Get to know the researchers in Environmental Geochemistry!
Tom Jilbert

Tom is Associate Professor of Environmental Geochemistry and former Academy Research Fellow at the Department of Geosciences and Geography in Kumpula. He is deputy director of the Doctoral Program in Geosciences (GeoDoc) and of the Master's Program in Geology and Geophysics (Geo^2). His research is specialized in sediment biogeochemistry in human-impacted aquatic systems such as the Baltic Sea and eutrophic lakes. Tom is a member of the editorial boards of Chemical Geology, Frontiers in Earth Science and Frontiers in Marine Science, and co-ordinates the international symposium on lake restoration Lahti Lakes. He also participates as a key researcher in the CoastClim Centre.

Tom on Google Scholar, Research Portal, Research Gate, Twitter, and Bluesky

Primary teaching responsibilities:

  • GEOM2007 Environmental Geochemistry
  • GEOM2038 Solid Earth Geochemical Methods
  • ECGS-011 Advanced Aquatic and Sediment Biogeochemistry
  • ENV-312 Akvaattinen Biogeokemia


Kaarina Weckström

Kaarina is a University Researcher who is also employed at Sitowise. She is a palaeoecologist interested in the reconstruction of past climate and environments using both marine and freshwater sediment proxy records. Her expertise includes marine, brackish and freshwater diatom taxonomy and ecology, and sediment biomarkers (especially IP25), with a special interest in proxy evaluation and development. Within the Environmental Geochemistry group, Kaarina works on reconstructions of paleoenvironmental change in the Black Sea and Baltic Sea using a combination of geochemical and paleoecological data. In earlier projects, Kaarina has studied recent eutrophication history of the Baltic Sea, the effects of groundwater phosphorus concentrations on lake trophic state, and Arctic environmental change.

Kaarina on Google Scholar and Research Portal.

Martijn Hermans

Martijn is a Postdoctoral Researcher specialized in electromicrobiology and marine biogeochemistry. Martijn was funded by the Academy of Finland Research Fellowship of Tom Jilbert for 2 years and is now affiliated at Stockholm University. His past research has focused on the impact of cable bacteria on coastal sediment biogeochemistry. In the Environmental Geochemistry group he is implementing coupled sedimentary iron and phosphorus dynamics into the BALTSEM model of the Baltic Sea. Among many applications, this model expansion can be used to gain a better mechanistic understanding of multidecadal feedbacks in oxygen conditions. His work is connected to collaborators including Bo Gustafsson (Stockholm University, Baltic Sea Centre) and Caroline Slomp (Radboud University, Netherlands).

Martijn on Google Scholar and Research Gate.


Rahat Riaz

Rahat is a Postdoctoral Researcher specialized in organic and contaminant geochemistry. She completed her PhD in Pakistan, studying persistent organic pollutants in lakes and soils of her home country. Within the Environmental Geochemistry group, Rahat is studying the inputs of terrestrial organic matter from human activities into coastal sediments of the Baltic Sea. Land use change, forest industries and deposition of atmospheric pollutants have markedly altered the fluxes of terrestrial organic matter into the Baltic on various timescales. In her work Rahat focuses on the use of lignin phenols as a tracer for terrestrial plant material in coastal sediments. Understanding the inputs of such material is important for quantifying carbon transfers and burial in the coastal environment. Rahat's work is funded by the Faculty of Science and connects to research in the Coastclim Centre.

Rahat on Google Scholar.

Ana Lindroth Dauner

Ana is a Postdoctoral Researcher specialized in marine and organic biogeochemistry. Her past research involved the assessment of marine pollution from oil and sewage inputs to subtropical and Antarctic coastal areas, paleoreconstructions of temperature and organic matter input to open ocean systems, and the comparison of paleoarchives data with numerical model results to investigate how climate changes affect the carbon cycling in Arctic lakes. Within the Environmental Geochemistry group, Ana is studying the importance of vegetated areas in carbon burial in boreal lakes. Ana is funded by the Blue Lakes project (EU Recovery and Resilience Facility funding administered via the Academy of Finland).


Ana on Research Gate.

Mareike Paul

Mareike Paul is a Doctoral Researcher studying the mechanisms of trace metal enrichment in the sediments of coastal European seas, including the Baltic Sea, Black Sea and Swedish West Coast fjords. Many details of sedimentary trace metal chemistry are still poorly constrained, which limits the use of trace metal enrichments as quantitative recorders of (past) hypoxia. Mareike's work aims to shed light on the various factors that control trace metal enrichments by studying a wide range of locations under varying degrees of anthropogenic stress. The project is a collaboration with international partners and is funded by the Academy of Finland Research Fellowship of Tom Jilbert.

Mareike on Google Scholar, Research Portal and Research Gate.

Siqi Zhao

Siqi is a Doctoral Researcher studying sedimentary phosphorus dynamics in eutrophic lakes in the agricultural areas of southern Finland. Siqi is interested in the effect of internal loading of phosphorus on recovery from lake eutrophication, and especially in the recovery timeline. In her PhD work, she is comparing the differences of sedimentary phosphorus processes between lakes with contrasting catchment characteristics and histories of nutrient loading. She is also applying reactive transport diagenetic modeling to the study of lake sediment phosphorus dynamics. Siqi is a grant researcher funded by the China Scholarship Council.

Frederico Aragão

Frederico is a Doctoral Researcher working on the hypolimnetic withdrawal and treatment pilot project at Lake Kymijärvi, Lahti. His interests are primarily in the mechanisms of phosphorus retention and capture in filtration systems. He is performing column experiments to study the capture of precipitates in porous media in the context of filtration of nutrient-rich hypolimnetic water. Data from field and laboratory experiments will be used to build a hydrogeochemical model to simulate processes in the treatment units. His work aims to support optimization of infrastructure operation in future applications of hypolimnetic withdrawal and therefore to improve strategies for lake restoration. Frederico's work is supported by EDUFI, K.H. Renlund Foundation and the Doctoral program in Geosciences.


Nishant is a Doctoral Researcher working within the CoastClim PhD collegium. His research is focused on understanding carbon sequestration in coastal marine sediments, in particular the role of macroalgal material in sedimentary blue carbon burial. Nishant is sampling sediments from a range of coastal habitats in the Baltic Sea, to determine the carbon stocks and the sources of organic matter using phenolic biomarkers and other proxies. His work is funded by Nottbeck Foundation via Tvärminne Zoological Station.


Max Kankainen

Max is a Doctoral Researcher with a background in marine micropaleontology and sediment geochemistry. In his master thesis at University of Gothenburg he investigated the ecological temporal variability in coastal environments using benthic foraminifera, ostracods, heavy metals and sediment geochemistry as indicators. He also has experience working as a specialist in a laboratory that provides services for the identification of harmful substances. For his doctoral studies he is working within the Blue Lakes project. His research is focused on the burial potential of organic carbon in the vegetated areas of boreal lakes. By analysing sediment samples his aim is to deliver new understanding into the role of boreal lakes as natural carbon sinks and shed light on the effect that climate change and anthropogenic activity can have on carbon burial.

Max on Google Scholar and Research Gate.

Yanmin Wang

Yanmin is a visiting Doctoral Researcher studying sedimentary phosphorus dynamics in the mariculture areas of the Archipelago Sea in southwestern Finland. Her previous research at Xiamen University focused on biogeochemical processes in the hypoxic zones and mariculture areas of the coastal ocean in China. Within the Environmental Geochemistry group, Yanmin is also synthesizing a database of sediment biogeochemistry in various mariculture areas worldwide, to better understand impacts of mariculture on sedimentary phosphorus processes. Yanmin is a grant researcher funded by the China Scholarship Council.

Former group members

The group was previously located at the EcoEnv research program as the Aquatic Biogeochemistry Research Unit (ABRU). Researchers who have been affiliated to ABRU and Environmental Geochemistry since 2015 include:

Susanna Hietanen

Karoliina Koho

Eero Asmala

Dana Hellemann

Saija Saarni

Sami Jokinen

Jesse Harrison

Myrsini Chronopoulou

Soila Silvonen

Iines Salonen

JP Myllykangas

Antti Rissanen

Petra Tallberg