TY - JOUR N2 - Humic acids, isolated from selected soils of Grønfjorden area (Spitsbergen) were investigated in terms of molecular composition and resistance of decomposition. The degree of soils organic matter stabilization has been assessed with the use of modern instrumental methods (nuclear magnetic resonance spectroscopy (CP/MAS 13C-NMR). Analysis of the humic acids showed that aromatic compounds prevail in the organic matter formed in cryoconites, located on the glaciers surfaces. The predominance of aliphatic fragments is revealed in the soils in tidal zone that form on the coastal terrace. This could be caused by sedimentation of fresh organic matter exhibiting low decomposition stage due to the harsh climate and processes of hydrogenation in the humic acids, destruction of the C-C bonds and formation of chains with a high hydrogen content. These processes result in formation of aliphatic fragments in the humic acids. In general, soils of the studied region characterizes by low stabilized soil organic matter which is indicated by low aromaticity of the HAs. L1 - http://czasopisma.pan.pl/Content/111976/PDF/Polish%20Polar%20Res.%202-19%203-V.Polyakov.pdf L2 - http://czasopisma.pan.pl/Content/111976 PY - 2019 IS - No 2 EP - 120 DO - 10.24425/ppr.2019.128369 KW - Arctic KW - Svalbard KW - CP/MAS 13C-NMR KW - elemental composition KW - organic matter A1 - Polyakov, Vyacheslav A1 - Zazovskaya, Elya A1 - Abakumov, Evgeny PB - Polish Academy of Sciences PB - Committee on Polar Research VL - vol. 40 DA - 2019.06.13 T1 - Molecular composition of humic substances isolated from selected soils and cryconite of the Grønfjorden area, Spitsbergen SP - 105 UR - http://czasopisma.pan.pl/dlibra/publication/edition/111976 T2 - Polish Polar Research ER -