Below you find a short summary of some of my ongoing projects or projects that have been published.
Marine primary producers in a future climate: an eco-evolutionary approach combining experimental ecology and metagenomics (Academy of Finland postdoc)
Project period: September 1st 2019 - August 31st 2022
Primary production, the build-up of organic carbon, is considered the most valuable process in the global ocean. The major part of the
marine food web depends on the inherent energy of this organic matter, produced by autotrophic unicellular organisms, or so called
phytoplankton. However, the Earth and its ecosystems are rapidly moving into a new human-mediated geological epoch named the
Anthropocene. In the face of the ongoing anthropogenic Global Change, the key planktonic realm is subjected to new environmental
conditions, inevitably forcing species to adaptive evolution or local extinction. Given a likely scenario, can we predict the performance
and eco-evolutionary responses of diverse autotrophic organisms responsible of fundamental processes in the marine ecosystem? A
potentially advisable approach to the question is to capitalize on the implicit ecological knowledge-potential of different types of
existing data, or data we are technically capable of producing today. The aim of the proposed research is to combine metagenome,
experimental and historic monitoring data to predict the effects of global climate change on primary producers in the ocean. The project
combines 1) beyond state-of-the-art metagenome population genomics, 2) transcriptome profiling of pre-Anthropocene revived resting
cells and 3) species distribution modelling of a key phytoplankton species across natural environmental gradients in a “Darwinian
laboratory”, the Baltic Sea-North Sea transition. The Baltic Sea model system acts as a “time machine”, providing us with invaluable
early-warning signs that facilitate the understanding of climate induced effects also in other coastal areas. The project will significantly
advance methodological norms within the field of molecular ecology focused on unicellular eukaryotes. Altogether, this will bolster our
ability to understand anthropogenically induced impacts on marine ecosystems, and diversify the environmental management toolbox
used in coastal areas around the world. These outcomes serve the targets included in United Nations Sustainable Development Goals,
especially the Climate Action and Life Below Water targets.
Anna Ikonen (BSc), Masters thesis (2021-)
Microbial and molecular biostimulation of resting stages of microalgae
Resurrection ecology tries to understand how, e.g. global warming, affects organisms. The best way is to use organisms that haven’t been exposed to the current conditions, and resting stages of diatoms are great for that. In my thesis I ask if you with addition of melatonin can wake up resting stages, or get cells to enter a resting phase. I also ask will there be any changes in growth if you add melatonin. The idea is to find better methods to be able to wake up even older resting stages than what we have accomplished so far. My results imply that the growth decreases with high concentrations of melatonin and melatonin seems to affect the production of resting stages, but not their ability to wake up.
Maximilian Gareis (BSc), Masters thesis (2020-)
In my thesis, we are investigating if the diatom Skeletonema marinoi has adapted to the increasing temperatures in the Baltic Sea during the last decades. We have resurrected resting stages from the years 1960, 1986 and 2012 (seven strains per time point). We expect that the strains from 1960 have a higher growth rate in the lower temperatures and that the strains from 2012 have a higher growth rate in the warmer temperatures. We also expect to observe a difference in cell size between the three time points. We grew the strains in four different temperature treatments (6, 8, 10 and 14 °C) and estimated growth rates using daily fluorescence measurements of in vivo chl a. In 6 °C, the strains from 1960 had the highest growth rate. The cell size results showed a difference between years (smaller in more modern populations) but no significant difference between temperatures.
Ronja Lanndér (BSc), Masters thesis (2020-)
Succession of the winter to spring phytoplankton community in the Åland Islands - a comparison of microscopic and rRNA gene analyses
Janni Heikkinen (BSc), Masters thesis (2019)
In my master’s thesis I investigated the importance of the microbiome associated with the diatom species Skeletonema marinoi in means of ecological performance, the change in the associated bacterial community composition when subjected to stress, whilst also considering the role of diatoms’ genetic diversity when the microbiome is stressed. These questions were answered by conducting laboratory experiments where antibiotics disrupt the bacteria associated with clonal and mixed strains of S. marinoi. This a subject of great importance, since knowledge regarding diatom-bacteria interactions in the Baltic Sea is very limited.