Peatlands represent large terrestrial carbon banks. Given that most peat accumulates in boreal regions, where low temperatures and water saturation preserve organic matter, the existence of peat in (sub)tropical regions remains enigmatic. Here we examined peat and plant chemistry across a latitudinal transect from the Arctic to the tropics. Near-surface low-latitude peat has lower carbohydrate and greater aromatic content than near-surface high-latitude peat, creating a reduced oxidation state and resulting recalcitrance. This recalcitrance allows peat to persist in the (sub)tropics despite warm temperatures. Because we observed similar declines in carbohydrate content with depth in high-latitude peat, our data explain recent field-scale deep peat warming experiments in which catotelm (deeper) peat remained stable despite temperature increases up to 9 °C. We suggest that high-latitude deep peat reservoirs may be stabilized in the face of climate change by their ultimately lower carbohydrate and higher aromatic composition, similar to tropical peats.
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- Authors: Hodgkins, S.B., Richardson, C.J., Dommain, R., Wang, H., Glaser, P.H., Verbeke, B., Winkler, B.R., Cobb, A.R., Rich, V.I., Missilmani, M., Flanagan, N., Ho, M., Hoyt, A.M., Harvey, C.F., Vining, S.R., Hough, M.A., Moore, T.R., Richard, P.J.H., De, La, Cruz, F.B., Toufaily, J., Hamdan, R., Cooper, W.T., Chanton, J.P.
- Author Affiliation: Department of Chemistry and Biochemistry, Florida State University, Tallahassee, FL 32306, Department of Microbiology, The Ohio State University, Columbus, OH 43210, Duke University Wetland Center, Nicholas School of the Environment, Durham, NC 27708, Institute of Earth and Environmental Science, University of Potsdam, Potsdam, 14476, Department of Anthropology, Smithsonian Institution, National Museum of Natural History, Washington, DC 20013, Department of Earth Sciences, University of Minnesota, Minneapolis, MN 55455, Department of Earth, Ocean, and Atmospheric Science, Florida State University, Tallahassee, FL 32306, Center for Environmental Sensing and Modeling-MIT Alliance for Research and Technology, 138602, Laboratory of Materials, Catalysis, Environment and Analytical Methods (MCEMA-CHAMSI), EDST and Faculty of Sciences I, Lebanese University, Campus Rafic Hariri, Beirut, Lebanon, Max Planck Institute for Biogeochemistry, Jena, 07701, Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, Department of Soil, Water and Environmental Science, University of Arizona, Tucson, AZ 85716, Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, AZ 85716, Department of Geography, McGill University, Montreal, QC H3A 0B9, Département de Géographie, Université de Montréal, Montréal, QC H2V 2B8, Department of Civil, Construction, and Environmental Engineering, North Carolina State University, Raleigh, NC 27695
- Subjects: tropics, peatlands, carbon sinks, organic matter, climate change, carbon cycle
- Publication type: Journal Article
- Source: Nature Communications 9(1): 3640
- Year: 2018
- DOI: https://doi.org/10.1038/s41467-018-06050-2
