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By examining the sedimentary records from two new cores collected from the Sabrina Coast slope, we have developed an age model spanning from the late Pliocene to the present. From multiproxy sediment analyses of the piston and kasten core, PC03, and KC03, collected during the IN2017_V01 survey on the Sabrina Coast (East Antarctica) offshore the Totten Glacier, we here present the outcomes derived within the seismostratigraphic record coupled with the sedimentological, geochemical paleomagnetic, and biostratigraphic contexts. Our results highlight that the area has been affected by recurrent sediment slides facilitated by siliceous deposits, both biogenic and from an unprecedented tephra layer, during some of the major paleoclimatological events of the late Pliocene. Diatoms contributed not only to the biostratigraphic and depositional environmental definition but also to the instability of the slope, together with the tephra layer, as documented offshore the Sabrina–Aurora Basin for the first time.

Environmental contamination has become a global problem of increasing intensity due to the exponential growth of industrialization. One main debated issue is the metal contamination of rivers receiving Acid Mine Drainage (AMD) from active/abandoned mines. In order to assess the quality of lotic systems, diatoms are commonly used, as their assemblage modifies on the basis of changes in environmental parameters. Benthic diatom changes were analyzed along the metal-impacted Gromolo Torrent (Liguria, NW Italy) with the aim of understanding the effects of input from the abandoned Libiola Cu mine. The results support the hypothesis that metals from AMD lead to massive changes in diatoms, resulting in low biological diversity and in a shift of dominance, passing from the genera Cymbella and Cocconeis to more tolerant and opportunistic species, such as Achnanthidium minutissimum and Fragilaria rumpens. The high concentrations of labile metals, measured through Diffusion Gradients in Thin-films (DGT) immediately downstream of the two AMD inputs in the torrent, corresponded to a sudden decrease in the presence of diatoms, indicating the possible reaching of acute toxic levels. In particular, A. minutissimum dominated the mining area and was positively correlated with Cu and Zn; whereas F. rumpens bloomed downstream of this area, where the metal content was diluted, and was positively correlated with As and Pb. Finally, an important abundance of Nitzschia palea and teratological forms of A. minutissimum and F. rumpens were observed downstream from the mine, indicating that metals may have an important impact on diatoms up to the torrent mouth., (Copyright © 2018. Published by Elsevier B.V.)

Fungi include a vast group of eukaryotic organisms able to colonise different natural, anthropised and extreme environments, including marine areas contaminated by metals. The present study aims to give a first multidisciplinary characterisation of marine bottom sediments contaminated by metals (Cd, Co, Cr, Cu, Ni, and Zn), originating in the water leakage from an abandoned Fe-Cu sulphide mine (Libiola, north-western Italy), and evaluate how the chemical and physical parameters of water and sediments may affect the benthic fungal communities. Our preliminary results showed the high mycodiversity of the marine sediments studied (13 genera and 23 species of marine fungi isolated), and the great physiological adaptability that this mycobiota evolved in reaction to the effects of the ecotoxic bottom sediment contamination, and associated changes in the seawater parameters., (Copyright © 2017 Elsevier Ltd. All rights reserved.)