Geology & Natural History
The area is composed mostly of Tertiary sediments (clay, marl, sandstone) and Quaternary volcanic bedrock (andesite, basalt, dolerite), with plateaux of petrified lava flows. There are 30 mineral springs, of which Zvare, Mitarbi and Nunisi are supposed to have medicinal properties, in addition to Borjomi water. The climate is moderately humid, with cold snowy winters and long cool summers, lasting 3,5 months below 1,100m and just two months above 1,500m, where snow lies for at least 150 days a year. Average precipitation is 687mm a year, although it's higher to the north with 1,842mm at the Rikoti Pass and 1,366mm at Kharagauli, and lower to the south with 576mm at Atskuri. Temperatures are also higher to the north, with an average in August of 23°C at Kharagauli, 19° at Borjomi and 16° at Bakuriani.
Forest covers 75% of the national park, mostly climax conifer forest. However- more than 60 species of Colchic trees and shrubs have been recorded here, including cherry-laurel, holly, chestnut, Rhododendron ponticum, yew and buckthorn. For dominated by oak (Quercus iberica), beech (Fagus orientalis) and hornbeam (Carpinus caucasica) can be found at up to altitudes of 1,800m, though most у lower altitudes, while spruce (Picea orientalis) and pine (Pinus kochiana) can be found from 1,000m to 1,800m, and Caucasian fir (Abies nordmannia) from 1,400m 1 800m. From this altitude to 2,400m there's subalpine forest of crook-stem birch (Betula litwinowii), mountain ash (Sorbus caucasigena) and Rhododendron Caucasicum, with alpine grasslands above 2,400m. To the south, the slopes of the Trialeti are dominated by the pine Pinus sosnowskyi with smaller species such juniper. Astragalus caucasicus, meadow sweet, hawthorn, cornelian cherry and dog-rose. In addition the Nariani marshes, at 2,050m, are home to many wetland species.
The 55 species of mammal in the national park include red and roe deer, chamois, brown bear (Ursus arctos), wild cat, lynx, wolf, boar, badger, otter, pine marten, squirrel and some endemic species of bat (Myotis emarginatus, Nyctalus lasiopterus, Barbastella barbastellus). Nine bezoar goats (like small ibex) were reintroduced to the Atskuri section of the park in 2006.
Among the 95 species of bird are the golden and white-tailed eagle, black vulture, blackcock, crossbill and six types of woodpecker. There are also snakes, three endemic lizards, newts and Caucasian salamander.