TABLE 2.
MPN estimates of bacterial cell density before and after incubation of periphyton samples amended with 0, 1, or 5 mM As(V)
| AS(V) added (mM) | MPN (cells/ml)
|
|||
|---|---|---|---|---|
| Beginning time point
|
Final time pointa
|
|||
| Avg | Range | Avg | Range | |
| 0 | 1.9 × 102 | 1.5 × 102-2.4 × 102 | 1.3 × 104 | 2.3 × 103-2.4 × 104 |
| 1.0 | 2.2 × 103 | 1.4 × 102-4.3 × 103 | 5.1 × 104 | 9.3 × 103-9.3 × 104 |
| 5.0 | 2.5 × 102 | 0.7 × 102-4.3 × 102 | 9.5 × 105 | 4.3 × 105-1.5 × 106 |
a
The incubation times were 10 days for the 1 mM addition and 58 days for the 0 and 5 mM additions. The range of values determined for two periphyton incubations of each condition are presented along with the average for each time point.