Multi‐variable approach pinpoints origin of oak wood with higher precision

Abstract

Aim Spatial variations of environmental conditions translate into biogeographical patterns of tree growth. This fact is used to identify the origin of timber by means of dendroprovenancing. Yet, dendroprovenancing attempts are commonly only based on ring‐width measurements, and largely neglect additional tree–ring variables. We explore the potential of using wood anatomy as a dendroprovenancing tool, and investigate whether it increases the precision of identifying the origin of oak wood. Since different tree–ring variables hold different information on environmental conditions prevailing at specific times of the growing season—which vary between source regions—we hypothesize that their inclusion allows more precise dendroprovenancing. Location Europe, Spain. Taxon Quercus robur L., Quercus petraea (Matt.) Liebl., Quercus faginea Lam., Quercus pyrenaica Willd. Methods We sampled four oak species across Northern Spain, i.e. from the Basque country and Cantabria and—in the Basque country—from low to high elevation (topographic/latitudinal gradient). We measured multiple tree–ring variables to (a) extract complementary variables; (b) present statistical relations among them; (c) analyse region‐specific variation in their patterns based on time–series of individual trees; and (d) determine underlying climate–growth relationships. Leave‐one‐out analysis was used to test whether a combination of selected variables allowed dendroprovenancing of a randomly selected tree within the area. Results A combination of latewood width (LW) and earlywood vessel size was used to pinpoint the origin of oak wood with higher precision than ring width or LW only. Variation in LW pinpointed the wood to east and west areas, whereas variation in vessels assigned wood to locations along a latitudinal/topographic gradient. The climatic triggers behind these gradients are respectively an east–west gradient in June–July temperature and a north–south gradient in winter/spring temperatures. The leave‐one‐out analyses supported the robustness of these results. Main conclusions Integration of multiple wood–xylem anatomical variables analysed with multivariate techniques leads to higher precision in the dendroprovenancing of ring‐porous oak species.

Xylem anatomy of Robinia pseudoacacia L. and Quercus robur L. is differently affected by climate in a temperate alluvial forest

“…Warm conditions during dormancy negatively affected vessel development, mainly in Q. robur, as previously reported for several ring-porous species (Alla and Camarero 2012;Castagneri et al 2017). High winter temperature is assumed to increase cell sensitivity to auxin, resulting in earlier and faster process of vessel differentiation, which leads to the formation of smaller vessels (Aloni and Zimmermann 1983;Akhmetzyanov et al 2019). In addition, high winter temperature increases respiration rate, leading to consumption of the stored reserves on which early vessel formation relies (Gea-Izquierdo et al 2012;González-González et al 2014;Pérezde-Lis et al 2018).…”

Dendroarchaeology in Europe

“…Considering the recent advances in studies of ancient plant DNA, the field of aDNA holds a great potential for combined studies on postglacial migration and climatic adoption of tree species as well as provenancing wooden objects (Wagner et al, 2018;Saleh et al, 2021). Different fields of dendro-sciences have developed various novel approaches, for example by studying density fluctuations, earlywood/latewood ratios and variances of vessel size, allowing to extract further information on the inter-to intra-annual regimes and to combine these different parameters (e.g., Wilson et al, 2017;Mann et al, 2018;Akhmetzyanov et al, 2019;Björklund et al, 2019).…”

How Cultural Heritage Studies Based on Dendrochronology Can Be Improved through Two-Way Communication

“…For archaeological wood, processes linked to diagenesis in soils can also modify isotopic composition in the wood [97]. Apart from tree-ring width, wood anatomical properties, such as vessel size in early wood in oak trees, have been used to differentiate oak populations from different geographic regions [98]. Moreover, DNA in historical wood has also proven to be an opportunity to trace the origin of the timber [99].…”