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The history of vegetation in the Italian peninsula during the last 2000 years was shaped by a complex interplay of several factors, including the history of human societies, changes in land use, and the succession of climate events. In order to disentangle these factors, we present a multidisciplinary record from a marine core collected in the Gulf of Gaeta, interpreted in the light of other palaeoenvironmental records from Tyrrhenian Italy. Pollen records, complemented by new data on Non-Pollen Palynomorphs (NPPs) and microcharcoal, are used to reconstruct changes in the vegetational landscape, stock-breeding activities, fire, and land use. Foraminiferal and oxygen isotope data provide independent information on climate changes. NAO-index and sunspot data support the interpretation of changes in atmospheric circulation. In this paper, by examining the effect of climate and human activity on the landscape during a series of periods of the last 2000 years, representing cultural or climate phases (Roman Period, Dark Ages, Medieval Climate Anomaly, Little Ice Age, and Modern Period), we found that human impact produced a general and progressive decline of forest vegetation. However, irrespective of the societal cultural phase, forest declines occurred when negative NAO oscillations induced dry climate, especially during sunspot minima

A new high resolution pollen, planktonic foraminiferal and oxygen isotopes record from a shallow water marine sedimentary core from the central Tyrrhenian Sea (Gulf of Gaeta) provides information on vegetation and climate changes occurred in the central Mediterranean region during the last 5000 cal. years BP (Margaritelli et al., 2016). Nine time intervals characterized by clear vegetation and climate changes and associated with archaeological/cultural periods have been described: Eneolithic (ca. 3080- ca. 2410 BC), Early Bronze Age (ca. 2410 BC–ca. 1900 BC), Middle Bronze Age-Iron Age (ca. 1900 BC–ca. 500 BC), Roman Period (ca. 500 BC–ca. 550 AD), Dark Age (ca. 550 AD–ca. 860 AD), Medieval Climate Anomaly (ca. 860 AD–ca. 1250 AD), Little Ice Age (ca. 1250 AD–ca. 1850 AD), Industrial Period (ca. 1850 AD–ca. 1950 AD), Modern Warm Period (ca. 1950 AD–present day). In this paper we aim to characterize the major vegetation changes influenced by climate and human impact.

This study presents the reconstructed evolution of sea surface conditions in the central-western Mediterranean Sea during the late Holocene (2700 years) from a set of multi-proxy records as measured on five short sediment cores from two sites north of Minorca (cores MINMC06 and HER-MC-MR3). Sea surface temperatures (SSTs) from alkenones and Globigerina bulloides Mg / Ca ratios are combined with δ18O measurements in order to reconstruct changes in the regional evaporation–precipitation (E–P) balance. We also revisit the G. bulloides Mg / Ca–SST calibration and re-adjusted it based on a set of core-top measurements from the western Mediterranean Sea. Modern regional oceanographic data indicate that Globigerina bulloides Mg / Ca is mainly controlled by seasonal spring SST conditions, related to the April–May primary productivity bloom in the region. In contrast, the alkenone–SST signal represents an integration of the annual signal. The construction of a robust chronological framework in the region allows for the synchronization of the different core sites and the construction of “stacked” proxy records in order to identify the most significant climatic variability patterns. The warmest sustained period occurred during the Roman Period (RP), which was immediately followed by a general cooling trend interrupted by several centennial-scale oscillations. We propose that this general cooling trend could be controlled by changes in the annual mean insolation. Even though some particularly warm SST intervals took place during the Medieval Climate Anomaly (MCA), the Little Ice Age (LIA) was markedly unstable, with some very cold SST events mostly during its second half. Finally, proxy records for the last centuries suggest that relatively low E–P ratios and cold SSTs dominated during negative North Atlantic Oscillation (NAO) phases, although SSTs seem to present a positive connection with the Atlantic Multidecadal Oscillation (AMO) index.

International audience; Because of their location at the interface between sea and emerged lands, so-called transitional environments are characterized by strong spatial and temporal variability in terms of sedimentological, physicochemical, and geochemical parameters. An increasing number of studies put forward the use of bioindicators as a tool for environmental monitoring. However, the sensitivity to these environmental parameters is commonly tested separately, even though it is known that interactions are numerous within this complex ecosystem. An integrated methodological study was conducted in Lake Varano (Italy). On the basis of 45 spatially distributed samples throughout the area and selected environmental parameters (trace elements, organic matter, clay mineral assemblages, grain size of sediment, and water characteristics), four factors are identified. The Lake Varano ecosystem is predominantly influenced by terrigenous inputs (first-order factor). The clastic fractions of the sediments supply a large range of trace elements, occasionally in relatively high concentrations. Under such circumstances, despite occasionally exceeding of threshold limits, the trace element pollution can generally be ruled out. The organic content combined with depth is the second key factor. In Lake Varano, the organic content is high and may lead to seasonal eutrophication. As a third-order factor, although only analyzed once, oxygen, ORP, salinity, and pH gradients show that foraminiferal diversity is positively influenced by more saline conditions. The fourth-order factor is the sediment size. To conclude, this paper illustrates the interest in and need to conduct a detailed, integrated, sedimentological study of a site prior to any examination of its ecological status (possible occurrences of sources of pollution).