Research activities : 

I am a functional ecologist, investigating the response of the functioning of terrestrial ecosystems to global change. My research activities are directed towards better understanding the responses of soil C and N cycles in relation to plant physiology, and are centered on the following themes:
- Precipitation patterns effects on interactions between plants and soil microorganisms;
- Links between ecosystem functioning and plant biodiversity: plant source water, soil C and N cycling, soil trace gas exchange

I use stable isotopes (13C 18O, 15N), microbial ecology, ecophysiology and biogeochemistry approaches.

Publications :

• Salse J, Barnard RL, Veneault-Fourrey C, Rouached H (2024) Strategies to breed crops for future environments. Trends in Plant Science 29:303-318
• Engelhardt IE, Niklaus PA, Bizouard F, Bru D, Breuil MC, Rouard N, Mounier A, Philippot L, Barnard RL (2023) . Soil Biology & Biochemistry 185:109139
• van der Plas F, Schröder-Georgi T, Weigelt A, Barry K, Meyer S, Alzate A, Barnard RL, Buchmann N, de Kroon H, Ebeling A, Eisenhauer N, Engels C, Fischer M, Gleixner G, Hildebrandt A, Koller-France E, Leimer S, Milcu A, Mommer L, Niklaus PA, Oelmann Y, Roscher C, Scherber C, Scherer-Lorenzen M, Scheu A, Schmid B, Schulze E-D, Temperton V, Tscharntke T, Voigt W, Weisser W, Wilcke W, Wirth C (2023) Reply to: Plant traits alone are good predictors of ecosystem properties when used carefully. Nature Ecology and Evolution 7:335-336
• Tixier A, Forest M, Prudent M, Durey V, Zwieniecki M, Barnard RL (2023) Root exudation of carbon and nitrogen compounds varies over the day-night cycle in pea: the role of diurnal changes in internal pools. Plant, Cell & Environment 46:962-974
• Jacques C, Salon C, Barnard RL, Vernoud V, Prudent M (2021) Drought stress memory at the plant cycle level: a review. Plants 10:1873
• Engelhardt IC, Niklaus PA, Bizouard F, Breuil MC, Rouard N, Deau F, Philippot L, Barnard RL (2021) Precipitation patterns and N availability alter plant-soil microbial C and N dynamics. Plant and Soil 466:151-163
• Teng J, Tian J, Barnard RL, Yu G, Kuzyakov Y, Zhou J (2021) Aboveground and belowground plant traits explain latitudinal patterns in topsoil fungal communities from tropical to cold temperate forests. Frontiers in Microbiology 12:633751
• Yang L, Barnard RL, Kuzyakov Y, Tian J (2021) Bacterial communities drive the resistance of soil multifunctionality to land-use change . European Journal of Soil Biology 104:103313
• van der Plas F, Schröder-Georgi T, Weigelt A, Barry K, Meyer S, Alzate A, Barnard RL, Buchmann N, de Kroon H, Ebeling A, Eisenhauer N, Engels C, Fischer M, Gleixner G, Hildebrandt A, Koller-France E, Leimer S, Milcu A, Mommer L, Niklaus PA, Oelmann Y, Roscher C, Scherber C, Scherer-Lorenzen M, Scheu A, Schmid B, Schulze E-D, Temperton V, Tscharntke T, Voigt W, Weisser W, Wilcke W, Wirth C (2020) Plant traits are poor predictors of long-term ecosystem functioning. Nature Ecology and Evolution 4:1602-1611
• Barnard RL, Blazewicz SJ, Firestone MK (2020) Rewetting of soil: Revisiting the origin of soil CO2 emissions. Soil Biology & Biochemistry 147:107819
• Engelhardt IC, Blazewicz SJ, Barnard RL (2019) Effects of contrasting precipitation patterns on the trajectory of actively growing and inactive microbial communities after rewetting. Soil Biology & Biochemistry 134:172-174
• El Azhari N, Dermou E, Barnard RL, Storck V, Tourna M, Beguet J, Karas PA, Lucini L, Rouard N, Botteri L, Trevisan M, Karpouzas DG, Martin-Laurent F (2018) The dissipation and microbial ecotoxicity of tebuconazole and its transformation products in soil under standard laboratory and simulated winter conditions. Science of the Total Environment 637-638:892-906
• Engelhardt IC, Welty A, Blazewicz SJ, Bru D, Rouard N, Breuil MC, Gessler A, Galiano L, Miranda JC, Spor A, Barnard RL (2018) Depth matters: Effects of precipitation regime on soil microbial activity upon rewetting of a plant-soil system. The ISME Journal 12:1061-1071
• Weisser WW, Roscher C, Meyer S, Ebeling A, Luo G, Beßler H, Barnard RL, Buchmann N, Buscot F, Engels C, Fischer C, Fischer M, Gessler A, Gleixner G, Halle S, Hildebrandt A, Hillebrand H, de Kroon H, Lange M, Leimer S, Le Roux X, Milcu A, Mommert L, Pascal Niklaus P, Oelmann Y, Proulx R, Roy J, Scherber C, Scherer-Lorenzen M, Scheu S, Tscharntke T, Wachendorf M, Wagg C, Weigelt A, Wilcke W, Wirth C, Schulze ED, Schmid B, Eisenhauer N (2017) Biodiversity effects on ecosystem functioning in a 15-year grassland experiment: patterns, mechanisms, and open questions. Basic and Applied Ecology 23:1-73 [Highly Cited Paper – Web of Science]
• Calderón K, Spor A, Breuil MC, Bru D, Bizouard F, Violle C, Barnard RL, Philippot L (2017) Effectiveness of ecological rescue for altered soil microbial communities and functions. The ISME Journal 11:272-283
• Niklaus PA, Le Roux X, Poly F, Buchmann N, Scherer-Lorenzen M, Weigelt A, Barnard RL (2016) Plant species diversity affects soil-atmosphere fluxes of methane and nitrous oxide. Oecologia 181:919-930
• Salmon, Y, Buchmann N, Barnard RL (2016) Effects of ontogeny on δ13C of plant- and soil-respired CO2 and on respiratory carbon fractionation in C3 herbaceous species. PLoS One 11(3):e0151583
• Strecker T, Barnard RL, Niklaus PA, Scherer-Lorenzen M, Scheu S, Weigelt A, Eisenhauer N (2015) Effects of plant diversity, functional group composition, and fertilization on soil microbial properties in experimental grassland. PLoS One 10(5):e0125678
• Barnard RL, Osborne CA, Firestone MK (2015) Changing precipitation pattern alters soil microbial community response to wet-up under a Mediterranean-type climate. The ISME Journal 9:947-957
• Salmon Y, Barnard RL, Buchmann N (2014) Physiological controls of the isotopic time lag between leaf assimilation and soil CO2 efflux. Functional Plant Biology 41:850-859
• Shrestha J, Niklaus PA, Pasquale N, Huber B, Barnard RL, Frossard E, Schleppi P, Tockner K, Luster J (2014) Flood pulses control soil nitrogen cycling in a dynamic river floodplain. Geoderma 228-229:14-24
• Barnard RL, Osborne CA, Firestone MK (2013) Responses of soil bacterial and fungal communities to extreme desiccation and rewetting. The ISME Journal 7:2229-2241 [Highly Cited Paper – Web of Science]
• Blazewicz SJ, Barnard RL, Daly RA, Firestone MK (2013) Evaluating rRNA as an indicator of microbial activity in environmental communities: limitations and uses. The ISME Journal 7:2061-2068 [Highly Cited Paper – Web of Science]
• Le Roux X, Schmid B, Poly F, Barnard RL, Niklaus PA, Guillaumaud N, Habekost M, Oelmann Y, Philippot L, Salles J, Schloter M, Steinbeiss S, Weigelt A. (2013) Soil environmental conditions and microbial build-up mediate the effect of plant diversity on soil nitrifying and denitrifying enzyme activities in temperate grasslands. PLoS One 8(4):e61069
• Allan E, Weisser WW, Fischer M, Schulze E-D, Weigelt A, Roscher C, Baade J, Barnard RL, Bessler H, Buchmann N, Ebeling A, Eisenhauer N, Engels C, Fergus AJF, Gleixner G, Gubsch M, Halle S, Klein AM, Kertscher I, Kuu A, Lange M, Le Roux X, Meyer S,  Migunova VD, Milcu A, Niklaus PA, Oelmann Y, Pašalić E, Petermann JS, Poly F, Rottstock T, Sabais A, Scherber C, Scherer-Lorenzen M, Scheu S, Steinbeiss S, Schwichtenberg G, Temperton V, Tscharntke T, Voigt W, Wilcke W, Wirth C, Schmid B. (2013) A comparison of the strength of biodiversity effects across multiple functions. Oecologia 173:223-237
• Hartmann A, Barnard RL, Marhan S, Niklaus PA. (2013) Effects of drought and N-fertilization on N cycling in two grassland soils. Oecologia 171:705-717
• Shrestha J, Niklaus PA, Frossard E, Samaritani E, Huber B, Barnard RL, Schleppi P, Tockner K, Luster J (2012) Soil nitrogen dynamics in a river floodplain mosaic. Journal of Environmental Quality 41:2033-2045
• Niboyet A, Brown JR, Dijkstra P, Blankinship JC, Leadley PW, Le Roux X, Barthes L, Barnard RL, Field CB, Hungate BA (2011) Global change could amplify fire effects on soil greenhouse gas emissions. PloS One 6(6):e20105
• Lendenmann M, Thonar C, Barnard RL, Salmon Y, Werner RA, Frossard E, Jansa J (2011) Symbiont identity matters: Carbon and phosphorus fluxes between Medicago truncatula and different arbuscular mycorrhizal fungi. Mycorrhiza 21:689-702
• Salmon Y, Barnard RL, Buchmann N (2011) Ontogeny and gas exchange mediate the carbon isotopic signature of herbaceous plants. Plant Cell and Environment 34:465-479
• Proulx R, Wirth C, Voigt W, Weigelt A, Roscher C, Attinger S, Baade J, Barnard RL, Buchmann N, Buscot F, Eisenhauer N, Fischer M, Gleixner G, Halle S, Hildebrandt A, Kowalski E, Kuu A, Lange M, Milcu A, Niklaus PA, Oelmann Y, Rosenkranz S, Sabais A, Scherber C, Scherer-Lorenzen M, Scheu S, Schulze E-D, Schumacher J, Schwichtenberg G, Soussana J-F, Temperton VM, Weisser WW, Wilcke W, Schmid B (2010) Diversity promotes temporal stability across levels of ecosystem organization in experimental grasslands. PLoS One 5(10):e13382
• Rühr NK, Offerman C, Gessler A, Winkler BJ, Ferrio JP, Buchmann N, Barnard RL (2009) Effects of drought on allocation of recent carbon: From beech leaves to soil respiration. New Phytologist 184:950-961
• Gessler A, Brandes E, Buchmann N, Helle G, Rennenberg H, Barnard RL (2009) Tracing carbon and oxygen isotope signals from newly assimilated sugars in the leaves to the tree ring archive. Plant Cell and Environment 32:780-795
• Holst J, Barnard R, Brandes E, Buchmann N, Gessler A, Jaeger L (2008) Impacts of summer water limitation on the carbon balance of a Scots pine forest in the southern upper Rhine plain. Agricultural and Forest Meteorology 148:1815-1826
• Kodama N, Barnard RL, Salmon Y, Weston C, Ferrio JP, Holst J, Werner RA, Saurer M, Rennenberg H, Buchmann N, Gessler A (2008) Temporal dynamics of the carbon isotope composition in a Pinus sylvestris stand – from newly assimilated organic carbon to respired CO2. Oecologia 156:737-750
• Barnard RL, Salmon Y, Kodama N, Sörgel K, Holst J, Rennenberg H, Gessler A, Buchmann N (2007) Evaporative enrichment and time-lags between δ18O of leaf water and organic pools in a pine stand. Plant, Cell and Environment 30:539-550
• Barnard RL, de Bello F, Gilgen AK, Buchmann N (2006) The δ18O of root collar water best reflects source water δ18O in different types of herbaceous species. Rapid Communications in Mass Spectrometry 20:3799-3802
• Barnard R, Le Roux X, Hungate BA, Cleland EE, Blankinship JC, Barthes L, Leadley PW (2006) Several components of global change alter nitrifying and denitrifying activities in an annual grassland. Functional Ecology 20:557-564
• Barnard R, Barthes L, Leadley PW (2006) Short-term uptake of 15N by a grass and soil micro-organisms after long-term exposure to elevated CO2. Plant and Soil 280:91-99
• Barnard R, Leadley PW, Lensi R, Barthes L (2005) Plant, soil microbial and soil inorganic nitrogen responses to elevated CO2: a study in microcosms of Holcus lanatus. Acta Oecologica 27:171-178
• Barnard R, Leadley PW, Hungate BA (2005) Global change, nitrification and denitrification: a review. Global Biogeochemical Cycles 19:GB1007
• Barnard R, Barthes L, Le Roux X, Leadley PW (2004) Dynamics of nitrifying activities, denitrifying activities and nitrogen in grassland mesocosms as altered by elevated CO2. New Phytologist 162:365-376
• Barnard R, Barthes L, Le Roux X, Harmens H, Raschi A, Soussana JF, Winkler B, Leadley PW (2004) Atmospheric CO2 elevation has little effect on nitrifying and denitrifying enzyme activity in European grasslands. Global Change Biology 10:488-497

Key words :

Ecologie végétale, écologie du sol, changements globaux, cycle de l’azote du sol, biodiversité, isotopes stables