Aquatic communities in the British National Vegetation Classification system

This article gives an overview of the aquatic communities in the British National Vegetation Classification system.

Introduction
The aquatic communities of the NVC were described in Volume 4 of British Plant Communities, first published in 1995, along with the swamps and tall-herb fens.

In total, 24 aquatic communities have been identified.

The aquatic communities fall into the following six groups:
 * four communities of the water surface and sub-surface, in which duckweeds and/or Frogbit are the constant species; these communities (A1, A2, A3 and A4) are found in moderately-rich to eutrophic standing waters
 * eight free-floating or rooted and submerged, pondweed communities (A5, A6, A11, A12, A13, A14, A15 and A21)
 * six communities in which rooted water-lilies and pondweeds with floating leaves are the constant species (A7, A8, A9, A10, A19 and A20)
 * three communities in which water-crowfoots and/or starworts are the constant species (A16, A17 and A18)
 * two hairgrass and quillwort communities (A22 and A23)
 * a single community characterised by free-floating vegetation found in impoverished base-poor standing waters (A24).

List of aquatic communities
The following is a list of the communities that make up this category:
 * A1 Lemna gibba community Lemnetum gibbae Miyawaki & J. Tx. 1960
 * A2 Lemna minor community Lemnetum minoris Soó 1947
 * A3 Spirodela polyrhiza - Hydrocharis morsus-ranae community
 * A4 Hydrocharis morsus-ranae - Stratiotes aloides community
 * A5 Ceratophyllum demersum community Certaophylletum demersi Hild 1956
 * A6 Ceratophyllum submersum community Certaophylletum submersi Den Hartog & Segal 1964
 * A7 Nymphaea alba community Nymphaeetum albae Oberdorfer & Mitarb. 1967
 * A8 Nuphar lutea community
 * A9 Potamogeton natans community
 * A10 Polygonum amphibium community
 * A11 Potamogeton pectinatus - Myriophyllum spicatum community
 * A12 Potamogeton pectinatus community
 * A13 Potamogeton perfoliatus - Myriophyllum alterniflorum community
 * A14 Myriophyllum alterniflorum community Myriophylletum alterniflori
 * A15 Elodea canadensis community
 * A16 Callitriche stagnalis community
 * A17 Ranunculus penicillatus ssp. pseudofluitans community
 * A18 Ranunculus fluitans community Ranunculetum fluitantis Allorge 1922
 * A19 Ranunculus aquatilis community Ranunculetum aquatilis Géhu 1961
 * A20 Ranunculus peltatus community Ranunculetum peltati Sauer 1947
 * A21 Ranunculus baudotii community Ranunculetum baudotii Br.-Bl. 1952
 * A22 Littorella uniflora - Lobelia dortmanna community
 * A23 Isoetes lacustris/setacea community
 * A24 Juncus bulbosus community.