Fine-root respiration in a loblolly pine and sweetgum forest growing in elevated CO2
• The loss of carbon below-ground through respiration of fine roots may be modified by global change. Here we tested the hypothesis that a reduction in N concentration of tree fine-roots grown in an elevated atmospheric CO2 concentration would reduce maintenance respiration and that more energy wou...
| Veröffentlicht in: | The New phytologist. - 1979. - 160(2003), 3 vom: 25. Dez., Seite 511-522 |
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| 1. Verfasser: | |
| Weitere Verfasser: | , , |
| Format: | Online-Aufsatz |
| Sprache: | English |
| Veröffentlicht: |
2003
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| Zugriff auf das übergeordnete Werk: | The New phytologist |
| Schlagworte: | Journal Article free-air CO2 enrichment (FACE) growth respiration loblolly pine (Pinus taeda) maintenance respiration nitrogen uptake respiration sweetgum (Liquidambar styeaciflua) temperate forest annual fine-root respiration |
| Zusammenfassung: | • The loss of carbon below-ground through respiration of fine roots may be modified by global change. Here we tested the hypothesis that a reduction in N concentration of tree fine-roots grown in an elevated atmospheric CO2 concentration would reduce maintenance respiration and that more energy would be used for root growth and N uptake. We partitioned total fine-root respiration (RT ) between maintenance (RM ), growth (RG ), and N uptake respiration (RN ) for loblolly pine (Pinus taeda) and sweetgum (Liquidambar styraciflua) forests exposed to elevated CO2 . • A substantial increase in fine-root production contributed to a 151% increase in RG for loblolly pine in elevated CO2 . Root specific RM for pine was 24% lower under elevated CO2 but when extrapolated to the entire forest, no treatment effect could be detected. • R G (< 10%) and RN (< 3%) were small components of RM in both forests. Maintenance respiration was the vast majority of RT , and contributed 92% and 86% of these totals at the pine and sweetgum forests, respectively. • The hypothesis was rejected because the majority of fine-root respiration was used for maintenance and was not reduced by changes in root N concentration in elevated CO2 . Because of its large contribution to RT and total soil CO2 efflux, changes in RM caused by warming may greatly alter carbon losses from forests to the atmosphere |
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| Beschreibung: | Date Revised 20.04.2021 published: Print-Electronic Citation Status PubMed-not-MEDLINE |
| ISSN: | 1469-8137 |
| DOI: | 10.1046/j.1469-8137.2003.00911.x |