Study

Physical evolution of restored breached levee salt marshes in the San Fransico Bay estuary

  • Published source details Williams P.B. & Orr M.K. (2002) Physical evolution of restored breached levee salt marshes in the San Fransico Bay estuary. Restoration Ecology, 10, 527-542

Actions

This study is summarised as evidence for the following.

Action Category

Facilitate tidal exchange to restore/create brackish/salt marshes from other land uses

Action Link
Marsh and Swamp Conservation

Facilitate tidal exchange to restore/create brackish/salt marshes from other land uses

Action Link
Marsh and Swamp Conservation
  1. Facilitate tidal exchange to restore/create brackish/salt marshes from other land uses

    A replicated study in 1979–2000 of six coastal sites where tidal exchange was restored in California, USA (Williams & Orr 2002) reported that three of the sites developed ≥50% vegetation coverage within 15 years. These sites were 0.3–0.9 m above mean sea level when tidal exchange was restored. The other three sites had <50% vegetation coverage after 6–20 years (their maximum age during the study). These sites were 0.5–4.6 m below mean sea level when tidal exchange was restored. Methods: Between 1979 and 1995, levees were deliberately breached to restore tidal exchange in six coastal sites (farmland, mudflats, salt ponds or borrow pits). The area of each site covered by vegetation stands was estimated from historical aerial photographs and field surveys.

    (Summarised by: Nigel Taylor)

  2. Facilitate tidal exchange to restore/create brackish/salt marshes from other land uses

    A replicated study in 1972–2000 of four filled and tidally restored coastal sites in California, USA (Williams & Orr 2002) reported that they developed 50% vegetation coverage within approximately 5–14 years. Any coverage beyond 50% was not quantified. Methods: Between 1972 and 1976, four coastal sites (historical land use not clear) were filled with dredged materials to restore suitable elevations for salt marsh plants (0.5–1.5 m above mean sea level). Then, tidal influx was restored by breaching levees. Note that this study evaluates the combined effect of these interventions. The area of each site covered by vegetation stands was estimated from historical aerial photographs.

    (Summarised by: Nigel Taylor)

Output references

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