistical data from the China Nitrogen Fertilizer Industry Association (Fig. S1) and estimated future emissions in 2020 and 2030 assuming a 1% annual increment (the same
as in the past decade) in N fertilizer demand