Allocation of carbon to fine root compounds and their residence times in a boreal forest depend on root size class and season
© 2012 The Authors. New Phytologist © 2012 New Phytologist Trust.
Veröffentlicht in: | The New phytologist. - 1979. - 194(2012), 4 vom: 19. Juni, Seite 972-981 |
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1. Verfasser: | |
Weitere Verfasser: | , , , , , , , , |
Format: | Online-Aufsatz |
Sprache: | English |
Veröffentlicht: |
2012
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Zugriff auf das übergeordnete Werk: | The New phytologist |
Schlagworte: | Journal Article Research Support, Non-U.S. Gov't Carbon 7440-44-0 Starch 9005-25-8 |
Zusammenfassung: | © 2012 The Authors. New Phytologist © 2012 New Phytologist Trust. Fine roots play a key role in the forest carbon balance, but their carbon dynamics remain largely unknown. We pulse labelled 50 m(2) patches of young boreal forest by exposure to (13)CO(2) in early and late summer. Labelled photosynthates were traced into carbon compounds of < 1 and 1-3 mm diameter roots (fine roots), and into bulk tissue of these and first-order roots (root tips). Root tips were the most strongly labelled size class. Carbon allocation to all size classes was higher in late than in early summer; mean residence times (MRTs) in starch increased from 4 to 11 months. In structural compounds, MRTs were 0.8 yr in tips and 1.8 yr in fine roots. The MRT of carbon in sugars was in the range of days. Functional differences within the fine root population were indicated by carbon allocation patterns and residence times. Pronounced allocation of recent carbon and higher turnover rates in tips are associated with their role in nutrient and water acquisition. In fine roots, longer MRTs but high allocation to sugars and starch reflect their role in structural support and storage. Accounting for heterogeneity in carbon residence times will improve and most probably reduce the estimates of fine root production |
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Beschreibung: | Date Completed 05.09.2012 Date Revised 16.04.2021 published: Print-Electronic Citation Status MEDLINE |
ISSN: | 1469-8137 |
DOI: | 10.1111/j.1469-8137.2012.04120.x |