Stored carbon partly fuels fine-root respiration but is not used for production of new fine roots
No claim to original US government works. New Phytologist © 2013 New Phytologist Trust.
| Veröffentlicht in: | The New phytologist. - 1979. - 199(2013), 2 vom: 03. Juli, Seite 420-430 |
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| 1. Verfasser: | |
| Weitere Verfasser: | , , , |
| Format: | Online-Aufsatz |
| Sprache: | English |
| Veröffentlicht: |
2013
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| Zugriff auf das übergeordnete Werk: | The New phytologist |
| Schlagworte: | Journal Article Research Support, U.S. Gov't, Non-P.H.S. Carbon Isotopes Carbon Dioxide 142M471B3J Carbon 7440-44-0 |
| Zusammenfassung: | No claim to original US government works. New Phytologist © 2013 New Phytologist Trust. The relative use of new photosynthate compared to stored carbon (C) for the production and maintenance of fine roots, and the rate of C turnover in heterogeneous fine-root populations, are poorly understood. We followed the relaxation of a (13)C tracer in fine roots in a Liquidambar styraciflua plantation at the conclusion of a free-air CO(2) enrichment experiment. Goals included quantifying the relative fractions of new photosynthate vs stored C used in root growth and root respiration, as well as the turnover rate of fine-root C fixed during [CO(2)] fumigation. New fine-root growth was largely from recent photosynthate, while nearly one-quarter of respired C was from a storage pool. Changes in the isotopic composition of the fine-root population over two full growing seasons indicated heterogeneous C pools; < 10% of root C had a residence time < 3 months, while a majority of root C had a residence time > 2 yr. Compared to a one-pool model, a two-pool model for C turnover in fine roots (with 5 and 0.37 yr(-1) turnover times) doubles the fine-root contribution to forest NPP (9-13%) and supports the 50% root-to-soil transfer rate often used in models |
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| Beschreibung: | Date Completed 15.01.2014 Date Revised 18.04.2021 published: Print-Electronic Citation Status MEDLINE |
| ISSN: | 1469-8137 |
| DOI: | 10.1111/nph.12290 |