Foraminiferal Assemblages of Experimental Banks and Control Sites in the Venice Lagoon, Italy

In order to better understand the ecological impacts of sediment relocation, sediment banks were constructed in the Venice Lagoon, Italy in November 2005. Examination of living (Rose Bengal stained) foraminifera (>150um) collected from push cores taken in May 2007 from the Venice Lagoon, Italy revealed differences in foraminiferal assemblages between constructed banks at site V1 and control sites SS0 (sediment source) and SS1 (site adjacent to the banks). At site V1, banks were constructed using contaminant type A sediments (low contaminant levels) from site SS0. Although total abundances of foraminifera at these sites were similar, the bank site (V1) had substantially higher densities in the upper 1.5 cm compared to those of the SS0 and SS1 cores. All of the cores examined for this study were dominated by Ammonia spp. and Haynesina germanica. However, H. germanica had a density maximum in the 0-1 cm interval, dominating the surface interval of V2, while Ammonia spp. dominated the surface sediments of sites SS0 and SS1, and the infaunal (below 1cm) habitats of all cores. Although these results are based on unreplicated cores, differences in H. germanica densities in the upper 1cm of core V1 compared to undisturbed sediment sites support the idea that this taxon is a pioneer species or a resilient carry-over from the source sediments that is able to thrive in disturbed sediments. This Material is produced in the framework of the SIOSED project, supported by Magistrato alle Acque di Venezia ( Venice Water Authority), throughout Consorzio Venezia Nuova and Thetis S.p.A. Any opinions, findings, and conclusions expressed in this publication are those of the author and do not necessarily reflect the views and opinions of the Magistrato alle Acque di Venezia (Venica Water Authority), Consorzio Venezia Nuova, or Thetis S.p.A.