S. K. Chapman and G. S. Newman, Biodiversity at the plant-soil interface: microbial abundance and 452 community structure respond to litter mixing, Oecologia, vol.162, pp.763-772, 2010.

M. Chomel, C. Fernandez, B. Mélou, and A. , Secondary metabolites of P inus 454 halepensis alter decomposer organisms and litter decomposition during afforestation of 455 abandoned agricultural zones, Journal of Ecology, vol.102, pp.411-435, 2014.

C. C. Cleveland, S. C. Reed, and A. B. Keller, Litter quality versus soil microbial community 457 controls over decomposition: a quantitative analysis, Oecologia, vol.174, pp.283-94, 2014.

P. Davet, Microbial Ecology of Soil and Plant Growth, 2004.

S. Dorn-in, R. Bassitta, and K. Schwaiger, Specific amplification of bacterial DNA by 460 optimized so-called universal bacterial primers in samples rich of plant DNA, Journal of 461 microbiological methods, vol.113, pp.50-56, 2015.

K. Felsmann, M. Baudis, and K. Gimbel, Soil Bacterial Community Structure Responses to, p.463

, Precipitation Reduction and Forest Management in Forest Ecosystems across Germany

J. L. Balcazar, PLOS ONE, vol.10, p.122539, 2015.

N. Fierer, M. A. Bradford, and R. B. Jackson, Toward an ecological classification of soil bacteria. 466, Ecology, vol.88, pp.1354-64, 2007.

O. Folin and W. A. Denis, colorimetric method for the determination of phenols (and phenol 468 derivatives) in urine, Journal of Biological Chemistry, vol.22, issue.2, pp.305-308, 1915.

C. Fortunel, E. Garnier, and R. Joffre, Leaf traits capture the effects of land use changes and 470 climate on litter decomposability of grasslands across Europe, Ecology, 2009.

N. J. Fredriksson, M. Hermansson, and B. Wilén, The choice of PCR primers has great impact on, One, vol.8, p.76431, 2013.

J. Garcia-pausas, P. Casals, and J. Romanya, Litter decomposition and faunal activity in 476

, Mediterranean forest soils: effects of N content and the moss layer, Soil Biology and 477 Biochemistry, vol.36, pp.989-97, 2004.

J. Garcia-pausas and E. Paterson, Microbial community abundance and structure are determinants 479 of soil organic matter mineralisation in the presence of labile carbon. Soil Biology and 480, Biochemistry, vol.43, pp.1705-1718, 2011.

M. O. Gessner, C. M. Swan, and C. K. Dang, Diversity meets decomposition, Trends in ecology & 482 evolution, vol.25, pp.372-80, 2010.

H. L. Gholz, D. A. Wedin, and S. M. Smitherman, Long-term dynamics of pine and hardwood 484 litter in contrasting environments: Toward a global model of decomposition, Change Biology, vol.485, 2000.

F. Giorgi and P. Lionello, Climate change projections for the Mediterranean region, Change, vol.63, pp.90-104, 2008.

N. Gressel, Y. Inbar, and A. Singer, Chemical and spectroscopic properties of leaf litter and 489 decomposed organic matter in the Carmel Range, Israel. Soil Biology and Biochemistry, vol.490, pp.23-31, 1995.

A. Guhr, W. Borken, and M. Spohn, Redistribution of soil water by a saprotrophic fungus 492 enhances carbon mineralization, Proceedings of the National Academy of Sciences, vol.493, pp.14647-51, 2015.

J. Guiot and W. Cramer, The 2015 Paris Agreement thresholds and Mediterranean
URL : https://hal.archives-ouvertes.fr/hal-01586010

S. Güsewell and M. O. Gessner, N: P ratios influence litter decomposition and colonization by fungi 497 and bacteria in microcosms, Functional Ecology, vol.23, pp.211-220, 2009.

M. Hartmann, I. Brunner, and F. Hagedorn, A decade of irrigation transforms the soil 499 microbiome of a semi arid pine forest, Molecular ecology, vol.26, pp.1190-206, 2017.

S. Hättenschwiler and H. B. Jørgensen, Carbon quality rather than stoichiometry controls litter 501 decomposition in a tropical rain forest, Journal of Ecology, vol.98, pp.754-63, 2010.

C. Hawkes, S. N. Kivlin, and J. D. Rocca,

, Global Change Biology, vol.17, pp.1637-1682, 2011.

E. Hertig and Y. Tramblay, Regional downscaling of Mediterranean droughts under past and 505 future climatic conditions, Global and Planetary Change, vol.151, pp.36-48, 2017.

A. Hodge, D. Robinson, and A. Fitter, Are microorganisms more effective than plants at competing 507 for nitrogen?, Trends in plant science, vol.5, pp.304-312, 2000.

. Ipcc, Climate Change 2013 -The Physical Science Basis, Intergovernmental Panel on, p.509

, Cambridge, 2014.

R. Kaushal, K. S. Verma, and O. P. Chaturvedi, Leaf litter decomposition and nutrient dynamics 511 in four multipurpose tree species, Range Management and Agroforestry, vol.33, pp.20-27, 2012.

A. Klindworth, E. Pruesse, and T. Schweer, Evaluation of general 16S ribosomal RNA gene 513 PCR primers for classical and next-generation sequencing-based diversity studies, Nucleic acids research, vol.514, pp.1-1, 2013.

H. Lambers, Rising CO 2 , secondary plant metabolism, plant-herbivore interactions and litter 516 24 decomposition, 517 and biosphere. Advances in vegetation science, vol.14, p.263, 1993.

G. R. Lewin, C. Carlos, and M. G. Chevrette, Evolution and ecology of Actinobacteria and their 521 bioenergy applications, Annual review of microbiology, vol.70, pp.235-54, 2016.

J. M. Limousin, S. Rambal, J. M. Ourcival, and R. Joffre, Modelling rainfall interception in a 523

, Mediterranean Quercus ilex ecosystem: lesson from a throughfall exclusion 524 experiment, Journal of Hydrology, vol.357, issue.1-2, pp.57-66, 2008.

D. Lunghini, V. M. Granito, D. Lonardo, and D. P. , Fungal diversity of saprotrophic litter fungi in 526 a Mediterranean maquis environment, Mycologia, vol.105, pp.1499-515, 2013.

S. Manzoni, J. P. Schimel, and A. Porporato, Responses of soil microbial communities to water 528 stress: Results from a meta-analysis, Ecology, 2012.

A. J. Mccarthy and S. T. Williams, Actinomycetes as agents of biodegradation in the environment: a 530 review, Gene, vol.115, pp.189-92, 1992.

A. Meisner, J. Rousk, and E. Bååth, Prolonged drought changes the bacterial growth response to 532 rewetting, Soil Biology and Biochemistry, vol.88, pp.314-336, 2015.

F. Mohammadipanah and J. Wink, Actinobacteria from arid and desert habitats: diversity and 534 biological activity, Frontiers in microbiology, vol.6, p.1541, 2016.

J. Møller, M. Miller, and A. Kjøller, Fungal-bacterial interaction on beech leaves: influence on 536 decomposition and dissolved organic carbon quality, Soil Biology and Biochemistry, vol.537, pp.367-74, 1999.

P. Morales, T. Hickler, and D. P. Rowell, Changes in European ecosystem productivity and 539 carbon balance driven by regional climate model output. Global Change Biology, 2007.

M. J. Moro and F. Domingo, Litter decomposition in four woody species in a Mediterranean 542 climate: Weight loss, N and P dynamics, Annals of Botany, 2000.

R. Ogaya and J. Peñuelas, Tree growth, mortality, and above-ground biomass accumulation in a 545 holm oak forest under a five-year experimental field drought, Plant Ecology, 2007.

C. K. Okoro, R. Brown, and A. L. Jones, Diversity of culturable actinomycetes in hyper-arid soils 548 of the Atacama Desert, Antonie van Leeuwenhoek, vol.95, pp.121-154, 2009.

E. Ormeño, V. Baldy, and C. Ballini, Effects of environmental factors and leaf chemistry on 550 leaf litter colonization by fungi in a Mediterranean shrubland, Pedobiologia, vol.50, p.1, 2006.

J. Peñuelas, M. Estiarte, and B. A. Kimball, Variety of responses of plant phenolic concentration 553 to CO 2 enrichment, Journal of Experimental Botany, 1996.

J. Peñuelas, L. Rico, and R. Ogaya, Summer season and long-term drought increase the 555 richness of bacteria and fungi in the foliar phyllosphere of Quercus ilex in a mixed 556 Mediterranean forest, Plant Biology, vol.14, pp.565-75, 2012.

S. Pfeiffer, M. Pastar, and B. Mitter, Improved group-specific primers based on the full SILVA 558 16S rRNA gene reference database, Environmental Microbiology, vol.16, pp.2389-407, 2014.

G. Rastogi, J. J. Tech, and G. L. Coaker, A PCR-based toolbox for the culture-independent

, Microbiological Methods, vol.83, pp.127-159, 2010.

A. M. Romaní, H. Fischer, and C. Mille-lindblom, Interactions of bacteria and fungi on 563 decomposing litter: Differential extracellular enzyme activities, Ecology, 2006.

M. Sagova-mareckova, M. Omelka, and L. Cermak, Microbial Communities Show Parallels at 566 Sites with Distinct Litter and Soil Characteristics, Applied and Environmental 567 Microbiology, vol.77, pp.7560-7567, 2011.

M. Santonja, V. Baldy, and C. Fernandez, Potential Shift in Plant Communities with Climate 569 Change: Outcome on Litter Decomposition and Nutrient Release in a Mediterranean Oak 570

, Forest. Ecosystems, vol.18, pp.1253-68, 2015.

M. Santonja, C. Fernandez, T. Gauquelin, and V. Baldy, Climate change effects on litter 572 decomposition: intensive drought leads to a strong decrease of litter mixture 573 interactions, Plant and Soil, vol.393, issue.1-2, pp.69-77, 2015.

M. Santonja, A. Rancon, and N. Fromin, Plant litter diversity increases microbial abundance, 575 fungal diversity, and carbon and nitrogen cycling in a Mediterranean shrubland, Soil 576 Biology and Biochemistry, 2017.

A. Saunier, E. Ormeño, and M. Havaux, Resistance of native oak to recurrent drought 578 conditions simulating predicted climatic changes in the Mediterranean region, Plant, Cell 579 & Environment, vol.41, pp.2299-312, 2018.

J. Schimel, T. C. Balser, and M. Wallenstein, Microbial stress-response physiology and its 581 implications for ecosystem function, Ecology, vol.88, pp.1386-94, 2007.

C. Sherman, M. Sternberg, and Y. Steinberger, Effects of climate change on soil respiration and 583 carbon processing in Mediterranean and semi-arid regions: An experimental approach

, European Journal of Soil Biology, 2012.

J. Six, Fungal friends against drought, Nature Climate Change, 2012.

X. C. Souto, G. Chiapusio, and F. Pellissier, Relationships between phenolics and soil 588 microorganisms in spruce forests: Significance for natural regeneration, Journal of 589 Chemical Ecology, 2000.

. St, M. G. John, K. H. Orwin, and I. A. Dickie, No "home" versus "away" effects of de-composition 591 found in a grassland-forest reciprocal litter transplant study. Soil Biology and 592, Biochemistry, vol.43, pp.1482-1489, 2011.

M. S. Strickland, C. Lauber, and N. Fierer, Testing the functional significance of microbial 594 community composition, Ecology, 2009.

M. J. Swift, O. W. Heal, and J. M. Anderson, Decomposition in terrestrial ecosystems, p.596

S. K. Tripathi and K. P. Singh, Nutrient immobilization and release patterns during plant 598 decomposition in a dry tropical bamboo savanna, India. Biology and Fertility of Soils, vol.599, 1992.

E. J. Vainio and J. Hantula, Direct analysis of wood-inhabiting fungi using denaturing gradient gel 601 electrophoresis of amplified ribosomal DNA, Mycological Research, vol.104, pp.927-963, 2000.

P. J. Van-soest and R. H. Wine, Use of detergents in the analysis of fibrous feeds: IV. Determination 603 of plant cell-wall constituents, Journal of the Association of Official Analytical Chemists, vol.604, p.28

D. Vries, F. T. Shade, and A. , Controls on soil microbial community stability under climate change, 606 Frontiers in microbiology, vol.4, p.265, 2013.

D. A. Wardle, R. D. Bardgett, and J. N. Klironomos, Ecological linkages between aboveground 608 and belowground biota, Science, 2004.

D. A. Wardle, W. H. Putten, and . Van-der, Biodiversity, ecosystem functioning and above-ground-610 below-ground linkages. Biodiversity and Ecosystem Functioning: Synthesis and 611 Perspectives, 2002.

X. Xu, P. E. Thornton, and W. M. Post, A global analysis of soil microbial biomass carbon, nitrogen 613 and phosphorus in terrestrial ecosystems, Global Ecology and Biogeography, 2013.

J. C. Yuste, J. Peñuelas, and M. Estiarte, Drought-resistant fungi control soil organic matter 616 decomposition and its response to temperature, Global Change Biology, vol.17, p.1475, 2011.

L. H. Zeglin, P. J. Bottomley, and A. Jumpponen, Altered precipitation regime affects the 619 function and composition of soil microbial communities on multiple time scales, Ecology, vol.620, pp.2334-2379, 2013.

, Table 1 -Main characteristics of the three forest sites selected for this study, MAT= Mean, vol.657

, Annual Temperature; MAP= Mean Annual Precipitation (for the study period, 2014.

, Table 2 -Initial leaf litter quality of each litter species: Quercus pubescens, Quercus ilex and 666

, One-way ANOVA was performed to test 667 differences between initial litter species. F-Ratio are indicated and P-values with the 668 respective symbols * for P < 0.05, ** for P < 0.01, and *** for P < 0.001. Different letters 669 denote significant differences among species with a>b>c, Pinus halepensis. Values are mean ± SE (n=5)

, Table 3 -ANOVA table of F-Ratio and P-values for the effects of forest sites (S), litter 674 species (L) and drought conditions (D) on the mass loss, microbial biomass (actinobacteria, 675 bacteria and fungi) and actinobacteria/ fungi (A/F) and bacteria/ fungi (B/F) ratios

, 10 gene 691 copy number g -1 litter dry mass) for each litter species at each forest site and drought 692 condition (ND = Natural drought; AD = amplified drought). One-way ANOVAs were 693 performed for differences among litter species per drought condition and forest site. F-Ratio 694 are indicated and P-values with the respective symbols * for P, p.695

. ***-for-p-&lt;, Different letters denote significant differences among litter species with 696 a>b. T-tests was performed to test the effect of drought conditions for each species at each 697 forest site. T-test are indicated and significant P-values

, At each forest site

, Supplementary Figure 2 -Rain exclusion devices in the three forest studied (a) Quercus 736 pubescens forest at O 3 HP, (b) Quercus ilex at Puéchabon and (c) Pinus halepensis at Font

, Quercus ilex and Pinus halepensis) coming from natural drought 744 (ND) were redistributed and 2) placed in the three different forests, p.745

, Quercus ilex Puéchabon and Pinus halepensis Font-Blanche forest, respectively), under 746 natural drought (ND) and amplified drought (AD) conditions