Fig. 3: Predicted global organic carbon biomass in planktonic Rhizaria, their impact on carbon flux attenuation, and their carbon demand.

a, b Maps of the predicted average 1° × 1° carbon concentration in the epipelagic (0–200 m; a) and mesopelagic layer (200–1000 m; b). c Integrated carbon biomass as a function of latitude for both layers. Regression curves were derived using Generalized Additive Models. Note the logarithmic scaling for carbon biomass. d Total carbon biomass for Rhizaria groups in both layers. Only groups whose model R² calculated by random cross-validation is >0.05 are shown (see also Supplementary Table 3). e Global and regional contribution of large mesopelagic Phaeodaria to gravitational particulate organic carbon (POC) flux attenuation, based on the ratio of their annual carbon demand to the respective median annual carbon export (i.e., transport out of the euphotic zone) as reported elsewhere^32,33,34 and summarized in Supplementary Table 5. Bars show the ratio calculated with the single export value available or the median value when more than one export value was available. In the latter case, dots show export values used to calculate the median. Error bars are represented according to the range of observed export values. No POC export measures were available for the subarctic Pacific and Atlantic. f Global and regional integrated daily carbon demand of large mesopelagic Phaeodaria. Dots show mean values, error bars show regional mean ± standard deviation as presented in Supplementary Table 5. The number of 1° × 1° cells used to derive statistics are displayed below for each region. a, b Maps were created using the R software version 4.0.3 (ref. ⁶³).