In terms of plant mass, the dominant species were the hydrophyte Ceratophyllum demersum (17.2 RPM%) and the helo-phyte Phragmites australis (17.0%) (Fig. 2). The hydrophyte Myrophyllum spicatum (4.9%) and the helophyte Carex acuta (8.2%) were subdominant. Other abundant species include the hydrophytes Lemna minor, Spirodela polyrhiza, Potamogeton pecti-natus, and algae filamentosae with the RPM% 2.1–3.9% and helophytes Typha angustifolia, T. latifolia and Calystegia sepium with 3.0–4.2%.