Climate warming alters subsoil but not topsoil carbon dynamics in alpine grassland
© 2019 John Wiley & Sons Ltd.
| Veröffentlicht in: | Global change biology. - 1999. - 25(2019), 12 vom: 02. Dez., Seite 4383-4393 |
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| Weitere Verfasser: | , , , , , , , , , , , , , , |
| Format: | Online-Aufsatz |
| Sprache: | English |
| Veröffentlicht: |
2019
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| Zugriff auf das übergeordnete Werk: | Global change biology |
| Schlagworte: | Journal Article deep soil lignin decomposition physical fraction radiocarbon soil organic carbon warming Soil Carbon 7440-44-0 |
| Zusammenfassung: | © 2019 John Wiley & Sons Ltd. Subsoil contains more than half of soil organic carbon (SOC) globally and is conventionally assumed to be relatively unresponsive to warming compared to the topsoil. Here, we show substantial changes in carbon allocation and dynamics of the subsoil but not topsoil in the Qinghai-Tibetan alpine grasslands over 5 years of warming. Specifically, warming enhanced the accumulation of newly synthesized (14 C-enriched) carbon in the subsoil slow-cycling pool (silt-clay fraction) but promoted the decomposition of plant-derived lignin in the fast-cycling pool (macroaggregates). These changes mirrored an accumulation of lipids and sugars at the expense of lignin in the warmed bulk subsoil, likely associated with shortened soil freezing period and a deepening root system. As warming is accompanied by deepening roots in a wide range of ecosystems, root-driven accrual of slow-cycling pool may represent an important and overlooked mechanism for a potential long-term carbon sink at depth. Moreover, given the contrasting sensitivity of SOC dynamics at varied depths, warming studies focusing only on surface soils may vastly misrepresent shifts in ecosystem carbon storage under climate change |
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| Beschreibung: | Date Completed 28.11.2019 Date Revised 08.01.2020 published: Print-Electronic Citation Status MEDLINE |
| ISSN: | 1365-2486 |
| DOI: | 10.1111/gcb.14823 |