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Post treatment at Tollesbury
Seeding and planting
Different methods of sowing and planting were tried.
- Seeds mixture of various saltmarsh plants, sown at low density;
- Seeds mixture of carious saltmarsh plants, sown at high density;
- A mixture of saltmarsh plants specifically raised for the purpose of planting
on the site;
- Plugs of saltmarsh vegetation planted on the site;
- A control.
| Guidance: The results of the monitoring indicate that the most
successful treatment in terms of time taken for plant establishment was
the use of plugs of soil and vegetation cut from existing saltmarshes. However,
whatever method is employed vegetation only grew at levels 1.5m above Ordnance
Datum. |
"This raises the possibility that enhancing saltmarsh development by introducing
seed or plants may be appropriate for similar schemes. Poor survival of most
species introduced at Tollesbury, except at the highest elevations, means that
we have limited information on the scope for deliberate introductions. However
plants of sea aster Aster tripolium and saltmarsh
grass Puccinellia maritima were successfully
introduced and, having survived at relatively stable densities for four years,
are now firmly established and expanding in area. Some of the problems encountered
with establishing plants, particularly over agricultural soils, could be avoided
in future sites and, where necessary (i.e. where the costs can be justified
in relation to the outcome) carefully designed planting schemes could augment
and increase the rates of saltmarsh development." (Gray
2002).
Drainage and creek formation
Creek development has begun to take place. There is some indication that the
pattern of emerging creeks is begetting to resemble the network present on the
site before enclosure. The large areas of poorly drained mudflats within the
Tollesbury site also raises the prospect of post-breach engineering, including
provision of a creek system or the use of bunds to reduce wave generation. The
picture in the summary
file provides some indication of this development.
References
Gray, A.J.
2002.
Coastal Realignment - an Overview of Tollesbury.
CHaMPs.
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