B. Papp szerk.: Studia Botanica Hungarica 33. 2002 (Budapest, 2002)

Bebya, S.: The fir forests of the Caucasus Mountains and considerations on their preservation

plex age structure of stands and the level of continuity in their development are the most important factors to assure the flourishing Abies forests of the Caucasus. For forest surveying works and for purposes of forestry it seems to be most appropriate to divide the complex stands of different age into three tiers, excluding saplings. The first, upper tier consists of the old-aged and mature stands. The second, middle tier consists of the middle-aged and developing stands. The third one is characterised by young trees. When surveying forests, the estimation indices must be stated separately for each tier. This method of forest surveying is very important for projecting economic measures and organising the rational use of the forests. In the Abies forests of the Caucasus mountains, the most important and actual tasks of modern forestry operations should be based on forest typology. The author, in cooperation with local experts, offers a complete classification of the Abies forest types of the Caucasus mountains for the first time. Using accepted ecological and genetical principles, this system of classification is based on the analysis of a large quantity of documentation and personal investigations, i.e. those conducted on typological test sites (BEBYA 2002). Taking into account the spatial and time factors of the development of forest associations, phases of association development have been drawn up beginning from common to particular (from an indigenous type of forest to a derived one) and from simple to complex (reforestation into initial type of forest). Phases of development define genetically related biogeocenotics (associations, fullness of stands). When these are taken together with the indigenous stands, they form a united biogeocenotic system. We recommend to unite the currently (locally) used forest types into natural groups of forest types. CONCLUSIONS AND RECOMMENDATIONS The multi-year investigation and the above outlined observations made it possible to work out a new classification of forest types for the Abies forests of the Caucasus. We distinguish the following Abies nordmanniana forest types: - festucosum; - luzulosum; - mixtaherbosum; - filicosum; - fir forests with evergreen Colchidean undergrowth; - fir forests with deciduous Colchidean undergrowth; - subalpine fir forests; and - rock forest complexes.