Carbohydrate compositional trends throughout Holocene sediments of an alpine lake (Lake Cadagno)

Carbohydrates are a ubiquitous constituent of organisms and contribute significantly to sedimentary organic carbon pools. Yet, the factors that control degradation long-term preservation carbohydrates not well understood. Here, we investigate carbohydrate pool sizes chemical compositions in high-altitude, meromictic Lake Cadagno (Switzerland) over 13,500-year-old succession has recorded past changes from oxic anoxic conditions consists mostly intercalations lacustrine sediments terrestrial-derived sediments. Analyses matter composition by pyrolysis gas chromatography/mass spectrometry (Py-GC/MS) show selectively preserved other constituents time. The products levosugars (potentially cellulose-derived) (alkyl)furans furanones pectin-derived) dominate both terrestrially derived sediment layers, suggesting aquatic sources these compounds. Carbohydrate monomer analyses indicate galactose glucose as dominant monomers no clear differences between terrestrial matter. No impacts redox on were observed. Our study shows major contributor burial indicates effective millennia lake