CORDIS OpenAire Sygma Bielefeld Academic Search Engine (BASE) HAL-INSU HAL-IRD HAL-UPMC Horizon / Pleins textes Crossref Microsoft Academic Graph Europe PubMed Central HAL INRAE UnpayWall BOA - Bicocca Open Archive Archivio Istituzionale della Ricerca dell'Università degli Studi di Milano OpenAPC Global Initiative PubMed Central European Union Open Data Portal https://air.unimi.it/bitstream/2434/851691/2/khedim%202021%20submitted.pdf https://air.unimi.it/bitstream/2434/851691/3/khedim%202021%20Global%20Change%20Biol.pdf https://boa.unimib.it/bitstream/10281/300214/2/10281-300214_VoR.pdf https://onlinelibrary.wiley.com/doi/pdf/10.1111/gcb.15496 https://doi.org/10.1111/gcb.15496 Global Change Biology Open Access 2020-12-20 2021-06-21 2021-01-24 2021-01-29 Abstract<p>Since the last glacial maximum, soil formation related to ice￢ﾀﾐcover shrinkage has been one major sink of carbon accumulating as soil organic matter (SOM), a phenomenon accelerated by the ongoing global warming. In recently deglacierized forelands, processes of SOM accumulation, including those that control carbon and nitrogen sequestration rates and biogeochemical stability of newly sequestered carbon, remain poorly understood. Here, we investigate the build￢ﾀﾐup of SOM during the initial stages (up to 410ￂﾠyears) of topsoil development in 10 glacier forelands distributed on four continents. We test whether the net accumulation of SOM on glacier forelands (i) depends on the time since deglacierization and local climatic conditions (temperature and precipitation); (ii) is accompanied by a decrease in its stability and (iii) is mostly due to an increasing contribution of organic matter from plant origin. We measured total SOM concentration (carbon, nitrogen), its relative hydrogen/oxygen enrichment, stable isotopic (13C, 15N) and carbon functional groups (C￢ﾀﾐH, C=O, C=C) compositions, and its distribution in carbon pools of different thermal stability. We show that SOM content increases with time and is faster on forelands experiencing warmer climates. The build￢ﾀﾐup of SOM pools shows consistent trends across the studied soil chronosequences. During the first decades of soil development, the low amount of SOM is dominated by a thermally stable carbon pool with a small and highly thermolabile pool. The stability of SOM decreases with soil age at all sites, indicating that SOM storage is dominated by the accumulation of labile SOM during the first centuries of soil development, and suggesting plant carbon inputs to soil (SOM depleted in nitrogen, enriched in hydrogen and in aromatic carbon). Our findings highlight the potential vulnerability of SOM stocks from proglacial areas to decomposition and suggest that their durability largely depends on the relative contribution of carbon inputs from plants.</p> [SDV.BID.SPT]Life Sciences [q-bio]/Biodiversity/Systematics 550 Nitrogen Chronosequence 551 01 natural sciences [SDV.BV.BOT] Life Sciences [q-bio]/Vegetal Biology/Botanics Soil soil organic matter carbon stability; chronosequence; climate sensitivity; soil organic matter; topsoil development; Carbon; Nitrogen; Temperature; Ice Cover; Soil [SDV.BID.SPT] Life Sciences [q-bio]/Biodiversity/Systematics, Phylogenetics and taxonomy [SDV.EE.ECO] Life Sciences [q-bio]/Ecology, environment/Ecosystems Ice Cover topsoil development Carbon stability 0105 earth and related environmental sciences 2. Zero hunger Soil organic matter Temperature Phylogenetics and taxonomy 04 agricultural and veterinary sciences [SDV.BV.BOT]Life Sciences [q-bio]/Vegetal Biology/Botanics 15. Life on land Climate sensitivity Primary Research Articles Carbon chronosequence [SDE.BE] Environmental Sciences/Biodiversity and Ecology 13. Climate action [SDV.EE.ECO]Life Sciences [q-bio]/Ecology [SDE]Environmental Sciences Topsoil development climate sensitivity carbon stability; chronosequence; climate sensitivity; soil organic matter; topsoil development; 0401 agriculture, forestry, and fisheries [SDE.BE]Environmental Sciences/Biodiversity and Ecology environment/Ecosystems carbon stability Sophie Cauvy-Fraunié, Gentile Francesco Ficetola, Gentile Francesco Ficetola, Roberto Sergio Azzoni, Silvio Marta, Roberto Ambrosini, Lauric Cécillon, Lauric Cécillon, Ludovic Gielly, Jérôme Poulenard, Marco Caccianiga, Andrea Franzetti, Norine Khedim, Pierre Barré, Levan Tielidze, Antoine Rabatel, Chiara Compostella, François Baudin, Philippe Choler, Erwan Messager, Cédric Dentant, Fabien Anthelme, John J. Clague, 2021-01-16 journalpaper Abstract<p>Since the last glacial maximum, soil formation related to ice￢ﾀﾐcover shrinkage has been one major sink of carbon accumulating as soil organic matter (SOM), a phenomenon accelerated by the ongoing global warming. In recently deglacierized forelands, processes of SOM accumulation, including those that control carbon and nitrogen sequestration rates and biogeochemical stability of newly sequestered carbon, remain poorly understood. Here, we investigate the build￢ﾀﾐup of SOM during the initial stages (up to 410ￂﾠyears) of topsoil development in 10 glacier forelands distributed on four continents. We test whether the net accumulation of SOM on glacier forelands (i) depends on the time since deglacierization and local climatic conditions (temperature and precipitation); (ii) is accompanied by a decrease in its stability and (iii) is mostly due to an increasing contribution of organic matter from plant origin. We measured total SOM concentration (carbon, nitrogen), its relative hydrogen/oxygen enrichment, stable isotopic (13C, 15N) and carbon functional groups (C￢ﾀﾐH, C=O, C=C) compositions, and its distribution in carbon pools of different thermal stability. We show that SOM content increases with time and is faster on forelands experiencing warmer climates. The build￢ﾀﾐup of SOM pools shows consistent trends across the studied soil chronosequences. During the first decades of soil development, the low amount of SOM is dominated by a thermally stable carbon pool with a small and highly thermolabile pool. The stability of SOM decreases with soil age at all sites, indicating that SOM storage is dominated by the accumulation of labile SOM during the first centuries of soil development, and suggesting plant carbon inputs to soil (SOM depleted in nitrogen, enriched in hydrogen and in aromatic carbon). Our findings highlight the potential vulnerability of SOM stocks from proglacial areas to decomposition and suggest that their durability largely depends on the relative contribution of carbon inputs from plants.</p> Topsoil organic matter build‐up in glacier forelands around the world 10.1111/gcb.15496