Dear Editor, We are pleased to submit the revised version of the manuscript entitled “Distribution of planktonic foraminifera in the Subtropical South Atlantic: depth hierarchy of controlling factors” for consideration for publication

Temperature appears to be the best predictor of species composition of planktonic foraminifera communities, making it possible to use their fossil assemblages to reconstruct sea surface temperature (SST) variation in the past. However, the role of other environmental factors potentially modulating the spatial and 15 vertical distribution of planktonic foraminifera species is poorly understood. This is especially relevant for environmental factors affecting the subsurface habitat. If such factors play a role, changes in the abundance of deeper subsurface-dwelling species may not solely reflect SST variation. In order to constrain the effect of subsurface parameters on species composition, we here characterize the vertical distribution of living planktonic foraminifera community across an E-W transect through the subtropical South Atlantic Ocean, where SST 20 variability iswas small but the subsurface water mass structure changeschanged dramatically. Four planktonic foraminifera communities could be identified across the top 700 m of the E-W transect. Gyre and Agulhas Leakage surface faunas were predominantly composed of Globigerinoides ruber, Globigerinoides tenellus, Trilobatus sacculifer, Globoturborotalita rubescens, Globigerinella calida, Tenuitella iota and Globigerinita glutinata, and only differed in terms of relative abundances (community composition). Upwelling fauna was 25 dominated by Neogloboquadrina pachyderma, Neogloboquadrina incompta, Globorotalia crassaformis and Globorotalia inflata. Thermocline fauna was dominated by Tenuitella fleisheri, Globorotalia truncatulinoides and Globorotalia scitula in the western sidewest, and by G. scitula in the eastern side of the basineast. The largest part of the standing stock was consistently found in the surface layer, but SST was not the main predictor of species composition, neither for the totaldepth-integrated fauna at each stationacross the stations nor in 30 analyses considering eachat individual depth layer separatelylayers. Instead, we identified a consistentpattern of vertical pattern in stacking of different parameters controlling species composition at different depths, in which the parameters appear to reflect, reflecting different aspects of the pelagic habitat. Whereas productivity appears to dominate in the mixed layer (060 m), physical-chemical parameters are properties (temperature, salinity) become important at depth immediately below (60-100 m), followed by parameters related to the degradation of 35 organic matter (100-300 m),intermediate depths and parameters describing the dissolvedin the subsurface, a complex combination of factors including oxygen availability (>300 m). concentration is required to explain the assemblage composition. These results indicate that the seemingly straightforward relationship between assemblage composition and SST in sedimentary assemblages reflects vertically and seasonally integrated processes that are only indirectly linked to SST. ThisIt also implies that fossil assemblages of planktonic 40 foraminifera should also contain a signature of subsurface processes, which could be used for paleoceanographic reconstructions.