COASTAL WETLANDS

 
I. Distribution

     A. Sites

    B. Losses
        conversion to deep water
        urban use
        conversion to non-vegetated types
        transition to freshwater
        agriculture


II. Elements which control vegetation structure and establishment

A. Sediment

B. Salinity

C. Elevation/tides

D. Salinity x elevation

E. Energy

F. Soil

G. Drainage

H. Seed source

I . Spartina invasions

 
III. Restoration approaches

     A. Dike breaching, Salmon River, Oregon (R. Frenkel and J. Morlan 1990. Restoration of the Salmon River marshes: Retrospect and prospect. Final Report to EPA. Department of Geosciences, Oregon State University, Corvallis, 142 p.)
        1.Breaching dikes

        2. Recontouring upland or filled former wetland

        3. Hydrologic modification to induce accretion
 
        4. Recommendations
            Restore complete hydrologic connection
            Connect through dikes at former creek locations
            Survey elevations
            If planting, collect salinity and soil data
            Planting may be optional
            You can contour, but beware
            Post-project monitoring

    B. Connector Marsh, San Diego
        (Josselyn et al in J. Kusler and M. Kentula 1990.
Wetland Creation and Restoration: The Status of the Science. Island Press, Washington, D.C., 591 p.), Langis et al 1991 in Ecological Applications, Zedler 1993 in Ecological Applications, Gibson et al 1994 in Ecological Applications)
        1.  Tidal marsh
        2.
  Spartina foliosa
        3.
  Clapper rail
        4.  Nutrient cycling
        5.
  Organic matter

    C. Gog-le-hi-te Wetland, Tacoma in (Josselyn et al in J. Kusler and M. Kentula 1990. Wetland Creation and Restoration: The Status of the Science. Island Press, Washington, D.C., 591 p.)
        1. Goals
        2.  Judgement of success
        3.
  Unanticipated results

    D. Bracut Marsh mitigation bank, Arcata Bay, CA in (Josselyn et al in J. Kusler and M. Kentula 1990. Wetland Creation and Restoration: The Status of the Science. Island Press, Washington, D.C., 591 p.)
        1.  Restore tidal action to a diked area that had been filled with wood debris, gravel
        2.  Import soil to encourage vegetation growth
        3.
  Remove debris
        4.
  Plant Spartina foliosa
        5.  Problems:
            Plant list used was for another, more southern, area
           Wood debris decay
            Spartina is not growing

    E. Hayward Regional Shoreline, Alameda County, CA in (Josselyn et al in J. Kusler and M. Kentula 1990. Wetland Creation and Restoration: The Status of the Science. Island Press, Washington, D.C., 591 p.)
        1.  To restore tidal action to a former salt crystallizer and recreate emergent marsh
        2.  Specific goals:
            Create area to be colonized by Spartina foliosa
            Excavate channels to retain water and provide shorebird habitat at low tide
            Create nesting islands
        3.  Success:
            Salt concentration in lower soil layers stayed high
            Fish, invertebrates and birds colonized
            Vegetation did not establish

    F. Shorebird Marsh, Marin County, CA in (Josselyn et al in J. Kusler and M. Kentula 1990. Wetland Creation and Restoration: The Status of the Science. Island Press, Washington, D.C., 591 p.)
        1.  Mitigation for regional shopping center
        2. To provide flood control during winter and create tidal saltmarsh during summer
        3.
  Goals:
            Create extensive habitat for, and plant, Spartina foliosa
            Make islands and channels
            Construct pump and structure to pump out water during floods
                and limit maximum tide during growing season
        4.  Success:
            Facility was to be managed for flood control from 15 Oct to 15 Apr, then operated
             as a tidal marsh.  Public works employees did not grasp this the first year.
            Flap gate failed second year; outflow channel silted up.
            Citizens' committee took over management of marsh; experimental plantings failed
                because of lack of tidal action.
            In third year, tidal action was implemented in summer.