This association includes open to closed stands of Lemna gibba, a tiny species freely floating on the water surface. Its stands are slightly shiny and lighter green than those of other lemnids. It occurs in eutrophic to hypertrophic water bodies, often with high concentrations of nitrogen, phosphorus, calcium, and even chlorides. In the Czech Republic it is most common in warm lowlands, but it tends to spread with increasing eutrophication, even to higher altitudes.