Aquatic plants are key ecological components of standing water systems and reflect environmental conditions.  The British statutory nature conservation agencies Natural England (previously English Nature), Scottish Natural Heritage and the Countryside Council for Wales, and their fore-runner the Nature Conservancy Council, have carried out extensive surveys of aquatic vegetation, and use knowledge of plant communities to underpin nature conservation strategies for fresh waters.  The same is true of the Northern Ireland Environment Agency (previously the Environment and Heritage Service).  Plant assemblages and rare plants are used in the selection of statutory sites of national and international importance for wildlife, and macrophytes are also used in classifying the ecological condition of water bodies under the EC Water Framework Directive.

This Fact File is a compendium of information on aquatic macrophytes in England, Scotland and Wales, drawn from a wide range of sources and intended as a resource for nature conservation practitioners.  Much of this information is constantly under review, especially by the statutory conservation agencies.  Consolidating all this information into a single, publicly accessible computer file makes it available as a comprehensive document that can be searched, cross-checked and updated when necessary.  Most of the material in this Fact File is taken from existing books, reports, scientific papers and web sites.  It draws heavily on the New Atlas of the British and Irish Flora (Preston et al., 2002a) and material on the Joint Nature Conservation Committee (JNCC) web site.

This Fact File covers macrophytes of fresh and slightly saline standing waters in Britain.  These include lakes, lochs, pools, meres, brackish lagoons, reservoirs, gravel pits and ponds.  Flowing water vegetation is not covered specifically, but most standing water plants also occur in rivers.  The species included are submerged, floating and emergent vascular plants, a few aquatic bryophytes and all the charophytes.  Aspects both of individual species and of plant communities are discussed.  Check lists of native and introduced aquatic species have been drawn up and annotated with legal designations, status and distribution.  An overview of vegetation classifications is given, and summaries are included of site evaluation and monitoring methods involving aquatic vegetation.

Reference is made to domestic and European legislation on nature conservation, including the Water Framework Directive.

As new plant records accumulate and as policy and legislation change, some of the information presented here will become obsolete or out of date.  It is envisaged that the Fact File will be updated periodically, to keep abreast of these changes.