Fig. 2: Temporal variability of surface mass concentrations of particulate organic nitrogen (PON).
From: Long term decline of the planktonic biomass in a hotspot of nitrogen fixation
a Temporal variations of monthly PON concentrations (mg m-3) in surface waters as indicated with blue and grey colors corresponding to the Melanesian archipelago (station 9 on Fig. 1a), South Pacific Gyre (station 15 on Fig. 1a) datasets, respectively. b Temporal variations of monthly PON concentrations in surface waters of the Station ALOHA (black triangle on Extended data Fig. 4). Shaded regions show standard deviation around the mean. The green circles refer to the surface in situ PON concentrations measured at the Station ALOHA. c Contribution of the seasonal, and (d) trend components to the total variance of PON in the Melanesian archipelago region (black solid box on Fig. 1a) as calculated with the Census X-11 method applied on the monthly time series between December 2002 and December 2022.
