Fig. 3.
Canonical correspondence analysis of the bacterioplankton community structure from samples in Lake Bourget (A and B) and Lake Annecy (C and D) at 2 m (A) versus 50 m (B) and at 3 m (C) versus 45 m (D), respectively, using physicochemical and biological parameters. Arrows point in the direction of increasing values of each variable. The length of the arrow indicates the degree of correlation with the represented axes. The position of samples relative to arrows is interpreted by projecting the points on the arrow and indicates the extent to which a sample bacterial community structure is influenced by the environmental parameter represented by that arrow. Chl a, chlorophyll a; Temp, Temperature; O2, dissolved oxygen; NH4, ammonium; NO3, nitrates; Pt, total phosphorus; SiO2, silicates; PNF, pigmented nanoflagellates; HNF, heterotrophic nanoflagellates.