The composition and distribution of the macrobenthic community in a lagoon in the Po River delta were investigated by taking monthly samples at 3 sites during 1994. A total of 38 macroinvertebrate taxa, representing 5 phyla, were identified. Gastropods, amphipods, and chironomid larvae dominated the macrofauna in term of abundance, while in terms of biomass bivalves were the dominant taxon. Monthly total invertebrate abundance showed considerable fluctuation, depending on the season and on the presence of the red macroalgae Gracilaria verrucosa. In the central area of the lagoon, a significant relationship was demonstrated between macrobenthic community parameters and amount of macroalgal cover. Taking the most important species, i.e. those that mostly contributed to similarity within sites, only Cerastoderma glaucum was found negatively related to the amount of macroalgal biomass. Mean annual secondary production varied between 50 and 75 g AFDW m-2 yr-1 depending on the site, yielding P/B ratios between 1.02 and 1.08. Confinement and moderate disturbance due to the presence of algal cover are hypothesized to determine structure, composition, and production of the macrobenthic community in the Sacca di Goro
Structure and secondary production of a soft bottom macrobenthic community in a brackish lagoon (Sacca di Goro, north-eastern Italy)
MISTRI, Michele;ROSSI, Remigio;FANO, Elisa Anna
2001
Abstract
The composition and distribution of the macrobenthic community in a lagoon in the Po River delta were investigated by taking monthly samples at 3 sites during 1994. A total of 38 macroinvertebrate taxa, representing 5 phyla, were identified. Gastropods, amphipods, and chironomid larvae dominated the macrofauna in term of abundance, while in terms of biomass bivalves were the dominant taxon. Monthly total invertebrate abundance showed considerable fluctuation, depending on the season and on the presence of the red macroalgae Gracilaria verrucosa. In the central area of the lagoon, a significant relationship was demonstrated between macrobenthic community parameters and amount of macroalgal cover. Taking the most important species, i.e. those that mostly contributed to similarity within sites, only Cerastoderma glaucum was found negatively related to the amount of macroalgal biomass. Mean annual secondary production varied between 50 and 75 g AFDW m-2 yr-1 depending on the site, yielding P/B ratios between 1.02 and 1.08. Confinement and moderate disturbance due to the presence of algal cover are hypothesized to determine structure, composition, and production of the macrobenthic community in the Sacca di GoroI documenti in SFERA sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
