The effects of physical-chemical water parameters on the Nymphaeion alliance development in northwestern Serbia

Nymphaeion alliance vegetation is dominant floating-leaved vegetation in the Danube–Tisza–Danube hydrosystem in northwestern Serbia and comprises Nymphaeetum albae, Nymphaeetum albo-luteae, Nymphoidetum peltatae and Trapetum natantis associations. Comparative analysis of physical-chemical water parameters on localities where these – in most parts of Europe endangered and vulnerable stands – develop showed that most phytocenoses are associated with specific habitat conditions. Of the analyzed water properties, the factors that cause Nymphaeion alliance phytocenoses differentiation are primarily pH, alkalinity and COD-MnO4. Formation of the Nymphaeetum albae stands is significantly associated with the highest values of pH, COD-MnO4 and alkalinity, and the lowest nitrate, nitrite, dissolved and the total phosphorus content values, in comparison to the other studied associations. Nymphoidetum peltatae stands develop in waters characterized by the lowest pH and COD-MnO4, low alkalinity, and the highest nitrate and nitrite values in relation to the other analyzed phytocenoses. Trapetum natantis stands, on the other hand, prefer the warmer sections of the canal network, neutral pH, and the highest values of BOD5, dissolved and total phosphorus. Habitat conditions in which Nymphaeetum albo-luteae stands develop are of the widest range in comparison to other investigated phytocenoses