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The Lagoon of Venice was formed during the Late Holocene transgression and anthropogenic remains are common within its sedimentary sequences. This study is based on the foraminiferal association of 58 samples from 7 cores obtained from salt marshes north of Venice. Below horizons of lagoonal origin, these samples reveal the presence of faunas with Trochammina inflata (Montagu) and Helenina anderseni (Warren) which indicate conditions that are characteristic of present-day salt marshes. Foraminiferal faunas can identify the different lagoonal environments and indicate the relative position of the various horizons with respect to sea level. Faunas obtained from the lower section of the cores are analogous to present-day assemblages and they indicate, below a transgressive phase, the existence of buried ancient salt marshes occupied by human settlements. The absolute age of these horizons indicates that the establishment of human settlements is much older than previously thought and that the average rate of Holocene relative sea level rise for the last 5000 years is of the order of 1.2 mm/yr. The formation of these salt marshes, and their subsequent submergence, occurred with rates of accretion and subsidence markedly variable and with occasional erosional phases. This study also shows that, within the present lagoonal environment, together with erosional processes there are areas of accumulation with the formation of new salt marshes. [Copyright &y& Elsevier]

A ca. 950 m thick succession that was continuously cored in 1971 in Venice has been revisited, in order to reconstruct the environmental history of the Venice area since about 2.15 Ma. Magnetic polarity stratigraphy, integrated with refined calcareous nannofossil biostratigraphy, provides a firm chronostratigraphic framing of the succession. In order to improve the chronological resolution, we derived astrochronological refinements in the lower Pleistocene sapropel-bearing interval by a comparison with other time-correlative sections in the Mediterranean. The pollen record is used as a proxy of climatic changes and as an indirect tool in the chronological reconstruction in the upper part of the succession. The following history has been inferred: (1) in the late Gelasian (late Pliocene), the depositional area was a strongly subsiding shelf which shoaled to near sea level; (2) following a hiatus of a minimum duration of 0.2 Myr, encompassing most of the Olduvai Subchron, the shelf rapidly drowned to bathyal depths over the early Pleistocene (biozones MNN 19a to 19e: from 1.947 Ma to 0.96 Ma). This interval was characterized by starved sedimentation (less than 10 cm/kyr), represented by hemipelagic muds interbedded with sapropel layers; (3) during most of biozone MNN19f (Pseudoemiliania lacunosa Zone, 0.96–0.42 Ma) a thick package of turbidites was laid down as a result of massive terrigenous input from the eastern Southern Alps; (4) later, in the middle part of Chron 1n (Brunhes), deltaic sedimentation, primarily related to the progradation of the paleo-Po system, led to the progressive infill of the basin. This progradational episode was a major building phase, and ended with the first appearance of continental sediments, tentatively correlated with marine oxygen isotope substage 8.4; (5) the upper part of the succession shows a cyclic organization, with an upward increasing amount of marginal-marine and subaerial deposits. In this interval the Venice area was below sea level during glacioeustatic highstands but became emergent during subsequent major glacioeustatic lowstands. Pollen data support an overall good correspondence of continental sediment packages of sequences with glacial conditions and of maximum flooding intervals with interglacial conditions. [Copyright &y& Elsevier]

The rapid expansion of the ornamental aquaculture industry over the past decades has resulted in a concomitant increase in the use of antibiotics to combat infectious diseases. The aim of this study was to assess the possible role of ornamental fish in the translocation of antibiotic resistant bacteria, with possible consequences for aquarium and public health. We assessed the prevalence of bacterial infections and the antibiotic resistance profile of bacteria isolated from 134 ornamental fish imported into northwest Italy during two years of monitoring. Ornamental fish analyzed were imported mainly from Singapore (40%) and Israel (20%), followed by Thailand (13%), Sri Lanka (12%), Czech Republic (7%), Vietnam (5%) and Indonesia (3%). The most commonly imported fish were freshwater species, particularly those belonging to the Poeciliidae family. Bacteriological exam was positive in 68% of the fish examined. The most frequently isolated bacterium was Aeromonas sobria (37%). Bacteria showed resistance against lincomycin, ampicillin, oxytetracycline and tetracycline. Sensitivity was found for florfenicol, chloramphenicol, gentamicin, and trimethoprim/sulfamethoxazole. Odds ratio (OR) values were calculated as a measure of the association between antibiotic resistance of A. sobria and selected factors (country of origin, fish family and fish species), considering Thailand, Poeciliidae and Poecilia reticulata as control cases. Higher values were found for Vietnam (OR 5.6) and Xiphophorus helleri and X. maculatus (OR 3.0 and 3.7 respectively). Our findings underline the need to improve targeted surveillance of antimicrobial resistance and prevent the translocation of resistant or multi-resistant bacterial strains in ornamental fish, especially in fish imported from countries where surveillance is limited or lacking., Competing Interests: Declaration of Competing Interest None., (Copyright © 2019 Elsevier B.V. All rights reserved.)