Rare and protected species in the drainage ditches and adjacent phytocoenoses in the Polesie National Park

This paper presents the results of a floristic study conducted in the years 2003 - 2005 within the area of the Polesie National Park and its protective zone. Floristic inventories were carried out in twelve 100-metre-long sections of the drainage ditches and adjacent phytocoenoses and based on them office analyses of the flora were performed. The aim of the study was to determine the share of species with special natural values in the drainage ditches, taking into account the occurrence of legally protected, rare and endangered taxa at the regional level, in Poland and in Europe. The share of these species was also compared with the richness of special concern plants noted in the phytocoenoses adjacent to the investigated ditches. Based on the floristic composition, an analysis was made of the occurrence of taxa whose number of stands shows a declining trend compared to the Polish flora. The number of vascular plant species found in the ditches and in their vicinity was similar, but the low values of the similarity index suggest differences in the species composition of these habitats, which results in greater species diversity. The presence of special concern plants in the drainage ditches suggests that they are valuable habitats for the Polesie National Park. They create niches for rare, protected and endangered species