Six populations of Hippuris vulgaris L. localised in the spring rivers of Friuli Venezia Giulia (Italy) low-flood plain have been chosen for a synecological study aiming to understand the relationships between aquatic vegetation, chemical-physical parameters (of sediment and water) and human disturbance. Results revealed that, in spring water environments, H. vulgaris grows in dense populations favoured by low stream flow and its distribution and abundance is mainly influenced by water parameters such as temperature, conductivity and oxygen saturation. Moreover the studied populations seemed to be tolerant to the anthropic pressures observed in the examined sites, such as the increasing of nutrients supply due to the surrounding agricultural inputs, and the mowing of riverbed.