Scientific name Apium nodiflorum – Rorippa nasturtium-aquaticum agg. aquatic community
Common name Fool’s-water-cress – Watercress aquatic community
Community code FW2E

 

FW2E map: Apium nodiflorum – Rorippa nasturtium-aquaticum agg. aquatic community

Download full pdf synopsis: FW2E

 

Vegetation

This is a rather variable community of watercourses in which a variety of species can dominate. However, Apium nodiflorum and Rorippa nasturtium-aquaticum agg. are constants here and lend a strong forb element to the rather diverse marginal/emergent vegetation which also frequently includes Phalaris arundinacea, and occasionally Agrostis stolonifera, Sparganium erectum, Veronica beccabunga, Oenanthe crocata, Menta aquatica, Epilobium hirsutum, Solanum dulcamara and Sparganium emersum. Ranunculus penicillatus is a frequent species of the channel which can dominate. Other floating plants include Glyceria fluitans, Lemna minor, Callitriche stagnalis and Callitriche platycarpa. The bryophyte element here usually consists of Leptodictyum riparium, Fontinalis antipyretica and Rhynchostegium riparioides.

 

Ecology

This is a community typical of fast-flowing rivers and streams in the lowlands, with fairly base-rich and nutrient enriched waters.

 

Sub-communities

No sub-communities are currently described.

 

Similar communities

This community is related to both FW2C and FW2D. It differs from both in its greater component of marginal and emergent vegetation, particularly the abundance of Rorippa nasturtium-aquaticum agg., and its lower of frequency of Ranunculus penicillatus.

 

Conservation value

Almost all examples of this community with a relative abundance of crowfoots (Ranunculus spp. subgenus Batrachion) correspond with the EU HD Annex I habitat 3260 Floating river vegetation.

 

Management

This community may be affected by eutrophication, river engineering including dredging and canalisation, and trampling from livestock with access to the bankside.