Phytocoenological studies on floating-leaved anchored aquatic plants in Futouhu Lake, Hubei Province. II. The structure of Comm. Nymphoides peltata.
Monthly surveys conducted over a 1-year period were used to study the structure of Nymphoides peltata communities in Futouhu lake (Hubei province). Fourteen species were recorded of which N. peltata, Salvinia natans, Azolla imbricata, Trapa spp. and Zizania latifolia [Z. caduciflora] were the most frequently occurring, and Beckmannia syzigachne, Hydrocharis dubia, Lemna spp. Hydrilla verticillata, Potamogeton malaianus, P. crispus, Myriophyllum spicatum, Vallisneria asiatica and Ceratophyllum demersum were also found. There were 5 life forms and 11 growth forms. The community had zonation and patchy distribution, whilst N. peltata had a contiguous distribution. There was a 2-layered vertical structure of floating-leaved and submerged hydrophytes. There was no advanced hydrophyte layer over the water nor an advanced root or rhizome system below the substrate. N. peltata populations peaked in biomass and sexual reproduction in late May after which it declined and fluctuated around a low level. The replacement of one dominant species by another is evident in the community.