Study

Canopy architecture of natural and planted cordgrass marshes: selecting habitat evaluation criteria

  • Published source details Zedler J.B. (1993) Canopy architecture of natural and planted cordgrass marshes: selecting habitat evaluation criteria. Ecological Applications, 3, 123-138.

Actions

This study is summarised as evidence for the following.

Action Category

Deposit soil/sediment and introduce vegetation: brackish/salt marshes

Action Link
Marsh and Swamp Conservation

Reprofile/relandscape: brackish/salt marshes

Action Link
Marsh and Swamp Conservation

Directly plant non-woody plants: brackish/saline wetlands

Action Link
Marsh and Swamp Conservation
  1. Deposit soil/sediment and introduce vegetation: brackish/salt marshes

    A site comparison study in 1989 of four estuarine salt marshes in California, USA (Zedler 1993) found that parts of a marsh created by depositing sediment and planting California cordgrass Spartina foliosa supported a similar cordgrass density to adjacent natural marshes, but with shorter plants. Statistical significance was not assessed. After 7–9 years, four of six transects in the created marsh supported a cordgrass density (100–193 stems/m2) within the range of nearby natural marshes (73–193 stems/m2). The other two transects supported a lower cordgrass density (40–60 stems/m2). However, a greater proportion of stems were in shorter height classes in the created marshes than in the natural marshes (data reported graphically). Methods: In September 1989, California cordgrass was surveyed in 0.1-m2 quadrats. Thirty-six quadrats (six transects) were surveyed in a marsh created by depositing dredge spoil (in 1980) then planting California cordgrass (in 1984–1986). Fifty-four quadrats (seven transects) were surveyed in three nearby natural marshes.

    (Summarised by: Nigel Taylor)

  2. Reprofile/relandscape: brackish/salt marshes

    A site comparison study in 1989 of four estuarine salt marshes in California, USA (Zedler 1993) found that a marsh created by reprofiling, planting California cordgrass Spartina foliosa and fertilizing supported a similar cordgrass density to adjacent natural marshes, but with shorter plants. Statistical significance was not assessed. Five years after reprofiling, four of four transects in the created marsh supported a cordgrass density (133–173 stems/m2) within the range of nearby natural marshes (73–193 stems/m2). However, cordgrass was shorter in the created than natural marshes, with a greater proportion of stems in shorter height classes (see original paper for data). Methods: In September 1989, California cordgrass was surveyed in 0.1-m2 quadrats. Twelve quadrats (four transects) were surveyed in a created marsh (reprofiled into islands and creeks in 1984, planted with California cordgrass in 1985, fertilized with urea in 1985–1986; same marsh as in Study 2). This study evaluates the combined effect of these interventions on any non-planted cordgrass. Fifty-four quadrats (seven transects) were surveyed in three nearby natural marshes.

    (Summarised by: Nigel Taylor)

  3. Directly plant non-woody plants: brackish/saline wetlands

    A site comparison study in 1989 of four estuarine salt marshes in California, USA (Zedler 1993) found that a marsh created by reprofiling, planting California cordgrass Spartina foliosa and fertilizing supported a similar cordgrass density to adjacent natural marshes, but with shorter plants. Statistical significance was not assessed. Four years after planting, four of four transects in the created marsh supported a cordgrass density (133–173 stems/m2) within the range of nearby natural marshes (73–193 stems/m2). However, cordgrass was shorter in the created than natural marshes, with a greater proportion of stems in shorter height classes (see original paper for data). Methods: In September 1989, California cordgrass was surveyed in 0.1-m2 quadrats. Twelve quadrats (four transects) were surveyed in a created marsh (reprofiled into islands and creeks in 1984, planted with California cordgrass in 1985, fertilized with urea in 1985–1986; same marsh as in Study 7). This study evaluates the combined effect of these interventions on any non-planted cordgrass. Fifty-four quadrats (seven transects) were surveyed in three nearby natural marshes.

    (Summarised by: Nigel Taylor)

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