Climate change and oak growth decline: Dendroecology and stand productivity of a Turkey oak (Quercus cerris L.) old stored coppice in Central Italy

Alfredo Di Filippo , Alfredo Alessandrini , Franco Biondi , Silvia Blasi , Luigi Portoghesi , Gianluca Piovesan

We combined stem volume increment analysis with dendroecological tools to address two unresolved issues concerning oak dieback in Mediterranean areas: early detection of changes in stand growth, and identification of mechanisms for observed growth declines.* We reconstructed productivity of a stored coppice formed by Turkey oak (Quercus cerris) to test if its growth decline was linked to climatic variability, while also accounting for age-related and sociological factors.* Drought in May-June and in prior-year late summer-autumn was negatively correlated with current growth during 1974-2006. Previous November water balance was the strongest signal. Moving Correlation Functions (11 y windows) indicated that the May-June signal remained dominant until 1996, thereafter falling to non-significant values in parallel with the May-June water balance drying trend; at the same time the previous autumn correlations reached significant values. Since 1994 there was a two-year lagged response to June water balance, suggesting that, when growth declined, loss of current-year climate signals was accompanied by the emergence of previous-year ones.* Growth and productivity of deciduous oaks in Mediterranean environments is linked to late spring-early summer hydrologic balance; at both annual and decadal timescales, oak growth decline was associated with a delayed response to climate.

Mots clés: climate change; oak decline; stem analysis; stored coppice; tree-ring

Domaines: Sylviculture, foresterie

Alfredo Di Filippo, Alfredo Alessandrini, Franco Biondi, Silvia Blasi, Luigi Portoghesi, et al.. Climate change and oak growth decline: Dendroecology and stand productivity of a Turkey oak (Quercus cerris L.) old stored coppice in Central Italy. Annals of Forest Science, 2010, 67 (7), ⟨10.1051/forest/2010031⟩. ⟨hal-00883615⟩