China has to grow food to feed >20% of the world’s population with only 9% of the world’s arable land. Consequently, food security remains the top priority above other concerns unlike the case in developed economies, where national-scale food security is not a major concern (32). This is the basis for scenario 3, where we consider maintaining N fertilizer use at the 2010 level without further increases. This means putting an end to the 50-y trend of increased N production and use. This is not to be taken lightly, because to many, decision makers and farmers alike, continuous growth in agricultural output is thought to depend on increasing fertilizer input. Although still undesirable environmentally, this scenario is probably more likely than scenarios with fertilizer use reductions, given China’s political and societal modes.