Seed-bank and vegetation development in a created tidal freshwater wetland on the Delaware River, Trenton, New Jersey, USA

  • Published source details Leck M.A. (2003) Seed-bank and vegetation development in a created tidal freshwater wetland on the Delaware River, Trenton, New Jersey, USA. Wetlands, 23, 310-343.


This study is summarised as evidence for the following.

Action Category

Restore/create freshwater marshes or swamps (multiple actions)

Action Link
Marsh and Swamp Conservation
  1. Restore/create freshwater marshes or swamps (multiple actions)

    A study in 1993–1998 of a created, tidal, freshwater marsh in New Jersey, USA (Leck 2003) reported that vegetation was present on the site, but that species richness and cover were highly variable across space and time. Over all samples taken 2–5 years after wetland creation began, 92 plant species were recorded in the marsh. This included 59 wetland-characteristic species, and 14 of 14 planted species. The number of species per sampling quadrat (5–30 species/0.25 m2) and cover of individual plant species (see original paper for full data) were highly variable: depending on the area of the marsh, water level, and year. For example, two years after wetland creation began, jewelweed Impatiens capensis cover was 0–4% in all areas and water levels. After five years, jewelweed cover was 23–58% at the driest points but 0–2% at the wettest points. Methods: In 1993, an area of deposited dredge spoil was cleared of vegetation, excavated to form islands and channels, and graded. Throughout 1994, dams were removed to open the channels. In 1994 and 1995, fourteen herb species were planted across the site. Each August between 1995 and 1998, plant species and their cover were surveyed in 108 quadrats in wetland areas (water depth at high tide approximately 5–50 cm).

    (Summarised by: Nigel Taylor)

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