Contract no. CSA 2462.
|Statement||K. Pye and P.W. French. Vol.5, Management of saltmarshes in the context of flood defence and coastal protection : final report to Ministry of Agriculture, Fisheries and Food, London.|
|Series||Report / Cambridge EnvironmentalResearch Consultants -- no.ES23, Report (Cambridge Environmental Research Consultants) -- ES23.|
|Contributions||French, P. W., Great Britain. Ministry of Agriculture, Fisheries and Food., Cambridge Environmental Research Consultants.|
1. Saltmarshes in south‐east England have been eroding rapidly since Recently, Hughes & Paramor () and Morris et al. () have presented contrasting views on the extent to which physical and biological processes might contribute to the are three contentious issues: (i) saltmarsh erosion is the result of coastal squeeze, where sea walls prevent a landward migration Cited by: Erosion and accretion processes on British saltmarshes Volume 3 - national survey of accretion and erosion status By K. Pye, P French, Cambridge Environmental Research Consultants Ltd. (United Kingdom) and London (United Kingdom) Fisheries and Food Ministry of Agriculture. The vegetation of mangrove swamps and saltmarshes act to reduce wave action and the speed of tidal currents, thus promoting deposition of fine material. Vertical accretion in both environments ranges from a few millimetres a year to several centimetres and includes both organic material and mineral by: van Eerdt MM () The influence of vegetation on erosion and accretion in salt marshes of the Oosterschelde, The Netherlands. Vegetatio 59/– CrossRef Google Scholar Widdows J, Brinsley M, Elliot M () Use of an in situ flume to quantify particle flux (biodeposition rates and sediment erosion) for an intertidal mudflat in.
Saltmarshes are areas of vegetation subject to tidal inundation and are important to birds for several reasons. Saltmarshes are areas of high primary productivity and their greatest significance for coastal birds is probably as the base of estuarine food webs, because saltmarshes export considerable amounts of organic carbon to adjacent habitats, particularly to the invertebrates of mudflats. Yunfeng Zhang, Zhenke Zhang, Huachun He, Yingying Chen, Songliu Jiang, Hang Ren, Processes of small-scale tidal flat accretion and salt marsh changes on the plain coast of Jiangsu Province, China, Acta Oceanologica Sinica, /s, 36, 4, (), (). Next to the management of the sediment supply, improving the long-term saltmarsh stability requires a reduction in sediment dynamics, defined as the temporal changes in the bed level due to erosion or accretion processes (Bouma et al., a; Bouma et al., ). This can be achieved by either reducing the external forcing of the saltmarsh site. This needs more detailed time‐series of erosion and accretion processes and hydrodynamic data during VSWS. Thus, it also requires an instrument with a shorter standoff that can be submerged within shallow water, providing higher‐resolution (both temporal and spatial) bed‐level measurements to adequately characterize the complex.
The above studies imply that erosion and accretion rates are different processes, affecting different parts of the saltmarsh. Accretion rates may be sufficient to raise the saltmarsh surface in response to sea level rise, but at the same time lateral erosion of the seaward edge of saltmarshes may lead to a net reduction of saltmarsh area. In many countries, saltmarshes represent a diminishing resource that threatens both natural changes and human activities. Suggestions that the rate of sea-level rise may accelerate, combined with a possible increase in mid-latitude storms, have raised concerns that the rate of saltmarsh loss may also accelerate, and that existing sea defences may be placed under even greater pressure. The rapid rate of headward erosion suggests that the marsh platform is in disequilibrium and unable to keep pace with high local relative sea level rise (RSLR >mm/yr) through accretionary processes. Biological feedbacks play a strong role in the morphological development of the creeks. Saltmarshes are naturally dynamic systems; many show cycles of erosion and accretion within a given period that may span decades or centuries. In the Severn Estuary there are marsh terraces which reflect periods of erosion or accretion which were governed by changes in the wind-wave climate (Boorman, ).