Associations between lake phytoplankton community and growth factors — a canonical correlation analysis

Canonical correlation analysis was used to study the associations between the most prevalent phytoplankton species and nine physical and chemical growth factors in a polyhumic Finnish lake. The analysis was made (a) to the ten species with the greatest mean biomass in the data over one growth season and (b) to the ten species providing the greatest canonical correlation with the growth factors. The latter species were detected using an exchange type procedure. The analysis showed strong associations within phyla. Especially the most problematic phylum with respect to the use of the lake, the cyanobacteria, had a pronounced mutual association, as they correlated negatively with the N/P ratio as positively with phosphorus.