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Wildfires significantly impact hydrology and geomorphology by altering soil properties, which depend on the fire intensity, duration, and frequency. Soil organic matter (SOM) is vital for forest ecosystems, acting as fuel. In this study, unburnt and burnt soils were collected from nearby locations for a prescribed fire site. Additional samples were tested where unburnt soil was mixed with 25% volume of mulch and exposed to a temperature of 150°C and 650°C in a furnace to simulate the exposure to soil with organic matter to high temperatures experienced during wildfires. The variation of soil-water characteristic curves (SWCCs) for these different soil samples was evaluated to assess the impact of exposure to high temperature during wildfires. Results showed that low-intensity fires did not alter soil properties, while high-intensity fires resulted in a change in the soil property in terms of SWCC and physical and hydraulic characteristics, and posed greater erosion risks and disrupt soil stability, highlighting the need for better soil management strategies. 

Parasites harm host fitness and are pervasive agents of natural selection capable of driving the evolution of host resistance traits. Previously we demonstrated evolutionary responses to artificial selection for increasing behavioral immunity to Gamasodes queenslandicus mites for Drosophila melanogaster. Here, we report transcriptional shifts in metabolic processes due to selection for mite resistance. We also show decreased starvation resistance and increased use of nutrient reserves in flies from mite-resistant lines. Resistant lines exhibited increased activity, reduced sleep, and elevated oxygen consumption during the night. Using a panel of D. melanogaster lines exhibiting variable sleep durations, we found a positive correlation between mite resistance and reduced sleep. Restraining the activity of artificially selected mite-resistant flies during exposure to parasites reduced their resistance advantage relative to control flies. The results suggest that ectoparasite resistance in this system involves increased activity during the scotophase and metabolic gene expression at the expense of starvation resistance.