Effects of an intertidal sediment fence on sediment elevation and vegetation distribution in a Venice (Italy) lagoon salt marsh

On a intertidal flat in the lagoon of Venice (Italy), the effects of a fenc e on sediment elevation and vegetation establishment were studied throughou t the years 1994-1997. With the use of a sedimentation erosion table (SET) we measured 5.7 cm of accumulated sediment in the protected tidal flat afte r 28 months (2.5 cm/year), compared with - 0.7 cm (- 0.3 cm/year) in a near by, unprotected tidal flat. After a storm which damaged part of the fence, there was a similar loss in elevation in both tidal flats; following repair , only the protected tidal flat gained elevation. After 1 and 3 years, vege tation coverage (mainly due to Salicornia veneta, Sarcocornia fruticosa and Atriplex portulacoides) was higher along the edge of the salt marsh of the protected tidal flat compared to the control salt marsh, but differences w ere not significant. (C) 2000 Elsevier Science B.V. All rights reserved.