Implementation of the Classification System of Forest Habitats in Accordance with the 'Natura2000' Standards in the Georgian Legislation
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Implementation of the classification system of forest habitats in accordance with the 'Natura2000' standards in the Georgian Legislation Maia Akhalkatsi , Mariam Kimeridze Abstract Georgia is made up of two separate mountain systems: the Greater Caucasus lying between the Black and Caspian Seas; and the Lesser Caucasus, which runs parallel to the greater range. Two thirds of the country's territory (69700km²) is mountainous. One third of it is covered by forests, 70% of which are mountain forests spread from lower montane belt up to the treeline ecotone. The classification of forest plant communities was done by A. Dolukhanov (1989). However, the different methodology used by European and Soviet schools caused differences in nomenclature. Natura2000 habitat directives based on CORINE biotope classification system developed legislative basis for conservation of natural habitats in EU. To join this system it was necessary to conduct inventory and develop new schema of habitat types according to Natura2000 standards in Georgia. We have undertaken an attempt to classify Georgian forest area to the habitat types and have achieved the following results. 18 forest habitat types are identified to belong to the biogeographical region - Forests of Temperate Europe. Beech forest is represented by 7 types. 2 of which are characterized only for Georgia. 5 of 6 habitat types belonging to Mediterranean deciduous forests are typical only for the Caucasus. 1. Introduction Georgia is located in the Caucasus region, which is among the planet’s 25 most diverse and endangered hotspots designated as conservation priorities because the Caucasus is a region of remarkably rich vegetation with a very high level of endemism (Myers et al., 2000). Georgia has an extremely varied topography and climate that produce a mosaic of habitat types ranging from see level up to alpine vegetation near the snowline; and, from warm, humid lowlands at the Black See to dry, continental areas in the Eastern Georgia covered by forests of different kinds, steppes, and semi-deserts. 4,400 species of vascular plants, including 380 endemic species, occur in Georgia’s 69,700 kilometres2 (Nakhutsrishvili, 1999). The Caucasian mountain region is made up of three separate mountain systems (the Greater and Lesser Caucasus and Talysh mountains) and the lowlands of the Transcaucasian depression located between Black and Caspian Sees (Neidze, 2003). Georgian territory covers parts of the Greater Caucasus mountain range, Transcaucasian depression and the Lesser Caucasus Mountains, which run parallel to the greater range, at a distance averaging about 100 kilometres south, between 40º and 47º latitude east, and 42º and 44º longitude north. Two thirds of the country is mountainous with an average height of 1,200 m.a.s.l., with highest peaks of Mount Shkhara (5,184 m.a.s.l.) at the Western Greater Caucasus and Mount Didi Abuli (3,301 m.a.s.l.) in the Lesser Caucasus. Ilia State University, Institute of Ecology, Tbilisi, Georgia. [email protected], Georgian Society of Nature Explorers, "Orchis", Tbilisi, Georgia, [email protected] 6 The core of the Great Caucasus mountain range is composed of Precambrian and Paleozoic crystalline rocks, mostly granites and gneiss. The mountains of the southern macroslope are made of Jurassic and Triassic slates, sandstones, allevrolites, argellites, massive limestone and tuffs (Romanika, 1977). The Lesser Caucasus at Javakheti Plateau is composed of Upper Cretaceous and Tertiary igneous rocks including lavas and shallow intrusive rocks such as andesite, basalt and dolerite (Klopotovski, 1950). The soils of the southern macroslope of the Great Caucasus mountain range belong to the Western Transcaucasian Mountain Province (Ivanova et al, 1963). Within the lower vertical zone (up to 300-500 m above sea level), either mountain zheltozems or gray forest soils predominate. Higher, up to 1800-2000 m, the soils belong to the brown mountain-forests acid non-podzolized type. Most soils within the forest belt correspond to either Inceptisols or Ultisols. The Lesser Caucasus including Javakheti, Tsalka-Dmanisi and Erusheti uplands is covered with the mountain chernozems (which are formed at altitudes from 1200-2200m) and meadow chernozem-like soils. In highlands they are replaced by mountain-meadow soils. Besides, the alluvial soils, redzinas, brown as well as the meadow-brown soils occur here, with the predominance of brown forest type of soil in the mountain forest belt (Neidze, 2003). Climate is temperate but fluctuates by elevation, that varies from 0 to 5184 m (air temperature is changed on the average of 0.65 °C per 100 m altitude); and by regions from humid western Georgia to arid zones in the Eastern Iori Plateau (annual precipitation varies from 1500-2000 and up to 4500 millimetres in the western, Kolkhic part to 600-1000 mm in drier parts of eastern and southern regions; Neidze, 2003). One third of the Georgian territory is covered by forests, 70% of which are mountain forests spread from lower montane belt up to the treeline ecotone. The Caucasus forests have one of the highest levels of endemism in the temperate world (Kvachakidze, 2001). 23 percent of vascular plants are endemic to the region. According to Dolukhanov (2010) the Caucasus forest belt can be subdivided into three major elevation zones: broad-leaved forests (50-900 m), coniferous forests (900-1700 m), and high mountain krummholz forests (1700-2000 m). The overstory is frequently dominated by beech, hornbeam, chestnut, oak, and fir. Georgian vegetation is well studied by Georgian botanists (Grossheim et al., 1928; Ketskhoveli, 1959; Dolukhanov, 1989, 2010; Nakhutsrishvili, 1999, Kvachakidze, 2001, 2009). The classification of forest plant communities was done by A. Dolukhanov (1989). However, the different methodology used by European and Soviet schools caused differences in nomenclature. Natura2000 habitat directives based on CORINE biotope classification system developed legislative basis for conservation of natural habitats in EU. To join this system it was necessary to conduct inventory and develop new schema of habitat types according to Natura2000 standards in Georgia. We have undertaken an attempt to classify Georgian forest area to the habitat types. 2. Materials and Methods The classification of forest habitats of Georgia is based on the Interpretation Manual of European Union Habitats - EUR27. The "Habitats" Directive (Council Directive 92/43/EEC of 21 May 1992 on the conservation of natural habitats and of wild fauna and flora, O.J. L206) is a Community legislative instrument in the field of nature conservation that establishes a common framework for the conservation of wild animal and plant species and natural habitats of Community importance; it provides for the creation of a network of special areas of conservation, called 'Natura2000'. 7 The Directive is developed on the bases of CORINE biotope classification (1989, 1991) determining codes and habitat types of Europe, in particular involving the division of the latter into sub-types. According to Interpretation Manual habitat classification is based on plant community types. This information is obtained from literature data of botanists working in Georgia since 18th century (Grossheim et al., 1928; Ketskhoveli, 1959; Dolukhanov, 1989, 2010; Nakhutsrishvili, 1999, Kvachakidze, 2001, 2009; etc.). The description of each habitat types is composed by sections: 1) General description of distribution area and environmental conditions; 2) Species of plants including dominant, rare and endemic species; 3) Corresponding categories in other countries of Europe; 4) Associated habitats, which occupy adjacent territories; 5) Bibliography. 3. Results 24 forest habitat types are identified for Georgia (Table 1). 18 belong to the biogeographical region - Forests of Temperate Europe. 6 habitat types belong to Mediterranean deciduous forests. The main difference from the European habitats is existence of different dominant species of the plant community. Species composition on generic level is very similar, but on species level the Caucasus differs from European vegetation. There are species, which are related with European species but are endemics for the Caucasus: Abies nordmanniana, Picea orientalis, Pinus kochiana, Fagus orientalis, Quercus iberica, Betula litwinowii, etc. Beech forest group is represented by 7 habitat types. 2 of them: (1) Beech forests with Kolkhic understory (Fageta fruticosa colchica); and (2) Beech forests without understory (Fageta sine fruticosa) are characterized only for Georgia. 4 other habitats differ from European related habitat types (Table 1): 1) Dark-coniferous forest (Piceeta orientale-Abieta nordmanniana); 2) Pine forest (Pinus kochiana); 3) Yew forest (Taxus baccata); 4) Hornbeam forest (Carpinus caucasica). 5 habitat types of the Mediterranean deciduous forests are typical only for the Caucasus (Table 1). Most outstanding and typical only for Caucasus and namely Georgia are the following forest habitats: 3.1 Beech forests with Kolkhic understory (Fageta fruticosa colchica) The existence of the dense understory differentiates the beech forest of Georgia from the one in the rest of Europe. The beech forest with the Kolkhic understory (Fig.1) is the composing part of the ecoregion of Kolkhic mixed broad leaved forest. It is widespread in west Georgia on Northern-western slopes of Great Caucasus and the Ajara-Imereti Range. The climate is moist with about 2500 mm of annual precipitation.