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We studied the influence of anomalous meteorological and hydrological conditions that occurred in the Gulf of Trieste from March 2006 to February 2007 on phytoplankton structure and function. We computed monthly mean (or median) air temperature, total precipitation, wind speed, river discharge, seawater temperature, salinity, photosynthetic available radiation (PAR), cyanobacteria, nano- and microphytoplankton abundances during the study year and compared them to climatological (1999-2014 for PAR; 1999-2007 for nanophytoplankton; 1998-2015 for the other variables) mean/median data. We then related the cyanobacteria (0.2-2 μm), nano- (2-20 μm) and microphytoplankton (20-200 μm) of the study year to inorganic nutrient concentrations. Median river inputs in October and November were 9- and 15-fold lower, respectively, than the time series medians, with consequent high salinity from May to November (up to +1.26 compared to the climatological data). Monthly mean seawater temperatures were lower than the climatological values (-2.95 °C at the surface) from March to August 2006 and higher (+2.15 °C at the surface) from September to February 2007. Reductions in freshwater input and nutrient depletion were likely responsible for a decrease in microphytoplankton (median annual abundance over 60% lower than the climatologic median) and cyanobacteria (up to 47% lower than the climatology). Significant seasonal differences in cyanobacteria and microphytoplankton abundances (R ANOSIM  = 0.52; p < 0.05), as well as in seawater temperature and salinity (R ANOSIM  = 0.73; p < 0.05) between the study period and the climatology were highlighted. The late spring diatom bloom was not reflected in high photosynthetic rates whereas an unusually high primary production was estimated in November (7.11 ± 1.01 μgC L -1  h -1 ), when a mucilage event occurred due to very stable atmospheric and oceanographic conditions. The typical seasonal succession of pelagic phototrophs (micro-, nanophytoplankton and cyanobacteria) was altered since an exceptional cyanobacteria bloom first developed in April, followed by a delayed diatom bloom in May., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Biological Traits Analysis (BTA) was used to identify functional features of infaunal polychaete assemblages associated with contamination in two Italian coastal areas: the harbour of Trieste (Adriatic Sea) and the Mar Piccolo of Taranto (Ionian Sea). The analysis was performed on 103 taxa, collected at four stations in each area. The two areas differed in species composition. The low diversity and the presence of stress-tolerant species in more polluted sites were not reflected in functional diversity, due to species contributing little to community functions or being functionally redundant. Sand and clay fractions were significant drivers of trait category expressions, however other environmental parameters (depth, total organic carbon and nitrogen, and Hg in sediments) influenced traits composition. Motile was the prevalent trait in environments with coarse sediments, and tube-builder were related to fine-grained ones. Motile, endobenthic and burrower were essential traits for living in contaminated sediments. Epibenthic and sessile polychaetes dominated at stations subjected to high organic loads. BTA offers an integrative approach to detect functional adaptations to contaminated sediments and multiple anthropogenic stressors., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

The effects of long-line mussel farming on microphytobenthos were investigated in a coastal area of the Gulf of Trieste. Sediment grain-size, organic matter content, microalgal abundance and community structure were analysed in September 2008 and March 2009. Four areas were sampled: a twenty-year farm, a four-year farm, a disused farm and a reference site. Principal component analysis (PCA) highlighted a decreasing gradient of organic matter content from the twenty-year farm to the control. Mussel farming seemed to influence microphytobenthic abundance with higher densities in the oldest farm. Three genera were dominant; Navicula and Gyrosigma seemed to be stimulated by the organic load under the active farms while we infer that Nitzschia proliferation was limited by shade caused by mussel ropes. In the PCA, samplings of the disused farm were placed in-between the still active farms and the control, indicating the partial recovery occurred in this site., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

• Benthic foraminifera were investigated in three Mediterranean tourist marinas. • Foraminifera responded to metal contamination ascribed to hull cleaning. • Different indices were tested: FAI, d, H′, ES(100), Exp(H′bc), fAMBI. • Marina's shape influences the accumulation of metals derived from careening activities. • Exp(H′b,c) and fAMBI resulted the most informative tools for the monitoring of marinas. Living benthic foraminifera were investigated in three tourist marinas of the Central Adriatic in order to test the suitability of these organisms for a quick and cost-effective assessment of the ecological quality status (EcoQS). Local high concentrations of biocidal metals (Cu, Zn, Cr, Sn, Ni and Pb) were measured in the sediments nearby the boathouse areas, i.e. where the careening activity takes place, suggesting that the accumulation of current and past antifouling residues is the main source of pollution in these particular maritime spaces. Factors such as the capacity of the marina, its shape as well as the location of the boathouse area concur to the degree of antifouling residues accumulation. Foraminifera responded to the different environmental conditions and to metal contamination in terms of abundance and species composition. At the boathouse stations these organisms were scarcely numerous and no living specimen was observed in the most polluted sediments. Three categories of indices were tested based on: (1) the percentages of abnormal tests, (2) biodiversity and (3) the sensitive-tolerant species occurrence (i.e. Foram-AMBI). The most diverse assemblage was observed at intermediate metal levels and seemed to be influenced by other environmental factors such as the presence of submerged vegetation that likely provides additional resources and increased heterogeneity. Unexpectedly, the station with the lowest metal levels was characterized by the least biodiverse assemblage. Notwithstanding, among the few species observed, at this site the dominant one was the sole species encountered in the present study that is recognized as sensitive, i.e. Ammonia parkinsoniana. Consequently, while the diversity indices provided very low values, Foram-AMBI outputs indicated the presence of an assemblage not exclusively dominated by opportunistic taxa. This result suggests a complementarity of these two categories of indices that should be taken into account for an accurate EcoQS assessment of tourist marinas. [ABSTRACT FROM AUTHOR]