04/06/2006

I. Guala, S. Simeone, M.C. Buia, S. Flagella, M. Baroli, G. De Falco

Abstract

The removal of beach-cast Posidonia oceanica seagrass litter, called ‘banquettes’, was analyzed on the
island of Sardinia (western Mediterranean) in order to quantify this practice on a broad scale, to evaluate
the potential impacts on the beach geomorphology and the ecological implications for coastal ecosystems.
‘Banquette’ removal resulted to be a widespread practice applied on  beaches (out of 116), along 11 km
of shoreline out of the 28 km analyzed; in the year 200 the total amount removed was 106,180 m³, mainly
in low energy beaches. Meadow leaf production was assessed in  localities which collectively account for
about 0% of P. oceanica removed from Sardinian beaches; the loss of biomass due to the removal varied
between 1.8 and 1.% of meadow production. The main consequences of leaf material removal are the
loss of sediment and the permanent depletion of biogenic elements from the shore. Management measures
are suggested in order to minimize the possible effects on the dynamics of shoreline and the growth in front
of the meadows.

Biol. Mar. Medit. 13