Bastien Parisy received a dissertation award from the Faculty of Agriculture and Forestry

The Faculty of Agriculture and Forestry has awarded PhD a dissertation prize of one thousand euros for his doctoral dissertation completed in 2024. The dissertation consists of five original articles and a summary. The research aims to characterize plant-microbe interactions across the Arctic and understand the simultaneous impacts of biotic and abiotic conditions on these interactions in the context of climate change. The study focuses on interactions between plants and soil microbes, specifically fungi and bacteria, across various environmental gradients in the Arctic region. The research reveals that environmental filtering has a stronger impact on community and interaction structure than the dispersal capacity of organisms, and that abiotic factors governing plant and bacterial occurrences differ from those structuring fungal communities. In conclusion, environmental shifts will significantly alter the interaction structures between plants and soil microbes and potentially affect plant communities.

The award committee praised the strong personal contribution of PhD Bastien Parisy in all phases of the research, from conceptualization to writing, noting that he is the first or shared first author in all original articles. Additionally, the research methods in this topical research are innovative and employed in an original and elegant manner. The thesis is very strongly linked to clearly stated hypotheses, and articles form a cohesive story.

After completing his dissertation, Bastien Parisy has continued his research career as a postdoctoral researcher at the Faculty of Biological and Environmental Sciences.

- I am currently working on the Calanda Biodiversity Observatory project, led by Professor Anna-Liisa Laine. My aim is to investigate the temporal dynamics of plant and associated community composition and evaluate how such shifts may influence herbivory and disease intensity under changing environmental conditions. During my PhD, I began to unravel the mechanisms underlying plant–soil microbe interactions in the Arctic region and now I further explore how such changes in interactions may impact ecosystems processes.

Parisy expresses his enthusiasm for further contributing to this research field.

- Understanding how changes in plant–organism interactions affect ecosystem sustainability in the context of climate change is more critical than ever. I believe that the knowledge and analytical skills I developed during my PhD have proven highly valuable for my current and future research, Parisy concludes.

Dissertation award of the Faculty of Agriculture and Forestry

The award committee, consisting of the Dean and Vice Deans of the Faculty of Agriculture and Forestry, annually selects the recipient of the dissertation award. The prize-winner will be selected from dissertations with the grade approved with distinction. In 2025, the recipient of the faculty dissertation award was selected from the dissertations with the grade approved with distinction in 2024.

Doctoral dissertation: Bastien Parisy. Dissertationes Universitatis Helsingiensis 265/2024.