Global CO₂ emissions from dry inland waters share common drivers across ecosystems

Inglés. This study was made possible thanks to a large collective effort of a global researchnetwork called dryflux (www.ufz.de/dryflux). We would like to thank numerous helpersfor their assistance during field work. This research was inspired by GLEON (GlobalLake Ecological Observatory Network). This work was supported by the GermanResearch Foundation (DFG, KO1911/6-1 and GR1540/23-1) to P.S.K. and H.P.G., theSpanish Ministry of Science, Innovation and Universities (C-HYDROCHANGE,CGL2017-86788-C3-3-P and CGL2017-86788-C3-2-P) to B.O. and R.M., the SpanishGovernment (CGL2016-77487-R), the Basque Government (IT951-16), the BBVAFoundation (06417) to D.vS. and A.E., the European Research Council (FP7/2007-2013,ERC grant agreement 336642) to A.L. and R.F.M., CNPq (310033/2017-9) to A.M.A., theCarlsberg Foundation (CF16-0325) to T.R. and A.P., the Nederlandse Organisatie voorWetenschappelijk Onderzoek (NWO, Veni Grant 86312012) to S.K., the EstonianMinistry of Education and Research (IUT 21-02) and the Estonian Research Councilgrant (PUT PSG32, PUT1598) to A.L. and E-I.R., the National Research Foundation ofKorea (2017R1D1A1B06035179) to J-H.P., German Federal Ministry of Education andResearch (BMBF) CLIENT programme (grant: 2WCL1337A) and German AcademicExchange Service (DAAD, grant 57218695) to M.A.F., the Seneca Foundation (20645/JLI/18) to M.M.S.M. and M.I.A. N.C. was supported by Beatriu de Pinós grant (2016-00215), A.P. by the Ramón Areces Foundation postgraduate studies programme, R.dC.by the University of Murcia (FPU R-269/2014), E.S.O.J. by the Erasmus+ ProgrammeNON-EU 2017/2018, J.R.P. by the Coordenação de Aperfeiçoamento de Pessoal de NívelSuperior (CAPES Finance Code 001). C.M-L. by the French Agency for Biodiversity(ONEMA-AFB, Action 13, ‘Colmatage, échange snappe-rivière et processus biogéochi-miques’), R.M. by the project C-HydroChange, funded by the Spanish Agencia Estatal deInvestigación (AEI) and Fondo Europeo de Desarrollo Regional (FEDER) under thecontract FEDER-MCIU-AEI/ CGL2017-86788-C3, P.S.K. by a grant for a short‐termscientific mission within the COST Action CA15113 (SMIRES, Science and Managementof Intermittent Rivers and Ephemeral Streams, www.smires.eu) and GLEON (studenttravel grant). In memory of our esteemed colleague and friend Julia Howitt, who passed away after this paper was accepted. She was full of enthusiasm for this work and will bedeeply missed by her colleagues around the world.

Inglés. Many inland waters exhibit complete or partial desiccation, or have vanished due to globalchange, exposing sediments to the atmosphere. Yet, data on carbon dioxide (CO 2) emissionsfrom these sediments are too scarce to upscale emissions for global estimates or tounderstand their fundamental drivers. Here, we present the results of a global survey cov-ering 196 dry inland waters across diverse ecosystem types and climate zones. We show thattheir CO 2 emissions share fundamental drivers and constitute a substantial fraction of thecarbon cycled by inland waters. CO2 emissions were consistent across ecosystem types andclimate zones, with local characteristics explaining much of the variability. Accounting forsuch emissions increases global estimates of carbon emissions from inland waters by 6%(~0.12 Pg C y−1). Our results indicate that emissions from dry inland waters represent asignificant and likely increasing component of the inland waters carbon cycle.