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San Francisco Bay - use of dredged material
Attempts to regenerate saltmarsh using dredged material here are valuable because
the marshes are more comparable with saltmarshes in the UK, especially those
on the south coast. Where dredged material is pumped onto low level marsh networks
of creek channels developed. By contrast, where material was placed on upper
marsh levels creek channels did not develop (Atkinson
et al. 2001). This lack of structure is thought to be partly due to the
dewatering process which forms a hard surface layer preventing tidal flows from
forcing creek development. This lack of structure makes the restored marshes
at high levels geomorphologically inferior to marshes, which are allowed to
develop from low-lying sediments (relative to the tidal range).
| Guidance: The San Francisco Bay-Delta watershed efforts are promising,
but they are only considered to be a start. Work is needed in many areas
to increase the amount and effectiveness of restoration activities. More
information on the San Francisco Bay Area Wetlands Ecosystem Goals project
can be viewed and/or downloaded from the San Francisco Estuary Institute
web site at: http://www.sfei.org/
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References
Atkinson, P.W., Crooks, S., Grant, A. & Rehfisch, M.M.
2001.
The Success of Creation and Restoration Schemes in Producing Intertidal Habitat for Waterbirds.
English Nature Research Report, 425
English Nature.
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