Multi-molecular tracers of terrestrial carbon transfer across the pan-Arctic: comparison of hydrolyzable components with plant wax lipids and lignin phenols ...

• Main Authors: Feng, Xiaojuan, Gustafsson, Örjan, Holmes, Robert Max, Vonk, Jorien, van Dongen, Bart, Semiletov, Igor P., Dudarev, Oleg V., Yunker, Mark Bernard, Macdonald, Robie W., Montluçon, Daniel B., Eglinton, Timothy I.
• Format: Text
• Language: English
• Published: ETH Zurich 2015
• Subjects: Arctic
• Online Access: https://dx.doi.org/10.3929/ethz-b-000103176; http://hdl.handle.net/20.500.11850/103176

Hydrolyzable organic carbon (OC) comprises a significant component of sedimentary particulate matter transferred from land into oceans via rivers. Its abundance and nature are however not well studied in Arctic river systems, and yet may represent an important pool of carbon whose fate remains unclear in the context of mobilization and related processes associated with a changing climate. Here, we examine the molecular composition and source of hydrolyzable compounds isolated from sedimentary particles derived from nine rivers across the pan-Arctic. Bound fatty acids (b-FAs), hydroxy FAs, n-alkane-α,ω-dioic acids (DAs) and phenols were the major components released upon hydrolysis of these sediments. Among them, b-FAs received considerable inputs from bacterial and/or algal sources, whereas ω-hydroxy FAs, mid-chain substituted acids, DAs, and hydrolyzable phenols were mainly derived from cutin and suberin of higher plants. We further compared the distribution and fate of suberin- and cutin-derived compounds ... : Biogeosciences, 12 ...