Leaf lifespan and lifetime carbon balance of individual leaves in a stand of an annual herb, Xanthium canadense
Leaf lifespan in response to resource availability has been documented in many studies, but it still remains uncertain what determines the timing of leaf shedding. Here, we evaluate the lifetime carbon (C) balance of a leaf in a canopy as influenced by nitrogen (N) availability. Stands of Xanthium c...
Veröffentlicht in: | The New phytologist. - 1979. - 172(2006), 1 vom: 01., Seite 104-16 |
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1. Verfasser: | |
Weitere Verfasser: | , |
Format: | Aufsatz |
Sprache: | English |
Veröffentlicht: |
2006
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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 Nitrogen N762921K75 |
Zusammenfassung: | Leaf lifespan in response to resource availability has been documented in many studies, but it still remains uncertain what determines the timing of leaf shedding. Here, we evaluate the lifetime carbon (C) balance of a leaf in a canopy as influenced by nitrogen (N) availability. Stands of Xanthium canadense were established with high-nitrogen (HN) and low-nitrogen (LN) treatments and temporal changes of C gain of individual leaves were investigated with a canopy photosynthesis model. Daily C gain of a leaf was maximal early in its development and subsequently declined. Daily C gain at shedding was nearly zero in HN, while it was still positive in LN. Sensitivity analyses showed that the decline in the daily C gain resulted primarily from the reduction in light level in HN and by the reduction in leaf N in LN. Smaller leaf size in LN than in HN led to higher light levels in the canopy, which helped leaves of the LN stand maintain for a longer period. These results suggest that the mechanism by which leaf lifespan is determined changes depending on the availability of the resource that is most limiting to plant growth |
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Beschreibung: | Date Completed 26.10.2006 Date Revised 30.09.2020 published: Print Citation Status MEDLINE |
ISSN: | 1469-8137 |