Forest Biodiversity

Forests contain a large amount of terrestrial biodiversity and are considered important components of terrestrial ecosystems that provide several crucial ecosystem goods and services to humanity (Gamfeldt et al. 2013). Forest biodiversity encompasses not only trees but all life forms found within forest ecosystems. However, trees are essential elements of forests that cannot be replaced with any other elements. Trees, along with various other ecological variables, create ecological and physical variation in forests and provide food, shelter and living space for numerous organisms (Jones et al 1994). Trees provide a humid environment for understory plants, and their fallen leaves affect soil conditions and protect seeds, seedlings and soil organisms

2015) and insect herbivores (Castagneyrol et al, 2014). Gamfeldt et al. (2013) stated that tree species richness in boreal and temperate forests was positively affected by multiple ecosystem functions, such as tree growth, topsoil carbon storage, berry production, game production potential, the presence of deadwood and biodiversity in the understory. Therefore, knowing and conserving a variation of tree species in a forest is crucial to ensure a future potential of high levels of multiple ecosystem services (Gamfeldt et al. 2013).

Plant diversity maps play an outstanding role in effective management of and decision-making for vegetation landscapes. Thus, their significance is expected to be especially considered in forested areas by the forest managers because of the difficulty in managing and appreciating the diversity of forest trees (Foody and Cutler 2006). In particular, the concept of biodiversity as a primary principle should be considered during protection and conservation planning, management and utilization (Foody and Cutler 2006, Kiran and Mudaliar

2013), identifying prominent conservation areas (Carlson et al. 2007) and ecological restoration efforts (Champagne et al. 2004). Studies on the relationship between species richness and remote sensing data have increasingly used vegetation indices (VIs) and band combinations. It should be noted that the usage of NDVI in estimating species richness has increased. In a previous study, there was a positive correlation between plant species richness and NDVI both in temperate and tropical ecosystems (Gillespie et al. 2008). It has become possible to calculate species turnover or beta-diversity of an area using the spectral heterogeneity of remote sensing data (Rocchini et al. 2009). In this method, beta-diversity has been obtained using compositional and spectral similarity matrices among sampling plots (Rocchini et al. 2009, 2015). Generally, the similarity in species composition among pairs of sampling plots has been examined using the Sørensen index or the Jaccard index of sampling plots, and the spectral distance can be accessed using Euclidean distance (Rocchini et al. 2009, 2015). In this method, a large decay in the similarity of species among sites corresponds to high beta-diversity in terms of species composition (Rocchini et al.