Measuring and predicting disturbance resilience in ecosystems, with emphasis on fire: A review and meta-analysis

As disturbance regimes change in response to anthropogenic activities, ecosystem resilience is critically important to the persistence of biodiversity and ecological functions. However, resilience in literature is often treated as an abstract concept, with widely varying definitions. Achieving common and reliable resilience metrics that cross systems and contexts remains elusive. Here, we performed a systematic review and meta-analysis of studies that have performed ecological resilience quantification, aiming to identify factors that significantly promote resilience across systems, as well as indicators of resilience. Due to the recent emergence of costly megafires in many parts of the world, we additionally separately examined the subset of studies that focused on resilience to wildfire disturbance, specifically. For those studies that presented quantitative data on the strength of relationship between resilience and these variables, dispersal and connectivity as well as nutrients and chemistry emerged as significantly predictive of resilience, whereas animal communities and ecological functions were significant indicators of resilience. Meanwhile, other studies mapped or modeled resilience without testing the effects of individual variables; in these studies, resilience was bolstered by the presence of increased resources, increased habitat connectivity and diversity, and reduced disturbance severity. For fire studies, abiotic factors including light, moisture, and soil texture were significantly predictive of resilience, and the health of individual ecosystem components (such as tree survival) was significantly indicative of resilience. The power of meta-analysis in this arena remains limited due to few quantitative studies that test individual variables. Nevertheless, insights from the range of studies examined here are in alignment with resilience theory, which posits that resilience should be facilitated by reduced system change during disturbance, as well as by the removal of barriers to recovery. Our review therefore provides evidence to support management that lowers the severity of disturbance as well as restoration efforts that enhance resource availability and connectivity.