Spatial Organisation of Forest Ecosystems in the Context of the Tembotov Altitudinal and Zonal Structure of Caucasian Landscapes

In this article, we compared cartographic distribution models of Caucasian forest-forming species with detailed ground-based data from the Tembotov system of altitudinal and zonal structure of Caucasian landscapes. Such verification allows us to assess the predictive ability of species distribution models, as well as to clarify the issues of localisation and fragmentation of forest belt in the Caucasus. The cartographic models of spruce, fir, beech and hornbeam distribution mainly corresponded to the actual localisation of dark coniferous and deciduous forests by and within the variants of vertical zonation of the Tembotov system. Climate humidity, topography, competition from other forest forming species and anthropogenic practices (deforestation, ploughing) determined the predicted and actual distribution of Abies nordmanniana (Stev.) Spach, Picea orientalis (L.) Peterm., Fagus orientalis Lipsky and Carpinus betulus L. throughout the Caucasus. Under suitable water regime, spruce, fir and beech forests can cover areas that are actually occupied by chestnut, oak and pine stands or ploughed. Hornbeam forests occupied relatively gentle, low-lying and arid areas, often disturbed by logging.