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This paper describes the results of the activities performed during the project PONa3_00363 I-AMICA (High Technology Infrastructure for Climate and Environment Monitoring; www.i-amica.it), as part of the activities of Development Objective 4.4 (Processes of the biosphere-hydrosphere interface and features of coastal ecosystems). Through the strengthening of scientific-technological infrastructure and equipment, I-AMICA was planned to increase the observational capacity of the monitoring of marine coastal ecosystems, particularly vulnerable in the sensitive Mediterranean area and strictly connected to the natural and anthropic continental system. For this reason research activities were mainly focused on the neritic environment adjacent to the shelf area of the Volturno River mouth (Gulf of Gaeta - central part of the Tyrrhenian Sea). Advanced knowledge on the dynamics in time of marine coastal ecosystems, in relation to the physical, chemical and biological processes that characterize their habitat, were acquired while new methods of integrated monitoring, in relation to the specific characteristics of the study area, were tested. Particular attention was given to the identification of bio-indicators in water column and sediment at sea floor. The monitoring was also integrated by studies on the shoreline changes, seismic stratigraphy of deltaic deposits and by sedimentology and morpho-bathymetry of the seabed., Vengono presentati i risultati dell’attività di monitoraggio svolta nel corso del progetto PONa3_00363 I-AMICA (Infrastruttura di Alta tecnologia per il Monitoraggio Integrato Climatico-Ambientale; www.i-amica.it/i-amica/), nell’ambito delle attività relative all’Obiettivo Realizzativo 4.4 (Processi di interfaccia biosfera-idrosfera e funzionalità degli ecosistemi costieri). L’attività, che ha avuto come scopo l’acquisizione di conoscenze avanzate sulle dinamiche e/o variazioni nel tempo degli ecosistemi marino-costieri in relazione ai processi fisici, chimici e biologici che caratterizzano il loro habitat, si è sviluppata attraverso la sperimentazione di nuove metodologie di monitoraggio in relazione alle specifiche caratteristiche dell’area marino-costiera prospiciente la foce del fiume Volturno (Golfo di Gaeta). In particolare, oltre che sulle tecniche di monitoraggio classiche, lo studio si è principalmente focalizzato sulla acquisizione ed interpretazione di dati ambientali sia in colonna d’acqua che nei sedimenti a fondo mare e sulla identificazione di specie e/o associazioni di specie significative (bio-indicatori) da un punto di vista ambientale ed indicative dello stato di salute del sistema costiero. Poiché il sistema costiero rappresenta una struttura naturale complessa e delicata, la cui evoluzione è il risultato di delicati equilibri fisici, chimici e biologici, fortemente condizionabili dagli interventi antropici, l’attività di monitoraggio è stata integrata da studi sulla variazione della linea di costa, da studi sismostratigrafici della piana deltizia, sedimentologici e morfo-batimetrici dei fondali.

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.

Altres ajuts: Unidad de excelencia María de Maeztu CEX2019-000940-M; Universidade de Vigo's programme to attract excellent research talent (RR04092017) The eastern Mediterranean Sea lies under the influence of high- and low-latitude climatic systems. The northern part of the basin is affected by Atlantic depressions and continental and polar air masses that promote intermediate and deep-water formation. The southern part is influenced by subtropical conditions and monsoon activity. Monsoon intensification results in enhanced freshwater discharge from the Nile River and other (now dry) systems along the North African margin. This freshwater influx into the Mediterranean Sea reduces surface water buoyancy loss. Disentangling the influences of these diverse climatic forcings is hindered by inherent proxy data limitations and by interactions between the climatic forcings. Here we use a wealth of published and new paleoclimate records across Termination II to understand the impacts of the higher latitude and subtropical/monsoon climate influences on coccolithophore ecology and holococcolith preservation in Aegean Sea sediment core LC21. We then use these findingsto interpret coccolith assemblage variations at Ocean Drilling Program Site 967 (located nearby LC21, at the Eratosthenes Seamount) during multiple glacial-interglacial cycles across the Middle Pleistocene (marine isotopic stages 14-9). The LC21 analysis suggests that holococcolith preservation was enhanced during Heinrich Stadial 11 (∼133 ka) and cold spell C26 (∼119 ka). These two events have been previously linked to cold conditions in the North Atlantic and Atlantic Meridional Overturning Circulation weakening. We propose that associated atmospheric perturbations over the Mediterranean Sea promoted deep-water formation, and thus holococcolith preservation. Similarly, in the Middle Pleistocene (MIS 14-9) of Site 967, we observe temporal coincidence between ten episodes of enhanced holococcolith preservation and episodes of Atlantic Meridional Overturning Circulation slowdown. In Site 967, we also identified repeated fluctuations in placoliths and in Florisphaera profunda, which indicate nutricline depth variations. The development of a deep chlorophyll maximum is associated with the North Africa and wet phases, as recently observed using elemental proxy records at Site 967, during the deposition of sapropel layers. A further deep chlorophyll maximum development is identified during MISs 12 and 10, as a result of pycnocline and nutricline shoaling within the lower part of the photic zone due to glacial sea-level lowering and water mass transport reduction at both the Gibraltar and Sicily Straits. Finally, enhanced holococcolith preservation during cold/dry events is clearly correlated to weakened monsoon activity in both Africa and Asia.