The aim of the study was to evaluate changes in chemical composition of litter during early stages of decomposition based on a comparative analysis of published C-13 NMR spectra. We collected over 130 C-13 NMR spectra from peer-reviewed articles that contained spectra for undecomposed litter and for litter in at least one stage of decomposition.
We measured the areas of peaks representing individual chemical components and interpreted the proportions of those peak areas as proportions of respective chemical components. Results indicate that fresh herb litter tends to contain more carbohydrates and less phenolic compounds and to have lower remaining mass, indicating faster decomposition.
Carbohydrates consistently decrease during decomposition, while the proportions of aromatic and aliphatic compounds increase. Changes in the proportions of individual chemical components are negatively correlated with their initial content.
The proportion of aromatic components correlates positively with the C/N ratio and negatively with the decomposition constant.