Watercourses characterised by floating or submerged vegetation form a priority habitat of international importance, and are listed on Annex II of the Habitats Directive. The riverine plant communities occurring in the UK are important in a European context and provide good examples of the range of river types and variability of associated plant communities.

The definition of watercourses characterised by Ranunculion fluitantis and Callitricho-Batrachion vegetation is very wide, in practice covering the majority of streams and rivers with aquatic plant communities of note. This is reflected in the wide range of rivers in the UK that have been proposed for designation as Special Areas of Conservation (SACs) for this feature.

Aquatic plant communities comprise a significant component of the physical and biological diversity, habitat structure and ecology of river channels, providing habitat and food for a range of species, particularly invertebrates and fish. Aquatic plants also influence and modify flow, and nutrient and sediment dynamics.

Concern has been increasing about recent declines in aquatic plant diversity in European rivers. This has been attributed to a number of factors, including nutrient enrichment, siltation, low flows arising from drought and abstraction of groundwater, and unsuitable management practices. Consequently, there has been a rapid decline in many of the plant species associated with this habitat, including Potamogeton spp., Groenlandia densa, Oenanthe fluviatilis and Ranunculus spp.

Ecology of Watercourses Characterised by Ranunculus fluitantis and Callitricho-Batrachion Vegetation

Monitoring Ranunculus fluitantis and Callitricho-Batrachion Vegetation Communities

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