Vegetation map of the “Lindulovskaya Roshcha” nature reserve

The article presents the vegetation map of the “Lindulovskaya Roshcha” Nature Reserve (Fig. 1, 2), which is located in the Vyborg district, Leningrad Region (Karelian Isthmus). The reserve was organized in 1976 to protect the Lindulovskaya larch ship grove with the world’s oldest tree plantings. The idea of planting larch in the suburbs of St. Petersburg, necessary for the needs of shipbuilding, belonged to Peter the Great. However, it was possible to implement this project only in 1738, when the first planting of Siberian larch seeds collected in the Arkhangelsk region was carried out on ­agricultural land near the Lindulovka River (Roshchinka River at the present). There are 5 stages of larch planting in the reserve (Table 1). The age of the oldest plantings is 280 years, the youngest — about 40 years (see Fig. 4). Currently larch plantations occupy about 50 hectares. In addition to larch (Larix sibirica, L. dahurica, L. decidua) other tree species were planted in the 1920s: Pinus murrayana, Thuja plicata, Quercus robur, Ulmus glabra. In 1990 the “Lindulovskaya Roshcha” was included in the list of cultural heritage sites of UNESCO (“The historical centre of St. Petersburg and associated complexes of monuments”), as a place of growth of the oldest artificial plantations of larch in Russia and Europe. In order to study the patterns of distribution of plant communities, a vegetation map of the reserve was compiled for the first time on a scale of 1 : 50 000. 23 types of plant communities have been identified, of which 12 were natural and 11 were introduced (Fig. 3). The areal analysis showed that spruce forests occupy the largest areas (76 %), pine forests – 12 %, birch forests – 5 %; larch plantings account for 5 % of the territory (Table 2). Studies have shown that the species diversity of larch forests is much higher than in spruce stands, growing in similar conditions. The species composition of vascular plants of larch forests includes about 25–30 species, and in spruce forests – less than 10 species. It can be explained by the smaller closeness of larch stands compared to spruce ones and richer soils with a fairly powerful humus horizon. The vital condition of larch stands varies in plantings. On the one hand, this is due to the difference in the places of growth: in wetter habitats (on floodplain terraces) larch grows worse than on drained plains or valley slopes. On the other hand, the condition of larch stands is influenced by historical events and various planting methods. The deterioration of the condition of the larch was caused by military actions during the Second World War, when a large number of trees on the slopes of Roshchinka River valley were damaged and destroyed. In the post-war years, small areas were planted surrounded by spruce forests, which led to the fact that larch grew in less favourable conditions (competition from spruce increased) than earlier plantings on agricultural land or large cuttings.