Table 2.
Parameter | Surface | Pore water, 5–10 cm | Pore water, 55–60 cm | Pore water, acidified | Pore water, Fe-precipitated |
O/C ratio | 0.43 | 0.43 | 0.44 | 0.42 | 0.41 |
H/C ratio | 1.12 | 1.08 | 1.05 | 1.13 | 1.17 |
N/C ratio | 0.10 | 0.09 | 0.08 | 0.09 | 0.09 |
S/C ratio | 0.06 | 0.06 | 0.06 | 0.06 | 0.06 |
P/C ratio | 0.05 | 0.04 | 0.05 | 0.04 | 0.04 |
CHO, % | 45 | 45 | 51 | 48 | 46 |
CHON, % | 33 | 35 | 31 | 34 | 32 |
CHON1, % | 18 | 19 | 20 | 20 | 20 |
CHON2, % | 10 | 11 | 9 | 10 | 9 |
CHOS1, % | 17 | 14 | 15 | 13 | 15 |
CHONS, % | 2 | 3 | 1 | 2 | 3 |
CHOP, % | 1 | <1 | 1 | 1 | 1 |
Other, % | 2 | 4 | 2 | 3 | 4 |
Aromatic, % | 27.9 | 31.9 | 34.8 | 25.7 | 20.0 |
Condensed aromatic, % | 8.6 | 9.7 | 10.6 | 6.3 | 3.6 |
Elemental ratios are number-averaged for all formulas found per sample. The percentages of aromatic and condensed aromatic compounds per sample were identified using the modified AI (13). CHON, all compounds containing at least one nitrogen (including CHON1–2S1 and CHON1–2P1); CHONS, compounds containing carbon, hydrogen, oxygen, nitrogen, and sulfur; CHOP, compounds containing carbon, hydrogen, oxygen, and phosphorus; N/C ratio, nitrogen-to-carbon ratio; P/C ratio, phosphorus-to-carbon ratio; S/C ratio, sulfur-to-carbon ratio.