Lignin litter

Plant litter consists mainly of sugars, cellulose, hemicellulose, lignin, waxes, and polyphe-... 

Hammel, K. E. 1997. Fungal degradation of lignin. In Driven by Nature Plant Litter Quality and Decomposition (G. Cadisch, and K. E. Giller, Eds.), pp. 33—46. CAB International, Wallingford. 

Melillo, J. M., Aber, J. D., and Muratore, J. F. (1982). Nitrogen and lignin control of hardwood leaf litter decomposition dynamics. Ecology 63(3), 621-626. 

Osono, T., Takeda, H., and Azuma, J.-i. (2008). Carbon isotope dynamics during leaf litter decomposition with reference to lignin fractions. Ecol. Res. 23(1), 51-55. 

Meentemeyer, V. (1978) Macroclimate and lignin control of litter decomposition rates. Ecology 59, 465-472. 

Miltner, A., and Zech, W. (1998) Beech leaf litter lignin degradation and transformation as influenced by mineral phases. Org. Geochem. 28, 457 -63. 

Humic substances seem to be formed primarily by the degradation of lignin, complicated by interactions with other compounds, such as proteins and amino acids, produced from plant litter. Maillard536,537 already recognised that the condensation of sugars with amino acids, peptides, and proteins also plays a role in the formation of humic substances. 

Aber, J. P. Melillo, J. M. (1982). Nitrogen immobilization in decaying hardwood leaf litter as a function of initial nitrogen and lignin content. Canadian Journal of Botany, 60, 2263-9. 

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