TABLE 1.
Ambient and spiked THg and MeHg concentrations and MPP results
| Site | Amendment | Ambient conditions |
Spiked conditions |
MPPa |
||||
|---|---|---|---|---|---|---|---|---|
| THg (μg/g) | MeHg (pg/g) | 201THg (μg/g) | Me201Hg (pg/g) | μg MeHg/kg THg spiked/day (10−4) | % | Groupb | ||
| HC | None | 3.5 × 10−3 ± 0.3 × 10−3 | 1.1 ± 0.2 | 4.7 × 10−3 ± 0.1 × 10−3 | 0.7 ± 0.1 | 1.5 ± 0.2 | 0.015 ± 0.002 | A |
| Cellobiose | 3.6 × 10−3 ± 0.2 × 10−3 | 0.7 ± 0.1 | 4.1 × 10−3 ± 0.5 × 10−3 | 0.4 ± 0.0 | 1.0 ± 0.1 | 0.010 ± 0.001 | A | |
| Lactate | 2.7 × 10−3 ± 0.2 × 10−3 | 1.1 ± 0.1 | 5.2 × 10−3 ± 0.2 × 10−3 | 0.8 ± 0.0 | 1.5 ± 0.1 | 0.015 ± 0.001 | A | |
| Ethanol | 2.7 × 10−3 ± 0.1 × 10−3 | 1.1 ± 0.2 | 4.5 × 10−3 ± 0.7 × 10−3 | 0.8 ± 0.2 | 1.8 ± 0.1 | 0.018 ± 0.001 | AB | |
| Acetate | 3.6 × 10−3 ± 0.7 × 10−3 | 0.9 ± 0.2 | 5.1 × 10−3 ± 0.2 × 10−3 | 0.6 ± 0.1 | 1.2 ± 0.2 | 0.012 ± 0.002 | A | |
| Propionate | 3.0 × 10−3 ± 0.3 × 10−3 | 1.0 ± 0.2 | 4.3 × 10−3 ± 0.5 × 10−3 | 0.5 ± 0.1 | 1.2 ± 0.1 | 0.011 ± 0.001 | A | |
| Methanol | 3.9 × 10−3 ± 0.3 × 10−3 | 0.9 ± 0.1 | 5.9 × 10−3 ± 0.5 × 10−3 | 0.6 ± 0.1 | 1.0 ± 0.2 | 0.010 ± 0.002 | A | |
| NOAA | None | 1.2 ± 0.6 | 310 ± 11 | 4.7 ± 1.0 | 980 ± 240 | 2.1 ± 1.1 | 0.021 ± 0.011 | AB |
| Cellobiose | 0.9 ± 0.3 | 330 ± 120 | 3.6 ± 0.4 | 950 ± 190 | 2.6 ± 0.6 | 0.026 ± 0.006 | A | |
| Lactate | 2.6 ± 2.8 | 450 ± 290 | 4.6 ± 0.3 | 1,300 ± 150 | 2.9 ± 0.3 | 0.029 ± 0.003 | ABCD | |
| Ethanol | 0.7 ± 0.3 | 230 ± 47 | 5.0 ± 1.4 | 1,600 ± 460 | 3.2 ± 1.7 | 0.032 ± 0.017 | ABCD | |
| Acetate | 1.2 ± 1.0 | 280 ± 150 | 5.1 ± 1.0 | 1,400 ± 530 | 2.7 ± 1.8 | 0.027 ± 0.018 | ABC | |
| Propionate | 0.6 ± 0.4 | 150 ± 52 | 4.4 ± 0.7 | 1,400 ± 480 | 3.2 ± 1.5 | 0.032 ± 0.015 | ABCD | |
| Methanol | 0.7 ± 0.2 | 210 ± 7 | 4.9 ± 1.1 | 1,400 ± 150 | 2.9 ± 0.9 | 0.028 ± 0.009 | ABCD | |
| NH | None | 3.3 ± 0.7 | 2,700 ± 250 | 4.4 ± 0.5 | 2,000 ± 420 | 4.5 ± 0.7 | 0.045 ± 0.007 | BCD |
| Cellobiose | 3.4 ± 1.2 | 1,600 ± 98 | 4.6 ± 0.3 | 640 ± 64 | 1.4 ± 0.1 | 0.014 ± 0.001 | A | |
| Lactate | 3.4 ± 0.7 | 1,900 ± 100 | 4.5 ± 0.7 | 2,400 ± 650 | 5.3 ± 0.8 | 0.053 ± 0.008 | CD | |
| Ethanol | 2.4 ± 0.2 | 1,900 ± 340 | 4.4 ± 0.4 | 2,400 ± 930 | 5.4 ± 2.0 | 0.054 ± 0.020 | CD | |
| Acetate | 3.2 ± 0.5 | 2,100 ± 330 | 4.8 ± 0.6 | 1,700 ± 330 | 3.5 ± 1.0 | 0.035 ± 0.010 | ABCD | |
| Propionate | 3.0 ± 0.8 | 1,600 ± 160 | 4.0 ± 0.6 | 1,400 ± 310 | 3.4 ± 0.4 | 0.034 ± 0.004 | ABCD | |
| Methanol | 4.3 ± 1.3 | 2,200 ± 150 | 3.9 ± 0.6 | 2,100 ± 290 | 5.5 ± 1.1 | 0.055 ± 0.011 | D | |
a
MPP, methylmercury production potential.
b
In the "Group" column, different letters indicate a significant difference using Tukey’s honestly significant difference test and a family-wide error rate of 5%.