Geoscience Reference
In-Depth Information
from pollution, influenced by socio-economic,
technological and biological factors. Improvements
in chemical condition during the later part of the
20th century paved the way for the subsequent
recovery of invertebrate communities. There have
also been considerable improvements in fish
populations - coarse fish now thrive in all parts
of the main stem and migrating salmon are now
being recorded in various reaches and tributaries
(Cowx and O'Grady, 1995). The fishless reaches of
the 1950s and 1960s no longer exist (Langford
et al.,
2010).
Historical studies of ecological and socio-
economic conditions clearly show how far human
activities have shaped river environments and
landscapes. They can contribute important
knowledge to help provide an economic,
sociological and technical framework for future
river conservation and restoration programmes
(Haslam, 1991; Hayashida, 2005). In addition to
a better understanding of the links between the
chemical and ecological attributes of rivers, long-
term records also provide important evidence of
how other factors can affect rivers. These include
rapid economic expansion (industrialization
and population growth), recession (industrial
decline and relocation overseas), war (armaments
manufacture; financial priorities to provide
armaments and defences rather than to protect
the environment; destruction of infrastructure),
and the response to large-scale natural disasters
such as floods, through action to help survival and
reduce risk. It is still unclear to what extent the
recovery of severely polluted rivers such as the
Trent has resulted from purposeful actions (e.g.
enforcement of pollution legislation, technological
progress) compared with the consequences of
economic factors such as recession and industrial
emigration. In this context, the cost of over-
zealous environmental regulation may itself lead
to relocation of industry overseas and thereby
exacerbate recessionary effects. This happened in
the UK during the 1960s (Langford
et al.
, 2010).
Knowledge of historical changes to the
environment can reveal active and passive factors
that have influenced ecological improvement
and this can provide useful insight for meeting
future challenges (MacKenzie
et al.,
2002; Reid
and Ogden, 2006). Further planned analyses
should provide the basis for discriminating
between the effects of active interaction and the
biological responses such as recolonization. This
ability would provide a better basis for investing
resources in the most effective and efficient ways
to achieve and maintain the ecological recovery of
rivers.
Historical analyses can also provide information
to help protect high quality rivers and to
accelerate the recovery of polluted rivers in
developing countries. In many of these regions
recent economic development has produced similar
problems to those of Britain and other developed
countries in the early to mid 20th century, and
environmental concerns are now growing. Our
continuing programme of studies includes analyses
of the socio-economic and historical aspects of
the various industries within the whole Trent
catchment and an assessment of the causes of
varying rates of invertebrate recolonization within
the river system.
Acknowledgements
The authors wish to thank the Environment
Agency for permission to use data from
unpublished records and Mr Alan Roe for
contributions to chemical information and figures.
Staff of Customer Services and Regional Technical
Staff provided data from Environment Agency
records and a special thanks to Charlotte Damary-
Homan for sorting and sending species data. Also
thanks to Miss Karen Robson and staff of the
University of Southampton Archives and Special
Collections who have analysed and listed the
historic data records and helped us with access to
the data at all times. Mrs Jean Langford compiled
and corrected the bibliography and copy edited the
text for which we are very grateful. Most of the
archived data originated from Mr Frank Woodiwiss
who began regular biological surveys in the
Trent catchment and to whom freshwater science
is deeply indebted for his foresight. Thanks to
Professor Phil Boon who organized the conference
and to the referees who gave valuable guidance on
the final submission.
