Fig. 1.

Temporal trends in N fertilizer, permanent meadows and pastures, and permanent crop lands. (a) Temporal trends in the annual amount and consumption of N fertilizer for most nations around the world (globe) and for China during 1961–2013, indicating that global N deposition has increased in the past decades. (b) Temporal trends in the land area of permanent meadows and pastures or crops globally and for mainland China during 1961–2012. Solid and dashed lines correspond to the data at global scale and China national scale, respectively. Data in (a) and (b) were obtained from the International Fertilizer Industry Association (2015) and the FAOSTAT (2014), respectively.