Table 2.
Expected associations between functional traits of freshwater phytoplankton and abiotic variables associated with potential storm effects in lakes
| Phytoplankton functional traits | |||||||
|---|---|---|---|---|---|---|---|
| Flagella/motility (controlled vertical migration) | Small cell size (rapid growth, slow settling) | Spherical colonies (nutrient acquisition, grazing resistance) | Filamentous (light capturing efficiency) | Gas‐vesicles/mucilage (buoyancy regulation/controlled vertical migration) | Silicaceous (silica‐limited; rapid sinking) | N2‐fixation | |
| Example taxa | Cryptomonas marsonnii (Cryptophyceae) | Cyclotella spp. (diatoms) | Volvox spp. (green algae) | Planktothrix agardhii (Cyanobacteria), Mougeotia spp. (green algae) | Microcystis, Planktothrix rubescens (Cyanobacteria) | Aulacoseira spp. (diatoms) | Aphanizomenon spp. (Cyanobacteria) |
| Example references | Jones (1988), Clegg, Maberly, and Jones (2003), Salonen, Jones, and Arvola (1984) | Rühland et al. (2015)* | Reynolds, Wiseman, and Clarke (1984) | Scheffer, Rinaldi, Gragnani, Mur, and van Nes (1997), Reynolds et al. (2002) | Reynolds, Oliver, and Walsby (1987)* | Rühland et al. (2015)* | Paerl and Otten (2013) |
| Abiotic variables | |||||||
| Nutrient loading (internal or external) | − | + | − | ± | ± | + | ± |
| Decreased Z eu/Z mix | + | − | + | + | + | + | − |
| Flushing | − | + | − | + | − | − | − |
| Low temperature | − | + | − | − | − | + | − |
| Turbulence/mixing strength | − | + | − | ± | − | + | − |
| Stable, stratified environment | + | − | + | − | + | − | + |
A “+” indicates a generally positive association (the trait becomes more dominant after a physical storm effect), while “−” indicates a generally negative association. A “±” indicates the possibility of positive or negative association, depending on antecedent conditions. Changes in trait dominance within the phytoplankton community reflects trait variation within a taxonomic group as well as turnover among groups (Litchman & Klausmeier, 2008). The physiological/ecological functions of each trait are given in parentheses (derived from Salmaso et al., 2015). Expected associations, and example genera or species that exhibit each trait, were derived from the cited references, and may not be universally applicable. The realized environmental tolerances of a species are subject to the simultaneous influence of multiple traits (Litchman et al., 2010). An “*” indicates a literature review.