1. Impact of climatic events on cork growth and production
Carla Leite Vanda Oliveira
Helena Pereira

2. Centro de Estudos Florestais – ISA, ULisboa
146 members PhD
ForEco - Forest ecology
ForBio - Sustainable management of biotic resources, ecosystem quality and services
ForChange - Forest ecosystem management under global change
ForTec - Forest products and biorefineries
Wood knowledge and product innovation
Biorefineries and green chemistry
Cork chain and non-wood forest products
Dendroknowledge

3. Starting point
Increasing drought frequency and severity are expected in the Mediterranean regions.
Study of the sensitivity of cork growth to extreme drought events:
10 sites in Coruche (1128 cork samples)
24-year chronology ( )
Study of the effect of a drought event along cork production cycle:
3 sites in Coruche (224 cork samples)
13-year chronology ( )

4. Annual precipitation (mm)
1995
1996
1997
1998
1999
2000
2001
2002
Annual precipitation (mm)
Cork growth decreases with drought conditions

5. Dendrochronological approach
Growth ring (mm)
standardization
Growth index

6. Growth decrease in 1995, 1999 and 2005.
Cork growth recovers quickly after a year of extreme dryness once water availability is secured.

7. Drought index (SPEI) and cork growth index
Apr 7 months – Winter conditions before growing season;
Aug 4 months – Late Spring conditions of the growing season

8. Effect of a drought along the production cycle
The age of the phellogen has no effect on the response of the tree to a drought event (2005) and on its recovery.

9. Conclusions:
Cork growth decreases in 1995, 1999 and 2005 correlated with extreme drought events of , and
Cork growth rapidly recovers when drought conditions end.
Cork growth decrease is expected leading to narrower annual rings and a consequent decrease of cork thickness.
Strong signal for forest managers to water the cork oak trees and/or to enlarge the cork growing cycles of cork.

10. Thank you!
Carla Leite