highly significantp < 0.001
Bacterioplankton Community Structure Abundances of the bacterioplankton phylogenetic groups detected by CARD-FISH generally covaried with total bacterioplankton cells as shown by highly significant linear correlations of all phylogenetic groups (mean r 2 = 0.73, range 0.62–0.90; p < 0.001) except the Polaribacter cluster ( Figure 5 ).