Fig. 5: Environmental drivers of community structure.

Partial Least Square regression between environmental parameters and the abundance of microbial families, identifying seasonal groupings in the WSC (a) compared to both seasonal and polar/Atlantic-influenced groupings in the EGC (b). Only correlation coefficients > 0.5 were considered. Temp: water temperature; O2 conc: oxygen concentration; O2 sat: oxygen saturation; PW: proportion of Polar Water; ice cover: percent ice cover on a given sampling event; past ice: percent ice cover integrated over the time between sampling events; CO2: partial CO2 pressure.