The hydrophobic index (HB) for both compost materials was low
(HB = 0.7), which suggests that hydrophilic carbons predominate.
The lignin ratio was relatively high (LR = 1–1.1). Total aromaticity was
calculated by dividing the peak areas of aromatic C (110–160 ppm) as
percentage of peak areas of aliphatic-C (0–110 ppm) plus aromatic carbon
(Schnitzer et al., 1991). Results showed that both compost materials
had 75–77% aliphatic and 23–25% aromatic characteristics, with no difference
between the two composts.