Underground Explorers

The French insular territories of the South Indian Ocean (“Subantarctic” and “Eparse” Islands) are among the most isolated habitats on Earth that are protected by the French government through the “Terres Australes et Antarctiques Françaises (TAAF, https://taaf.fr/), that greatly limit human impacts and biological introductions, and preserves the local and endangered flora and fauna. These volcanic islands emerged between 130 million and 700,000 years ago and shaped unique habitats such as coastal, tundra and peatland ecosystems, influenced by Tropical or Westerly Winds. On these islands, recent studies have revealed a majority of unclassified fungi but no mycorrhizal fungi has been sequenced yet, whereas observations have been made on several plants. Supported by the logistics of the French Polar institute (IPEV) and the TAAF, we will sample soils from various districts: Crozet, Kerguelen and Amsterdam islands in the Subantarctic sector, and Tromelin island in the Eparse sector, where fungal habitat diversityremains greatly unexplored. Our expert team focuses on mycorrhizal diversity but also atmospheric dust particles, allowing us to evaluate how far local diversity could be influenced by long distance dispersal and Westerly Winds crossing theSouthern Indian Ocean.