Landscape heterogeneity, i.e. the variation of ecological conditions in space and time, offers opportunities for ecological communities with various environmental requirements to co-exist at landscape level. Species turnover across spatial gradients (i.e. beta diversity) is considered a determinant of overall diversity of a landscape (i.e. gamma diversity, Tscharntke et al. 2012). In forest landscapes under natural dynamics, heterogeneity is provided and maintained by disturbances at different spatial scales such as forest fires, wind throws, and local-scale gap dynamics (Angelstam 1998; Kuuluvainen 2002, 2009; Bouget and Duelli 2004; Schütz et al. 2016). In contrast, landscapes that have been under intensive human use (production landscape), for instance in the European boreal and temperate forests, experience a simplification (homogenisation) of habitats at stand and landscape scales, threatening forest biodiversity (Kuuluvainen 2002; Kuuluvainen and Gauthier 2018). Fire suppression and the use of harvesting cycles (rotation length) shorter than tree life span have drastically reduced natural disturbances, while tree planting and seedling, tree selection and harvesting of timber (clear-felling or partial cuts) results in reduced tree species diversity and absence of important natural disturbance legacies (Bengtsson et al. 2000; Odion and Sarr 2007; Schütz et al. 2016). Consequently, managed forest stands, particularly in the clear-felling systems, lack important habitat features such as large old trees supporting micro-habitats (e.g. cavities) and large amount of standing and downed deadwood (Bouget et al. 2014; Juutilainen et al. 2014; Larrieu et al. 2017).
