Table 2.

Mean values for known Microcystis genotypes measured from the Lake Mendota Deep Hole location between the years 2000–2010.

Genotype	Pre-toxic	Toxic	Post-toxic	K-W
Microcystis 215 (%)	8.1	5.6	3.7	c
Microcystis 506 (%)	0.5	1.4	1.7	a
Microcystis 660 (%)	0.2	13.0	14.5	a, c
Total Microcystis (%)	8.8	20.0	19.9	a, c

All of the data were split into three time periods (phases) based on the 2009–2011 microcystin data. The toxic phase represents the period when mean microcystin concentrations were significantly greater than 1 μg L⁻¹ (days 170–250). Significance between the phases was tested using a Kruskal–Wallis test (K–W; p < 0.05). a, significant difference between pre-toxic and toxic phases; c, significant difference between pre-toxic and post-toxic phases.