Volumes 192–193, 15 July 2014, Pages 9–17
- a Southern Swedish Forest Research Centre, Swedish University of Agricultural Sciences, P.O. Box 49, SE-230 53 Alnarp, Sweden
- b Chaire industrielle CRSNG-UQAT-UQAM en aménagement forestier durable, Université du Québec en Abitibi-Témiscamingue (UQAT), 445 boul. de l’Université, Rouyn-Noranda, Québec, J9X 5E4, Canada
- c Nordens Ark, Åby säteri, 45693 Hunnebostrand, Sweden
- d Centre d’étude de la forêt, Université du Québec en Abitibi-Témiscamingue (UQAT), 445 boul. de l’Université, Rouyn-Noranda, Québec, J9X 5E4, Canada
- Received 24 September 2013, Revised 18 February 2014, Accepted 20 February 2014, Available online 19 March 2014
- Referred to by
Peer review report 2 On “Reconstruction of a 253 year-long mast record of European beech revealsits association with large scale temperature variability and no long-term trend in mast frequencies”
- Agricultural and Forest Meteorology, Volume 201, Supplement 1, January–December 2015, Pages 271-272
Peer review report 1 On “Reconstruction of a 253 year-long mast record of European beech revealsits association with large scale temperature variability and no long-term trend in mast frequencies”
- Agricultural and Forest Meteorology, Volume 201, Supplement 1, January–December 2015, Page 456
Peer review report 1 On “Reconstruction of a 253 year-long mast record of European beech revealsits association with large scale temperature variability and no long-term trend in mast frequencies”
- Agricultural and Forest Meteorology, Volume 201, Supplement 1, January–December 2015, Page 458
Highlights
- •
- We developed 253-year long record of European beech mast years.
- •
- Masting behavior is controlled by summer temperature and pressure variability.
- •
- Changes in atmospheric circulation are likely drivers of masting phenomenon.
- •
- Shorter intervals between mast years at the end of 20th century are not unique in a multi-century perspective.
Abstract
Synchronous production of large seed crops, or mast years (MYs), is a common feature of many Fagus
species, which is closely linked to the dynamics of forest ecosystems,
including regeneration of canopy trees and changes in animal population
densities. To better understand its climatic controls and check for the
presence of long-term temporal trends in MY frequencies, we
reconstructed MY record of the European beech (Fagus sylvatica
L.) for the southern Swedish province of Halland over 1753–2006. We used
superimposed epoch analysis (SEA) to relate MY (a) to summer
temperature fields over the European subcontinent and (b) to the
patterns of 500 mb geopotential heights over the 35–75°N. For the MY
reconstruction, we used newly developed regional beech ring-width
chronology (1753–2006), an available summer temperature reconstruction,
and a discontinuous historical MY record. A Monte Carlo experiment
allowed identification of the thresholds in both growth and summer
temperature anomalies, indicative of historical MYs, which were verified
by dividing data into temporally independent calibration and
verification sub-periods.
MYs were strongly
associated with both the 500 mb height anomalies and average summer
temperatures during two years preceding a MY: a mast year (t) followed a cold summer two years (t-2) prior to the mast year and a warm summer one year prior (t-1) to the mast year. During t-2
years, the geographical pattern of 500 mb height anomalies exhibited a
strong height depression in the region centered in the Northern Sea and
extending toward eastern North America and statistically significant (p < 0.05)
temperature anomalies covering predominantly southern Scandinavia (area
below 60 N) and British Isles. A year immediately preceding a mast year
(t-1) was characterized by a strong regional high pressure
anomaly centered in southern Scandinavia with significant temperature
anomalies extended mostly over southern Scandinavia and Germany.
The
long-term mean MY return interval was 6.3 years, with 50 and 90%
probabilities of MY occurrence corresponding to 6 and 15 years,
respectively. Periods with intervals significantly shorter than the
long-term mean were observed around 1820–1860 and 1990–2006 (means – 3.9
and 3.2 years, respectively). However, the difference in return
intervals between two sub-periods themselves was not significant.
Geographically
large and temporally rapid changes in atmospheric circulation among
years, responsible for summer temperature conditions in the Northern
Europe, are likely primary environmental drivers of masting phenomenon.
However, decadal and centurial variability in MY intervals is difficult
to relate directly to temperature variability, suggesting the presence
of conditions “canceling” would-be MYs. Long-term MY reconstruction
demonstrates high variability of reproductive behavior in European beech
and indicates that a period with shorter MY intervals at the end of
20th may be not unique in a multi-century perspective.
Graphical abstract
Keywords
- Dendrochronology;
- Hardwoods;
- Pressure anomalies;
- Scandinavia;
- Seeding behavior;
- Southern Sweden;
- Tree-ring reconstruction
- Corresponding
author at: Southern Swedish Forest Research Centre, Swedish University
of Agricultural Sciences, P.O. Box 49, SE-230 53 Alnarp, Sweden; Chaire
industrielle CRSNG-UQAT-UQAM en aménagement forestier durable,
Université du Québec en Abitibi-Témiscamingue (UQAT), 445 boul. de.
l’Université, Rouyn-Noranda, Québec, J9X 5E4, Canada. Tel.:
+46 40 415199; fax: +46 40 462325.
Copyright © 2014 Elsevier B.V. All rights reserved.
