Marine debris impacts to a tidal fringing-marsh in North Carolina
Published source details
Uhrin A.V. & Schellinger J. (2011) Marine debris impacts to a tidal fringing-marsh in North Carolina. Marine Pollution Bulletin, 62, 2605-2610
Published source details Uhrin A.V. & Schellinger J. (2011) Marine debris impacts to a tidal fringing-marsh in North Carolina. Marine Pollution Bulletin, 62, 2605-2610
This study is summarised as evidence for the following.
Remove debris from brackish/salt marshesAction Link
Remove debris from brackish/salt marshes
A replicated, before-and-after, site comparison study in 2008–2009 in a coastal salt marsh in North Carolina, USA (Uhrin & Schellinger 2011) found that following removal of crab pots and tyres from the marsh, smooth cordgrass Spartina alterniflora height and density typically recovered to undisturbed levels within a year. Immediately before intervention, impacted patches contained fewer cordgrass stems (120–133 stems/m2) than undisturbed marsh (300–370 stems/m2). There was a similar trend (not statistically significant) for the maximum height of cordgrass (impacted: 34–62 cm; undisturbed: 72–80 cm). Patches cleared of crab pots consistently had similar cordgrass height to undisturbed marsh from 22 weeks after clearance (cleared: 25–81 cm; undisturbed: 30–87 cm) and statistically similar cordgrass density to undisturbed marsh from 42 weeks (cleared: 167–229 stems/m2; undisturbed: 302–414 stems/m2). Patches cleared of tyres consistently had similar cordgrass height to undisturbed marsh from 45 weeks (cleared: 50–85 cm; undisturbed: 53–87 cm). However, cordgrass densities remained significantly lower in cleared than undisturbed marsh over the whole study year (33 of 35 comparisons; cleared: 84–273 stems/m2; undisturbed: 287–538 stems/m2). Methods: In August or September 2008, seven wire crab pots and seven vehicle tyres were removed from a salt marsh. Vegetation was surveyed under the debris before removal, then regularly after removal until September 2009. In each survey, live cordgrass stems were counted and measured in 1–2 quadrats covering the footprint of each pot or tyre (including stems growing through the centre of tyres) and seven quadrats in undisturbed patches of the marsh.
(Summarised by: Nigel Taylor)