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A new marine pollen record from SE Sicily is presented. The pollen study was done at a sub-decadal resolution to assess the role and extent of human impact in driving regional environmental and land cover changes over the last four hundred years. The combination of palaeoecological evidence and historical documents provides a detailed report of the main ecological dynamics in relation to socio-economic events, past land use, and land management regulations in Sicily. Our palaeovegetational reconstruction reveals a remarkably stable landscape, preserved by traditional land use practices that have persisted through the long-lasting feudal history of Sicily. After centuries of human-induced environmental stability, an abrupt change in vegetation structure occurred around 1950 AD, reflecting the modern land use policies and agricultural reforms following the Second World War. This vegetational breakpoint in SE Sicily corresponds to a suggested date for the onset of the Anthropocene. (C) 2021 Elsevier B.V. All rights reserved.

Here we present the biostratigraphic and chronostratigraphic framework of a number of selected diatomaceous laminated intervals from the Crotone Basin (Calabria, Southern Italy). These layers, which we consider correlative to the Eastern Mediterranean Sapropel Layers, range in age from the early Piacenzian to the Gelasian, and show surprising thicknesses, suggesting that they were probably laid down in a landlocked, overfed basin. Specifically, a thick laminite from the surroundings of Cropani (Catanzaro) can be ascribed to nannofossil biozone MNN 16a and planktonic foraminifera biozone MPL 4b (lower Piacenzian) according to the Mediterranean calcareous plankton biostratigraphic zonations. Two laminites from the “Muto” Section (Botricello-Cutro road, Crotone), belong to MPL 5a and MNN 16b/17 Zones (upper Piacenzian). A very thick laminite from the “Timpone dell’Inferno” badland area (near Termine Grosso, Catanzaro), belong to MPL 5b and MNN 18 Zones (middle-upper Gelasian). These biostratigraphic constraints provide a first contribution to a comprehensive paleoenvironmental reconstruction.

Marine deposits from the Palermo Plain were historically relevant for the Quaternary Period definition. Here we show lithostratigraphic, biostratigraphic and chronostratigraphic data collected on three boreholes in the Palermo historical centre that recovered 36.8, 42.0 and 52.0 metres of sediments overlaying the Numidian Flysch. Marine sedimentary sequences span from the Calabrian Stage (calcareous nannofossil Zone MNN 19d) to the Middle Pleistocene (dominance of medium-sized gephyrocapsids within the MNN 19f Zone) and also include a short Holocene depositional event. Calcareous nannofossil, benthic and planktonic foraminifera assemblages point to a shallow coastal environment, possibly < 50 m deep. This study highlights the need of a modern and reliable stratigraphic interpretation of lithotypes, to identify stratigraphic gaps and to draw deep geological structures in an area extremely vulnerable to seismic and hydrogeological hazard.

The northeastern part of Sicily is characterized by intense seismic activity. Several systems of faults have been recognized in Pliocene and Pleistocene sediments in the area and, in fact, estimates of uplift rates are among the highest recorded in Sicily and south Italy. We examined calcareous nannofossil and benthic and planktonic foraminifera assemblages from pelitic sediments of the Contrada Zura section (Barcellona Pozzo di Gotto Basin, Furnari village, Messina). The occurrence of Emiliania huxleyi, a coccolithophore species which appeared in the oceanic record about 270,000 years ago, is witness to the uniqueness of this outcrop, while the planktonic/benthic foraminifera ratio indicates a deep (slope) environment, in agreement with previous observations on macrobenthic and ostracod paleo-communities. Independently from the numerical estimate of the paleo-depth, there is little doubt that the occurrence of E. huxleyi in such sediments might be explained by exceptional uplift rates. Since resulting uplift rate estimates, between 3.2 and 5.5 mm/year, exceeded by far the regional, longer-term, vertical tectonic motion, we argue that a major contribution of coseismic displacement along active faults occurred in the Furnari area.

The Little Ice Age (LIA) is the last episode of a series of Holocene climatic anomalies. There is still little knowledge on the response of the marine environment to the pronounced cooling of the LIA and to the transition towards the 20th century global warming. Here we present decadal-scale coccolithophore data from four short cores recovered from the central Mediterranean Sea (northern Sicily Channel and Tyrrhenian Sea), which on the basis of 210Pb activity span the last 200–350 years. The lowermost part of the record of one of the cores from the Sicily Channel, Station 407, which extends down to 1650 AD, is characterized by drastic changes in productivity. Specifically, below 1850 AD, the decrease in abundance of F. profunda and the increase of placoliths, suggest increased productivity. The chronology of this change is related to the main phase of the Little Ice Age, which might have impacted the hydrography of the southern coast of Sicily and promoted vertical mixing in the water column. The comparison with climatic forcings points out the importance of stronger and prolonged northerly winds, together with decreased solar irradiance.

A sedimentary sequence spanning Marine Isotope Stage (MIS) 6 to MIS 2 in core LC07, recovered in the central Mediterranean, has been investigated in order to produce a high-resolution paleoceanographic reconstruction. The changes in productivity deduced from calcareous plankton relative abundances and independently confirmed by the Ba XS fluctuations are linked to the stability of the water column which is mainly controlled by the water mass temperature. During glacial intervals, productivity was generally enhanced. Oligotrophic and warmer water masses with a deepened seasonal thermocline can be inferred for most of MIS5. The magnetic properties of the sediment show increased occurrences of North Africa dust in the central Mediterranean during cold phases, likely as a consequence of a more efficient erosive process triggered by southward displacement of the intertropical convergence zone. Although increases in both productivity and Saharan dust occurred during cold periods, the atmospheric inputs do not seem to contribute significantly to the fertilization of primary producers. A Shannon Index curve has been used to tentatively synthesize the variations of calcareous nannofossil assemblages through the last 150 kyr. The assemblage diversity sharply increased coincident with the transition from the penultimate glacial to the last interglacial, subsequently low diversity was gradually reached again in the last glacial.

The Gulf of Sirte is a largely unexplored area in the southernmost Mediterranean Sea.We are presenting here 2008 summer data on the distribution pattern of living coccolithophores, a main phytoplankton calcifying group, in 105 samples from 20 stations. The survey includes coastal and offshore stations, enabling us to provide indications on the dynamics of phytoplankton productivity in relation to oceanographic processes. The total coccosphere concentrations show higher values in the offshore stations and lower ones for coastal sites. Umbellosphaera tenuis, Emiliania huxleyi, Florisphaera profunda, Syracosphaera pulchra HOL (Calyptrosphaera oblonga) and Rhabdosphaera spp. dominate the assemblages. The coccolithophore community shows the typical vertical zonation, with K-strategist taxa (among others U. tenuis, Rhabdosphaera spp. and Discosphaera tubifera) in the upper 75 meters depth and Lower Photic Zone taxa, dominated by F. profunda, below. The latter species shows its maximum development in the Deep Chlorophyll Maximum layer, which occurs in the upper part of the Levantine Intermediate Water, where the nutrient content is higher than in the overlying layers. The mesoscale oceanographic circulation significantly affects the spatial and vertical distribution of coccolithophores, with the thermocline and halocline depth shaping the vertical zonation of coccolithophore taxa and resulting in a strong lateral gradient within the gulf: in the eastern sector, under the influence of the Gulf of Sirte anticyclone, the DCM is deeper and so is the occurrence of K-strategist taxa and F. profunda.