Table 3.

Surface N₂ fixation rates and dominant diazotroph (s) of different Oceanic Region. ARA = acetylene reduction assay.

Location	Surface N2 fixation rate (nmol N L−1d−1)	Method	Dominant Diazotroph (s)	Reference
nSCS and ECS Kuroshio	1.14–10.40	ARA	Unicellular diazotrophs	This study
nSCS coastal upwelling	0.1–5.6	15N2 gas bubble	Unknow	28
SCS (Mekong River plume)	0.59–22.77	15N2 gas bubble	Trichodesmium spp. and DDAs	63
Western North Pacific	≈0.3–22	ARA	Unicellular diazotrophs	64
North Pacific	0.360–3.05	15N2 gas bubble	Heterotrophic bacteria	65
Northeast Atlantic	<0.4	ARA	Unicellular diazotrophs	66
Eastern North Atlantic	0–151.2	15N2 gas bubble	Trichodesmium and UCYN-A	67
Arabian Sea	0.8–225	15N2 gas dissolution	Trichodesmium bloom	68
Indian Ocean	0.18–1.27	15N2 gas bubble	Heterotrophic bacteria	69