*2.3. Meiofaunal Analysis*

The samples were rinsed with a gentle jet of fresh water through a 0.5 mm sieve to separate the macrofauna from the meiofauna [48]. They were then decanted, sieved 10 times through a 42 μm mesh and centrifuged three times with Ludox HS30 (specific density 1.18 g/cm3) [51]. The obtained animals were then transferred to a "Delfuss" Petri dish with a checkered bottom (200 squares, to make counting easier), sorted into their major taxa under a Leica G26 stereomicroscope, and counted.

All the values obtained was recalculated as abundance per 10 cm2. The richness (number of major taxa), Shannon's diversity, Pielou's evenness indices (log2) were calculated to describe the structure of the meiofaunal assemblage. The possible occurrence of anthropogenic impact on the meiofaunal community was also assessed by the total number of nematodes (Ne) and copepods (Co) computed in the Ne:Co ratio. This index was proposed by Ra ffaelli and Mason [52] for the pollution monitoring with meiofauna. The hypothesis was that the divergent auto-ecological characteristics of these two abundant and frequent meiofaunal components (the extreme tolerance of nematodes and the high sensitivity of copepods) might detect the occurrence of human stress in marine sediments.
