Table 1 δ13C values and %carbon of non-demineralised soil samples cored in August 2000 from experimental control sites and from sites treated with paper sludge in 1992. Light-blue chunks of solidified paper sludge found on the soil surface yielded a %C value of 17.36% and δ13C value of -16.84‰. Sample deviation: ± 0.05% and ± 0.05‰ (3 repeats)
From: 13C/12C composition, a novel parameter to study the downward migration of paper sludge in soils†
Wood soils | Crop soils | |||||||
|---|---|---|---|---|---|---|---|---|
C(%) | δ13C (‰) | C(%) | δ13C (‰) | |||||
Horizon, thickness | Control site | Paper site | Control site | Paper site | Control site | Paper site | Control site | Paper site |
Litter ~3 cm, grassesa | 40.24 | 44.94 | -27.63 | -27.24 | 44.25 | 43.01 | -28.20 | -27.58 |
Blue sludgeb, 10 cm | 18.28 | -20.97 | 5.82 | -22.81 | ||||
Black humicc, 10 cm | 4.80 | 4.34 | -27.66 | -25.72 | 2.50 | 5.20 | -27.48 | -21.84 |
Dark-brownc, 20 cm | 2.26 | 2,30 | -27.79 | -27.63 | 1.04 | 0.56 | -28.16 | -28.70 |
Light-brownc, 20 cm | 1.03 | 1.03 | -27.35 | -27.34 | 0.55 | 0.31 | -27.72 | -27.81 |