Effect of Engineered Fungal Mycelium Growth on Infiltration and Erosion Resistance in Fire-Affected Soils

This study explores the potential of engineered fungal mycelium growth, using Pleurotus ostreatus , as a nature-based approach for stabilizing fire-affected soils. Burned and unburned soil samples were prepared under controlled conditions, including a laboratory-simulated wildfire setup to replicate post-fire hydrophobicity and soil degradation. A slurried mycelial inoculum was applied to selected specimens, and infiltration and erosion resistance were monitored over an eight-day incubation period. Results showed significant reductions in both infiltration and erosion for treated samples, particularly after surface mycelial sealing became established. By days 6-8 post-inoculation, fungal treatment achieved complete infiltration suppression (Philip model parameters S = 0, A = 0) compared to measurable infiltration in untreated controls. There is an improvement in erosion resistance, with treated specimens classified as having low erodibility versus highly erodible for untreated samples. The observed negative or near-zero Philip infiltration model parameters in later growth stages indicate the development of water-repellent mycelial layers that restrict surficial and subsurface flow. The findings highlight the ability of fungal growth to physically protect the soil surface, increase cohesion, and offer short-term stabilization, potentially serving as a precursor to longer-term ecological recovery in thermally degraded soil systems. However, field validation across diverse environmental conditions and evaluation of ecological impacts on native microbial communities and vegetation establishment are necessary before broader implementation. This work proposes the integration of fungi-based treatments into post-wildfire restoration strategies as a biodegradable, cost-effective complement to existing soil rehabilitation practices.