Communities in fire-affected ecosystems possess unique traits that aid survival and ecosystem recovery post-fire. As fires increase in frequency and intensity due to climate change, understanding the functions of these communities is essential. This work aimed to identify key functional traits of mycorrhizal fungi that correlate with fire regime and vegetative composition.
Thirty sclerophyll forest sites were selected within the Sydney Basin, Australia. These sites burned in the 2019-2020 Black Summer fires and varied in historical fire severity and interval. Vegetative composition, fungal communities, soil carbon and nutrient availability were analysed from each site. Mycorrhizal fungal biomass was harvested using mesh bags allowing us to measure functional traits associated with biomass production, hyphal chemistry (carbon, nitrogen, and phosphorus concentrations) and morphology (hyphal diameter and branching).
Mycorrhizal fungal composition was significantly associated with fire interval and nutrient availability. Fungal biomass production from a subset of twelve sites was greater in sites with a shorter fire interval, correlated with available phosphorus, and had more consistent hyphal carbon: nitrogen concentrations.
While previous work has been done on the presence or absence of mycorrhizal fungi post-fire, generally using DNA-based approaches, there is limited knowledge about the functions they serve. Here we show a significant effect of fire regime and nutrient availability on mycorrhizal fungi and will use trait data to elucidate the functional consequences of these communities.
By integrating responses associated with stoichiometric and morphological traits, fungal community composition, and environmental factors, the research seeks to provide a holistic understanding of the functional implications arising from these variations.