The impacts of repeated drought on the aboveground primary growth of Pinus halepensis Mill. and Quercus ilex L. in mediterranean France
2010 The impacts of repeated drought on the aboveground primary growth of Pinus halepensis Mill., and Quercus ilex L., in Mediterranean France. DIDIER Cody (USA) email@example.com
Organisation: University of Poitiers, Poitiers (FR) - CEMAGREF, Aix en Provence (FR) Supervisor : Michel Vennetier & François Girard (Cemagref)
Summary: The Mediterranean basin is forecast to experience warming above the global average with concurrent decreases in precipitation and increases in the frequency of severe drought and heat waves over the course of the 21st century, but the impact of severe and/or repeated drought on the aboveground primary growth of Mediterranean forest trees is not well understood. Architectural analysis of Aleppo pine and holm oak, two widely distributed western Mediterranean tree species, was carried out for trees along an elevation transect. Aleppo pine primary growth was greatly reduced following the 2003 heat wave and four subsequent years of drought. Recovery of most architectural variables was seen after two years without drought. Severe drought in 2007 resulted in minimal primary growth of holm oak, but leaf development recovered the year after drought and recovery appeared to be related to well-timed precipitation after bud burst. Climatic conditions at the low and high sites of the elevation transect appear to impose limits to primary growth and post-drought recovery. The species likely to be favored could not be determined, but it is clear that the expected climate change for the Mediterranean basin will greatly reduce primary growth with implications for Aleppo pine-holm oak forest ecosystem functioning.