Underground Explorers

In central Australia, the Simpson desert is composed of parallel sand dunes that run for hundreds of kilometers. It has the particularity to encompass a network of rivers that originate in subtropical regions with high rainfall and penetrate into the dune fields from the North. Oncoming floods create the largest ephemeral wetlands in arid Australia, bringing water and sediments that contribute to soil fertility and dune formation. These exceptional conditions engender a relatively luxuriant vegetation compared with other arid regions that receive similar rainfall. While most plant species in the Simpson desert associate with arbuscular mycorrhizal fungi, Acacia and Eucalyptus shrubs that colonize interdunal corridors and riparian habitats can form mycorrhizal associations with ectomycorrhizal fungi, including iconic desert truffles. There is mounting evidence that drought conditions provoke plant nutrient deficiencies and that mycorrhizal fungi improve plant drought tolerance, but knowledge on mycorrhizal associations from arid regions is limited. We aim at filling this gap by establishing baseline knowledge of mycorrhizal diversity across landscapes in the Simpson Desert. We hypothesize that arbuscular mycorrhizal diversity is generally low and structured based on habitat type across the dune-interdune sequence, while riparian habitats within the desert are a source of ectomycorrhizal diversity.