Estimation of greenhouse gases emission factors of China's nitrogen, phosphate and potash fertilizers

As fossil fuel based chemical products, synthetic fertilizers are highly energy鄄intensive and therefore highly carbon鄄intensive products as well. Fertilizers are one of the most important modern agricultural materials for enhancing crop yields. The manufacture of fertilizers is also a considerable indirect greenhouse gases (GHGs) emission source related to agricultural activities. To feed its huge population, China has raised its average fertilizer application level from 86.7 kg / hm in 1980 to 346.1 kg / hm in 2010 (total N, P 2O5 and K2O). China has been the largest fertilizer producer and consumer worldwide for ten years, and its fertilizer consumption has exceeded 4.76 伊10 t, almost one third of the world忆s total, since 2005. Thus, it is essential to evaluate the GHGs emission related to the production and consumption of synthetic fertilizers in China. However, most current Life鄄Cycle Analysis (LCA) studies on China忆s agricultural GHGs emission use foreign fertilizer emission factors ( GHGs per unit of fertilizer product) because the actual domestic factors were not available, which might result in significant miscalculations and uncertainties. To solve this problem, we collected data specific to China忆s fertilizer manufacture and consumption, and then estimated GHGs emission factors for several types of nitrogen,