Seasonal response of benthic foraminifera to anthropogenic pressure in two stations of the Gulf of Trieste (northern Adriatic Sea, Italy): the marine protected area of Miramare versus the Servola water sewage outfall

Abstract

A seasonal survey of living benthic foraminifera was performed in 2013 in the Gulf of Trieste (N Adriatic Sea) to compare two marine coastal sites with different degrees of anthropogenic influence. An assessment of ecological quality statuses showed that the station located near the end of an urban pipeline (Ser station), has worse ecological conditions than the site located in a protected marine area (Res station) all year around. Stressed conditions at Ser station were mainly related to high contents of total organic carbon (TOC) and Zn in the bioavailable fraction, which were a limiting factor for the studied foraminiferal communities. Ammonia tepida, Bolivina spp., and Bulimina spp., which characterised this station, were the most tolerant taxa of the studied assemblage. Conversely, Elphidium spp., H. depressula, N. iridea, Quiqueloculina spp., R. nana and Textularia spp., could be considered less tolerant species as they benefitted from the less stressful conditions recorded at Res station, despite slightly higher concentrations of some potentially toxic elements (PTEs), especially Pb, being recorded in this station in comparison to Ser station. Furthermore, foraminiferal assemblages were found to be quite resilient over an annual cycle, being able to recover from a seasonal unbalanced state to a mature one. The beginning of spring and latest summer would be the best period to assess the ecological quality status to avoid any under- or overestimation of the health of the environment.

Foraminiferal-based biotic indices to assess the ecological quality status of the Gulf of Gabes (Tunisia): Present limitations and future perspectives

“…This index "forecasts" the number of species in a given sample that would be present if each were equally common (e.g., similar H′ bc ). This diversity index was applied to assess the EcoQS in the Norwegian Skagerrak coast (Bouchet et al, 2012), along the Italian coasts (Bouchet et al, 2018;Melis et al, 2019) and to reconstruct the paleoEcoQS in the eastern English Channel (Francescangeli et al, 2016). 2The Tolerant Species index (% TS std ) developed by Barras et al (2014) is based on the relative proportion of stress-tolerant taxa as a function of the grain size (< 63 μm).…”

Opportunities and challenges in incorporating benthic foraminifera in marine and coastal environmental biomonitoring of soft sediments: from science to regulation and practice

“…In Norwegian fjords, it has been shown that benthic foraminiferal communities significantly correlate with benthic macrofaunal communities, confirming that foraminifera can be as good sentinels of environmental conditions as macrofaunal (Bouchet et al, 2018a). Furthermore, foraminiferal indices based on diversity (Alve et al, 2009; and on the sensitivity of species to organic pollution (Barras et al, 2014;Dimiza et al, 2016;Alve et al, 2016; have been designed, and successfully applied to assess ecological quality statuses Dolven et al, 2013;Barras et al, 2014;Francescangeli et al, 2016;Dijkstra et al, 2017;Bouchet et al, 2018b;Jesus et al, 2018;Alve et al, 2019;Melis et al, 2019). Alve et al (2019) also demonstrated that foraminifera and macrofauna have similar indicator efficiency by applying a foraminiferal multimetric index (NQIf) as an alternative, which is an adaptation of the Norwegian Quality Index (NQI), an internationally intercalibrated macrofauna index.…”

Effects of pollution on marine organisms

“…Living foraminifera species were used as ecological indicators in the southwestern Atlantic Ocean and the Adriatic Sea. The proximity of coral reefs to wastewater‐impacted river discharge from the Buranhém River, Brazil, was found to be associated with lower density of foraminifera ( Amphistegina gibbosa ) populations and higher frequency of bleaching (Marques et al, 2019), while differences in total density, species richness, dominance, and ecological quality indices were observed between a wastewater‐impacted site and a marine reserve location in the Gulf of Trieste (Adriatic Sea) (Melis et al, 2019).…”