In summer 2018, Europe experienced a record drought, but it remains unknown how the drought affected ecosystem carbon dynamics. Using observations from 34 eddy covariance sites in different biomes across Europe, we studied the sensitivity of gross primary productivity (GPP) to environmental drivers during the summer drought of 2018 versus the reference summer of 2016. We found a greater drought-induced decline of summer GPP in grasslands (-38%) than in forests (-10%), which coincided with reduced evapotranspiration and soil water content (SWC). As compared to the 'normal year' of 2016, GPP in different ecosystems exhibited more negative sensitivity to summer air temperature (Ta) but stronger positive sensitivity to SWC during summer drought in 2018, that is, a stronger reduction of GPP with soil moisture deficit. We found larger negative effects of Ta and vapour pressure deficit (VPD) but a lower positive effect of photosynthetic photon flux density on GPP in 2018 compared to 2016, which contributed to reduced summer GPP in 2018. Our results demonstrate that high temperature-induced increases in VPD and decreases in SWC aggravated drought impacts on GPP. This article is part of the theme issue 'Impacts of the 2018 severe drought and heatwave in Europe: from site to continental scale'.

A N Severtsov Institute of Ecology and Evolution Russian Academy of Sciences Leninsky Prospect 33 119071 Moscow Russia

AgroParisTech Université de Lorraine INRAE UMR Silva 54000 Nancy France

Bioclimatology University of Goettingen Büsgenweg 2 37077 Göttingen Germany

CNR ISAFOM via Patacca 85 80040 Ercolano Italy

CSIRO Oceans and Atmosphere Aspendale 3195 Australia

DAFNAE University of Padova Viale dell'Università 16 35020 Legnaro Italy

Department Biogeochemical Integration Max Planck Institute for Biogeochemistry Hans Knöll Strasse 10 07745 Jena Germany

Department of Biological Systems Engineering University of Wisconsin Madison WI USA

Department of Environmental Systems Science ETH Zurich Universitaetstrasse 2 8092 Zurich Switzerland

Department of Forest Ecology and Management Swedish University of Agricultural Sciences Skogsmarksgränd 90183 Umeå Sweden

Department of Geography Ludwig Maximilians University Luisenstrasse 37 80333 Munich Germany

Department of Land Resources and Environmental Sciences Montana State University Bozeman MT USA

Earth and Life Institute Environmental Sciences Université catholique de Louvain via Patacca 85 80040 Ercolano Italy

Environmental Protection Agency of Aosta Valley Italy

European Commission Joint Research Centre Via E Fermi 2479 21027 Ispra Italy

Gembloux Agro Bio Tech Terra Teaching and Research Center University of Liege Gembloux Belgium

Global Change Research Institute of the Czech Academy of Sciences Bělidla 986 4a 60300 Brno Czech Republic

Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 People's Republic of China

Laboratoire des Sciences du Climat et de l'Environnement LSCE IPSL CEA CNRS UVSQ Université Paris Saclay Gif sur Yvette 91191 France

National Engineering Laboratory for Efficient Utilization of Soil and Fertilizer Resources Key Laboratory of Agricultural Environment in Universities of Shandong College of Resources and Environment Shandong Agricultural University Taian 271018 China

National Research Council Institute for Bioeconomy Rome Italy

Plants and Ecosystems University of Antwerp Universiteitsplein 1 2610 Wilrijk Belgium

Thünen Institut für Agrarklimaschutz Bundesallee 68 38116 Braunschweig Germany

Universität Rostock Landschaftsökologie und Standortkunde 18059 Rostock Germany

Zobrazit více v PubMed

Buras A, Rammig A, Zang CS. 2019. Quantifying impacts of the drought 2018 on European ecosystems in comparison to 2003. arXiv 1906.08605 (10.5194/bg-2019-286-supplement) DOI

Sousa PM, Barriopedro D, Ramos AM, García-Herrera R, Espírito-Santo F, Trigo RM. 2019. Saharan air intrusions as a relevant mechanism for Iberian heatwaves: the record breaking events of August 2018 and June 2019. Weather Clim. Extremes 26, 100224 (10.1016/j.wace.2019.100224) DOI

Van der Schrier G, Briffa K, Jones P, Osborn T.. 2006. Summer moisture variability across Europe. J. Clim. 19, 2818–2834. (10.1175/JCLI3734.1) DOI

Seneviratne SI, Lüthi D, Litschi M, Schär C. 2006. Land–atmosphere coupling and climate change in Europe. Nature 443, 205 (10.1038/nature05095) PubMed DOI

Zscheischler J, Reichstein M, Harmeling S, Rammig A, Tomelleri E, Mahecha MD. 2014. Extreme events in gross primary production: a characterization across continents. Biogeosciences 11, 2909–2924. (10.5194/bg-11-2909-2014) DOI

Humphrey V, Zscheischler J, Ciais P, Gudmundsson L, Sitch S, Seneviratne SI. 2018. Sensitivity of atmospheric CO2 growth rate to observed changes in terrestrial water storage. Nature 560, 628–631. (10.1038/s41586-018-0424-4). PubMed DOI

Reichstein M, et al. 2013. Climate extremes and the carbon cycle. Nature 500, 287–295. (10.1038/nature12350) PubMed DOI

Seneviratne SI, Corti T, Davin EL, Hirschi M, Jaeger EB, Lehner I, Orlowsky B, Teuling AJ. 2010. Investigating soil moisture–climate interactions in a changing climate: a review. Earth Sci. Rev. 99, 125–161. (10.1016/j.earscirev.2010.02.004) DOI

Bonan GB. 2008. Forests and climate change: forcings, feedbacks, and the climate benefits of forests. Science 320, 1444–1449. (10.1126/science.1155121) PubMed DOI

von Buttlar J, et al. 2018. Impacts of droughts and extreme temperature events on gross primary production and ecosystem respiration: a systematic assessment across ecosystems and climate zones. Biogeosciences 15, 1293–1318. (10.5194/bg-15-1293-2018). DOI

Konings A, Williams A, Gentine P. 2017. Sensitivity of grassland productivity to aridity controlled by stomatal and xylem regulation. Nat. Geosci. 10, 284 (10.1038/ngeo2903) DOI

Novick KA, et al. 2016. The increasing importance of atmospheric demand for ecosystem water and carbon fluxes. Nat. Clim. Change 6, 1023 (10.1038/nclimate3114) DOI

Goodrich J, Campbell D, Clearwater M, Rutledge S, Schipper L. 2015. High vapor pressure deficit constrains GPP and the light response of NEE at a Southern Hemisphere bog. Agric. For. Meteorol. 203, 54–63. (10.1016/j.agrformet.2015.01.001) DOI

Luo Y. 2007. Terrestrial carbon-cycle feedback to climate warming. Annu. Rev. Ecol. Evol. Syst. 38, 683–712. (10.1146/annurev.ecolsys.38.091206.095808) DOI

Jung M, et al. 2010. Recent decline in the global land evapotranspiration trend due to limited moisture supply. Nature 467, 951 (10.1038/nature09396) PubMed DOI

Gentine P, Green JK, Guérin M, Humphrey V, Seneviratne SI, Zhang Y, Zhou S. 2019. Coupling between the terrestrial carbon and water cycles—a review. Environ. Res. Lett. 14, 083003 (10.1088/1748-9326/ab22d6) DOI

Baldocchi DD. 2020. How eddy covariance flux measurements have contributed to our understanding of Global Change Biology. Glob. Change Biol. 26, 242–260. (10.1111/gcb.14807) PubMed DOI

Mahecha MD, et al. 2017. Detecting impacts of extreme events with ecological in situ monitoring networks. Biogeosciences 14, 4255–4277. (10.5194/bg-14-4255-2017) DOI

Drought 2018 Team and ICOS Ecosystem Thematic Centre. 2019. Drought-2018 ecosystem eddy covariance flux product in FLUXNET-archive format - release 2019–1. ICOS Carbon Portal; (10.18160/PZDK-EF78) DOI

Sabbatini S, et al. 2018. Eddy covariance raw data processing for CO2 and energy fluxes calculation at ICOS ecosystem stations. Int. Agrophys. 32, 495–515. (10.1515/intag-2017-0043) DOI

Lasslop G, Reichstein M, Papale D, Richardson AD, Arneth A, Barr A, Stoy P, Wohlfahrt G. 2010. Separation of net ecosystem exchange into assimilation and respiration using a light response curve approach: critical issues and global evaluation. Glob. Change Biol. 16, 187–208. (10.1111/j.1365-2486.2009.02041.x) DOI

Reichstein M, et al. 2005. On the separation of net ecosystem exchange into assimilation and ecosystem respiration: review and improved algorithm. Glob. Change Biol. 11, 1424–1439. (10.1111/j.1365-2486.2005.001002.x) DOI

Ionita M, Tallaksen L, Kingston D, Stagge J, Laaha G, Van Lanen H, Scholz P, Chelcea S, Haslinger K.. 2017. The European 2015 drought from a climatological perspective. Hydrol. Earth Syst. Sci. 21, 1397–1419. (10.5194/hess-21-1397-2017) DOI

Laaha G, et al. 2017. The European 2015 drought from a hydrological perspective Hydrol. Earth Syst. Sci. 21, 3001–3024. (10.5194/hess-21-3001-2017) DOI

Rita A, et al. 2020. The impact of drought spells on forests depends on site conditions: the case of 2017 summer heat wave in southern Europe. Glob. Change Biol. 26, 851–863. (10.1111/gcb.14825) PubMed DOI

Albergel C, et al. 2008. From near-surface to root-zone soil moisture using an exponential filter: an assessment of the method based on in-situ observations and model simulations. Hydrol. Earth Syst. Sci. 12, 1323–1337. (10.5194/hess-12-1323-2008) DOI

Schroeder MA, Lander J, Levine-Silverman S. 1990. Diagnosing and dealing with multicollinearity. West. J. Nurs. Res. 12, 175–187. (10.1177/019394599001200204) PubMed DOI

Monteith J. 1981. Evaporation and surface temperature. Q. J. R. Meteorol. Soc. 107, 1–27. (10.1002/qj.49710745102) DOI

Pennypacker S, Baldocchi D. 2016. Seeing the fields and forests: application of surface-layer theory and flux-tower data to calculating vegetation canopy height. Boundary Layer Meteorol. 158, 165–182. (10.1007/s10546-015-0090-0) DOI

Li CC. 1975. Path analysis—a primer. Pacific Grove, CA: Boxwood Press.

Rosseel Y. 2012. Lavaan: an R package for structural equation modeling and more. Version 0.5–12 (BETA). J. Stat. Softw. 48, 1–36. (10.18637/jss.v048.i02) DOI

Liu Y, He N, Zhu J, Xu L, Yu G, Niu S, Sun X, Wen X. 2017. Regional variation in the temperature sensitivity of soil organic matter decomposition in China's forests and grasslands. Glob. Change Biol. 23, 3393–3402. (10.1111/gcb.13613) PubMed DOI

Thomas CK, Law BE, Irvine J, Martin JG, Pettijohn JC, Davis KJ. 2009. Seasonal hydrology explains interannual and seasonal variation in carbon and water exchange in a semiarid mature ponderosa pine forest in central Oregon. J. Geophys. Res. 114, G04006 (10.1029/2009JG001010) DOI

Blackman CJ, Brodribb TJ, Jordan GJ. 2009. Leaf hydraulics and drought stress: response, recovery and survivorship in four woody temperate plant species. Plant Cell Environ. 32, 1584–1595. (10.1111/j.1365-3040.2009.02023.x) PubMed DOI

Brodribb TJ, Powers J, Cochard H, Choat B. 2020. Hanging by a thread? Forests and drought. Science 368, 261–266. (10.1126/science.aat7631) PubMed DOI

Borken W, Savage K, Davidson EA, Trumbore SE. 2006. Effects of experimental drought on soil respiration and radiocarbon efflux from a temperate forest soil. Glob. Change Biol. 12, 177–193. (10.1111/j.1365-2486.2005.001058.x) DOI

Burton AJ, Pregitzer KS, Zogg GP, Zak DR. 1998. Drought reduces root respiration in sugar maple forests. Ecol. Appl. 8, 771–778. (10.1890/1051-0761(1998)008[0771:DRRRIS]2.0.CO;2) DOI

Jassal RS, Black TA, Novak MD, Gaumont-Guay D, Nesic Z. 2008. Effect of soil water stress on soil respiration and its temperature sensitivity in an 18-year-old temperate Douglas-fir stand. Glob. Change Biol. 14, 1305–1318. (10.1111/j.1365-2486.2008.01573.x) DOI

Wen X-F, Yu G-R, Sun X-M, Li Q-K, Liu Y-F, Zhang L-M, Ren C-Y, Fu Y-L, Li Z-Q. 2006. Soil moisture effect on the temperature dependence of ecosystem respiration in a subtropical Pinus plantation of southeastern China. Agric. For. Meteorol. 137, 166–175. (10.1016/j.agrformet.2006.02.005) DOI

Koven CD, Hugelius G, Lawrence DM, Wieder WR. 2017. Higher climatological temperature sensitivity of soil carbon in cold than warm climates. Nat. Clim. Change 7, 817 (10.1038/nclimate3421) DOI

Sierra CA, Trumbore SE, Davidson EA, Vicca S, Janssens I. 2015. Sensitivity of decomposition rates of soil organic matter with respect to simultaneous changes in temperature and moisture. J. Adv. Model. Earth Syst. 7, 335–356. (10.1002/2014MS000358) DOI

Teuling AJ, et al. 2010. Contrasting response of European forest and grassland energy exchange to heatwaves. Nat. Geosci. 3, 722 (10.1038/ngeo950) DOI

Konings AG, Gentine P. 2017. Global variations in ecosystem-scale isohydricity. Glob. Change Biol. 23, 891–905. (10.1111/gcb.13389) PubMed DOI

Martínez-Vilalta J, Garcia-Forner N. 2017. Water potential regulation, stomatal behaviour and hydraulic transport under drought: deconstructing the iso/anisohydric concept. Plant Cell Environ. 40, 962–976. (10.1111/pce.12846) PubMed DOI

Sippel S, Reichstein M, Ma X, Mahecha MD, Lange H, Flach M, Frank D. 2018. Drought, heat, and the carbon cycle: a review. Curr. Clim. Change Rep. 4, 266–286. (10.1007/s40641-018-0103-4) DOI

Jentsch A, et al. 2011. Climate extremes initiate ecosystem-regulating functions while maintaining productivity. J. Ecol. 99, 689–702. (10.1111/j.1365-2745.2011.01817.x) DOI

Lu M, Zhou X, Yang Q, Li H, Luo Y, Fang C, Chen J, Yang X, Li B. 2013. Responses of ecosystem carbon cycle to experimental warming: a meta-analysis. Ecology 94, 726–738. (10.1890/12-0279.1) PubMed DOI

June T, Evans JR, Farquhar GD. 2004. A simple new equation for the reversible temperature dependence of photosynthetic electron transport: a study on soybean leaf. Funct. Plant Biol. 31, 275–283. (10.1071/FP03250) PubMed DOI

Von Caemmerer S. 2000. Biochemical models of leaf photosynthesis. Techniques in Plant Science, no. 2. Collingwood, Australia: CSIRO Publishing.

Wu J, et al. 2017. Partitioning controls on Amazon forest photosynthesis between environmental and biotic factors at hourly to interannual timescales. Glob. Change Biol. 23, 1240–1257. (10.1111/gcb.13509) PubMed DOI

Quan Q, Tian D, Luo Y, Zhang F, Crowther TW, Zhu K, Chen HY, Zhou Q, Niu S. 2019. Water scaling of ecosystem carbon cycle feedback to climate warming. Sci. Adv. 5, eaav1131 (10.1126/sciadv.aav1131) PubMed DOI PMC

Poulter B, et al. 2014. Contribution of semi-arid ecosystems to interannual variability of the global carbon cycle. Nature 509, 600 (10.1038/nature13376) PubMed DOI

Tang G, Arnone J III, Verburg P, Jasoni R, Sun L. 2015. Trends and climatic sensitivities of vegetation phenology in semiarid and arid ecosystems in the US Great Basin during 1982–2011. Biogeosciences 12, 6985–6997. (10.5194/bg-12-6985-2015) DOI

Chapin FS III, Matson PA, Vitousek P. 2011. Principles of terrestrial ecosystem ecology. Berlin, Germany: Springer Science & Business Media.

Lobell DB, Roberts MJ, Schlenker W, Braun N, Little BB, Rejesus RM, Hammer GL. 2014. Greater sensitivity to drought accompanies maize yield increase in the US Midwest. Science 344, 516–519. (10.1126/science.1251423) PubMed DOI

Zhang Y, Xiao X, Zhou S, Ciais P, McCarthy H, Luo Y. 2016. Canopy and physiological controls of GPP during drought and heat wave. Geophys. Res. Lett. 43, 3325–3333. (10.1002/2016gl068501) DOI

Richardson AD, Hollinger DY, Aber JD, Ollinger SV, Braswell BH. 2007. Environmental variation is directly responsible for short- but not long-term variation in forest-atmosphere carbon exchange. Glob. Change Biol. 13, 788–803. (10.1111/j.1365-2486.2007.01330.x) DOI

Long-term daily hydrometeorological drought indices, soil moisture, and evapotranspiration for ICOS sites

Zobrazit více v PubMed

figshare
10.6084/m9.figshare.c.5077595