40
Cooper, N.J. et al.
Bakker, J. P., Esselink, P., van der Wal, R. & Dijkema, K. S.
1997. Restoration and management of coastal salt marshes.
In: Urbanska, K.M., Webb, N.R. & Edwards, P.J. (eds.)
Restoration ecology and sustainable development, Cam-
bridge University Press, Cambridge.
Burd, F. 1992. Erosion and vegetation change on the salt
marshes of Essex and north Kent between 1973 and 1988.
Nature Conservancy Council, Research and survey in
nature conservation, Report No 42.
Cooper, N.J., Skrzypczak, T. & Burd, F. 2000. Erosion of the
salt marshes of Essex between 1988 and 1998. Vol. 1:
Implications for flood defence and nature conservation;
Vol. 2: A recommended monitoring framework for the
future; Vol. 3: Maps of changes in the Essex salt marshes,
1988-1998. Report to Environment Agency (Anglian Re-
gion).
Frey, R.W. & Bason, P.B. 1978. North American salt marshes.
In: Davis, R. AA. (ed.) Coastal sedimentary environ-
ments, pp. 104-164. Springer, Berlin.
marsh has been lost from Essex. This net loss has been
due to both reclamation for port developments and
erosion. Potential hypotheses for this large-scale ero-
sion have been identified as follows:
• Inhibition of the long-term estuarine ‘roll-over’ in
response to sea level rise and resulting coastal ‘squeeze’
between rising sea level and existing flood defences;
• Long-term morphological response to land reclama-
tion, resulting in reduced protection offered by natural
features;
• Internal dissection of existing marshes;
• Cyclic behaviour of coastal systems;
• Changing forcing conditions;
• Self-regulating nature of geomorphological systems.
The implications of the observed losses have been
discussed in both nature conservation and coastal de-
fence terms. It is suggested that the current management
practice of ‘hold the existing line of structural defences’
(as identified as the preferred shoreline management
policy for the next 10 yr throughout many parts of
Essex) is not sustainable in the longer term, and contin-
ued salt marsh loss will occur as long as this policy is
implemented. This will ultimately result in increasing
damage to existing engineered defences, increasing loss
of internationally important habitats, and increasing pres-
sure on relevant authorities under the EC Habitats Di-
rective and UK Conservation Regulations to ensure that
the integrity of the internationally designated conserva-
tion sites is maintained or enhanced.
Greensmith, J.T. & Tucker, E.V. 1966. Morphology and evo-
lution of inshore shell ridges and mud-mounds on modern
inter-tidal flats, near Bradwell, Essex. Proc. Geol. Ass.
77(3): 329-346.
Leggett, D.J. & Dixon, M. 1994. Management of the Essex
salt marshes for flood defence. In: Falconer, R. & Good-
win, P. (eds.) Wetland management. I.C.E, London.
Lowe, J.P. 1999. Geomorphological investigations for the
rivers Crouch and Roach. Report to the Environment
Agency (Anglian Region), Report No: STCG15.
Möller, I. Spencer, T. & French, J.R. 1996. Wind wave attenu-
ation over salt marsh surfaces: preliminary results from
Norfolk, England. J. Coastal Res. 12: 1009-1016.
Pethick, J.S. 1996. Geomorphological trends in the Blackwa-
ter estuary, 1978 to 1994. Report to NRA and English
Nature.
Pethick, J.S. 1998. Tollesbury managed set-back: Sedimen-
tary processes. Report to Environment Agency Salt Marsh
Steering Group.
Pethick, J.S. 1999. Environment Agency Estuaries Training
Course. Presented to Environment Agency (South West
Region).
Acknowledgements. The authors would like to thank the
Environment Agency (Anglian Region) for their provision of
the aerial photography used during the study, and their permis-
sion to publish results from the study which was funded under
contract number STCG/1998/28. Figs. 2 and 3 courtesy of
Environment Agency. The views expressed in this paper are
entirely those of the authors and not necessarily those of the
Environment Agency.
Pethick, J.S. 2001. Coastal management and sea-level rise.
Catena 42: 307-322.
Pethick, J.S. in press. The Anglian Coast. In: von Bodungen,
B. & Turner, K. (eds.) Science and integrated coastal
management. Dahlem University Press.
References
Anon. 1974. Aspects of the ecology of the coastal area in the
outer Thames estuary and the impacts of the proposed
Maplin airport. DoE research contract DGR 205/2, Insti-
tute of Terrestrial Ecology.
Ranwell, D.S. 1972. Ecology of salt marshes and sand dunes.
Chapman and Hall, London.
Anon. 1994. A guide to the understanding and management of
salt marshes. R&D Note 324, NRA - National Rivers
Authority.
Anon. 1997. Essex shoreline management plan. April 1997.
Mouchel and Partners Ltd., Surrey.
Received 17 May 2000;
Revision received 22 March 2001;
Accepted 22 March 2001.
Coordinating Editor: W. Ritchie.
Anon. 1999. Environment agency estuaries training course.
Course literature prepared for Environment Agency (South
West Region), June 1999, CGP – Coastal Geomorphology
Partnership.