Geoscience Reference
In-Depth Information
CHAPTER 3
The Rivers and Streams of England and
Wales: An Overview of their Physical
Character in 2007-2008 and Changes
Since 1995-1996
Katharine Seager
1
, Lucy Baker
1
, Helena Parsons
1
, Paul J. Raven
2
and Ian P. Vaughan
3
1
Environment Agency, Warrington, UK
2
Environment Agency, Bristol, UK
3
Cardiff School of Biosciences, Cardiff University, UK
Introduction
2005). Some have been used to report on the
physical state of rivers in various countries (e.g.
Schneiders
et al
., 1993; Raven
et al
., 1998b; Federal
Environment Agency, 2005). River Habitat Survey
(RHS) was developed and used for the first national
assessment of river habitats in the UK (Raven
et al
.,
1997, 1998b). This provided a baseline to establish
future changes and trends in habitat character and
channel modification. A second national survey
was carried out in England and Wales during
2007-2008. This chapter describes the sampling
strategy, key results, changes between the two
surveys and some practical uses of this information
for river management. Further details are
available from http://www.environment-agency.
gov.uk/research/library/publications/123383.aspx.
Assessing the physical character of rivers and
understanding the pressures affecting in-channel
and riparian habitats are extremely important for
river conservation and management (Maddock,
1999; Boon
et al
., 1992; Boon, 2000; Brierley and
Fryirs, 2005; Chessman
et al
., 2006; Erba
et al
.,
2006). For example, this knowledge is essential in
helping to maintain 'high ecological status', achieve
'good ecological status' and prevent the ecological
deterioration of rivers as required by the European
Water Framework Directive (WFD; Council of the
European Communities, 2000; Weiß
et al
., 2008).
Several methods for characterizing and assessing
the physical structure of rivers and riparian
corridors have been developed since the 1990s
(e.g. Schneiders
et al
., 1993; Kondolf, 1995;
Demortier and Goetghebeur, 1996; Raven
et al
.,
1997; Brierley and Fryirs 2000; LAWA, 2000;
Muhar
et al
., 2000; Tickner
et al
., 2000; Braioni
et al
., 2001; Munn e
et al
., 2003; Schneider
et al
.,
2003; Parsons
et al
., 2004; Oliveira and Cortes,
Methods
River Habitat Survey
River Habitat Survey provides a simple, practical
way of characterizing the physical
structure of
