Effectiveness monitoring for biodiversity: comparing 15 year old structural retention harvest areas to fires in boreal aspen

Abstract

Convergence of species composition in regenerating harvested areas and naturally disturbed forest is a critical component of forest management modeled after natural disturbances. We assessed convergence of birds, plants, and habitat structures in aspen (Populus tremuloides) stands harvested with structural retention by Alberta-Pacific Forest Industries Inc. (Al-Pac) 15 years ago with similar aged fire area, and examined a chronosequence of younger and older burned aspen stands from Alberta Biodiversity Monitoring Institute (ABMI) sites. Most habitat structures and many bird and plant species in the 15 year harvest areas were at levels similar to 20-40 year or >40 year fire areas. Snags, moss, and lichen cover, and a few groups of species were at lower levels in the harvest areas than comparable aged fire areas or older stands. Agglomerative clustering showed the plant community to be most similar to >40 year burned stands, with the bird community intermediate between >20 year and <20 year fire areas. A novel likelihood-based analysis of species estimated the 15 year harvest areas to have a community similar to forest sites with 36.8% human footprint, indicating substantial recovery of the harvest areas. Harvesting aspen stands with structural retention appears to be effective at allowing most biodiversity components to recover rapidly.Résumé : La convergence de la composition en espèces entre des forêts régénérées à la suite de coupes et de perturbations naturelles est une composante essentielle de l'aménagement forestier fondé sur les perturbations naturelles. Nous avons évalué la convergence des oiseaux, des plantes et de la structure des habitats entre des peuplements de peuplier faux-tremble (Populus tremuloides Michx.) ayant subi une coupe avec rétention structurelle par la compagnie Alberta-Pacific Forest Industries Inc. (Al-Pac) il y a 15 ans, des feux du même âge et une chronoséquence composée de peupleraies plus jeunes et plus vieilles dans des stations de l'Institut de surveillance de la biodiversité de l'Alberta. La plupart des structures d'habitat et plusieurs espèces d'oiseaux et de plantes des aires de coupe âgées de 15 ans étaient à des niveaux similaires à ceux de feux de 20 à 40 ans ou de plus de 40 ans. Les chicots, le couvert de mousses et de lichens et quelques groupes d'espèces étaient à des niveaux plus bas dans les aires de coupe que dans les feux du même âge ou plus vieux. Une classification ascendante hiérarchique a montré que la communauté végétale des aires de coupe s'approchait davantage de celle des aires brûlées de plus de 40 ans alors que la communauté d'oiseaux occupait une place intermédiaire entre les feux de plus et de moins de 20 ans. Une nouvelle approche d'analyse des espèces fondée sur la vraisemblance a estimé que les aires coupées il y a 15 ans ont une communauté similaire à celle d'une station forestière comportant 36,8 % de perturbation humaine, ce qui indique un rétablissement substantiel des aires coupées. La coupe avec rétention structurelle de peupleraies semble effi...

Quantifying Long-Term Bird Population Responses to Simulated Harvest Plans and Cumulative Effects of Disturbance

“…Apart from varying size, shape, distribution and location, our harvest areas were all assumed to be clear-cuts based on the harvest practices modeled by our SDMs. Other EBM-based practices in Canada like partial cuts, shelterwood cuts, structural retention, and understory protection have been studied throughout Canada for their effects on tree mortality (Thorpe and Thomas, 2007), subsequent tree growth (Montoro Girona et al, 2017, 2019, understory protection (Burke et al, 2008), and biodiversity (Fenton et al, 2013;Huggard et al, 2014;Charchuk and Bayne, 2018). These harvest strategies may be more appropriate than traditional clear-cuts for emulating natural disturbance in regions where forest fires are less frequent than insect outbreaks and other disturbances.…”

“…Fragmentation by roads and other linear features (e.g., pipelines, seismic lines, power transmission lines) are also a concern if these features reduce forest patch size or increase edge effects (DeLong and Tanner, 1996;Dyer et al, 2001Dyer et al, , 2002Schneider, 2019). To reduce such effects on wildlife, many forestry companies have begun adjusting the spatial pattern, size distribution, and timing of harvests to better approximate natural disturbances like forest fire (Hobson and Schieck, 1999;Huggard et al, 2014). The goal of approximating natural disturbance is that it provides a coarse-filter approach that should be better at maintaining habitat for more wildlife species than traditional harvesting (DeLong and Tanner, 1996;Dzus et al, 2009;Kuuluvainen and Grenfell, 2012).…”

“…It is becoming increasingly evident in western Canada that harvest and forest fires jointly affect forest age and the habitat available to different birds, despite best efforts at suppressing fire (Arienti et al, 2006). Furthermore, there is good evidence that bird abundance often differs between recently burned and recently harvested forests (Hobson and Schieck, 1999;Schieck and Song, 2006;Robertson and Hutto, 2007), particularly in the first 10-20 years post-disturbance (Schieck and Song, 2006;Huggard et al, 2014). Fires leave snags and patches of unburned vegetation and create temporary habitats for some species like woodpeckers and flycatchers (Schieck and Song, 2006) and some of these habitat attributes may be absent from some types of harvest blocks (Huggard et al, 2014).…”

“…Furthermore, there is good evidence that bird abundance often differs between recently burned and recently harvested forests (Hobson and Schieck, 1999;Schieck and Song, 2006;Robertson and Hutto, 2007), particularly in the first 10-20 years post-disturbance (Schieck and Song, 2006;Huggard et al, 2014). Fires leave snags and patches of unburned vegetation and create temporary habitats for some species like woodpeckers and flycatchers (Schieck and Song, 2006) and some of these habitat attributes may be absent from some types of harvest blocks (Huggard et al, 2014). Whether or not there are significantly large differences in responses by species to fire and harvest in meaningful space and time remains a key question (Andison, 2003;Messier et al, 2003).…”

Islands – Soil Patches and Plant Community Dynamics on a New Oil Sands Reclamation Design

“…The Islands approach builds off past reclamation research (e.g., Burley et al, 2005) as well as from boreal forest management practices which leave residual patches (islands) of forest in harvested areas (e.g., Baker et al 2015;Gustafsson et al, 2015) and natural disturbances, such as fire, which also leave unburnt portions of forest (e.g., Huggard et al 2015;Delong and Tanner, 1996). These residual patches have substantial benefits to biodiversity by serving as lifeboats or colonization centres for species to be retained in the post-disturbance forest and by facilitating reestablishment of species into the surrounding area (Vanha-Majamaa and Jalonen, 2001).…”