In:
Global Change Biology, Wiley, Vol. 28, No. 23 ( 2022-12), p. 6889-6905
Abstract:
After drought events, tree recovery depends on sufficient carbon (C) allocation to the sink organs. The present study aimed to elucidate dynamics of tree‐level C sink activity and allocation of recent photoassimilates (C new ) and stored C in c. 70‐year‐old Norway spruce ( Picea abies ) trees during a 4‐week period after drought release. We conducted a continuous, whole‐tree 13 C labeling in parallel with controlled watering after 5 years of experimental summer drought. The fate of C new to growth and CO 2 efflux was tracked along branches, stems, coarse‐ and fine roots, ectomycorrhizae and root exudates to soil CO 2 efflux after drought release. Compared with control trees, drought recovering trees showed an overall 6% lower C sink activity and 19% less allocation of C new to aboveground sinks, indicating a low priority for aboveground sinks during recovery. In contrast, fine‐root growth in recovering trees was seven times greater than that of controls. However, only half of the C used for new fine‐root growth was comprised of C new while the other half was supplied by stored C. For drought recovery of mature spruce trees, in addition to C new , stored C appears to be critical for the regeneration of the fine‐root system and the associated water uptake capacity.
Type of Medium:
Online Resource
ISSN:
1354-1013
,
1365-2486
Language:
English
Publisher:
Wiley
Publication Date:
2022
detail.hit.zdb_id:
2020313-5
SSG:
12
