Luc Sirois's research while affiliated with Université du Québec à Rimouski UQAR and other places

... The boreal forest has been changing in tree dominance from coniferous to broadleaf deciduous forests due to natural and anthropogenic disturbances (Baltzer et al. 2021;Laquerre et al. 2009;Marchais et al. 2020). These changes in turn affect understory composition and dynamics (Barbier et al. 2008). ...

... Forests globally are increasingly vulnerable to ecological transformation due to changing climatic conditions that simultaneously increase wildfire activity (4-7) and alter key postfire demographic rates such as seedling establishment (8,9), a phenomenon broadly termed "interval squeeze" (10). Declines in tree recruitment have been observed globally, causing widespread concerns about forest loss following wildfires and other disturbances (1,3,(11)(12)(13). ...

... We worked in a 170-km 2 study area surrounding Canadian Forces Station Alert, Ellesmere Island, Nunavut (82°30′N, 62°20′W; Fig. 1a). The landscape encompasses multiple hills and creeks, four lakes, and several ponds 33 . With only 156 mm of precipitation per year on average, and temperatures reaching − 40 °C in winter, the environment is a polar desert 33 . ...

... Despite a growing consensus that forest management aiming to conserve biodiversity should be based on the spectrum of disturbance variability (time interval, size, severity) produced by natural regimes (Gauthier, 2009;Kuuluvainen, 2002;Puettmann et al., 2012), clearcutting remains the dominant harvesting approach in boreal forests (Kuuluvainen and Gauthier, 2018;Boucher et al., 2021). These intensive cuts produce complex impacts on species assemblages, including bryophyte communities (Caners et al., 2013b;Paquette et al., 2016). ...

... Such changes are made by introducing missing main species into low-value stands (Pavlenko 1967;Izyumsky 1978;Krachkovsky 2014). Others meant a set of measures to transform even-aged single-layer stands into uneven-aged multilayer ones (Loewenstein 2005;Kerr et al. 2010;Dupont-Leduc et al. 2020;Schneider et al. 2021). Still others identified the conversion as an improvement of the stand resilience by introducing other valuable species into the pure stand (Heinze et al. 2000;Fonder 2007;Felton et al. 2010Felton et al. , 2016Dobrowolska et al. 2021). ...

... Afterward, others forest companies have actively harvested the study area. The Price Brothers & Company archives contain forest inventory plots, forest maps and extensive information about past forest management, dating back to the early twentieth century until c. 1960s (Boucher et al., 2009;Delisle-Boulianne et al., 2011;Elzein et al., 2020;Gérin et al., 1944). Data on more recent (>1960) forest conditions and management activities are available from the Government of Quebec archives. ...

... Lattice-based models are frequently used to describe vegetation dynamics. These models include tree-based and plant-based gap modelling in which seed and seedlings compete for a gap in a mature vegetation cover (Coffin and Lauenroth, 1990;Elzein et al., 2020;Kellomäki and Väisänen, 1991;Morin et al., 2020;Peters, 2002;Reynolds et al., 2001). When these models are applied to multiple species, they may generate insight into the factors affecting species dominance and diversity. ...

... However, this policy may extend the recovery period of secondary forests due to lacking natural regeneration of dominant tree species, increase their total area and consequently, vitiate the purpose of the NFPP policy (Zhu 2002;Liu et al. 2018). Selective logging, an effective method of sustainable forest management (Qi et al. 2016), considers both the harvest of forest resources and the promotion of secondary forest regeneration by regulating logging intensities (e.g., Knapp et al. 2017;Zhang et al. 2018;Sukhbaatar et al. 2019;Gagné et al. 2019). This is because after logging or creating a gap, environmental factors are modified, including soil temperature and nutrient availability, and particularly the incident light reaching the understory Lochhead and Comeau 2012;Olson et al. 2014). ...

... Variability in plant species diversity is an outcome of species interaction with particular set of environment variables either abiotic and biotic [102,103], which can occur in both space and time [104,105]. The concept of changing species composition and vegetation continuum along the ecological gradients emerged as an antithesis model for distinct units [106,107]. ...

... Deer control measures would then be needed to enable cedar regeneration to escape deer reach, but we do not know how fast cedar can respond to a reduction in browsing pressure in natural conditions. In contrast with the slow growth in the understory, a height of 3 m has been reached in some plantations in as little as 9 years, leaving a third of tree height out of reach for deer [25]. ...