R. Andersen, L. Rocherfort, and M. Poulin, Peat, Water and Plant Tissue Chemistry Monitoring: A Seven-Year Case-Study in a Restored Peatland, Wetlands, vol.188, issue.1, pp.159-170, 2010.
DOI : 10.1007/s13157-009-0015-0

R. Bardgett and D. Wardle, Aboveground -Belowground Linkages, Biotic interactions, Ecosystem processes, and Global Change, Oxford Series In Ecology and Evolution, 2010.

R. Bardgett, C. Freeman, and N. Ostle, Microbial contributions to climate change through carbon cycle feedbacks, The ISME Journal, vol.71, issue.8, pp.805-814, 2008.
DOI : 10.1038/ismej.2008.58

F. Berendse, N. Van-breemen, H. Rydin, A. Buttler, and M. Heijmans, Raised atmospheric CO2 levels and increased N deposition cause shifts in plant species composition and production in Sphagnum bogs, Global Change Biology, vol.46, issue.5, pp.591-598, 2001.
DOI : 10.1016/0038-0717(94)00183-2

A. Breeuwer, M. Heijmans, M. Gleichman, B. Robroek, and F. Berendse, Response of Sphagnum species mixtures to increased temperature and nitrogen availability, Plant Ecology, vol.88, issue.1, pp.97-111, 2009.
DOI : 10.1007/s11258-009-9571-x

A. Breeuwer, M. Heijmans, B. Robroek, and F. Berendse, The effect of temperature on growth and competition between Sphagnum species, Oecologia, vol.128, issue.1, pp.155-167, 2008.
DOI : 10.1007/s00442-008-0963-8

M. Carlson, L. Flagstad, F. Gillet, and E. Mitchell, Community development along a proglacial chronosequence: are above-ground and below-ground community structure controlled more by biotic than abiotic factors?, Journal of Ecology, vol.84, issue.5, pp.1084-1095, 2010.
DOI : 10.1111/j.1365-2745.2010.01699.x
URL : https://hal.archives-ouvertes.fr/hal-00501619

N. Carrera, M. Barreal, P. Gallego, and M. Briones, Soil invertebrates control peatland C fluxes in response to warming, Functional Ecology, vol.321, issue.3, pp.637-648, 2009.
DOI : 10.1111/j.1365-2435.2009.01560.x

J. Cornelissen, S. Lang, N. Soudzilovskaia, and H. During, Comparative Cryptogam Ecology: A Review of Bryophyte and Lichen Traits that Drive Biogeochemistry, Annals of Botany, vol.99, issue.5, pp.987-1001, 2007.
DOI : 10.1093/aob/mcm030

E. Davidson and I. Janssens, Temperature sensitivity of soil carbon decomposition and feedbacks to climate change, Nature, vol.63, issue.7081, pp.165-173, 2006.
DOI : 10.1038/nature04514

G. De-deyn, J. Cornelissen, and R. Bardgett, Plant functional traits and soil carbon sequestration in contrasting biomes, Ecology Letters, vol.129, issue.5, pp.516-531, 2008.
DOI : 10.1039/b700021a

G. De-deyn, C. Raaijmakers, H. Zoomer, M. Berg, P. De-ruiter et al., Soil invertebrate fauna enhances grassland succession and diversity, Nature, vol.39, issue.6933, pp.711-713, 2003.
DOI : 10.1038/nature01548

F. Delarue, F. Laggoun-défarge, A. Buttler, S. Gogo, V. Jassey et al., Effects of short-term ecosystem experimental warming on water-extractable organic matter in an ombrotrophic Sphagnum peatland (Le Forbonnet, France), Organic Geochemistry, vol.42, issue.9, pp.1016-1024, 2011.
DOI : 10.1016/j.orggeochem.2011.07.005
URL : https://hal.archives-ouvertes.fr/insu-00615432

N. Dise, Peatland Response to Global Change, Science, vol.326, issue.5954, pp.810-811, 2009.
DOI : 10.1126/science.1174268

E. Dorrepaal, S. Toet, R. Van-logtestijn, E. Swart, M. Van-de-weg et al., Carbon respiration from subsurface peat accelerated by climate warming in the subarctic, Nature, vol.13, issue.7255, pp.616-679, 2009.
DOI : 10.1038/nature08216

M. Dossena, G. Yvon-durocher, J. Grey, J. Montoya, D. Perkins et al., Warming alters community size structure and ecosystem functioning, Proceedings of the Royal Society B: Biological Sciences, vol.24, issue.9, p.394, 2012.
DOI : 10.1016/j.tree.2009.03.018
URL : http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3385483

N. Eisenhauer, S. Cesarz, R. Koller, K. Worm, and P. Reich, Global change belowground: impacts of elevated CO2, nitrogen, and summer drought on soil food webs and biodiversity, Global Change Biology, vol.147, issue.105, pp.435-447, 2012.
DOI : 10.1111/j.1365-2486.2011.02555.x

B. Escofier and J. Pages, Multiple factor analysis (AFMULT package), Computational Statistics & Data Analysis, vol.18, issue.1, pp.121-140, 1994.
DOI : 10.1016/0167-9473(94)90135-X

C. Evans, D. Monteith, and D. Cooper, Long-term increases in surface water dissolved organic carbon: Observations, possible causes and environmental impacts, Environmental Pollution, vol.137, issue.1, pp.55-71, 2005.
DOI : 10.1016/j.envpol.2004.12.031

N. Fenner and C. Freeman, Drought-induced carbon loss in peatlands, Nature Geoscience, vol.27, issue.12, pp.895-900, 2011.
DOI : 10.1029/2008JG000853

N. Fenner, N. Ostle, N. Mcnamara, T. Sparks, H. Harmens et al., Elevated CO2 Effects on Peatland Plant Community Carbon Dynamics and DOC Production, Ecosystems, vol.45, issue.4, pp.635-647, 2007.
DOI : 10.1007/s10021-007-9051-x

D. Gilbert, C. Amblard, G. Bourdier, and A. Francez, The Microbial Loop at the Surface of a Peatland:Structure, Function, and Impact of Nutrient Input, Microbial Ecology, vol.35, issue.1, pp.83-93, 1998.
DOI : 10.1007/s002489900062

D. Gilbert, E. Mitchell, C. Amblard, G. Bourdier, and A. Francez, Population dynamics and food preferences of the testate amoeba Nebela tincta major-bohemica-collaris complex (Protozoa) in a Sphagnum peatland, Acta Protozoologica, vol.42, pp.99-104, 2003.

F. Gillet, M. Peter, F. Ayer, R. Butler, and S. Egli, Long-term dynamics of aboveground fungal communities in a subalpine Norway spruce forest under elevated nitrogen input, Oecologia, vol.18, issue.2, pp.499-510, 2010.
DOI : 10.1007/s00442-010-1668-3
URL : https://hal.archives-ouvertes.fr/hal-00479642

J. Gornall, I. Jonsdottir, S. Woodin, and R. Van-der-wal, Arctic mosses govern below-ground environment and ecosystem processes, Oecologia, vol.146, issue.4, pp.931-941, 2007.
DOI : 10.1007/s00442-007-0785-0

J. Grace, T. Anderson, H. Olff, and S. Scheiner, On the specification of structural equation models for ecological systems, Ecological Monographs, vol.10, issue.1, pp.67-87, 2010.
DOI : 10.2307/2527551

J. Grace, T. Anderson, M. Smith, E. Seabloom, and S. Andelman, Does species diversity limit productivity in natural grassland communities? Ecology Letters, pp.680-689, 2007.

J. Grace and J. Kelley, A Structural Equation Model Analysis Of Postfire Plant Diversity In California Shrublands, Ecological Applications, vol.16, issue.2, pp.503-514, 2006.
DOI : 10.2307/3545024

U. Gunnarsson, productivity, Journal of Bryology, vol.11, issue.20, pp.269-279, 2005.
DOI : 10.2307/2405286

P. Hájková and M. Hájek, Bryophyte and vascular plant responses to base-richness and water level gradients in Western CarpathianSphagnum-rich mires, Folia Geobotanica, vol.98, issue.3, pp.335-351, 2004.
DOI : 10.1007/BF02803207

A. Hansen, S. Jonasson, A. Michelsen, and R. Julkunen-tiitto, Long-term experimental warming, shading and nutrient addition affect the concentration of phenolic compounds in arctic-alpine deciduous and evergreen dwarf shrubs, Oecologia, vol.20, issue.1, pp.1-11, 2006.
DOI : 10.1007/s00442-005-0233-y

S. Hattenschwiler and P. Vitousek, The role of polyphenols in terrestrial ecosystem nutrient cycling. Trends in Ecology and Evolution, pp.238-243, 2000.

L. Heckmann, B. Drossel, U. Brose, and C. Guill, Interactive effects of body-size structure and adaptive foraging on food-web stability, Ecology Letters, vol.139, issue.3, pp.243-250, 2012.
DOI : 10.1111/j.1461-0248.2011.01733.x

F. Husson, J. Josse, S. Lê, and J. Mazet, FactoMineR: Factor Analysis and Data Mining with R, In. R package, vol.12, issue.1, 2009.

. Inderjit, D. Wardle, R. Karban, and R. Callaway, The ecosystem and evolutionary contexts of allelopathy, Trends in Ecology & Evolution, vol.26, issue.12, pp.655-662, 2011.
DOI : 10.1016/j.tree.2011.08.003

V. Jassey, G. Chiapusio, D. Gilbert, A. Buttler, M. Toussaint et al., Experimental climate effect on seasonal variability of polyphenol/phenoloxidase interplay along a narrow fen-bog ecological gradient in Sphagnum fallax, Global Change Biology, vol.20, issue.9, pp.2945-2957, 2011.
DOI : 10.1111/j.1365-2486.2011.02437.x
URL : https://hal.archives-ouvertes.fr/hal-00682513

V. Jassey, D. Gilbert, P. Binet, M. Toussaint, and G. Chiapusio, Effect of a temperature gradient on Sphagnum fallax and its associated living microbial communities: a study under controlled conditions, Canadian Journal of Microbiology, vol.57, issue.3, pp.226-235, 2011.
DOI : 10.1139/W10-116
URL : https://hal.archives-ouvertes.fr/hal-00682501

V. Jassey, S. Shimano, C. Dupuy, M. Toussaint, and D. Gilbert, Characterizing the Feeding Habits of the Testate Amoebae Hyalosphenia papilio and Nebela tincta along a Narrow ???Fen-Bog??? Gradient Using Digestive Vacuole Content and 13C and 15N Isotopic Analyses, Protist, vol.163, issue.3, pp.451-464, 2012.
DOI : 10.1016/j.protis.2011.07.006
URL : https://hal.archives-ouvertes.fr/hal-00682531

V. Jassey, G. Chiapusio, D. Gilbert, M. Toussaint, and P. Binet, Phenoloxidase and peroxidase activities in Sphagnum-dominated peatland in a warming climate, Soil Biology and Biochemistry, vol.46, pp.49-52, 2012.
DOI : 10.1016/j.soilbio.2011.11.011
URL : https://hal.archives-ouvertes.fr/hal-00682547

M. Jonsson and D. Wardle, Structural equation modelling reveals plant-community drivers of carbon storage in boreal forest ecosystems, Biology Letters, vol.300, issue.5621, pp.116-119, 2010.
DOI : 10.1126/science.1082709

J. Josse, J. Pages, and F. Husson, Testing the significance of the RV coefficient, Computational Statistics & Data Analysis, vol.53, issue.1, pp.82-91, 2008.
DOI : 10.1016/j.csda.2008.06.012
URL : https://hal.archives-ouvertes.fr/hal-00360535

P. Kardol, M. Bezemer, T. Van-der-putten, and W. , Temporal variation in plant-soil feedback controls succession, Ecology Letters, vol.8, issue.9, pp.1080-1088, 2006.
DOI : 10.1111/j.1461-0248.2006.00953.x

P. Kardol and D. Wardle, How understanding aboveground???belowground linkages can assist restoration ecology, Trends in Ecology & Evolution, vol.25, issue.11, pp.670-679, 2010.
DOI : 10.1016/j.tree.2010.09.001

F. Keuper, E. Dorrepaal, V. Bodegom, P. Aerts, R. Van-logtestijn et al., A Race for Space? How Sphagnum fuscum stabilizes vegetation composition during long-term climate manipulations, Global Change Biology, vol.302, issue.6, pp.2162-2171, 2011.
DOI : 10.1111/j.1365-2486.2010.02377.x
URL : https://hal.archives-ouvertes.fr/hal-00609003

S. Kim, C. Freeman, N. Fenner, and H. Kang, Functional and structural responses of bacterial and methanogen communities to 3-year warming incubation in different depths of peat mire, Applied Soil Ecology, vol.57, pp.23-30, 2012.
DOI : 10.1016/j.apsoil.2012.02.015

M. Lamentowicz, L. Lamentowicz, W. Van-der-knaap, M. Gabka, and E. Mitchell, Contrasting Species???Environment Relationships in Communities of Testate Amoebae, Bryophytes and Vascular Plants Along the Fen???Bog Gradient, Microbial Ecology, vol.18, issue.3, pp.499-510, 2010.
DOI : 10.1007/s00248-009-9617-6

S. Lang, J. Cornelissen, A. Holzer, C. Ter-braak, M. Ahrens et al., -dominated peatlands: the importance of temporal, spatial and functional scales, Journal of Ecology, vol.108, issue.2, pp.299-310, 2009.
DOI : 10.1111/j.1365-2745.2008.01472.x
URL : https://hal.archives-ouvertes.fr/jpa-00209751

P. Ledeganck, . Nijs, and L. Beyens, Plant Functional Group Diversity Promotes Soil Protist Diversity, Protist, vol.154, issue.2, pp.239-249, 2003.
DOI : 10.1078/143446103322166536

J. Limpens and F. Berendse, How litter quality affects mass loss and N loss from decomposing Sphagnum, Oikos, vol.103, issue.3, pp.537-547, 2003.
DOI : 10.1034/j.1600-0706.2003.12707.x

Z. Lindo and A. Gonzalez, The Bryosphere: An Integral and Influential Component of the Earth???s Biosphere, Ecosystems, vol.202, issue.4, pp.612-627, 2010.
DOI : 10.1007/s10021-010-9336-3

E. Mitchell, D. Borcard, A. Buttler, P. Grosvernier, D. Gilbert et al., Horizontal distribution patterns of testate amoebae (Protozoa) in a Sphagnum magellanicum carpet, Microbial Ecology, vol.39, pp.290-300, 2000.

E. Mitchell, A. Buttler, P. Grosvernier, H. Rydin, C. Albinsson et al., Relationships among testate amoebae (Protozoa), vegetation and water chemistry in five Sphagnum-dominated peatlands in Europe, New Phytologist, vol.145, issue.1, pp.95-106, 2000.
DOI : 10.1046/j.1469-8137.2000.00550.x

E. Mitchell, D. Gilbert, A. Buttler, C. Amblard, P. Grosvernier et al., Structure of Microbial Communities in Sphagnum Peatlands and Effect of Atmospheric Carbon Dioxide Enrichment, Microbial Ecology, vol.46, issue.2, pp.187-199, 2003.
DOI : 10.1007/s00248-002-0008-5

J. Oksanen, G. Blanchet, R. Kindt, P. Legendre, O. Hara et al., vegan: Community Ecology Package. R package version 1.17-1, 2010.

O. Petchey, A. Beckerman, J. Riede, and P. Warren, Size, foraging, and food web structure, Proceedings of the National Academy of Sciences of the United States of America, pp.4191-4196, 2008.
DOI : 10.1073/pnas.0710672105

O. Petchey, P. Mcphearson, T. Casey, and P. Morin, Environmental warming alters food-web structure and ecosystem function, Nature, vol.402, issue.6757, pp.69-72, 1999.
DOI : 10.1038/47023

J. Pinheiro and D. Bates, Mixed-Effects Models in S and S-PLUS, 2000.
DOI : 10.1007/978-1-4419-0318-1

L. Pomeroy, . Rr, M. Brylinsky, and P. Johnson-green, Food web connections: links and sinks, Microbial systems: new frontiers. Proc. 8th Int, pp.81-87, 2000.

M. Proctor, Seasonal and Shorter-Term Changes in Surface-Water Chemistry on Four English Ombrogenous Bogs, The Journal of Ecology, vol.82, issue.3, pp.597-610, 1994.
DOI : 10.2307/2261267

P. Robert and Y. Escoufier, Unifying tool for linear multivariate statistical-methods -rvcoefficient, Journal of the Royal Statistical Society Series C-Applied Statistics, vol.25, issue.3, pp.257-265, 1976.

R. Development and C. Team, R: A language and environment for statistical computing. R Foundation for Statistical Computing, 2010.

B. Singh, R. Bardgett, P. Smith, and D. Reay, Microorganisms and climate change: terrestrial feedbacks and mitigation options, Nature Reviews Microbiology, vol.26, issue.11, pp.779-790, 2010.
DOI : 10.1038/nrmicro2439

A. Tsyganov, R. Aerts, I. Nijs, and J. Cornelissen, Sphagnum-dwelling Testate Amoebae in Subarctic Bogs are More Sensitive to Soil Warming in the Growing Season than in Winter: the Results of Eight-year Field Climate Manipulations, Protist, vol.163, issue.3, pp.400-414, 2012.
DOI : 10.1016/j.protis.2011.07.005

M. Turetsky, The Role of Bryophytes in Carbon and Nitrogen Cycling, The Bryologist, vol.106, issue.3, pp.395-409, 2003.
DOI : 10.1639/05

N. Van-breemen, How Sphagnum bogs down other plants. Tree, pp.270-275, 1995.

P. Van-den-brink and C. Ter-braak, Principal response curves: Analysis of time-dependent multivariate responses of biological community to stress, Environmental Toxicology and Chemistry, vol.84, issue.2, pp.138-148, 1999.
DOI : 10.1002/etc.5620180207

J. Verhoeven and E. Toth, Decomposition of Carex and Sphagnum litter in fens: Effect of litter quality and inhibition by living tissue homogenates, Soil Biology and Biochemistry, vol.27, issue.3, pp.271-275, 1995.
DOI : 10.1016/0038-0717(94)00183-2

T. Veteli, W. Mattson, P. Niemela, R. Julkunen-tiitto, S. Kellomaki et al., Do Elevated Temperature and CO2 Generally Have Counteracting Effects on Phenolic Phytochemistry of Boreal Trees?, Journal of Chemical Ecology, vol.12, issue.2, pp.287-296, 2007.
DOI : 10.1007/s10886-006-9235-4

S. Ward, R. Bardgett, N. Mcnamara, J. Adamson, and N. Ostle, Long-Term Consequences of Grazing and Burning on Northern Peatland Carbon Dynamics, Ecosystems, vol.43, issue.7, pp.1069-1083, 2007.
DOI : 10.1007/s10021-007-9080-5

D. Wardle and R. Bardgett, Communities and Ecosystems: Linking the Aboveground and Belowground components, 2002.
DOI : 10.1515/9781400847297

D. Wardle, The influence of biotic interactions on soil biodiversity, Ecology Letters, vol.67, issue.7, pp.870-886, 2006.
DOI : 10.1007/s00374-003-0659-5

D. Wardle, K. Bonner, G. Barker, G. Yeates, K. Nicholson et al., PLANT REMOVALS IN PERENNIAL GRASSLAND: VEGETATION DYNAMICS, DECOMPOSERS, SOIL BIODIVERSITY, AND ECOSYSTEM PROPERTIES, Ecological Monographs, vol.69, issue.4, pp.535-568, 1999.
DOI : 10.1016/0038-0717(94)90131-7

D. Wardle, M. Jonsson, S. Bansal, R. Bardgett, G. M. Metcalfe et al., Linking vegetation change, carbon sequestration and biodiversity: insights from island ecosystems in a long-term natural experiment, Journal of Ecology, vol.85, issue.1, pp.16-30, 2012.
DOI : 10.1111/j.1365-2745.2011.01907.x

D. Wardle, R. Bardgett, W. Van-der-putten, and D. Wall, Ecological Linkages Between Aboveground and Belowground Biota, Science, vol.304, issue.5677, pp.1629-1633, 2004.
DOI : 10.1126/science.1094875

J. Weddon, G. Kowalchuck, R. Aerts, J. Van-hal, R. Van-logtestijn et al., Summer warming accelerates sub-arctic peatland nitrogen cycling without changing enzyme pools or microbial community structure, Global Change Biology, vol.71, issue.1, pp.138-150, 2012.
DOI : 10.1111/j.1365-2486.2011.02548.x

D. Wilkinson and E. Mitchell, Testate Amoebae and Nutrient Cycling with Particular Reference to Soils, Geomicrobiology Journal, vol.45, issue.6-7, pp.520-533, 2010.
DOI : 10.1016/j.cub.2006.08.018

G. Yeates and W. Foissner, Testate amoebae as predators of nematodes, Biology and Fertility of Soils, vol.16, issue.1, pp.1-7, 1995.
DOI : 10.1007/BF00307834