Table 2.
Frequency of occurrence of cyanotoxins and mean concentrations in experimental biocrust plug samples and controls in relation to light intensity exposure. Each experimental treatment was performed and analyzed in triplicate. Microcystins were not present in any of the analyzed samples.
| Light intensity (μmole/m2/s; W/m2) | Chlorophyll-a (μg/ml/g) |
Total AEG (μg/ml/g) |
Total BMAA (μg/ml/g) |
Total DAB (μg/ml/g) |
Anatoxin-a(S) (guanitoxin) (mg/L/g) |
|---|---|---|---|---|---|
| % occurrence (mean concentration; standard deviation) | |||||
| High (970–1900; 210.9–413) | 96.3 (49.41; ±69.4) |
96.3 (0.16; ±0.07) |
14.8 (0.03; ±0.01) |
100 (0.44; ±0.11) |
74.1 (4.07; ±7.5) |
| Medium (430–970; 93.5–210.9) |
96.3 (92.02; ±62.66) |
81.5 (0.19; ±0.08) |
81.5 (0.06; ±0.04) |
70.4 (0.53; ±0.2) |
51.9 (25.57; ±11.78) |
| Low (51–430; 11.1–93.5) |
96.3 (105.64; ±72.47) |
100 (0.17; ±0.09) |
100 (0.08; ±0.05) |
100 (0.55; ±0.14) |
77.8 (20.37; ±16.65) |
|
Controls No Light, Desiccated |
100 (55.82; ±8.12) |
33.3 (0.04; ±0.07) |
33.3 (0.04; ±0.06) |
33.3 (0.22; ±0.39) |
0 (0; 0) |