Regional Contingencies in the Relationship between Aboveground Biomass and Litter in the Worldâ•Žs Grasslands

Abstract

Based on regional-scale studies, aboveground production and litter decomposition are thought to positively covary, because they are driven by shared biotic and climatic factors. Until now we have been unable to test whether production and decomposition are generally coupled across climatically dissimilar regions, because we lacked replicated data collected within a single vegetation type across multiple regions, obfuscating the drivers and generality of the association between production and decomposition. Furthermore, our understanding of the relationships between production and decomposition rests heavily on separate metaanalyses of each response, because no studies have simultaneously measured production and the accumulation or decomposition of litter using consistent methods at globally relevant scales. Here, we use a multi-country grassland dataset collected using a standardized protocol to show that live plant biomass (an estimate of aboveground net primary production) and litter disappearance (represented by mass loss of aboveground litter) do not strongly covary. Live biomass and litter disappearance varied at different spatial scales. There was substantial variation in live biomass among continents, sites and plots whereas among continent differences accounted for most of the variation in litter disappearance rates. Although there were strong associations among aboveground biomass, litter disappearance and climatic factors in some regions (e.g. U.S. Great Plains), these relationships were inconsistent within and among the regions represented by this study. These results highlight the importance of replication among regions and continents when characterizing the correlations between ecosystem processes and interpreting their global-scale implications for carbon flux. We must exercise caution in parameterizing litter decomposition and aboveground production in future regional and global carbon models as their relationship is complex. Disciplines Ecology and Evolutionary Biology Comments This article is from PLoS ONE 8. no. 2 (2013): e54988, doi:10.1371/journal.pone.0054988. Rights This is an open-access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication. Authors Lydia R. O'Halloran, Elizabeth T. Borer, Eric W. Seabloom, Sarah Hobbie, Andrew S. MacDougall, Elsa E. Cleland, Rebecca L. McCulley, W. Stanley Harpole, Kirsten S. Hofmockel, Wei Li, Nicole M. DeCrappeo, Chengjin Chu, Guozhen Du, Jonathan D. Bakker, Kendi F. Davies, Brett A. Melbourne, Jennifer Firn, Nicole Hagenah, Johannes M. H. Knops, John W. Morgan, John L. Orrock, Suzanne M. Prober, and Carly J. Stevens This article is available at Iowa State University Digital Repository: http://lib.dr.iastate.edu/eeob_ag_pubs/3 Regional Contingencies in the Relationship between Aboveground Biomass and Litter in the World’s Grasslands Lydia R. O’Halloran*, Elizabeth T. Borer, Eric W. Seabloom, Andrew S. MacDougall, Elsa E. Cleland, Rebecca L. McCulley, Sarah Hobbie, W. Stan Harpole, Nicole M. DeCrappeo, Chengjin Chu, Jonathan D. Bakker, Kendi F. Davies, Guozhen Du, Jennifer Firn, Nicole Hagenah, Kirsten S. Hofmockel, Johannes M. H. Knops, Wei Li, Brett A. Melbourne, John W. Morgan, John L. Orrock, Suzanne M. Prober, Carly J. Stevens 1Department of Zoology, Oregon State University, Corvallis, Oregon, United States of America, 2Department of Ecology, Evolution, and Behavior, University of Minnesota, St. Paul, Minnesota, United States of America, 3Department of Integrative Biology, University of Guelph, Guelph, Ontario, Canada, 4 Ecology, Behavior and Evolution Section, University of California San Diego, La Jolla, California, United States of America, 5Department of Plant and Soil Sciences, University of Kentucky, Lexington, Kentucky, United States of America, 6Department of Ecology, Evolution and Organismal Biology, Iowa State University, Ames, Iowa, United States of America, 7U.S. Geological Survey, Forest and Rangeland Ecosystem Science Center, Corvallis, Oregon, United States of America, 8MOE Key Laboratory of Arid and Grassland Ecology, School of Life Sciences, Lanzhou University, Lanzhou, China, 9 School of Environmental and Forest Sciences, University of Washington, Seattle, Washington, United States of America, 10Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, Colorado, United States of America, 11Queensland University of Technology, Faculty of Science and Engineering, School of Earth, Environment and Biological Sciences, Brisbane, Queensland, Australia, 12 School of Life Sciences, University of KwaZulu-Natal, Scottsville, South Africa, 13 School of Biological Sciences, University of Nebraska, Lincoln, Nebraska, United States of America, 14Department of Botany, La Trobe University, Bundoora, Victoria, Australia, 15 Zoology Department, University of Wisconsin, Madison, Wisconsin, United States of America, 16CSIRO Ecosystem Sciences, Wembley, Western Australia, Australia, 17Department of Environment, Earth and Ecosystems, The Open University, Milton Keynes, United Kingdom, 18Department of Ecology and Evolutionary Biology, Yale University, New Haven, Connecticut, United States of America, 19 Lancaster Environment Centre, Lancaster University, Lancaster, United Kingdom

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Cite this paper

@inproceedings{OHalloran2017RegionalCI, title={Regional Contingencies in the Relationship between Aboveground Biomass and Litter in the Worldâ•Žs Grasslands}, author={Lydia R. O'Halloran and Elizabeth T. Borer and Eric W. Seabloom and Sarah E Hobbie and Andrew S Macdougall}, year={2017} }