Pinus pinea Pinus cembra
•Croda da Lago, 2100 m a.s.l.
•Castelvolturno, 8 m a.s.l.
•Plantation close to the seashore
•Quercus ithaburensis and Q. boissieri
•Lower Galilee, 150 m a.s.l., and
Merom Golan, 960 m a.s.l.
The retrospective analysis of xylem anatomical traits along
tree-ring series allows to get insights into growth –
environment interactions, and to inspect xylem responses
to past climate variability.
While most studies have investigated anatomical features
at the ring level (e.g. mean vessel/tracheid lumen size), we
applied anatomical analysis at the intra-ring level.
Earlywood split in 10 parts,
Latewood split in 5 parts
Intra-annual dendroanatomy can improve our understating
of climate constraint on xylem functional traits
Daniele CASTAGNERI1,4, Giovanna BATTIPAGLIA2, Elisabetta BOARETTO3, Marco CARRER4,
Patrick FONTI1, Arturo PACHECO4, Lior REGEV3, Lucrezia UNTERHOLZNER4, Georg VON ARX1
1WSL Swiss Federal Institute, Birmensdorf, Switzerland; 2University of Campania L. Vanvitelli, Caserta, Italy;
3Weizmann Institute of Science, Rehovot, Israel; 4University of Padova, Padova, Italy
Castagneri D., Battipaglia G., von Arx G., Pacheco A., Carrer M., 2018. Tree-ring anatomy and carbon isotope ratio show
both direct and legacy effects of climate on bimodal xylem formation in Pinus pinea. Tree Physiology, 38, 1098–1109
Castagneri D., Regev L., Boaretto E., Carrer M., 2017. Xylem anatomical traits reveal different strategies of two
Mediterranean oaks to cope with drought and warming. Environmental and Experimental Botany, 133, 128-138
Carrer M., Unterholzner L., Castagneri D., 2018. Wood anatomical traits highlight complex temperature influence on Pinus
cembra at high elevation in the Eastern Alps. International Journal of Biometeorology, 62, 1745–1753
4th Xylem International Meeting
Padua, 25-27 September 2019
We do not know when each cell was
formed in each ring, but we know that the
first cells in the ring were formed earlier.
Investigating cells in different position
within the ring allowed us to get
information on xylem formed in different
parts of the growing season.
Crossing these data with highly-resolved
climate data, provided information on
intra-seasonal climate influence on xylem
structure across the growing season.
STUDY AREAS AND SPECIES
First formed cells
Last formed cells
Ring split in 10 parts
Ring split in 3 parts
1st cell row, 2nd row, others
Correlations between anatomical parameters and bi-monthly and
seasonal (Nov–Apr) precipitation and temperature.
Max is the maximum vessel lumen area, Max3 is area of the three largest vessels, Dh is hydraulic
diameter, S1, S2, and S3 for Q. ithab., and R1, R2, and R3 for Q. boiss, are the maximum vessel
lumen area within each ring sector (Q. ithab) or row (Q. boiss), Num is vessel number, MRW is ring
width, Ks is xylem-specific potential hydraulic conductivity, Kr is ring specific hydraulic conductivity.
Correlations of lumen diameter in 10 earlywood (EW) and
5 latewood (LW) sectors, with daily precipitation (50-day
windows) from November of the previous year to the
current year November.
Q. ithaburensis xylem anatomical features are more
sensitive to reduced precipitation in the wet season;
those of Q. boissieri are more sensitive to high
temperature in spring.
In Q. ithaburensis, intra-seasonal patterns are scarcely
evident, probably due to smaller rings and shorter
growing season imposed by xeric site conditions.
In Q. boissieri, large early vessels are constrained by
warm conditions in early winter; small late vessels are
affected by precipitation and early spring temperature.
P. pinea tracheid lumen area is highly sensitive to
Size of the first cell rows is related to precipitation
accumulated in late winter, while the second part of
earlywood cells, and the very first cells of latewood,
are sensitive to rain in late spring.
After summer rest, we observe strong influence of
October to November rain on lumen size of tracheid
in the second part of the latewood.
Cell lumen area
Cell wall thickness
Cell lumen area
Correlations of cell lumen area and cell wall thickness
along 10 ring sectors, with daily temperature (15-day
windows) from April to September.
P. cembra tracheid lumen size and wall thickness
are both sensitive to summer temperature.
The signal occurs earlier for lumen size, reflecting
the xylogenesis phases successions (first cell
enlargement, later cell wall thickening).
The time shift of correlations from the early to the
late part of the ring, evident in both the anatomical
parameters, recalls the timing of xylem formation
across the growing season.