Nature Protection and Plant Conservation in the Botanic Garden of Petrozavodsk State University
Volume 2 Number 10 - June 1998
A. Prokhorov & E. Platonova
For many centuries botanic gardens have contributed to the scientific and cultural development of society. The main aims were the introduction and cultivation of plants. More recently, they are concerned with the conservation of wild and cultivated plants.
The Botanic Garden of Petrozavodsk State University was founded in 1951 with an area of 370 ha. It is the only garden in the northern part of the middle taiga zone of European Russia Ä the most northern point where many trees have normal growth (34º24'W, 6lº51'N). The garden is rugged with an altitude of 0-90 m above the level of the Onega lake. The southern slopes provide a warmer microclimate. There is a beautiful view of Petrozavodsk from a point on the lake.
There is a cultivated plot of about 40 ha. Displays include an arboretum (trees and shrubs of Europe and Asia (Fennoscandia) and America), a herb section (medicinal plants, ornamentals) and nurseries for fruit trees, berry shrubs and ornamentals. The rest of the garden (about 330 ha) is native vegetation, forests, meadows, swamps and rocks Ä the typical Karelian landscape elements. Many species with ecotypes and forms occur in the area which provides an opportunity for research on the flora and vegetation.
Since 1994, the geological, geophysical, soil and botanical aspects of the site have been investigated thoroughly. It is a unique natural area showing the evolution from the early geologic time to the present day. It has remarkable natural rock features. The Quaternary period is shown by glacial and lake deposits formed during glacier melting and the latest fluctuation of the Onega lake level. A number of palaeo-seismo-variations have been detected from catastrophic earthquakes during the postglacial period. The soil types are uncommon for the middle taiga zone with intermediate podsol and brown soil patterns. The floral inventory included some relict and rare species of trees and shrubs.
Unusually, for the middle taiga zone ecological conditions exist for woodland species. This type of vegetation was widespread in the Karelia region 5-6 thousand years ago (Atlantic optimum period). In the garden area three types of Tilia cordata vegetation have been discovered and some other species of platyphyllous forests. Several lime trees in these areas are 20m high and the diameter of some trees is more than 80 cm which is unusual for the middle taiga zone. This is the northern limit for Tilia cordata and is a shrub.
The lime trees and the distinctive soils provides unusual conditions which gives rise to species diversity, and a predominance of woodland and forest species. Most common representatives of the woodland flora are Lathyrus vernus (L.) Bernh., Aegopodium podagraria L., Carex digitata L., Gagea minima (L.) KerÄGrawl., Campanula persicifolia L., Milium effusum L. Such woodland species as Ribes spicatum Robson, Paris quadrifolia L., Aconitum septentrionale Koelle, Viola mirabilis L. etc. were also identified. It also provide an ecological niche for rare Karelian species such as Brachypodium pinnatum (L.) Beauv. which is included in the Karelian Red Data Book (1995).
Interesting and unique areas are 'curly rocks'. As a result of glacial activity, tectonic movement and recent erosion many rocks have ledges and splits, which are the habitat for mosses, lichens and vascular plants. Tilia cordata occurs at the base. On the bright, upper, south exposed sites of rocks the following species from Karelian Red Data Book can be found: Origanum vulgare L., Dracocephalum ruyishiana L., Veronica spicata L. On the shady rocks, the ferns Woodsia alpina (Bolt.) S.F.Gray and Asplenium trichomanes L. were found and moss species, Tortula ruralis (Hedw.) Gaertn. et al., Rhacomitrium heterostichum (Hedw.) Brid., Leucodon sciuroides (Hedw.) Schwaegr. and Hypnum cupressiforme Hedw.
Another type of vegetation widespread in Karelia during Atlantic optimum period were alder forests with Alnus glutinosa (L.) Gaerth. dominant. At present A. glutinosa grows mainly in south Karelia and is classified as a relict plant. Alnus glutinosa occurs in the Garden on the boundary zones between grass swamps and the south slopes of terraced ridges. This habitat is characterized by stagnant water that causes the formation of tussocks. Several types of Alnus glutinosa vegetation have been detected in the Garden.
Other native rare plants found in the Garden are Epipactis palustris (L.) Crantz, Campanula latifolia L., Veronica beccabunga L., Delphinium elatum L. In total 9 species in the Karelian Red Data Book (1995) occur naturally in the garden. Some orchid species (Cypripedium calceolus L., Gymnadenia conopsea (L.) R.Br.) have been planted in the natural woodland areas. Furthermore, 11 species in the Karelian Red Data Book have been planted in the collection plots.
Work is in progress on plant records and mapping systems, and improved methods of management of the Botanic Gardens and Arboretum collection. A program for plant record database management for botanic gardens has been developed known as "Calypso". The principles of this program are the simplicity of data entry, compatible with the ITF (International Transfer Format), ease of data selection and the creation of catalogues, an index seminum and other standard outputs. This program can be adapted to the individual requirements of botanists and will be available also in an English version.
The Garden has a role as a collection of plants both in the natural habitat and in cultivation. The main task is conserving the biodiversity of the flora of North Europe flora by retaining the ecological balance and preserving both threatened individual species and ecosystems.