This study characterizes post-fire recovery of microbial and fungal populations adjacent to three keystone chaparral plant species affected by varying burn intensities via systematic measurement of soil respiration. The CO2 released from soil surrounding Ceanothus spinosus, Heteromeles arbutifolia and Malasma laurina affected by mild, severe or no heat during the Woolsey Fire of November 2018 were monitored and used as an indicator of microbial, fungal, and root activity. We hypothesized that soil which experienced less intense heat would exhibit higher rates of respiration based on preliminary data taken in March 2019. However, the opposite was observed from May through July 2019 as hot burn sites exhibited a significantly greater respiration than cool burn. This occurrence could be explained by the early proliferation of nonnative annual grasses in cool burn sites post fire driving high rates of respiration which decline as the weeds become dormant in summer. However, areas dominated by native chaparral are able to continuously recover and provide suitable media for microbial and fungal development.
Irving, Mari R. and Davis, Stephen D., "Post-Fire Soil Microbiome Recovery and Respiration in a Chaparral Ecosystem" (2019). Pepperdine University, Featured Research. Paper 150.