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We present a high-resolution paleoclimatic and paleoenvironmental reconstruction of the last five millennia from a shallow water marine sedimentary record from the central Tyrrhenian Sea (Gulf of Gaeta) using planktonic foraminifera, pollen, oxygen stable isotope, tephrostratigrapy and magnetostratigrapy. This multiproxy approach allows to evidence and characterize nine time intervals associated with archaeological/cultural periods: Eneolithic (base of the core–ca. 2410 BCE), Early Bronze Age (ca. 2410 BCE–ca. 1900 BCE), Middle Bronze Age–Iron Age (ca. 1900 BCE–ca. 500 BCE), Roman Period (ca. 500 BCE–ca. 550 CE), Dark Age (ca. 550 CE–ca. 860 CE), Medieval Climate Anomaly (ca. 860 CE–ca. 1250 CE), Little Ice Age (ca. 1250 CE–ca. 1850 CE), Industrial Period (ca. 1850 CE–ca. 1950 CE), Modern Warm Period (ca. 1950 CE–present day). The reconstructed climatic evolution in the investigated sedimentary succession is coherent with the short-term climate variability documented at the Mediterranean scale. By integrating the planktonic foraminiferal turnover from carnivorous to herbivorous–opportunistic species, the oxygen isotope record and the pollen distribution, we document important modification from the onset of the Roman Period to the present-day. From ca. 500 CE upwards the documentation of the cooling trend punctuated by climate variability at secular scale evidenced by the short-term δ 18 O is very detailed. We hypothesise that the present day warm conditions started from the end of cold Maunder event. Additionally, we provide that the North Atlantic Oscillation (NAO) directly affected the central Mediterranean region during the investigated time interval. [ABSTRACT FROM AUTHOR]

The analyses of water and sediment samples, collected at 24 marine stations in a coastal area (Gulf of Gaeta, central Tyrrhenian Sea) during a three year survey (2012–2014), have improved our knowledge of coccolithophore ecology in the Mediterranean neritic domain. A comparison between the results and the oceanographic data has highlighted the ecology of the considered groups, and quantified the relationship between the community structures and the environmental parameters. The coccosphere concentration measured in the Gulf of Gaeta is extremely variable over the sampling periods (min:64 l −1 ; max:2.4*10 5  l −1 ), and comparable with data from other Mediterranean sites. Placolith-bearing taxa are the dominant group of the living communities. The concentration and distribution of Emiliania huxleyi is controlled by the distance from the coast and the Volturno River runoff. The K-strategist taxa are an important component of the summer nannoplankton in the upper 15 m and in the sediment samples. These taxa are also related to summer oligotrophic warm waters and low turbidity as well. The opportunistic behaviour of Helicosphaera carteri is confirmed and is related to moderately elevated nutrient levels and also tolerance to low salinity and terrigenous input. Nevertheless, our findings raise some questions on the reliability of H. carteri as a low salinity proxy. Overall, the sediment assemblages reflect the composition and the temporal distribution of the living communities. The occurrence and distribution of abundant reworked coccoliths, both in water and sediments, provides useful information about coastal dynamics and confirm their use as a reliable runoff proxy. [ABSTRACT FROM AUTHOR]

We present the results of a high resolution study carried out on a shallow water sediment core, recovered in the central Tyrrhenian Sea to reconstruct the runoff history of the catchment basin of Volturno and Garigliano rivers (Gulf of Gaeta, Italy), over the past ~ 400 years. We compared the abundance distribution pattern of Reworked Coccoliths to the surface runoff model simulation for the Volturno and Garigliano hydrographic river basins, the Global Historical Climatology Network index, the Palmer drought severity index, the Tevere river discharge anomaly, the average summer rainfall in Southern Italy and the reconstructed North Atlantic Oscillation signal. This comparison suggested that the biotic signal of the Reworked Coccoliths may be used to detect climatic events from local to “global” scale. The calcareous nannofossil assemblages as well as their diversity index are modulated by oscillation in solar activity, where minima in solar activity correspond to minima calcareous nannofossil diversity and vice versa . In particular, the antiphase correlation between the abundance of Reworked Coccoliths and the North Atlantic Oscillation index, which modulates winter precipitation, suggests that this biotic index could be used as a reliable proxy to reconstruct the variations in the hydrographic basin runoff of the Volturno and Garigliano rivers. In addition, power spectral and wavelet analysis carried out on both signals documented the occurrence of climatic cycles of the duration of about 95 yr. From 1900 AD upwards, a turnover in the periodicity from 95 yr climatic cycles to 22–26 yr cycles occurred in the Reworked Coccoliths signal, suggesting a strong control of solar forcing (Hale cycle) over the last century. [ABSTRACT FROM AUTHOR]

We present the distribution pattern of living and surface sediment coccolithophores, the main phytoplankton calcifying group, from 22 stations set in a neritic environment (from 10 to 50 m water depth), adjacent to the shelf area of the Volturno River mouth (Gulf of Gaeta - central part of the Tyrrhenian Sea). The survey conducted in June 2012 included five transects perpendicular to the coast, which enabled us to provide indications on the structure of calcareous phytoplankton associations in relation to coastal dynamics and the Volturno River runoff. The total number of coccospheres ranged from 15 to 64 * 10³* l-1 coccolithophores. Emiliania huxleyi dominates the assemblages, followed by Rhabdosphaera xiphos, holococcolithophores and Syracosphaera pulchra. The coccolithophore community shows a typical vertical zonation, with K-strategist taxa in the upper 15 m and the deep community developed down to 40 m. The local water circulation significantly affects the spatial and vertical distribution of coccolithophores. The river discharge influences the distribution of coccolithophore taxa, resulting in a north-south gradient. In the northern sector, outside the influence of the Volturno River, the high values of R. xiphos suggest a negative correlation with river runoff. The surface sediment assemblages reflect the overall composition of the living coccolithophore communities. The distribution of abundant reworked species, both in water and sediment, provides useful information about coastal dynamics and sediment transport in the study area. [ABSTRACT FROM AUTHOR]