Challenges and threats for Mediterranean forests : Le Parc Naturel Régional du Luberon, a nice example!

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1 Challenges and threats for Mediterranean forests : Le Parc Naturel Régional du Luberon, a nice example! Thierry GAUQUELIN Member of CS du Parc Institut Mediterranéen de Biodiversité et d Ecologie! Workshop on Mediterranean forest management and Natura May 2016 Parc Naturel Régional du Luberon

2 Mediterranean forests???? Above all, forests subject to mediterranean climate. Therefore, no concept of structure, biological types or functional types.

3 Mediterranean climate : Climate marked by a strong deficit of precipitation during the warm season, causing stress for the vegetation which is submitted to a dry summer period. "#$%#&'()&#! &'*+,'--!!! P<2T Dry period./*0!! Stress!!!!!!

4 1'-)(!#(!'-23!45552!!!!! A climate that was not always Mediterranean

5 Calcosol OHP (Saint Michel l Observatoire) Pubescent Oak ecosystem between 80 cm & 110 cm clayey horizon penetration of Sca/Rca down to 70 cm in formof pockets 85!7$! Rca - calcarious bedrock, compact and hard, inpenetrable by rooting systems %! :;<7'! :!! <7';=7'!! 85!7$! 655!7$! 655!7$! >>>!! 685!7$! Soils often superficials "#$%! 695!7$!

6 Concerning the structure, Evergreen and sclerophyllous but also decideous forests. Holm Oak forest Puechabon Beech forest, Gargano, Pouilles, Italy!!!!!!!!!!! Aleppo Pine forest

7 The Mediterranean region, a major hotspot of plant biodiversity 2.1 millions km2 under a Mediterranean bioclimate 10 regional hotspots of plant biodiversity 10% of vascular plants richness of the World on 1.6% of the Earth surface Europe : plant species on 9.9 millions km2 Médail F. & Quézel P., Annals of the Missouri Botanical Garden, 84, completed by Véla E. & Benhouhou S., Comptes-Rendus Biologies, 330.

8 290 tree species vs135 pour North Europa

9 On the Northern shore of the Mediterranean basin, The main trend : -Increase of forestal areas But a lot of threats!: -Climate Change -Fragmentation -New forest use demands (timber, wood fuel, recreational activities) -Invasions!!!!!!!!!!!!!!!!!!!!!!!!!!!!!Cédraie of Luberon

10 Abandonment of agricultural and pastoral lands For mediterranean area (9% of the whole french forest): 1,33 millions ha in ,17 millions ha in 1989 Increase of ha by year

11 Recolonization of restanques by Aleppo Pine

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14 Climate Change???

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16 Downy Oak : O3HP (IMBE; ECCOREV) Holm Oak : PUECHABON (CEFE) Garrigue : Massif de l Etoile (IMBE) Aleppo Pine : FontBlanche (INRA) A network of experimental observatories in French Mediterranean ecosystems

17 In the Parc du Luberon! &$'()%*'#+,-% -./01,23$)4'2,% 542#$-67',2%! *$(4167,%!

18 Downy Oak (Quercus pubescens) : More than in the Mediterranean area

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20 O3HP : Understand the Downy Oak ecosystem submitted to Climate Change STRUCTURE BIODIVERSITY FORÊT FUNCTIONING DYNAMICS

21 CDE!.'(D*#)!<'+(/+F'!

22 Litter décomposition in different species mixtures C#&(#!G#!$'00#!,/-*'*&#!HIJ" ** L5! * ** ** * ** * ** K5! * * * 85! 95! :! M! C! N! :M! :C! :N! MC! MN! CN! :MC! :MN! :CN! MCN! :MCN!.O-'+P#0!G#!-*QR&#0! Increased drought strongly decreased litter decomposition but the presence of several plant species in the litter mixtures appeared to mitigate this impact. <'+(/+F'!#(!'-2!4568!HC-'+(!'+G!</*-J!

23 Mésofauna associated to litter!!!! M/+(&/-!! ST7-)0*/+!! 8#$2'%!UV!GW*+G*X*G)0!!UV!GW*+G*X*G)0! Y&*V'QG'! 669KZ! C&/0QP$'('! 6L5L! 94--,:04-$% S+(/$/V&A/$/&%D'! 9K48! <A$%DA%-#/+'! Z99! 94[! [LL! U##-*%-#/+'! L6! 5! ;4)$-%!!!! 496[K!! U/*&!\!EO(&*QX/&#0!!!!!!!!!!=/)P#!\!C&OG'(#)&0! Drier conditions affected decomposers negatively, directly by reducing detritivorous mesofauna, but also indirectly by increasing the predation pressure on detritivorous mesofauna by predatory mesofauna Some taxa disappear completely as Neelipleona /2'0$?=$% A()4:402B4:42>+$% <4=724:42>+$% 2>+$ C,,-'>-,4($% <'+(/+F'!#(!'-2!HY#7/-/P*'3!*+!%&#%J!

24 What are the Research Challenges for future? " -Study the different biodiversity levels from the mesofauna to the mycorhizal community which play a fundamental rule in ecosystems functioning -Linking biodiversity, evolution, dynamics and functioning -Linking nature and productive systems -Linking hard sciences and humanities and social sciences and Linking forestry, agricultural and social approaches and objectives.for all this, your Workshop on old growth forests!!!! - and perhaps, linking North and South of the Mediterranean: forest structure, dynamics and threats are very different on the two shores of the Mediterranean and confrontation between these different situations is essential to understand the global evolution of Mediterranean forests!