Contact Information

Department of Environmental Sciences
P.O. Box 65 (Viikinkaari 1)
00014 University of Helsinki

Niemenkatu 73
15140 Lahti

Aquatic Biogeochemistry Research Unit (ABRU)

In Aquatic Biogeochemistry, we study how the essential elements of life are cycled in water. In particular, we focus on carbon, nitrogen, phosphorus and silicon cycling. These are the key nutrients whose availability determine the distribution of life in Earth’s aquatic environments. We study the whole spectrum of aquatic systems, from lakes, through coastal marine environments to the open oceans. We are specialized in the study of sediments, where organic material is decomposed by microbes, releasing nutrients for further cycling in the environment.

The Aquatic Biogeochemistry Research Unit forms part of the Aquatic Sciences division at the department of Environmental Sciences. The unit contains three senior scientists: Assistant Professor Tom Jilbert, and Academy of Finland Research Fellows Susanna Hietanen and Karoliina Koho. There are currently four Ph.D. students, one Post-Doc. and one University Researcher in the unit. We collaborate actively with other research units at the department, and with national and international partners. Click on the links below to read more about our research!


Textruta:  Assistant Professor Tom Jilbert (tom.jilbert(at)
Tom was appointed Assistant Professor (Tenure Track) in Aquatic Biogeochemistry in January 2016. His position is co-funded by University of Helsinki and Vesijärvi Foundation. Tom’s current research interests include nutrient burial in eutrophied lakes and the distribution of metals in boreal estuaries
Textruta:  Academy of Finland Research Fellow Susanna Hietanen (susanna.hietanen(at)
Susanna leads the Nutrient Cycles in Aquatic Ecosystems research group. Her group studies the coupled cycles of nutrients (nitrogen, phosphorus and silicon) and carbon in the context of climate change and eutrophication in the Baltic Sea.
Textruta:  Academy of Finland Research Fellow Karoliina Koho (karoliina.koho(at)
Karoliina leads the Benthic Ecology and Sediment Biogeochemistry group. Her group works at the interface of ecology and biogeochemistry, investigating how benthic (micro)organisms influence oxygen dynamics, and nutrient and carbon cycling in sediments.