Benthic foraminiferal assemblages and sedimentological characterisation of the coastal system of the Cagliari area (southern Sardinia, Italy)

A survey of the coastal environment of Cagliari Harbour and the surrounding areas (southern Sardinia, Italy) has made it possible to study living benthic foraminiferal assemblages from 15 superficial sediments from the coastal system of the Gulf of Cagliari. This allowed a comparison of the distribution of recent living benthic foraminifera with sedimentological parameters to be done. Foraminiferal density and species’ richness are variable across the study area. The living assemblages are characterised by low diversity in the harbour and in the Santa Gilla Lagoon. In total, 95 different species were recognized, 18 of which being epiphytic, prefer an attached lifestyle, 54 are epifaunal and 23 infaunal. Epifaunal and epiphytic species such as Peneroplis pertusus (Forskal, 1775), Rosalina bradyi (Cushman, 1915) and Lobatula lobatula (Walker & Jacob, 1798) are the main constituents of the living foraminiferal assemblages in the sandy sediment far from the harbour area and are associated with Posidonia oceanica (L.) Delile, 1813 seagrass. The low biodiversity values registered in some samples from this area can be related to the anthropogenic discharge of pollutants and fluctuating environmental parameters. Historical benthic foraminiferal assemblages from Cagliari Harbour, determined by H.B. Brady and published by Wright in 1871, have been reported for their historical value.