Benthic Foraminifera in the Lagoon and Gulf of Venice: a Proxy to Monitor Coastal Environments

The recent benthic foraminiferal distribution in the Lagoon and Gulf of Venice has been described through the quantitative analysis of about 1000 bottom samples collected in the '80s and '90s. The benthic foraminiferal assemblage shows a high level of uniformity and stability within areas characterised by similar physical and chemical parameters (biotopes). The foraminiferal biotopes have a response time to environmental changes of the order of a few years, so the temporal comparison between biotopes before and after anthropic interventions is particularly useful for applicative approaches. To assess the degree of recent environmental change, the quantitative data have been used for a comparison using the Kolmogorov-Smirnov non-parametric test in two area with great anthropic influence, in the central lagoon and at the Lido Inlet. Between 1980-1990 and 2001 little or no biotope change occurred over more than 50% of the lagoon. On the Lido Inlet a comparison was obtained between samples collected in 1983 and 2006: the high similarity in the foraminiferal assemblages of the two periods strongly suggests that the physical and chemical characteristics, within the sampled area, have not greatly changed during the intervening 23 years. The knowledge of the biotopes distribution gives an overall picture of the characteristics of the Lagoon of Venice and Northern Adriatic Sea for monitoring the effects of the engineering interventions ongoing at the lagoon inlets.