Hl. Masse, LONG-TERM EFFECTS OF SHORE ARRANGEMENTS ON FINE-SAND MACROFAUNA AT 2 STATIONS OF PRADOS BAY (NORTH-WESTERN MEDITERRANEAN SEA - GULF OF MARSEILLES), Vie et milieu, 48(2), 1998, pp. 79-87
Since 30 years, the macrofauna of subtidal fine sands has been affecte
d by important shore arrangements, in the Prado bay (Marseille gulf, N
orth-Western Mediterranean Sea). The perturbation is firstly related t
o pier constructions and land reclaiming, and secondly to diversion of
both sewage and freshwater effluents out of the bay. A comparison of
quantitative sampling performed over a 30 year period, at 2-stations,
showed that biodiversity was maintained even improved during that peri
od, but that density and biomass were severely depressed. It is sugges
ted that the improvement in the water quality of the bay has a positiv
e effect on biodiversity, but that the drastic reduction of freshwater
inputs has a negative effect on density and biomass levels of the mac
robenthos. This last point leads to an increase in macrofauna instabil
ity especially for bivalve populations.