190
R.G. Hughes
context of increasing the success of managed realignment schemes and in
reducing erosion of extensive saltmarsh creek systems.
A hypothesis is proposed that in low-lying managed realignment sites
sediment will accumulate initially, but, as the surface of the sediment becomes
elevated, the rate of accretion will decrease and the rate of erosion increase.
The sediment elevation will reach a dynamic equilibrium, the height of which
will be affected by the interaction of physical and biological factors. Invertebrates may colonise the accreted sediment and prevent establishment of
vegetation, indirectly by making the sediment more erodable, and directly by
herbivory and bioturbation. The invertebrates that colonise the sediments of
extensive creek systems may exacerbate erosion that initiates a positive feedback, in which erosion leads to more erosion because of increased tidal flows.
Consequently, it is predicted that further management will be necessary to
promote sediment accretion and ensure successional development of saltmarsh vegetation, in managed realignment sites and in eroding saltmarsh
creeks.
References
Adam P (1990) Saltmarsh ecology. Cambridge Univ Press, Cambridge
Allen JRL, Pye K (1992) Coastal saltmarshes: their nature and importance. In: Allen JRL,
Pye K (eds) Saltmarshes. Morphodynamics, conservation and engineering significance. Cambridge Univ Press, Cambridge, pp 1-18
Austen I, Anderson TJ, Edelvang K (1999) The influence of benthic diatoms and invertebrates on the erodability of an intertidal mudflat, the Danish Wadden Sea. Estuar
Coast Shelf Sci 49:99-111
Beardall CH, Dryden RC, Holzer TJ (1988) The Suffolk Estuaries. The Suffolk Wildlife
Trust, Saxmundham, Suffolk
Boorman L, Goss-Custard JD, McGrorty S (1989) Climatic change, rising sea level and
the British coast. ITE research publication 1. HMSO, London, pp 1-24
Burd F (1992) Erosion and vegetation change on the saltmarshes of Essex and north Kent
between 1973 and 1988. Research and survey in nature conservation, vol 42. Nature
Conservancy Council, Peterborough, 116 pp
Burd F (1995) Managed retreat: a practical guide. English Nature, Peterborough
Cahoon DR, French JR, Spencer T, Reed DJ, Moller I (2000) Vertical accretion versus
elevational adjustment in UK saltmarshes: an evaluation of alternative methodologies. In: Pye K, Allen JRL (eds) Coastal and estuarine environments. Geological
Society special publication. Geological Society, London, 175:223-238
Daborn GR, Amos CL, Berlinsky M, Christian H, Drapeau G, Faas RW, Grant J, Long B,
Paterson DM, Perillo GME, Piccolo MC (1993) An ecological "cascade" effect.
Migratory birds affect stability of intertidal sediments. Limnol Oceanogr 38:225-231
Davey JT (1994) The architecture of the burrow of Nereis diversicolor and its quantification in relation to sediment-water exchange. J Exp Mar BioI EcoI179:115-129
Davey JT, Partridge VA (1998) The macrofaunal communities of the Skeffling muds
(Humber Estuary), with special reference to bioturbation. In: Black KS, Peterson DM,
R.G. Hughes
context of increasing the success of managed realignment schemes and in
reducing erosion of extensive saltmarsh creek systems.
A hypothesis is proposed that in low-lying managed realignment sites
sediment will accumulate initially, but, as the surface of the sediment becomes
elevated, the rate of accretion will decrease and the rate of erosion increase.
The sediment elevation will reach a dynamic equilibrium, the height of which
will be affected by the interaction of physical and biological factors. Invertebrates may colonise the accreted sediment and prevent establishment of
vegetation, indirectly by making the sediment more erodable, and directly by
herbivory and bioturbation. The invertebrates that colonise the sediments of
extensive creek systems may exacerbate erosion that initiates a positive feedback, in which erosion leads to more erosion because of increased tidal flows.
Consequently, it is predicted that further management will be necessary to
promote sediment accretion and ensure successional development of saltmarsh vegetation, in managed realignment sites and in eroding saltmarsh
creeks.
References
Adam P (1990) Saltmarsh ecology. Cambridge Univ Press, Cambridge
Allen JRL, Pye K (1992) Coastal saltmarshes: their nature and importance. In: Allen JRL,
Pye K (eds) Saltmarshes. Morphodynamics, conservation and engineering significance. Cambridge Univ Press, Cambridge, pp 1-18
Austen I, Anderson TJ, Edelvang K (1999) The influence of benthic diatoms and invertebrates on the erodability of an intertidal mudflat, the Danish Wadden Sea. Estuar
Coast Shelf Sci 49:99-111
Beardall CH, Dryden RC, Holzer TJ (1988) The Suffolk Estuaries. The Suffolk Wildlife
Trust, Saxmundham, Suffolk
Boorman L, Goss-Custard JD, McGrorty S (1989) Climatic change, rising sea level and
the British coast. ITE research publication 1. HMSO, London, pp 1-24
Burd F (1992) Erosion and vegetation change on the saltmarshes of Essex and north Kent
between 1973 and 1988. Research and survey in nature conservation, vol 42. Nature
Conservancy Council, Peterborough, 116 pp
Burd F (1995) Managed retreat: a practical guide. English Nature, Peterborough
Cahoon DR, French JR, Spencer T, Reed DJ, Moller I (2000) Vertical accretion versus
elevational adjustment in UK saltmarshes: an evaluation of alternative methodologies. In: Pye K, Allen JRL (eds) Coastal and estuarine environments. Geological
Society special publication. Geological Society, London, 175:223-238
Daborn GR, Amos CL, Berlinsky M, Christian H, Drapeau G, Faas RW, Grant J, Long B,
Paterson DM, Perillo GME, Piccolo MC (1993) An ecological "cascade" effect.
Migratory birds affect stability of intertidal sediments. Limnol Oceanogr 38:225-231
Davey JT (1994) The architecture of the burrow of Nereis diversicolor and its quantification in relation to sediment-water exchange. J Exp Mar BioI EcoI179:115-129
Davey JT, Partridge VA (1998) The macrofaunal communities of the Skeffling muds
(Humber Estuary), with special reference to bioturbation. In: Black KS, Peterson DM,