Fig. 4: Significance and contribution of NH4+-derived pathways to riverine hyporheic N2O production at the global (a), regional (b), and temporal (c) scales and statistical analysis of rates and contributions (d).
From: Ammonium-derived nitrous oxide is a global source in streams
a–c The locations of the pie charts show the sampling sites; the sites for temporal-scale analysis are marked with solid orange circles. Detailed information on the sampling sites can be found in Supplementary Data S1. For each sampling site, the pie chart shows the total N2O production rate. The pie chart colors represent the relative contributions of the NH4+-derived (blue) and NO3−-derived (yellow) pathways to total N2O production. d Box charts (the horizontal line indicates the median, the box indicates the 25th and 75th percentiles, the whisker shows the range from the 5th to 95th percentiles, and the colors show the N2O production pathways) indicating the potential rate of N2O production via NH4+-derived and NO3--derived pathways and their related contributions in riverine hyporheic zones worldwide (n = 41 independent experiments).
