Freshwater habitats
Freshwater habitats include both flowing and standing waters.
The UK has a great variety of running waters, from fast-flowing
upland rivers, to chalk streams in the south-east and slow-flowing
rivers of eastern England. Standing waters are similarly diverse,
ranging from small mountain corrie lochs to lowland ponds, large
lakes and reservoirs, and include four Priority Habitats under the
UK Biodiversity Action Plan:
The diversity of habitats within and around fresh waters
support a wide variety of species. Furthermore, freshwater habitats
can provide valuable green corridors for wildlife in an often
intensively developed urban or agricultural landscape.
Fresh waters are adversely affected by a number of human
pressures, including:
- Excessive groundwater and surface water abstraction.
- Pollution, especially eutrophication and acidification.
- The effects of inappropriate land-use or poor management, for
example afforestation, land drainage and overgrazing.
- Introduction of invasive plant and animal species.
- Urban, industrial, and agricultural development within
catchments.
- Inappropriate development of recreation and navigation.
- Inter-basin water transfer schemes and the construction of dams
and reservoirs.
Effective conservation of freshwater resources requires
integrated catchment management, involving a mixture of
environmental incentives, statutory controls, educational
initiatives and guidelines. For example, agri-environment schemes
may reduce the potential for nutrient enrichment from agricultural
runoff; sites can be designated for protection under international
conventions and Directives (such as the Habitats Directive); and
codes of practice such as the Forests and Water Guidelines aim to
reduce damage to freshwater habitats.
The Water Framework Directive (WFD) is a major piece of new
legislation whose principal objective is to ensure that all surface
waters attain good ecological status by 2015. The Directive's
stated aim is to establish a framework for action in the field of
water policy in order to protect inland surface waters,
transitional waters and groundwaters, and to promote sustainable
water use based on the long-term protection of available water
resources. The European Directive was transposed into UK law in
2003.
The JNCC plays a key role in the development of guidance,
collation and dissemination of data and information and in the
provision of advice on national and international freshwater
conservation issues. The
Freshwater Lead Co-ordination Network (LCN)
was established to assist the JNCC carry out these special
functions. Current or recent projects include:
- the development of guidance on common standards for monitoring
freshwater habitats and species on SSSIs and SACs;
- assisting the technical implementation of the WFD at a UK and
European level;
- developing databases for rivers and lakes to assist in
ecological classification and conservation evaluation;
- creating and testing new systems for classifying freshwater
habitats;
- encouraging the application of conservation evaluation tools
such as SERCON (System for Evaluating Rivers for
Conservation).
Resources
Forests and water guidelines.
Forestry Commission (2000)
Forestry Commission, Edinburgh
Vegetation communities of British rivers – a
revised classification.
Holmes, NT, Boon, PJ & Rowell, TA (1999)
Joint Nature Conservation Committee, Peterborough
A botanical classification of standing waters in
Britain: applications for conservation and
monitoring.
Palmer, MA, Bell, SL, & Butterfield, I (1992)
Aquatic Conservation: Marine and Freshwater Ecosystems,
2, 125-143