Soil fungi in ‘old-fields’ on semi-arid floodplains of the northern Murray-Darling Basin

Mr Reuben De Cocq Van Delwijnen¹

¹Griffith University, Brisbane, Australia

Abstract:

Fungi occur in almost all ecosystems and play critical roles in soil health, productivity, and regeneration, although the extent of knowledge regarding fungi is limited, especially with respect to soil fungi. Key knowledge gaps remain, for instance, regarding the role of soil fungi in the maintenance and regeneration of vegetation in abandoned agricultural fields, commonly known as ‘old-fields’. The extent of these has increased in recent times due to changing climatic and economic conditions. We sought to examine differences in the soil fungal assemblage structure, composition and function between old-fields and adjacent remnant vegetation patches in semi-arid floodplains of the northern Murray-Darling Basin Australia, and to explore potential drivers of these assemblages. We took samples of fungal e-DNA from five randomised plots in two habitat types at four locations in the northern Murray-Darling Basin to investigate patterns in soil fungal assemblages. Soil fungal species relative abundance was typically greater in remnant vegetation than in adjacent old-fields, but the proportions of each division identified was similar. Species of each soil functional group (saprotrophic, mycorrhizal, and pathogenic) were also present in both habitat types. Our findings suggest that although species relative abundance decreased in old-fields, likely due to land-use history, the community structure can persist or rapidly recover following abandonment and potentially retain function in these regenerating habitats. Our results also highlight the need for more research into the role of abiotic and biotic stressors in shaping soil fungi assemblages and their ecological functions.

Biography:

Reuben de Cocq van Delwijnen, first year PhD Candidate at Griffith University, in Brisbane. His current research focuses on arid soil fungal communities and the drivers behind these assemblages. He is also interested in using this knowledge for conservation and to potentially help improve agricultural pratices to preserve soil health under a changing climate.