Table 1.
The signal-to-noise (S/N) ratio for the National Lakes Assessment (NLA) cyanobacterial harmful algal bloom (cyanoHAB) metrics among all observations collected in the 2007 survey, all observations collected in the 2012 survey, and all observations pooled across the 2007 and the 2012 NLAs. To calculate S/N, the variation among lakes (signal) is divided by the variation among repeat samples collected in the same lake (noise).
| Variable | S/N Within 2007 NLA | S/N Within 2012 NLA | S/N Across 2007 & 2012 NLAs |
|---|---|---|---|
|
| |||
| Microcystina | 10.0 | 15.3 | 10.5 |
| Microcystinb | 13.4 | 20.9 | 14.4 |
| Cyanobacteria | 5.7 | <0.1 | <0.1 |
| Chlorophyll a | 2.7 | 12.0 | 3.9 |
a
Only microcystin concentrations above detection limit of 0.1 μg/L included
b
Microcystin observations below the detection limit were included by recoding to have a value of zero