This vegetation type is dominated by Potamogeton nodosus, a species which possesses both natant and submerged leaves, but the former may be absent in flowing water and the latter in warm, still, turbid water. It occurs in slow-moving rivers, artificial channels or flooded sand pits, but is absent from fishponds. These habitats are usually in an early successional stage or frequently disturbed, with mineral rather than organic sediments on the bottom. Water depth is usually between 30 and 60 cm. It is a rare vegetation type in the Czech Republic, occurring mainly in some sections of lowland river corridors.