CN-N: A gridded dataset of nitrogen rate for rice, wheat and maize in China developed using the county-level nitrogen statistics

Abstract

Existing agricultural nitrogen datasets in China are mostly developed using coarse national or provincial statistics. A crop-specific nitrogen rate dataset based on the finest-scale agricultural nitrogen statistics at the county level remains lacking. Here, we constructed a new dataset (CN-N), which provides annual nitrogen rates for rice, wheat and maize in China at a 1-km spatial resolution from 2004 to 2016. This dataset was developed by harmonizing county-level and provincial agricultural nitrogen statistics with gridded crop distribution maps, resulting in 13 years of nitrogen rate maps for each crop covering 2004–2016. Validation against farmers' surveys by crop indicates CN-N reliably quantifies average nitrogen rates and trends for each crop over 2004–2016, demonstrating improved spatial heterogeneity compared to previous datasets rasterized using only provincial statistics. Our study provides a crop-specific, temporally consistent, gridded nitrogen rate dataset based on the finest-scale county-level agricultural nitrogen statistics. This can support future process-based modelling for sustainable agricultural nitrogen management strategies.