Table 1.
Soil organic carbon concentrations (% SOC), SOC 13/12C isotope mixing ratios (δ13CSOC) and corresponding P values of paired, two sided t-tests of soil density fractions and bulk soil in 2003 and after resampling in 2010. Values refer to the control treatment without additional N deposition.
| δ13CSOC (means ± 1 SE) | % SOC (means ± 1 SE) | P | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Fraction | 2003 | 2010 | 2003 | 2010 | δ13C | %C | ||||
| <1.4 | −25.93 | (0.052) | −27.01 | (0.047) | 21.01 | (0.594) | 30.27 | (0.818) | 0.0000 | 0.0000 |
| <1.8 | −26.43 | (0.032) | −26.86 | (0.093) | 25.09 | (0.524) | 27.48 | (0.928) | 0.0002 | 0.0198 |
| >1.8 | −25.76 | (0.044) | −26.09 | (0.059) | 12.48 | (0.252) | 11.31 | (0.239) | 0.0003 | 0.0021 |
| >2.2 | −25.03 | (0.035) | −25.23 | (0.033) | 5.02 | (0.194) | 3.98 | (0.103) | 0.0003 | 0.0001 |
| bulk | −25.31 | (0.033) | −25.56 | (0.017) | 8.51 | (0.237) | 10.09 | (0.236) | 0.0023 | 0.0001 |