Sanderman and KramerDOM production and chemistry

Supplemental Material

Supplemental Table 1. Initial characteristics of soils used in leaching experiment.

Site1 / Horizon / Thickness2 (cm) / Mass2 (g) / Carbon
(%) / Nitrogen (%) / C/N ratio / Lignin3 (%) / Lignin/N ratio
Thurston, Hawai’i
(0.3 ky) / O / 4.7 / 39.8 / 47.5 / 1.15 / 42.2 / 29.1 / 25.3
Oie / 2.0 / 12.0 / 48.7 / 0.95 / 51.3 / 26.1 / 16.9
Oa / 2.7 / 25.7 / 47.0 / 1.24 / 37.9 / 31.8 / 15.6
Laupahoehoe, Hawai’i
(20 ky) / O / 7.4 / 73.2 / 36.4 / 1.48 / 24.8 / 25.0 / 13.8
Oie / 1.8 / 11.1 / 51.4 / 1.39 / 36.9 / 22.6 / 18.9
Oa / 6.5 / 62.2 / 33.8 / 1.49 / 22.6 / 35.0 / 25.6
Pu’u Eke, Hawai’i
(350 ky) / O / 6.7 / 69.8 / 45.1 / 1.72 / 28.0 / 26.9 / 23.5
Oie / 1.9 / 12.8 / 42.8 / 0.96 / 44.7 / 25.8 / 14.6
Oa / 5.2 / 56.2 / 45.7 / 1.89 / 24.2 / 27.6 / 14.4
Pu’uKolekole, Moloka’i
(1400 ky) / O / 8.7 / 86.7 / 50.5 / 1.52 / 33.8 / 21.0 / 18.6
Oie / 2.0 / 13.9 / 49.1 / 1.10 / 44.6 / 18.8 / 27.5
Oa / 7.0 / 66.6 / 50.8 / 1.61 / 31.6 / 23.2 / 16.3
Koke’e,
Kaui
(4100 ky) / O / 7.9 / 111.5 / 44.6 / 1.76 / 26.5 / 33.2 / 26.9
Oie / 2.0 / 13.6 / 53.4 / 1.10 / 48.6 / 32.1 / 17.1
Oa / 6.9 / 102.5 / 43.4 / 1.84 / 23.6 / 34.3 / 29.2

1Substrate age given in parentheses

2Mean thickness and mass of packed cores for leaching experiment

3Percent lignin determined by applying a molecular mixing model to 13C NMR results

Supplemental Figure 1. Time series of horizon averaged CO2 fluxes (A) and DOC concentration in core leachates (B). Error bars indicate one standard error (n = 15).


Supplemental Table 2. Percent distribution of signal intensity across major shift regions and results from molecular mixing model for NMR spectra shown in Figure 3.

Shift region / Major C type / Th (0.3) / La (20) / Pu (350) / Mo (1400) / Ko (4100) / Th (0.3) / La (20) / Pu (350) / Mo (1400) / Ko (4100)
Oie horizon organic material / DOM effluent from whole O core
0 - 45 / Alkyl / 23.3 / 14.5 / 24.6 / 16.8 / 22.9 / 27.0 / 25.5 / 27.7 / 23.4 / 24.9
45 - 60 / N-Alkyl/Methoxyl / 10.1 / 8.6 / 11.9 / 7.6 / 10.5 / 10.7 / 10.0 / 10.7 / 10.1 / 10.1
60 - 95 / O-Alkyl / 39.8 / 45.8 / 37.0 / 42.0 / 33.6 / 26.0 / 24.9 / 24.3 / 25.5 / 24.4
95 - 110 / Di-O-Alkyl / 9.7 / 10.8 / 9.2 / 11.3 / 12.2 / 6.2 / 6.5 / 6.4 / 7.0 / 7.0
110 - 145 / Aromatic / 10.3 / 11.6 / 9.2 / 13.6 / 9.8 / 13.1 / 13.5 / 12.8 / 14.5 / 13.1
145 - 165 / Phenolic / 4.2 / 4.2 / 4.6 / 5.0 / 6.1 / 5.0 / 5.9 / 5.4 / 5.9 / 5.6
165 - 215 / Amide/Carboxyl / 2.6 / 4.6 / 3.5 / 3.5 / 4.9 / 12.0 / 13.9 / 12.6 / 13.7 / 15.0
Molecular Mixing Model Component / Carbohydrate / 50.6 / 57.6 / 45.6 / 39.9 / 40.5 / 27.1 / 25.6 / 25.0 / 26.3 / 25.0
Protein / 6.3 / 8.8 / 9.2 / 10.4 / 11.5 / 8.8 / 11.7 / 10.7 / 11.8 / 11.2
Lignin / 26.1 / 27.0 / 25.8 / 18.8 / 32.1 / 31.6 / 31.5 / 31.4 / 33.6 / 30.8
Lipid / 17.0 / 6.4 / 19.4 / 30.9 / 16.0 / 20.9 / 17.6 / 20.9 / 14.9 / 16.9
Carbonyl / 0.0 / 0.3 / 0.0 / 0.0 / 0.0 / 11.7 / 13.6 / 11.9 / 13.3 / 16.1

Supplemental Table 3.Percent distribution of major biomolecular components based upon NMR-molecular mixing model results from litter and DOM samples collected from a range of ecosystem types.

Litter type / Carbohydrate / Protein / Lignin / Lipid / Carbonyl
Litter samples
Ohi'a forest / 1 / 48.1 / 4.9 / 38.2 / 7.5 / 1.3
Redwood-Douglas fir / 2 / 46.8 / 7.2 / 26.0 / 17.9 / 2.1
Mixed grassland / 2 / 71.3 / 8.3 / 16.6 / 2.6 / 1.2
Eucalyptus globulus / 3 / 40.9 / 7.9 / 31.4 / 9.8 / 10.0
Wheat residues / 3 / 61.5 / 10.5 / 17.8 / 3.6 / 6.6
DOM samples
Ohi'a forest / 1 / 25.8 / 10.8 / 31.8 / 18.2 / 13.3
Redwood-Douglas fir / 2 / 26.5 / 6.3 / 35.3 / 12.7 / 19.2
Mixed grassland / 2 / 24.9 / 14.2 / 40.1 / 4.1 / 16.7
Eucalyptus globulus / 3 / 21.4 / 9.0 / 39.7 / 13.8 / 16.4
Wheat residues / 3 / 28.8 / 18.6 / 29.9 / 13.0 / 11.7
1 mean value across all 5 sites in this study
2 Sanderman et al. (2008)
3 Sanderman (unpublished)

Supplement Table 4. Bioavailability experiment results.

Initial characteristics / Final characteristics
Site / Horizon / DOCa
(mg L-1) / SUVA (L mg C-1 m-1) / DOC/DON / Al (mg L-1) / C mass loss
(%) / SUVA (L mg C-1 m-1)
Th / O / 51.4± 12.5 / 4.37 ± 0.16 / 35.8± 5.8 / 0.49 ± 0.16 / 10.3± 7.4 / 4.90± 0.13
Oie / 32.2± 9.0 / 3.86 ± 0.13 / 54.7 ± 3.5 / 0.12 ± 0.03 / 16.7 ± 2.3 / 4.57 ± 0.1
Oa / 34.7 ± 9.2 / 4.68 ± 0.10 / 42.1 ± 17.0 / 0.62 ± 0.13 / 8.6± 2.2 / 5.17 ± 0.07
La / O / 113.9± 28.7 / 4.22 ± 0.12 / 11.2 ± 7.0 / 0.93 ± 0.44 / 9.6 ± 8.6 / 4.85 ± 0.45
Oie / 86.0± 15.8 / 4.03 ± 0.04 / 34.2 ± 13.1 / 0.26 ± 0.10 / 2.4 ± 1.4 / 4.18 ± 0.22
Oa / 101.9± 30.0 / 4.45 ± 0.16 / 10.9 ± 3.8 / 1.24 ± 0.17 / 0.0± 1.9 / 4.66 ± 0.1
Pu / O / 86.0± 15.8 / 4.03 ± 0.04 / 22.3 ± 2.2 / 0.73 ± 0.20 / 2.4 ± 1.4 / 4.18 ± 0.22
Oie / 69.1± 23.9 / 4.14 ± 0.19 / 44.0 ± 14.6 / 0.21 ± 0.04 / 16.4 ± 0.9 / 5.00± 0.21
Oa / 113.8 ± 33.4 / 4.52 ± 0.20 / 22.3 ± 1.0 / 0.65 ± 0.07 / 9.8± 4.6 / 5.20± 0.28
Mo / O / 168.5 ± 29.9 / 4.55 ± 0.07 / 24.1 ± 2.5 / 0.42 ± 0.14 / 9.1± 2.2 / 5.20± 0.17
Oie / 98.5 ± 12.0 / 4.53 ± 0.47 / 34.4 ± 15.8 / 0.24 ± 0.17 / 13.2 ± 8.3 / 5.20± 0.08
Oa / 106.7 ± 40.5 / 4.93 ± 0.64 / 42.5 ± 22.6 / 0.35 ± 0.18 / 10.8 ± 10.1 / 5.79 ± 0.2
Ko / O / 77.1 ± 17.5 / 4.49 ± 0.29 / 27.0 ± 7.1 / 0.63 ± 0.28 / 6.6± 1.4 / 5.04 ± 0.25
Oie / 49.3 ± 8.2 / 4.17 ± 0.19 / 40.8 ± 10.3 / 0.01 ± 0.06 / 19.5 ± 4.5 / 5.10± 0.09
Oa / 75.9 ± 38.9 / 4.76 ± 0.13 / 30.9 ± 6.8 / 0.66 ± 0.25 / 6.4± 2.7 / 5.25 ± 0.21
a initial value before dilution to approximately 30 mg C L-1

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