Accumulation of n-alkanes and carboxylic acids in peat mounds

Resumo

The quantitative and qualitative compositions of n-alkanes and carboxylic acids have been identified, and the features of their vertical stratification in peat mound profiles of the forest-tundra zone of Komi Republic have been revealed. The composition of n-alkanes (structures with C₂₃, C₂₅, C₂₇, C₂₉, and C₃₁) and carboxylic acids (C₂₄, C₂₆, and C₂₈) and their proportions make it possible to determine changes in plant communities of peat mounds with time and can be used as markers for the degree of decomposition of organic matter. In cryogenic horizons, the contents of n-alkanes (mainly C₂₃, C₂₅, and C₂₇) and carboxylic acids (C₂₄, C₂₆, and C₂₈) significantly decrease because of the different botanic composition of cryogenic horizons (grass–woody residues) and seasonally thawing horizons (moss–subshrub residues) and the almost complete stopping of the equilibrium accumulation and transformation of organic compounds in permafrost.