Maria Ll. Calleja

Research Scientist​​​​


My research aims at understanding the cycling and transport of organic matter in the marine environment, in particular at deciphering its changes in quantity, quality and reactivity. I have a particular interest in identifying the imprint of biological communities and processes on the chemical composition of organic compounds and how these compounds in-turn influence microbial and phytoplankton ecology.

Research Interests

Organic matter composition and cycling, microbe-organic matter interactions and transformations, biogeochemical cycles, microbial ecology.

Selected Publications

​Effects of increase glacier discharge on phytoplankton bloom dynamics and pelagic geochemistry in a high Arctic fjord. Calleja, M. Ll., Kerhervé P., Bourgeois S., Kędra M. Leynaert A. Devred E. and Morata N. Progress in Oceanography. 159: 195-210, DOI:10.1016/j.pocean.2017.07.005, (2017).
Aeolian transport of seagrass (Posidonia oceanica) beach-cast to terrestrial systems.  M.A. Jiménez, Beltran R., Travesset A., Calleja M. Ll., Delgado-Huertas A. and Marbà N. Estuaries Coastal and Shelf Science 196: 31-44, (2017).
Characterization of light absorption by chromophoric dissolved organic matter (CDOM) in the upper layer of the Red Sea. Kheireddine, M., Ouhssain M., Calleja M. Ll., Sarma Y.V.B, Morán X.A.G., Tiwari S.P. and Jones B.H. Deep Sea Research oart I Oceanographic Research Papers, DOI: 10.1016/j.dsr.2018.02.001 (2018).
Glacier inputs influence organic matter composition and prokaryotic distribution in a high Arctic fjord (Kongsfjorden, Svalbard). S. Bourgeois, Kerhervé P., M. Ll. Calleja, Many G. and Morata N. Journal of Marine Systems 164: 112-127, (2016).
Major hydrogeochemical processes in an Acid Mine Drainage affected estuary.  M. P. Asta, M. Ll. Calleja, R. Pérez-López, L. F. Auqué. Marine Pollution Bulletin, Volume 91: 295-305, (2015)
Ocean-atmosphere exchange of organic carbon and CO2 surrounding the Antarctic Peninsula.  S. R. Ruiz-Halpern, M. Ll. Calleja, J. Dachs, S. Del Vento, M. Pastor, M. Palmer, S. Agustí, C. M. Duarte. Biogeosciences, Volume 11: 2755-2770, (2014)
Prevalence of strong vertical CO2 and O2 variability in the top meters of the ocean. M. Ll. Calleja, C.M. Duarte, M. Álvarez, R. Vaquer-Sunyer, S. Agustí, G. J. Herndl. Global Biogeochemical Cycles, Volume 27: 1-9, (2013).
Changes in compound specific δ15N amino acid signatures and D/L ratios in marine dissolved organic matter induced by heterotrophic bacterial reworking. M. Ll. Calleja, F. Batista, M. Peacock, R. Kudela, M. D. McCarthy. Marine Chemistry, Volume 149: 32-44, (2013).
Mesopelagic prokaryotic bulk and single-cell heterotrophic activity and community composition in the NW Africa-Canary Islands coastal-transition zone. J. M. Gasol, L. Alonso-Sáez, D. Vaqué, F. Baltar, M. Ll. Calleja, C. M. Duarte, J. Arístegui. Progress in Oceanography, Special Issue on EBUS, Progress in Oceanography, Volume 83: 189-196, (2009).
Evidence for surface organic matter modulation of air-sea CO2 exchange. M. Ll. Calleja, C.M. Duarte, Y.T. Priarie, S.Agustí, G.J. Herndl. Biogeosciences, Volume 6, 1105-1114, (2009).
The relationship between seagrass (Posidonia oceanica) decline and sulfide porewater concentration in carbonate sediments. M. Ll. Calleja, N. Marbà, C.M. Duarte. Estuarine Coastal and Shelf Science, Volume 73:583-588, (2007).
Control of air-sea CO2 disequilibria in the subtropical NE Atlantic by planktonic metabolism under the ocean skin. M. Ll. Calleja, C.M. Duarte, N. Navarro, S. Agustí. Geophysical Research Letters. Volume 32, L08606, (2005).


​Ph.D., Marine Sciences, Universitat de les Illes Balears, Palma de Mallorca, Spain, 2007
B.Sc., Chemistry, Universidad de Barcelona, Barcelona, Spain, 1999

Professional Profile

​2015-present: Researcher, KAUST, Thuwal, Saudi Arabia
2011-2014: Postdoctoral Researcher, Consejo Superior de Investigaciones Científicas (CSIC), Granada, Spain,
2008-2010: Postdoctoral Fellow, University of California Santa Cruz (UCSC), California, USA, 2008-2010

Scientific and Professional Memberships

American Society of Limnology and Oceanography (ASLO)


Young Investigator Award. ISOCOMPOUND'09 European Science Foundation (ESF) and National Science Foundation (NSF) networks, Postdam, Germany, 2009

KAUST Affiliations

​Red Sea Research Center (RSRC)
Biological and environmental science and engineering division (BESE)