Changes in macroelement content in Nuphar lutea [L.] Sibith. and Sm. during the growing season

This study presents the results of monitoring studies carried out to determine the chemical composition of Nuphar lutea in two phytocoenoses of Nupharo-Nymphaeetum albae Tomasz. 1977 occurring in two lakes of different trophic types (eutrophic Lake Łaśmiady and oligo-humotrophic Lake Pływające Wyspy). The leaves (collected starting in May), rhizomes and roots of Nuphar lutea as well as water and sediment samples were collected from March to November in the above phytocoenoses (for 3 years in Lake Pływające Wyspy and for 4 years in Lake Łaśmiady). The samples were analysed for several parameters including: phosphate, nitrate, total nitrogen, potassium, sodium, calcium, total iron, sulphate and silica dissolved. In addition the manganese, cadmium, zinc and lead contents were determined in the leaves, rhizomes and roots of the plants collected in July (at the height of the growing season). It was found that the differences in the chemical composition of water and sediments between the lakes studied were more pronounced than in the case of leaves, rhizomes and roots of Nuphar lutea.