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Phytosociological analysis of non-forest communities was carried out on one of the oldest and the biggest military training grounds in Europe, located near the city of Toruń, in central Poland. Heaths and psammophilous grasslands developed here as a result of deforestation of inland dunes in the valley of the Vistula River, as well as a result of destruction of soils and vegetation brought on by manoeuvres and artillery firings. They form a landscape mosaic with young self-seeding pines, mature pine forests and birch forests. Using the Braun-Blanquet method, 84 relevés were made in the areas dominated by dwarf shrubs and 32 relevés within psammophilous grasslands. Applying the classic phytosociological method, the following plant associations were distinguished in the first set of relevés: Pohlio-Callunetum and Arctostaphylo-Callunetum, as well as the community with Cytisus scoparius. Within the psammophilous grasslands, two associations were distinguished: Spergulo vernalis-Corynephoretum and Calamagrostietum epigeji. In this paper, the heterogeneity within associations and communities was presented together with descriptions of individual syntaxa, as well as dynamic and developmental relationships between the aforementioned were identified.

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In many ecological studies the theory prevails that the increased human economic activity can lead to simplification of species composition of phytocoenoses and a decline of their species diversity. However, there are also other views on this issue. Therefore, an attempt was undertaken to verify these contradictory opinions. The research was conducted at three sites characterised by a diversified and intensified land use form (the nature reserve, 50 year-old poplar plantation and a grassland). The results from the nature reserve were compared with the data for 1963-1965 when other plant communities dominated in the reserve. The results of field observations collected in the form of relevés were used to assess the number of species, α-species diversity of phytocoenoses and ß-diversity. The largest number of species was found in the meadow, a fewer species were recorded in the reserve and the fewest in the poplar plantation; whereas the average number of species per relevé and the differences between the sites were minor. The species heterogeneity index varied within the range of 3.11-3.36, whereas the extreme differences were recorded in the reserve between the current results and the results from the 1960s. The studied phytocoenoses differed mostly in ß-diversity. The average index for the poplar plantation was lower than mean values of indices recorded in communities of the riparian forest and meadows. The obtained results support the opinion about non linear correlation between the increased disturbances and the decline of species richness and species diversity in phytocoenoses.