The meiofaunal abundance, biomass, community structure and nematode diversity were investigated in relation to the spatial distribution of the potential food sources in the Atacama trench and open slope (South Pacific Ocean).

The majority of Hydrozoa is represented by not readily noticeable, small species. In recent decades, however, taxonomic knowledge of the group has increased worldwide, with a significant number of investigations focused on the Mediterranean Sea. Over more than two decades, 115 species of hydrozoans were recorded from coastal waters along nearly 300 km of the Salento Peninsula (Apulia, Italy). For each species, records from different collections were merged into single sheets of a general database.

The hypothesis that, temporal variation in nematode abundance, community composition and trophic structure is coupled with changes in the quantity and quality of their potential food sources was tested.

The direct or indirect influence of a river plume on meiofaunal abundance and community composition was investigated in the North Adriatic Sea (NW Mediterranean Sea).