Effects of soil burn severity on germination and initial establishment of maritime pine seedlings, under greenhouse conditions, in two contrasting experimentally burned soils

Abstract

The effects of soil burn severity on initial establishment of maritime pine in burned areas are not well known. Many factors may interact in the field, thus making it difficult to determine the exact role played by soil burn severity in the post-fire regeneration process. Monoliths of two contrasting soils -an acid, coarse-textured soil, with high organic matter content, and a neutral heavy-textured soil with low organic matter content -were experimentally burned to provide two markedly different levels of soil burn severity. The burned monoliths were sown with Pinus pinaster seeds and then placed in a greenhouse under a preselected water regime to determine the effect of burn severity on emergence and initial establishment of pine seedlings. High soil burn severity in the coarse-textured soils delayed germination, increased mortality and temporarily decreased the height of pine seedlings in the first year after sowing. This response was affected by: soil heating level, soil C consumption, post-fire soil C, depth of burn and post-fire duff-depth. Ash had no influence on the above processes. These factors did not explain the variability in the response of regeneration variables in the heavytextured soils. The applicability of the results to field conditions is discussed.

Compounded disturbances in sub‐alpine forests in western Colorado favour future dominance by quaking aspen (Populus tremuloides)

“…Generally, compounded disturbances have the potential to alter post‐disturbance regeneration by either reducing seed source or by increasing the intensity of the secondary disturbance (Kulakowski & Veblen ), which in turn may negatively influence soil and other micro‐environmental conditions (Fonturbel et al. ). These two influences may be of minimal consequence for the vegetative reproduction of P. tremuloides .…”

Defining extreme wildland fires using geospatial and ancillary metrics

“…Fires can result in immediate, short-and long-term effects on terrestrial vegetation, soils, hydrology, atmospheric cycles and social systems (Seiler and Crutzen 1980;Smith et al 2005a;Goetz et al 2007;Brewer et al 2013). High intensity, stand-replacing fires can lead to long-term changes in vegetation structure and composition (Kashian et al 2006;Goetz et al 2007;Romme et al 2011) through various mechanisms, such as consumption of large woody debris (Smith and Hudak 2005;Hyde et al 2011Hyde et al , 2012, tree girdling (Kavanagh et al 2010), loss of seed sources (Rodrigo et al 2012) and changes in surface and soil properties (Tozer and Auld 2006;Roy et al 2010;Fontúrbel et al 2011Fontúrbel et al , 2012. As human populations grow and residential development expands, the effects of wildland fire on ecological systems are increasingly intertwined with human systems and warrant the evaluation of fire effects on socialecological systems.…”

Bark Beetles and High-Severity Fires in Rocky Mountain Subalpine Forests

“…Therefore, compounded disturbances have the potential to fundamentally change forest composition and future forest trajectories. Compounded disturbances can alter post-disturbance regeneration by either reducing seed source or by increasing the intensity of the secondary disturbance , which in turn may negatively influence soil and other microenvironmental conditions (Fonturbel et al 2011). These two influences may be of minimal consequence for species that reproduce vegetatively, such as quaking aspen (Populus tremuloides), which has been shown to dominate initial regeneration following compounded disturbances, sometimes in stands dominated by conifers before the initial disturbance .…”