Emmy Ratto

Hello everyone,

I am Emmy Ratto, and I am a geography student at Toulouse University Jean Jaurès (France). In November 2024, I had the opportunity to participate in an internship supported by the PermaIntern platform. This internship took place at Sherbrooke University (UdeS) with the Department of Applied Geomatics, under the supervision of Professor Frédéric Bouchard.

Before that, for my undergraduate internship during my third year, I worked at the CNRS GEODE laboratory in Toulouse. My project focused on analyzing sediment cores from glacial Lake Barbazan, located in the French Pyrenees (Haute-Ariège).

In Sherbrooke, I joined the GRIMP (Groupe de recherche interdisciplinaire sur les milieux polaires) to contribute to Lucile Cosyn Wexsteen's PhD thesis, which explores the recent drying-up of lakes in the Hudson Bay Lowlands and its impact on terrestrial ecosystems. This has enabled me to develop interdisciplinary approaches to analyzing the evolution of these lakes through the study of sedimentary archives.

In the laboratory, I carried out various analyses on sediment cores sampled in 2023. For instance, I used the Loss-on-Ignition (LOI) method, which quantifies the percentages of organic matter and carbonates in samples by subjecting them to different combustion temperatures (550°C and 950°C, respectively). The analyses revealed that the sediments contained more than 95% of organic matter, consistent with the characteristics of the nearby lakes studied. This highly organic composition suggests a relatively recent formation of the lake, which developed in a peat-rich environment.

The second part of my work involved identifying and analyzing diatoms (siliceous fossil microalgae) found in the sediments of another lake in the same ecozone, called the peat plateau. This meticulous work enabled me to explore the diversity of microfossils and their role as paleoenvironmental indicators. The analyses revealed a high dominance of oligotrophic benthic species, indicating a shallow, nutrient-poor lake. This method has enabled us to gain a better understanding of the evolution of the environment and to trace historical changes within the surrounding basin.

In parallel, I also worked on Geographic Information Systems (GIS). The data utilized enabled the creation of detailed maps of the studied areas, highlighting seasonal changes in water bodies and vegetation development in the region.

This enriching experience, both academically and personally, strengthened my motivation to pursue a career in research. I warmly thank Frédéric Bouchard and Lucile Cosyn Wexsteen for their guidance and availability, as well as the PermaIntern team for this unique opportunity. Exchanges with other students in the group, regarding their research in Arctic environments, gave me a broader perspective on ongoing studies in these regions.

I highly recommend the PermaIntern program to any student wishing to expand their skills and explore new scientific horizons.