Spatiotemporal dynamics of fine dead surface fuel moisture content in a Colorado mixed-conifer forest

Background Dead fine fuel moisture content (FMC) is critical for predicting fire behavior and effects. Spatiotemporal variation in FMC occurs due to to variability in atmospheric conditions at the fuel interface, which is influenced by interacting factors including local forest structure and topography. Previous research has primarily examined these patterns over coarse spatial scales and relied on few factors to explain variability. Aims In this study, we monitored the spatiotemporal variability in FMC and characterized how controls of FMC vary over a fire season. FMC was sampled at 80 locations 21 times (approximately weekly) through the summer season in a 17.6 ha southern Rocky Mountain mixed-conifer forest. Key results Results indicate that FMC variability declines during drier periods and that the influence of forest structure and topography on FMC is constant through time under fluctuating precipitation patterns. FMC values are autocorrelated over spatial and temporal scales and are highly variable over fine spatial scales. Conclusions Understanding the full magnitude of FMC variability is important for achieving management objectives under both prescribed and wildfire conditions. Implications Further research into FMC variability and its controls could lead to more reliable models and tools allowing managers to better predict fire behavior and effects.