Geoscience Reference
In-Depth Information
CHAPTER 31
Current and Future Challenges in
Managing Natural System Variability
for River Conservation in European
River Basins
Andrew R.G. Large
School of Geography, Politics and Sociology, Newcastle University, UK
Introduction
this change is estimated to affect 48% of rivers,
59% of lakes, 89% of estuaries and 78% of coastal
waters in England and Wales (WRc, 2006). Current
definitions of morphological pressure are largely
based on the concept of 'damage', principally to
channel morphology but they may also include
impairment of water quality.
The last 20-30 years have been dominated
by conceptual models of how rivers behave
(Figure 31.1); however, predictive assessments that
integrate hydrology, hydraulics, geomorphology
and ecology (and also the complex interplay
between these four variables) are still lacking
(Boon
et al
., 2010; Rice
et al
., 2010; Vaughan
and Ormerod, 2010). In 1992, The International
Conference on Water and the Environment set
out the 'Dublin Principles' which emphasized
that integrated management of rivers and their
basins provides an ideal opportunity to protect
aquatic ecosystems in a truly sustainable manner
(ICWE, 1992). Eighteen years later, the four
Dublin Principles are far from being achieved. For
example, good water resource development and
management should be based on a participatory
approach, involving users, planners and policy-
makers, but this is not being widely practised.
Rivers are immensely important - geologically,
biologically, historically and culturally. They are
central to many of the environmental issues that
concern society, but, a decade into the 21st
century, truly sustainable river conservation and
management actions have not been achieved.
This chapter examines the ways in which the
natural variability of rivers is addressed and
how challenges for river management in the
future are being identified and met. Fluvial
geomorphology is now becoming much more
centrally involved as a discipline underpinning
sustainable river basin management in the United
Kingdom (Newson and Large, 2006) primarily
by helping to define 'reference conditions' (
sensu
Water Framework Directive (WFD), Council of the
European Communities, 2000) that are considered
characteristic of a 'natural', largely undisturbed,
river. A major problem in applying 'natural' and
'reference conditions' and departure from this state
to the rivers of England and Wales is the extent
of historical morphological modification to physical
habitat (Raven
et al
., 1998a; Seager
et al
., this
volume). Morphological pressure resulting from
