Publications des scientifiques de l'IRD

Zribi L., Mouillot Florent, Guibal F., Rejeb S., Rejeb M. N., Gharbi F. (2016). Deep soil conditions make mediterranean cork oak stem growth vulnerable to autumnal rainfall decline in Tunisia. Forests, 7 (10), 245 [22 p.]. ISSN 1999-4907.

Titre du document
Deep soil conditions make mediterranean cork oak stem growth vulnerable to autumnal rainfall decline in Tunisia
Année de publication
2016
Type de document
Article référencé dans le Web of Science WOS:000388670800035
Auteurs
Zribi L., Mouillot Florent, Guibal F., Rejeb S., Rejeb M. N., Gharbi F.
Source
Forests, 2016, 7 (10), 245 [22 p.] ISSN 1999-4907
Tree rings provide fruitful information on climate features driving annual forest growth through statistical correlations between annual tree growth and climate features. Indices built upon tree growth limitation by carbon sequestration (source hypothesis) or drought-driven cambial phenology (sink hypothesis) can be used to better identify underlying processes. We used both analytical frameworks on Quercus suber, a sparsely studied species due to tree ring methodological issues, and growing on a favorable sub-humid Mediterranean climate and deep soil conditions in Tunisia (North Africa). Statistical analysis revealed the major role of autumnal rainfall before the growing season on annual tree growth over the 1918-2008 time series. Using a water budget model, we were able to explain the critical role of the deep soil water refill during the wet season in affecting both the drought onset controlling growth phenology and the summer drought intensity affecting carbon assimilation. Analysis of recent climate changes in the region additionally illustrated an increase in temperatures enhancing the evaporative demand and advancing growth start, and a decline in rainfalls in autumn, two key variables driving stem growth. We concluded on the benefits of using process-based indices in dendrochronological analysis and identified the main vulnerability of this Mediterranean forest to autumnal rainfall decline, a peculiar aspect of climate change under summer-dry climates.
Plan de classement
Sciences du milieu [021] ; Etudes, transformation, conservation du milieu naturel [082]
Description Géographique
TUNISIE
Localisation
Fonds IRD [F B010068715]
Identifiant IRD
fdi:010068715
Contact