Xosé Anxelu G. Morán


Adjunct Associate Professor of Marine Science

Research Interests

​Professor Morán’s microbial oceanography and ecology research is focused on small-sized planktonic organisms (viruses, prokaryotes, phytoplankton) and their role in biogeochemical cycles. Before joining KAUST and the Red Sea Research Center (RSRC), Morán had a long and distinguished research career in his native Spain. After completing his Ph.D. and a one year postdoc contract at the Institut de Ciències del Mar (CSIC) in Barcelona, he then went on to work as a researcher for 14 years at the Instituto Español de Oceanografía in Gijón/Xixón.

His research interests at KAUST include the study of the dynamics and metabolic ecology aspects of planktonic prokaryotes (bacteria and archaea), their interactions with dissolved organic matter, and microbial plankton responses to global warming.

Having worked in several oceanographic research expeditions throughout his career in Spain, including extremely cold environments, Morán saw that by joining KAUST he could continue his branch of research in a relatively unexplored part of the world. The move to Saudi Arabia would give him the opportunity to work in a unique and ecologically highly relevant, tropical marine environment.

"In Spain, I was working mostly on the interactions between phytoplankton and bacterioplankton, that is, between phototrophic and heterotrophic microbes, in the water column of temperate latitude sites. I was happy there, but then there was an advertised position open here at KAUST. It was advertised as exploring the ecology of plankton living in extreme environments."

"I saw KAUST as an opportunity to get to go to a place and be able to work in a unique environment by the Red Sea. The amount of effort and the multidisciplinarity that we are achieving here at KAUST is unthinkable of in other places. The services that KAUST provide to their researchers, the possibility of doing so many things here without having to outsource your analysis somewhere else is unique," he said.

Morán has a passion for biology that stems from his youth growing up in Asturias, a coastal and mountainous region of Northern Spain. Summers spent birdwatching and catching small reptiles, fishes and insects to observe fueled a burgeoning passion for biology, and its preservation, that has remained with Morán up until today.

"One of the research lines that I have been more focused over the recent years is the effect of global warming in pelagic ecosystems. Many RSRC and KAUST PIs are working on global change research because of the general concern surrounding the topic. I try to contribute to determining which direction of change we can expect for microbial communities in the future global ocean. The assessments and the experiments we can do here in the Red Sea can be useful for predicting the responses of organisms to global warming in other parts of their world," he noted.

Morán acknowledges that his research findings, or the scientific contributions that may develop from his research, may not have an obvious application for the Saudi economy or any other economy in the world.

"My type of research in marine pelagic ecosystems doesn't bring an immediate application of technologies that can be used or to have an economic impact. We should not forget that basic science is also essential. Many of the applications that have been produced through human history have come about from purely curiosity-driven questions," he said.

"I don't think we should forget that the freedom to do research and basic science should be warranted in the world. This is my personal opinion. With non-applied science, there should be no pressure to potential economic obligations. As researchers, we're contributing to the world's knowledge base. I also find it very interesting to be able to speak, to teach, and to show KAUST students (a unique blend from all over the world) your research, and how you approach science. A lot of positive outcomes derive from sharing knowledge," Morán emphasized.

Selected Publications

  • Low abundances but high growth rates of coastal heterotrophic bacteria in the Red Sea 
    L. Silva, M.L. Calleja, T.M. Huete-Stauffer, S. Ivetic, M.I. Ansari, M. Viegas and Xosé An...
    Front. Microbiol., (2018)
  • Temperature sensitivities of microbial plankton net growth rates are seasonally coherent and linked to nutrient ava... 
    X. Anxelu G. Morán, A. Calvo‐Díaz, N. Arandia‐Gorostidi, T.M. Huete‐Stauffer
    Environmental Microbiology, 20(10), pp. 3798-3810 , (2018)
  • The Mesopelagic Scattering Layer: A Hotspot for Heterotrophic Prokaryotes in the Red Sea Twilight Zone 
    M.L. Calleja, M.I. Ansari, A. Rostad, L.R. da Silva, S. Kaartvedt, X. Irigoien, X.A.G. Mor...
    Front. Mar. Sci., (2018)
  • Diel dynamics and coupling of heterotrophic prokaryotes and dissolved organic matter in epipelagic and mesopelagic ... 
    F.C. García, M.L. Calleja, N. Al‐Otaibi, A. Røstad, X.A.G. Morán
    Environmental Microbiology, 20(8), pp. 2990-3000, (2018)
  • Large Plankton Enhance Heterotrophy Under Experimental Warming in a Temperate Coastal Ecosystem 
    Tamara Megan Huete-Stauffer, Nestor Arandia-Gorostidi, Natalia González-Benítez, Laura Día...
    Ecosystems, pp. 1-16, (2017)
  • Testing the metabolic theory of ecology with marine bacteria: different temperature sensitivity of major phylogenet... 
    N. Arandia-Gorostidi, T. Huete-Stauffer, L. Alonso-Saez, X. Anxelu G. Morán
    Environmental Microbiology, volume 19, issue 11, pp. 4493-4505 , (2017)
  • Temperature regulation of marine heterotrophic prokaryotes increases latitudinally as a breach between bottom-up an... 
    X.A.G. Morán, J.M. Gasol, M. Pernice, J.-F. Mangot, R. Massana, E. Lara, D. Vaqué, and C....
    Global Change Biology, (2017)
  • Experimental Warming Decreases the Average Size and Nucleic Acid Content of Marine Bacterial Communities 
    T.M. Huete-Stauffer, N. Arandia-Gorostidi, L. Alonso-Saez, X.A.G. Moran
    Frontiers in Microbiology, volume 7, article 760, (2016)
  • More, smaller bacteria in response to ocean’s warming? 
    X.A.G. Morán, L. Alonso-Sáez , E. Nogueira, H.W. Ducklow, N. González, Á. López-Urrutia, L...
    Proceedings of the Royal Society B-Biological Sciences, 282, 20150371, (2015)
  • Temperature affects the size-structure of phytoplankton communities in the ocean 
    Á. López-Urrutia, X.A.G. Morán
    Limnology and Oceanography, 60, pp. 733-738, (2015)


  • ​Ph.D., Biology, University of Oviedo/Uviéu, Spain, 1999
  • B.Sc., Biological Sciences, University of Oviedo/Uviéu, Spain, 1992

Professional Profile

  • 2014-current: Associate Professor of Marine Science, KAUST, Thuwal, Saudi Arabia
  • 2008: Sabbatical, Ecosystems Center, MBL, Woods Hole, USA,
  • 2001-2014: Senior Scientist, Oceanographic Center of Gijón/Xixón, IEO, Gijón/Xixón, Spain
  • 2000:Postdoctoral fellow, Institute of Marine Sciences, CSIC, Barcelona, Spain

Scientific and Professional Membership

  • ​​Association for the Advancement of the Sciences of Limnology and Oceanography (ASLO)

KAUST Affiliations

  • KAUST Red Sea Research Center (RSRC)
  • Biological and Environmental Sciences and Engineering Division (BESE) ​

Research Interests Keywords

Ecology Climate Change Marine ecology Marine biology Biogeochemistry Aquatic ecosystems Biological Oceanography Phytoplankton