Fig. 1: Surface mass concentrations of particulate organic nitrogen (PON) in the tropical South Pacific in March 2015.
From: Long term decline of the planktonic biomass in a hotspot of nitrogen fixation
Average 1-month (March 2015) composite images of (a) algorithm-derived PON concentrations (mg m-3) in surface waters of the tropical South Pacific. The black solid and dashed boxes refer to the Melanesian archipelago and the South Pacific Gyre areas, respectively. The red box corresponds to the region defined as N2 fixation hotspot16. b Station-by-station comparison between the algorithm-derived PON concentrations (mg m-3) (blue squares) and the surface in situ PON concentrations measured in the mixed layer during the OUTPACE cruise (green circles). Shaded regions show standard deviation around the satellite mean derived PON concentrations. Error bars show standard deviation around the in situ PON concentrations.
