Dataset Information

Duration of xylogenesis in black spruce lengthened between 1950 and 2010.

ABSTRACT:

Background and aims

Reconstructions have identified the 20th century as being uniquely warm in the last 1000 years. Changes in the phenology of primary meristems converged toward increases in length of the growing season. Has the phenology of secondary meristem changed during the last century, and to what extent?

Methods

Timings of wood formation in black spruce, Picea mariana, were monitored for 9 years on a weekly timescale at four sites in the boreal forest of Quebec, Canada. Models for assessing xylem phenology were defined and applied to reconstruct onset, ending and duration of xylogenesis between 1950 and 2010 using thermal thresholds on chronologies of maximum and minimum temperatures.

Key results

All sites exhibited increasing trends of both annual and May-September temperatures, with the greatest changes observed at the higher latitudes. Phenological events in spring were more affected than those occurring in autumn, with cambial resumptions occurring 0·5-0·8 d decade(-1) earlier. The duration of xylogenesis has lengthened significantly since 1950, although the models supplied wide ranges of variations, between 0·07 and 1·5 d decade(-1), respectively.

Conclusions

The estimated changes in past cambial phenology demonstrated the marked effects of the recent increase in temperature on the phenological traits of secondary meristems. In the long run, the advancement of cambial activity could modify the short time window for growth of boreal species and dramatically affect the dynamics and productivity of trees in these temperature-limited ecosystems.

SUBMITTER: Boulouf Lugo J

PROVIDER: S-EPMC3478046 | biostudies-literature | 2012 Nov

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Duration of xylogenesis in black spruce lengthened between 1950 and 2010.

Boulouf Lugo Jacqueline J Deslauriers Annie A Rossi Sergio S

Annals of botany 20121004 6

<h4>Background and aims</h4>Reconstructions have identified the 20th century as being uniquely warm in the last 1000 years. Changes in the phenology of primary meristems converged toward increases in length of the growing season. Has the phenology of secondary meristem changed during the last century, and to what extent?<h4>Methods</h4>Timings of wood formation in black spruce, Picea mariana, were monitored for 9 years on a weekly timescale at four sites in the boreal forest of Quebec, Canada. M ...[more]

PMID: 23041380

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Dataset Information

Duration of xylogenesis in black spruce lengthened between 1950 and 2010.

Background and aims

Methods

Key results

Conclusions

Publications

Duration of xylogenesis in black spruce lengthened between 1950 and 2010.

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