The aim of the research was to explore a new locality of Galeopsis angustifolia (Lamiaceae), a rare taxa in Poland. The floristic composition of a plant community with G. angustifolia was determined. The species was recorded along the railway line from Pyrzyce to Stargard Szczeciński, near to the railway station in Okunica village, not used since 2004. Currently, the plant community with G. angustifolia occupies a transect >300 m in length. It is also sporadically found in the areas adjacent to the railway line. The species penetrates into ruderal communities from the Artemisietea vulgaris class and creates plant communities with Galeopsis angustifolia, a dominant species in the patches. Synanthropic species, e.g., Rubus caesius, Convolvulus arvensis, Senecio viscosus, meadow species, e.g., Arrhenatherum elatius, Potentilla reptans, Pastinaca sativa, and mosses of dry and rocky habitats also form plant communities with Galeopsis angustifolia. Keywords rare species; Galeopsis angustifolia; railway areas; plant communities IntroductionRailway lines create specific environmental and soil conditions for plant growth. Species growing in these biotopes have distinctive ecological features; they are tolerant to excessive light, temperature fluctuations, resistant to the strong effect of precipitation, frost, erosion, wind, and air movement initiated by passing trains [1]. Despite harmful abiotic factors, railway lines create a habitat for many plant species from different ecological groups. Wildlife developed along railway lines has been the object of interest of many naturalists for many years. A lot of attention has been dedicated to flora growing in railway areas [2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21], including rare and protected plant species growing along railway embankments [22][23][24][25]. Galeopsis angustifolia from Lamiaceae is one of the rare species that grows in railway habitats in Poland [26,27].Galeopsis angustifolia (Ehrh.) Hoffm. is an annual plant with a height of 10-40 cm and a grey-hairy stem, without firm bristles near the nodes. It is characterized by lance-shaped or narrow lance-shaped leaves and by entire or softly corrugated leaf margins with 4 pairs of teeth at the most. The flowers are small (15-25 mm), with a red-violet perianth, gathered in pseudo-whorls. The calyx is very hairy, usually without glands, with visible veins in the lower parts and three times shorter than the corolla. The fruit is an ovoid nutlet which contains numerous seeds. It blooms from June till October [28,29]. According to the ecological indicator values, this species prefers warm regions and microhabitats (T = 5-4), and it grows in full light (L = 5). It is adapted to dry places (W = 2), rich in calcium carbonate (R = 5), poor in nutrients (Tr = 2) and organic matter (H = 2), scree and gravel [27].

Asclepias syriaca L. is on the invasive species list in Poland. Its sites are scattered, with the exception of cultivation sites; they are also not well identified in the country and that is why they have not been presented in the ATPOL (Distribution Atlas of Vascular Plants in Poland) yet. In this study, spatial structure of A. syriaca population against phytocenotic and soil conditions in Widuchowa (West Pomerania) were examined. Number of specimens, their density per 1 m 2 , and mean crowding were determined. In addition, the population spatial structure type was identified through observations and by calculation of the dispersion coefficient. On the basis of the conducted research, it was found that the investigated population comprised 1 500 specimens and occupied the area of 38 m 2 . It exhibited regular spatial distribution type (dispersion coefficient<1) and was characterized by high value of mean shoot density, which amounted to 29 spec./1 m 2 (max. 35 spec./1 m 2 ). On the basis of the conducted chemical analysis of the soil from the A. syriaca habitat, the substrate was classified as alkaline soil (pH=7.3-7.6), of low total nitrogen (0.07-0.15%), as well as low total carbon content (0.8-1.45%).

The differentiation of vegetation and flora of the upper Płonia R. valley in Western Pomerania was discussed in relation to distribution of components of natural environment. Causes of landscape transformation and direct types of human impact on vegetation were analysed. The obtained results have shown trends in the transformation of the valley's landscape, which can be summarised as a continuous change from anthropogenic agricultural landscape to a more natural one. It was concluded, that uncontrolled continuation of the recorded processes will lead, among others, to the decrease in biodiversity. For that reason a proposal for integrated landscape and nature management has been elaborated. It combines classical methods of protection (establishment of protected areas) with administrative and managerial measures, such as active management of biotopes outside the reserves and co-operation with non-profit organisations, in achieving protection goals at the scale of the whole landscape