Balancing N inputs for China’s green agricultural development

 

Using environmental threshold and meta-analyses, we identified ‘ideal’ N inputs for China. Nitrogen inputs required to achieve food security for China increased from 12 to 30 Tg N yr-1 during 1950 and 2015, while actual N inputs increased from 6 to 52 Tg N yr-1 during the same period, exceeding the required and critical inputs (28-35 Tg N yr-1 ) after 1980. We show how 20 Tg N yr-1 reduction in N input can be achieved through integrated N management practices. Such a ‘win-win’ would improve environmental quality greatly but need systematic reforms on agricultural structure, technology-transfer mode, and environmental policies.

Nitrogen (N) fertilizer has played a key role in feeding the increased global population since the invention of the HaberBosch process (Erisman et al., 2008). With the increasing population and living standards, China is facing a huge challenge on how to produce enough food to meet the future demand only using environmental-safe N input. This challenge needs urgent answer for green agricultural development, that is, meeting double targets of food security and environmental sustainability