Microenvironment characteristics and early regeneration after the 2018 Spring Creek Wildfire and post-fire logging in Colorado, USA

Abstract

Background Wildfires are increasing in size and severity in forests of the western USA, driven by climate change and land management practices during the 20th century. Altered fire regimes have resulted in a greater need for knowledge on best practices for managing burned landscapes, especially in instances where a return to a previous forested ecosystem is desired. We examined a large wildfire from 2018 in southern Colorado to understand how fire severity and post-fire logging influenced stand structure, fuels, vegetation, and soil microsite conditions. Results Two years post-fire and 1 year post logging, there was no difference in understory vegetation response. Logged plots demonstrated lower daily average temperature and minimum soil moisture and higher fuel loading across most fuel size classes relative to unlogged plots, which also corresponded with a loss of dead standing wood and little to no canopy cover. Early post-fire conifer regeneration was low across all plots, but lower soil moisture and higher soil temperature negatively impacted the density of regeneration. Conclusions Successful tree regeneration is mediated by multiple factors from the microsite to landscape scale. Here, we demonstrate the importance of those microsite conditions such as soil moisture and temperature in predicting conifer tree establishment in the early post-fire period. Careful consideration of soil impacts and the associated changes to forest conditions should be taken when conducting post-fire logging to prevent detrimental effects on microsite conditions and forest recovery.

Influence of Mixed Conifer Forest Thinning and Prescribed Fire on Soil Temperature and Moisture Dynamics in Proximity to Forest Logs: A Case Study in New Mexico, USA

“…These studies, combined with other results from clear-cutting and salvage-logging operations [13,19,25,[41][42][43][44][45][46][47][48][49][50][51][52][53][54][55], indicate a wide variety of responses in soil temperatures and moisture depending on site-specific circumstances. In our mixed conifer forests of northern New Mexico, the retention of natural logs following thinning and burning provided microsites with generally warmer sub-log soil temperatures in spring, summer, and fall, while adjacent sites experienced comparable warming levels.…”

Spatially explicit models of seed availability improve predictions of conifer regeneration following the 2018 Carr Fire in northern California

“…Milleroń et al (2013) found large disparities between seed dispersal kernels and kernels from established saplings, suggesting that dispersal alone is insufficient to capture patterns in recruitment and survival. Although we attempted to include variables that might distinguish between site quality and thus the probability of seedling establishment, we simply could not precisely determine the effects of site quality (i.e., soil moisture or temperature, see Wooten et al, 2022) with our data. For example, the presence of downed logs and shrubs can provide protection and increase soil moisture for regenerating seedlings (Tappeiner and Helms, 1971;Landesmann and Morales, 2018;Marcolin et al, 2019).…”

Controlled Burning and its Effects on Shorea robusta (Sal) Regeneration in Dhansar Block Forest, Rautahat

“…Fire-tolerant plant species generally increased in abundance at the expense of those killed by fire (fire-sensitive plants) due to a considerable reduction in competition and possibly due to alternations in other conditions (Gallagher et al, 2022). Regeneration of post-fire trees depends on a variety of factors, from climate suitability to the characteristics of the microsite (Wooten et al, 2022). A successful reestablishment post-fire may be influenced by seed source, climate, competition or facilitation, and micro-climates (Stevens-Rumann and Morgan, 2019).…”