A hierarchical framework for unpacking the nitrogen challenge - Li, Tingyu; Zhang, Xin; Zhong, Yuxiu; Davidson, Eric A; Dou, Zhengxia; Zhang, Weifeng; Pavinato, Paulo Sérgio; Martinelli, Luiz Antonio; Kanter, David R; Liu, Jianguo; Zhang, Fusuo (Earth's Future, 2022)