Overlapping Bark Beetle Outbreaks, Salvage Logging and Wildfire Restructure a Lodgepole Pine Ecosystem

Abstract

Abstract:The 2010 Church's Park Fire burned beetle-killed lodgepole pine stands in Colorado, including recently salvage-logged areas, creating a fortuitous opportunity to compare the effects of salvage logging, wildfire and the combination of logging followed by wildfire. Here, we examine tree regeneration, surface fuels, understory plants, inorganic soil nitrogen and water infiltration in uncut and logged stands, outside and inside the fire perimeter. Subalpine fir recruitment was abundant in uncut, unburned, beetle-killed stands, whereas lodgepole pine recruitment was abundant in cut stands. Logging roughly doubled woody fuel cover and halved forb and shrub cover. Wildfire consumed all conifer seedlings in uncut and cut stands and did not stimulate new conifer regeneration within four years of the fire. Aspen regeneration, in contrast, was relatively unaffected by logging or burning, alone or combined. Wildfire also drastically reduced cover of soil organic horizons, fine woody fuels, graminoids and shrubs relative to unburned, uncut areas; moreover, the compound effect of logging and wildfire was generally similar to wildfire alone. This case study documents scarce conifer regeneration but ample aspen regeneration after a wildfire that occurred in the later stage of a severe beetle outbreak. Salvage logging had mixed effects on tree regeneration, understory plant and surface cover and soil nitrogen, but neither exacerbated nor ameliorated wildfire effects on those resources.

Salvage logging effects on regulating and supporting ecosystem services — a systematic map

“…Nonetheless, under some circumstances, salvage logging can meet both management and conservation objectives and address societal concerns. For example, salvage logging after bark beetle infestation of lodgepole pine forests in Colorado commonly reduces canopy fuels and regenerates new stands without negatively affecting native plant diversity or soil productivity (Collins et al 2011(Collins et al , 2012Fornwalt et al 2018;Rhoades et al 2018). As a consequence, controversy surrounding salvage logging among managers, environmentalists, politicians, and academics remains lively (Schiermeier 2016;Lindenmayer et al 2017;Müller et al 2018).…”

“…Some authors argue that ecological responses to salvage logging may result in synergistic effects due to the two successive disturbance events (the natural disturbance and then logging) occurring close in time (Van Nieuwstadt et al 2001;Wohlgemuth et al 2002;Karr et al 2004;Lindenmayer et al 2004;DellaSala et al 2006;Lindenmayer and Noss 2006). Others have found that environmental drivers other than salvage logging are more important in determining ecosystem regeneration (Kramer et al 2014;Peterson and Dodson 2016;Royo et al 2016;Rhoades et al 2018). Further, studies often report contradictory results, and there is currently no comprehensive, global assessment of the studies that have addressed salvage logging effects on ecosystem processes.…”

Salvage logging effects on regulating ecosystem services and fuel loads

“…; Rhoades et al . ). Regardless, salvage logging can generate trade‐offs between ecological and fuel‐reduction objectives; for example, reducing the amount of dead wood can help meet fuel‐reduction goals but eliminate important habitat features for certain taxa (Thorn et al .…”

Managing interacting disturbances: Lessons from a case study in Australian forests

“…Many forest ecosystems are subject to interacting disturbances that may affect ecological condition, biodiversity and ecosystem processes (e.g. Barlow et al., 2018; Cochrane & Barber, 2009; Rhoades, Pelz, Fornwalt, Wolk, & Cheng, 2018; Zald & Dunn, 2017). Mountain Ash forests are an example of such an ecosystem and work in them to date provides lessons for managing other highly disturbed forest ecosystems worldwide (Watson et al., 2018).…”