With Cécile GUIEU and Karin SIGLOCH from the CNRS, Matthieu LENGAIGNE (IRD, MARBEC) is co-winner of the ERC-Synergy HARVEST grant worth €13 million.
The HARVEST project, Hydrothermal iron from the earth’s interior as fertiliser of photosynthesis in the ocean, studies how iron emitted by underwater volcanoes stimulates phytoplankton growth. Iron is an essential nutrient for marine life, but the contribution of this hydrothermal iron to biological productivity remains poorly understood. This is particularly true for shallow volcanism in the oceans, which can directly influence surface waters. HARVEST aims to fill this gap by assessing the role of iron from deep and shallow hydrothermal sources in primary production in iron-limited ocean areas, using an integrated approach combining field observations and modelling. The data collected, supported by advanced biogeochemical models, will be used to simulate the fate of hydrothermal iron and estimate its effects on primary production and the carbon cycle at regional and global scales, both now and in the future. By revealing the still poorly understood impact of submarine volcanism on ocean fertilisation, HARVEST will shed new light on the interactions between the solid Earth, ocean dynamics and marine ecosystems.
Biographie succincte des lauréats
Cécile Guieu, Director of Research at the Villefranche Oceanography Laboratory, is an oceanographer specialising in marine biogeochemistry. She is interested in external inputs of nutrients and particles into the ocean and their impact on marine biogeochemical cycles and carbon export in a context of anthropogenic and climatic change. For more than 30 years, she has been studying the processes involved in these inputs, whether of atmospheric origin or, more recently, hydrothermal origin, combining observations at sea with original experimental devices. After completing her PhD at Pierre and Marie Curie University in 1991 and two post-doctorates in the US (University of Rhode Island and Texas A&M University), she was recruited by the CNRS in 1994, conducting her research in marine biogeochemistry as part of projects in France (CNRS) and abroad (CALTECH, New York University Abu Dhabi).
Karin Sigloch's geophysical studies focus on the Earth's mantle. She prefers research topics that highlight how mantle processes strongly shape the habitable surface. Seismic imaging, global tectonics and ocean instrumentation have been essential tools in this regard. Karin Sigloch has been working as a research director at the CNRS at UMR Géoazur in Sophia Antipolis since 2021.
Matthieu Lengaigne is an oceanographer and research director at IRD, working within the MARBEC unit (Marine Biodiversity, Exploitation and Conservation, Montpellier). His research focuses on the variability and response of the tropical ocean-atmosphere system to climate forcings, as well as the influence of ocean physics on biogeochemistry and marine ecosystems. He is particularly interested in the climate of the tropical Indo-Pacific region and its changes in response to global warming. After completing his PhD at Pierre and Marie Curie University in 2002 and a post-doctorate at the University of Reading (United Kingdom), he was recruited by IRD in 2004. Since then, he has been developing his research at the interface between ocean dynamics, climate and marine biogeochemistry, mainly using numerical modelling, in close collaboration with numerous international partners, particularly in South Asia and the Indian Ocean. Winner of the CNRS bronze medal, he has played a leading role in international scientific coordination as chair of the Pacific Panel of the CLIVAR programme, which structures global research on climate variability and change in the Pacific Ocean.
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