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, SA: small acids, CAR: carbohydrates, FA: fatty acids, 646 PHE: phenolic compounds, LMWFA: low molecular weight fatty acids, pcVEG: percentage of vegetation

. S/v, Ac) V : ratio of aldehyde to acid moieties for vanillyl, ratio of syringyl to vanillyl acids

, Figure 1. (a) Location of Igarka and permafrost status in the Republic of Russia. (b) Sampling 675 area, with location of sampling points. Pictures are representative of sampling locations

, Data from IPA (International Permafrost Association) and Google Earth. , sediment porewater of lake and surface water of lakes. (b) Proportion of 706 permafrost to DOM. The distribution corresponds to calculation with atmospheric signature 707 ranging from 1980 to 2015 (sampling date). SB= small bogs, LB = large bogs