Current Group Members

Prof. Dr. Marco Keiluweit (he/him, PI)
Marco is an Associate Professor and the PI of the Soil Biogeochemistry Group in the Faculty of Geosciences and the Environment (FGSE) at the University of Lausanne (Switzerland). Since his years as a BSc student, Marco has been interested in the molecular mechanisms that underlie soil function, and its response to climate change.  He received his BSc in Geoecology fom the University of Tübingen (Germany) as well as MSc and PhD degrees in Soil Biogeochemistry from Oregon State University (USA). During his PhD, Marco worked as a Lawrence Scholar in the Isotope Signature Group at Lawrence Livermore National Laboratory (USA). After defending his dissertation in 2013, he joined the Environmental & Soil Biogeochemistry group at Stanford University (USA) as a Postdoctoral Scholar between 2014 and 2015. Marco became Assistant Professor of Soil Biogeochemistry at the University of Massachusetts-Amherst in 2016, before moving his group to UNIL in 2022.  
Dr. Floriane Jamoteau (she/her, postdoc)
Floriane joined the Soil Biogeochemistry group in April 2023 after completing her PhD thesis at CEREGE (France). Her PhD thesis focused on the characterization of soil organo-mineral associations at the micro- and nano-scale (nanoCLICs-type co-precipitates) and the monitoring of their fate after a land-use change and organic fertilization. As a post-doc, she is particularly interested in monitoring the fate of organo-mineral associations in the rhizosphere: such as their transformations, rates of formation and disruption at short and medium time scales (weekly to seasonal scale), as well as observing the underlying mechanisms through micro- and nanoscale analyses.
Dr. Emily Lacroix (she/her, postdoc) 
Emily joined the Soil Biogeochemistry group in January 2023. She received her BA in Chemistry modified with Environmental Studies from Dartmouth College (USA) and a PhD in Soil Biogeochemistry from Stanford University (USA). Emily is broadly interested in soil carbon cycling and specifically interested in how anoxic microsites, zones of oxygen depletion in otherwise oxic soils, may (or may not!) affect soil carbon cycling. Her postdoctoral work will investigate whether roots are key drivers of anoxic microsite formation and if root-associated anoxic microsites alter the fate of root-derived carbon.
Mariela Garcia Arredondo (she/her, PhD student)
Mariela joined the Keiluweit lab in Fall of 2016 after finishing her undergrad at Cornell University. Her BS was in Science of Earth Systems, which she concluded with an Honors thesis in soil organic matter regeneration for desertified grassland soils. She was awarded a Spaulding-Smith Fellowship and a National Science Foundation Graduate Research Program fellowship for her graduate research in the Soil Biogeochemistry Group focused on understanding and assessing how roots affect the soil’s C storage potential. Specifically, how rhizosphere processes can drive mineral-organic association vulnerability in soils. In the future, she would like to work as a soil scientist on either policy or project development for work focused on sustainable agriculture, soil remediation, and/or land development. During her free time she enjoys baking, gardening, and swimming.
Cam Anderson (they/them, PhD student)
Cam joined the Soil Biogeochemistry Group in May 2017. Their interests lie in understanding the factors that control biogeochemical processes, from the micro- to the ecosystem-scale. Their research uses both laboratory and field experiments to explore biotic and abiotic transformations of mineral-organic associations, with a focus on dynamic floodplain systems. Cam received their MSc in Soils and Biogeochemistry from UC Davis, and recently worked as a Research Associate at the Pacific Northwest National Laboratory, where they studied soil carbon cycling in high latitude systems.
Nathan A. Chin (he/him, PhD student)
Nathan joined the lab in Fall 2018 after completing his undergraduate BSc in environmental studies at Cornell University. At Cornell, Nathan completed an honors thesis looking at changes in enzyme activity in forest soils following increased nitrogen deposition and soil acidification. He is particularly interested in soil biogeochemical cycles nd how they interact with each other, particularly carbon. Branching out from his undergraduate experience, Nathan joined the Soil Biogeochemistry group to study manganese redox cycling in forest soils and how it links to organic matter decomposition. ​
Junna Frei (she/her, PhD student)
Junna received her MSc in Biology at the University of Neuchâtel specializing in Sustainable Agriculture and Chemical Ecology. During her thesis on biorecovery of phosphorus from digested sewage sludge using basidiomycetes, she developed a strong interest in mycology, particularly in the ability of fungi to recover nutrients from their substrate. At UNIL, she is involved in a research experiment aimed at determining the impact of changes in rainfall intensity on the dynamics of mineral-organic associations in the rhizosphere. She is particularly interested in investigating how fungi affect mineral-organic associations.
Dr. Xu Fang (he/him, postdoc)
Xu joined the Soil Biogeochemistry group in April 2024. He obtained his doctorate in August 2022 and did his first postdoc at ETH Zürich, where he investigated soil management strategies and the underlying biogeochemistry of decreasing As and Cd accumulation in rice. He is fascinated by the plant-mineral-microbe interactions in the rhizosphere of wetland plants where root-released oxygen meets the otherwise anoxic water-saturated soil matrix, dictating the fate of nutrients, toxins, and organic carbon in such soils. His postdoctoral research at UNIL will address how does organic carbon decomposition in the coastal marsh rhizosphere responds to tidal variations.

Current MS students

Egon van der Loo, MS Biogeosciences
Maël Luluc, MS Biogeosciences
Sébastien Meylan, MS Biogeosciences

Current Affiliates

Bouke Bentvelsen (she/her, Research Associate) - UNIL
Samuel Steiner (he/him, PhD Student) - Agroscope
Gabriella Griffin (she/her, PhD Student) - UMass Amherst
Chunlan Ni (she/her, PhD student) - CSC Fellow

Former Postdocs

Dr. Tobias Bolscher - Postdoc 2018-2021 - now Staff Scientist at the French National Institute for Agriculture, Food, and Environment (INRAE), Paris, France.
Dr. Xiao-Jun Allen Liu - Postdoc 2020-2021 - now Postdoc at University of Oklahoma
Dr. Morris E. Jones - Postdoc 2016-2019 - now Assistant Professor at Franklin Pierce University
Dr. Hui Li - Postdoc 2019-2020 - now Assistant Professor at NC State University

Former MS students

Nathan A. Chin - MS in 2022 - now PhD student in the Keiluweit Lab
Isobel Arthen-Long - MS in 2021 - now staff scientist at Tighe & Bond Environmental Consulting
Rachelle E. LaCroix - MS in 2018 - now PhD student at Cornell University (Lehmann Lab)

Former BS students

Shannel Thorpe - BSc in 2021 - now PhD student at UC Riverside
Jacob Ziegler - BSc in 2019 - now PhD student at University of Iowa
Genevieve Goebel - BSc in 2019 - now PhD student at Dartmouth (Hicks-Pries Lab)
Alex Gamble - BSc in 2020
Menli McCreight - BSc in 2018
Megan Wilcots - BSc in 2018 - now PhD student at Washington University
Sarah Pardi - BSc in 2018
Andrea Chica - BSc in 2017