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).
Read more about this topic: Aquatic Communities In The British National Vegetation Classification System
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