Climate-driven shifts in sediment chemistry enhance methane production in northern lakes

Abstract

29Freshwater ecosystems are a major source of methane (CH4) BY 4.0 International license peer-reviewed) is the author/funder. It is made available under aThe copyright holder for this preprint (which was not . http://dx.doi.org/10.1101/161653 doi: bioRxiv preprint first posted online Jul. 10, 2017; Manuscript TemplatePage 2 of 20 composed of macrophyte litter compared to terrestrial sources (coniferous and deciduous), which 38 we link to the inhibition of methanogenesis by polyphenol leachates. Applying our estimates to 39 projected northward advances in the distribution of Typha latifolia, a widespread and dominant 40 macrophyte, we find that CH4 production could increase by at least 73% in the lake-rich Boreal 41 Shield ecozone solely due to increases in this one macrophyte species. Our results now suggest 42 that earth system models and carbon budgets should consider the effects of plant communities on 43 sediment chemistry and ultimately CH4 emissions at a global scale.