The species richness of the flora of selected sections of the Mietiułka River in the Polesie National Park

The aim of the study was to conduct an environmental evaluation of 6 selected sections of the improved Mietiułka River, which included an inventory and analysis of the vascular flora associated directly with this watercourse. The results of the study have shown that the flora of the study area is diverse in taxonomic, syntaxonomic and ecological terms, and that it comprises both typical aquatic plants and species characteristic of the habitats surrounding the river. In the flora found in the study sectors, a total of 114 vascular plant species was identified, which come from 42 botanical families, 15 syntaxonomic classes and belong to different ecological groups. Hemicryptophytes, spontaneophytes, species neutral to continentality as well as species included in the phytochorion with boreal elements: Euro-Siberian subelement, were clearly predominant in the species composition of the flora of all the study sectors. The macrophytes commonly found in Poland had the largest proportion. One species with a small number of stands in the country – water dropwort (Oenanthe fistulosa) – as well as two species threatened with extinction, Sagittaria sagittifolia and Hypochoeris glabra, were recorded.