Structural attributes, tree-ring growth and climate sensitivity of Pinus nigra Arn. at high altitude: common patterns of a possible treeline shift in the central Apennines (Italy)

Extreme drought events are becoming increasingly frequent and extended, particularly in Mediterranean drought-prone regions. In this sense, atmospheric oscillations patterns, such as those represented by the North Atlantic Oscillation (NAO) index and the Westerly Index (WI) have been widely proven as reliable proxies of drought trends. Here, we used the Standardized Precipitation–Evapotranspiration Index (SPEI), as a reliable indicator of drought, to investigate the drought sensitivity of tree-ring width data (TRW) from several long-lived tree species (Abies borisii-regis, Abies cilicica, Abies pinsapo, Cedrus atlantica, Cedrus libanii, Pinus nigra, Pinus heldreichii). NAO and WI relations with TRW were also investigated in order to identify potential non-stationary responses among those drought proxies. Our temporal and spatial analyses support contrasting Mediterranean dipole patterns regarding the drought sensitivity of tree growth for each tree species. The spatial assessment of NAO and WI relationships regarding SPEI and TRW showed on average stronger correlations westward with non-stationary correlations between annual WI index and TRW in all species. The results indicate that the drought variability and the inferred drought-sensitive trees species (e.g., C. atlantica) are related to the NAO and the WI, showing that TRW is a feasible proxy to long-term reconstructions of Westerly Index (WI) variability in the Western Mediterranean region. Spatial variability of drought severity suggests a complex association between NAO and WI, likely modulated by an east–west Mediterranean climate dipole.

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Influences of mature Pinus nigra plantations on the floristic-vegetational composition along an altitudinal gradient in the central Apennines, Italy

iForest - Biogeosciences and Forestry ◽

10.3832/ifor3215-013 ◽

2020 ◽

Vol 13 (1) ◽

pp. 279-285

Author(s):

M Allegrezza ◽

S Pesaresi ◽

S Ballelli ◽

G Tesei ◽

C Ottaviani

Keyword(s):

Altitudinal Gradient ◽

Pinus Nigra ◽

Central Apennines

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Climate sensitivity and resistance under pure- and mixed-stand scenarios in Lower Austria evaluated with distributed lag models and penalized regression splines for tree-ring time series

European Journal of Forest Research ◽

10.1007/s10342-019-01234-x ◽

2019 ◽

Vol 139 (2) ◽

pp. 189-211 ◽

Cited By ~ 2

Author(s):

Arne Nothdurft ◽

Markus Engel

Keyword(s):

Tree Ring ◽

Climate Sensitivity ◽

European Beech ◽

Penalized Regression ◽

Mixed Stand ◽

Regression Splines ◽

Mixed Stands ◽

Distributed Lag ◽

Distributed Lag Models ◽

Penalized Regression Splines

Abstract Penalized regression splines and distributed lag models were used to evaluate the effects of species mixing on productivity and climate-related resistance via tree-ring width measurements from sample cores. Data were collected in Lower Austria from sample plots arranged in a triplet design. Triplets were established for sessile oak [Quercus petraea (Matt.) Liebl.] and Scots pine (Pinus sylvestris L.), European beech (Fagus sylvatica L.) and Norway spruce [Picea abies (L.) H. Karst.], and European beech and European larch (Larix decidua Mill.). Mixing shortened the temporal range of time-lagged climate effects for beech, spruce, and larch, but only slightly changed the effects for oak and pine. Beech and spruce as well as beech and larch exhibited contrasting climate responses, which were consequently reversed by mixing. Single-tree productivity was reduced by between − 15% and − 28% in both the mixed oak–pine and beech–spruce stands but only slightly reduced in the mixed beech–larch stands. Measures of climate sensitivity and resistance were derived by model predictions of conditional expectations for simulated climate sequences. The relative climate sensitivity was, respectively, reduced by between − 16 and − 39 percentage points in both the beech–spruce and beech–larch mixed stands. The relative climate sensitivity of pine increased through mixing, but remained unaffected for oak. Mixing increased the resistance in both the beech–larch and the beech–spruce mixed stand. In the mixed oak–pine stand, resistance of pine was decreased and remained unchanged for oak.

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Syntaxonomy of Pinus nigra s.l. communities in the Erico-Pinetea class and their distribution in the central Apennines and Balkan province

Plant Biosystems - An International Journal Dealing with all Aspects of Plant Biology ◽

10.1080/11263504.2019.1701128 ◽

2019 ◽

Vol 154 (2) ◽

pp. 248-258

Author(s):

Edoardo Biondi ◽

Marina Allegrezza

Keyword(s):

Pinus Nigra ◽

Central Apennines

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Climate sensitivity and parameter coherency in annually resolved δ13C and δ18O from Pinus uncinata tree-ring data in the Spanish Pyrenees

Chemical Geology ◽

10.1016/j.chemgeo.2014.03.021 ◽

2014 ◽

Vol 377 ◽

pp. 12-19 ◽

Cited By ~ 23

Author(s):

Oliver Konter ◽

Steffen Holzkämper ◽

Gerhard Helle ◽

Ulf Büntgen ◽

Matthias Saurer ◽

...

Keyword(s):

Tree Ring ◽

Climate Sensitivity ◽

Pinus Uncinata ◽

Tree Ring Data ◽

Spanish Pyrenees ◽

Δ13c And Δ18o

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Regression Model for the 22-year Hale Solar Cycle Derived from High Altitude Tree-ring Data

Publications of the Astronomical Society of Australia ◽

10.1017/s1323358000019822 ◽

1994 ◽

Vol 11 (2) ◽

pp. 157-163 ◽

Cited By ~ 2

Author(s):

J. O. Murphy ◽

H. Sampson ◽

T. T. Veblen ◽

R. Villalba

Keyword(s):

Solar Cycle ◽

Regression Model ◽

High Altitude ◽

Tree Ring ◽

Magnetic Cycle ◽

Tree Ring Data ◽

Highly Correlated ◽

Successive Maximum ◽

Index Time Series ◽

Past 300 Years

AbstractInitially some simple analytical properties based on the annual Zürich relative sunspot number are established for the 22-year Hale solar magnetic cycle. Since about AD1850, successive maximum sunspot numbers in a Hale cycle are highly correlated. Also, a regression model for the reconstruction of the 22-year Hale cycle has been formulated from proxy tree-ring data, obtained from spruce trees growing at a high altitude site in White River National Forest in Colorado. Over a considerable fraction of the past 300 years to AD1986, the ring-index time series power spectrum exhibits a strong 22-year periodicity, and more recently a significant spectral peak (at the 95% confidence level) at approximately 11 years. The model shows that the greatest variation in ‘amplitude’ in the magnetic cycle occurs over the early decades of the eighteenth century, when the sample size is small. Thereafter, a nearly constant amplitude is maintained until about AD1880 when a break occurs in both phase correspondence and amplitude, extending over the next three cycles. From AD1950 the signal recovers phase with the solar cycle, with reduced but increasing amplitude.

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