The current paradigm in peatland ecology is that the organic matter inputs from plant photosynthesis (e.g. moss litter) exceed that of decomposition, tipping the metabolic balance in favour of carbon (C) storage. Here, we investigated an alternative hypothesis, whereby exudates released by microalgae can actually accelerate C losses from the surface waters of northern peatlands by stimulating dissolved organic C ( When Specific ultraviolet absorbance at 254 nm (SUVA254), a proxy for aromatic content, was also significantly higher (i.e. more humic) in the mixture treatment than expected from SUVA254values in single substrate treatments. Accelerated decomposition in the presence of algal These results present an alternative energy pathway for heterotrophic consumers to breakdown organic matter in northern peatlands. Since decomposition in northern peatlands is often limited by the availability of labile organic matter, this mechanism could become increasingly important as a pathway for decomposition in the surface waters of northern peatlands where algae are expected to be more abundant in conditions associated with ongoing climate change.
Despite the large contribution of rangeland and pasture to global soil organic carbon (
- NSF-PAR ID:
- 10053638
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Global Change Biology
- Volume:
- 24
- Issue:
- 7
- ISSN:
- 1354-1013
- Page Range / eLocation ID:
- p. 2997-3009
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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