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Abstract: Four representative paleosols in the Plio-Pleistocene alluvial fan of the River Tirso (Central-Western Sardinia, Italy) were studied for paleoenvironmental information, to describe the sedimentology of the alluvial fan, and to define a relative chronological framework for the fan. The representative depositional units and associated paleosols were characterised by fieldwork, physical, chemical, and mineralogical analyses. Pedogenesis was mostly driven by the time and climate factors. In the proximal fan location, pedogenesis was initially influenced by a warm subtropical-tropical climate of the Late Pliocene and subsequently by warm and humid interglacial phases of the Pleistocene. These phases were also responsible for soil formation in the middle fan. In the distal reaches of the fan, pedogenesis was driven by the different climatic pulses of the Late Pleistocene Tyrrhenian interglacial (MIS 5). Pleistocene eustatic sea level changes directly influenced the lowest elevations of the middle fan and the distal fan. Erosion and soil truncation mainly occurred in the proximal fan and at the highest elevations of the middle fan during glacial phases. [Copyright &y& Elsevier]

Microplastics debris (<5 mm) are increasingly abundant in the marine environment, therefore, potentially becoming a growing threat for different marine organisms. Through aquatic animals, these can enter in the human food chain, and can be perceived as a risk for consumers' health. Different studies report the presence of particles in marketable shellfish including the world wide commercially grown Pacific oyster Magallana gigas (Thunberg, 1793). The aim of this study is to examine the potential risk of microplastics entering in the human food chain through this shellfish species, investigating the dynamics of the uptake, egestion (faeces) and rejection (pseudofaeces) of microplastics in Pacific oysters under controlled conditions. M. gigas collected from a farm in the San Teodoro lagoon (Italy), were exposed to 60 fluorescent orange polystyrene particles L -1 of known sizes (100, 250 and 500 μm). The uptake of each particle size was 19.4 ± 1.1%, 19.4 ± 2% and 12.9 ± 2% respectively. After exposure M. gigas were left to depurate for 72 h, during which 84.6 ± 2% of the particles taken up were released whilst 15.4 ± 2% were retained inside the shell cavity. No microplastic particles were found in the animals' soft tissues. The results of this study, suggest that depuration is an effective method to reduce presence of large microplastic particles, in the size range 100-500 μm, in M. gigas. Importantly, the data suggests that the burden that could theoretically be up taken by consumers from these shellfish is negligible when compared to other routes., (Copyright © 2019 Elsevier Ltd. All rights reserved.)