Quantifying vegetation and nexton response to tidal restoration of a New England salt marsh

  • Published source details Roman C.T., Raposa K.B., Adamowicz S.C., James-Pirri M. & Catena J.G. (2002) Quantifying vegetation and nexton response to tidal restoration of a New England salt marsh. Restoration Ecology, 10, 450-460


This study is summarised as evidence for the following.

Action Category

Facilitate tidal exchange to restore degraded brackish/salt marshes

Action Link
Marsh and Swamp Conservation
  1. Facilitate tidal exchange to restore degraded brackish/salt marshes

    A before-and-after, site comparison study in 1996–2000 of two brackish/salt marshes in an estuary in Rhode Island, USA (Roman et al. 2002) found that after installing culverts to improve tidal exchange to a degraded marsh, its vegetation became more like a natural marsh. Over two growing seasons following intervention, the overall plant community composition in the tidally restored marsh became more like that in an adjacent natural marsh. Cover of salt marsh plant taxa such as cordgrasses Spartina spp. and glasswort Salicornia europaea increased, whilst cover of common reed Phragmites australis and narrowleaf cattail Typha angustifolia decreased (data reported as cover categories; statistical significance not assessed). After two growing seasons, the overall plant community in the tidally restored marsh remained significantly different from the natural marsh – but was also significantly different from the composition before intervention (data not reported). In the tidally restored marsh, common reed was significantly shorter over three growing seasons following intervention (84–107 cm) than it had been before intervention (136 cm). Methods: The study involved two brackish/salt marshes either side of a road causeway and narrow culvert. In March 1998, full tidal exchange was restored to the degraded, reed-dominated marsh above the road by installing two wider culverts. The marsh below the road remained relatively undisturbed, with full tidal exchange and dominated by salt marsh vegetation. Tidal creeks and pools were excavated in both marshes. Plant species and their cover were surveyed in late summer before (1996) and after (1998, 1999) intervention. Surveys involved 22–28 quadrats/marsh/year, each 1 m2, placed along transects. Common reed stems were also measured in the degraded/restored marsh until late summer 2000.

    (Summarised by: Nigel Taylor)

Output references

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