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The magnitude and rate of Late Pleistocene-Holocene vertical tectonic movements offshore of the Capo Vaticano Promontory (western Calabria, southern Italy) have been measured on the basis of the present-day depth variations of the edges of submerged depositional terraces (and associated abrasion platforms) that formed below the storm-wave base, during the sea level stillstand of the Last Glacial Maximum (LGM). These depositional features, represented by submerged prograding wedges and an associated terrace-shaped upper boundary, have been identified in high-resolution seismic reflection profiles acquired along the continental shelf and the upper slope of the promontory, and are referred to in this study as "Lowstand Infralittoral Prograding Wedges (LIPWs)". Our new data and methods provide evidence that LIPWs can be used as geomorphological indicators of vertical movements in offshore settings with well controlled uncertainty. Removal of the non-tectonic component of vertical changes using an ice-volume equivalent eustatic sea level compilation indicates similar to 11 (+/- 3.2) m of uplift and similar to 25 (+/- 3.2) m of subsidence, from southwest to northeast, along the promontory, over a distance of similar to 22 km, during the post-LGM. The resulting uplift and subsidence rates (including both regional and local components) for the last 20.350 (+/- 1.35) years are 0.54 (+/- 0.2) mm/y and 1.23 (+/- 0.25) mm/y, respectively. These results are consistent with longer-term estimates based on uplifted 215-82 ka old coastal terraces and Late Holocene shorelines. This integration of offshore and coastal markers indicates a pattern of vertical movements characterized by a marked asymmetry associated with a northeast down tilt of the Capo Vaticano Promontory. The calculated tilt rate increases by one order of magnitude during the post-LGM in respect to the time interval from 215 to 82 BP. Displacement associated with the NW-SE striking normal fault that bound the Capo Vaticano Promontory to the Gioia Tauro Basin ended in the (?) Pleistocene, and thus does not contribute to the tilt of the promontory at least during the last 215 ka. (C) 2013 Elsevier Ltd and INQUA. All rights reserved.

In the deglacial sequence of the largest end moraine system of the Italian Alps, we focused on the latest culmination of the Last Glacial Maximum, before a sudden downwasting of the piedmontane lobe occupying the modern lake basin. We obtained a robust chronology for this culmination and for the subsequent deglacial history by cross-radiocarbon dating of a proximal fluvioglacial plain and of a deglacial continuous lake sedimentation. We used reworked dinocysts to locate sources of glacial abrasion and to mark the input of glacial meltwater until depletion. The palynological record from postglacial lake sediments provided the first vegetation chronosequence directly reacting to the early Lateglacial withdrawal so far documented in the Alps. Glacier collapse occurred soon after 17.46 ± 0.2 ka cal BP, which is, the Manerba advance culmination. Basin deglaciation of several overdeepened foreland piedmont lakes on southern and northern sides of the Alps appears to be synchronous at millennial scale and near-synchronous with large-scale glacial retreat at global scale. The pioneering succession shows a first afforestation step at a median modeled age of 64 years after deglaciation, while rapid tree growth lagged 7 centuries. Between 16.4 ± 0.16 and 15.5 ± 0.16 ka cal BP, a regressive phase interrupted forest growth marking a Lateglacial phase of continental-dry climate predating GI-1. This event, spanning the most advanced phases of North-Atlantic H1, is consistently radiocarbon-framed at three deglacial lake records so far investigated on the Italian side of the Alps. Relationships with the Gschnitz stadial from the Alpine record of Lateglacial advances are discussed.

In many terrestrial species, the geographic distribution of DNA lineages was heavily affected by the climatic fluctuations that occurred during the Quaternary, although the impact of human populations, especially on harvested species, might have confounded the pattern in more recent times. In game species such signals are expected to be overshadowed by the effects of more recent management (local extinctions, introductions, translocations). Past global climate changes had a profound impact on the evolutionary history of many species and left a genetic signature which is often still detectable nowadays. The wild boar is one the most widely distributed terrestrial animals, naturally occurring from Western Europe and Northern Africa to Japan. Previous studies in European animals suggested that Iberia, Balkans and Italy played a major role as refugia during the Last Glacial Maxima (LGM), and these three areas were the main responsible for the recolonization of European continent after the LGM. This PhD dissertation investigated the geography of the genetic diversity of the European wild boar (Sus scrofa). It aims to infer how past climate influenced the current observed pattern of genetic diversity distribution of the mitochondrial DNA. A comprehensive dataset of more than 700 sequences from the hypervariable region of the mitochondrial DNA from 74 populations, covering the whole European continent (from Portugal to Russia) was used. The results confirmed the existence of a ubiquitous mitochondrial clade in Europe (E1), a highly differentiated clade exclusive of Italy (E2) and East Asian haplotypes (A) at very low frequencies, presumably introgressed from commercial pig breeds. No Near Eastern haplotype was detected. A clear south-north decreasing gradient of diversity was observed, with maximum levels hosted in presumed glacial refugia. Seven structured groups were found, with distributions highly correlated to geography. Population size within groups was generally constant through time, with only slight recent changes. Sardinia was the most differentiated population, with 64% private haplotypes. A surprising similarity between western (Iberia) and eastern Europe was observed, while central populations showed a higher affinity to the Italian gene pool. Notably, a monophyletic subclade, was shared at high frequencies by Central European (France and Germany) and Italian wild boars. To predict the distribution of the wild boar during the LGM and its relationship with the current distribution of the genetic diversity a maximum entropy method of niche modeling was used. The climate models predicted that Iberia, Balkans and Italy had great habitat suitability during the LGM, serving as refugia. Most part of Europe north to 45°N was unsuitable to the species. Italy and Iberia showed greater suitability when compared to other regions of Europe, which can indicate that these two areas may have retained large population size even during cold periods. The suitability map and the current distribution of the genetic diversity exhibited similar patterns, with northern areas showing low suitability and lower genetic diversity, while southern regions had higher values of suitability and genetic diversity. The current distribution of genetic diversity was highly influenced by past climate events, especially related to the LGM. Post-LGM colonization of the continent from southern refugia can explain the current phylogeographic patterns in the European wild boar. More recent changes to population size and gene flow could have acted more at a local scale, without a great impact on the global framework.

The stratigraphical analysis of several boreholes drilled in the Metaponto coastal plain (Basilicata region, southern Italy) highlighted the occurrence of two irregular erosional surfaces bounding three main overlapping sedimentary units. The upper unit, which base has been detected by using a geophysical method for the H/V spectral ratio (HVSR) of microtremors, fills and covers some paleovalleys that were incised during the Last Glacial Maximum (LGM). A 3D view of a main geophysical unconformity shows a surface with the occurrence of some deeper, narrow, and sinuous zones running roughly perpendicular to the present-day coastline and at depths of up to 90 m below the present-day sea level. These narrows likely correspond to the paleovalleys that developed in the region during the LGM and are buried below the Metaponto coastal plain. Some discrepancies between the geophysical and the geological data may be explained either as induced by a not well constrained projections of boreholes (from which derive the lithostratigraphic interpretations) or considering that the sedimentary models of incised-valley fills suggest the presence of different coeval deposits along dip through paleovalleys, inducing a contrast of seismic impedance readable as paleotopography rises.

The moraines of the last glacial maximum preserved on the Central Apennine massifs include many small basins (from tens to hundreds of square meters wide) draining in closed depressions. The bottom of such depressions are formed by deposits made of aeolian, colluvial and lacustrine sediments, tephra layers and soils. The sediments have been studied and interpreted in order to understand the Lateglacial and Holocene environmental variations. The small depressions were found at altitudes including between 1600 and 2100 m, in places far from the roads: therefore the sediments were sampled by means of an auger. The correlation between the sediments studied on the different massifs has been obtained using radiocarbon datings and some stratigraphic markers: a loess formed mainly by quartz, two tephra layers (the Neapolitan Yellow Tuff, dated ca. 12,000 years BP, produced by an eruption of the Phlegrean Fields volcano, and the "Duchessa" tephra, dated ca. 4000 years BP, of still unknown origin) and a volcanic minerals-rich layer (Meta layer: perhaps another tephra) covering soils dated ca. 3400-3500 years BP The sediment and soils, filling the small depressions, showed evidence of some environmental variations during the late Upper Pleistocene and Holocene. Some of such variations are a consequence of the climatic changes due to the glacial - interglacial transition, involving changes in temperature and precipitations. In particular, aeolian reworking of the Neapolitan Yellow Tuff occurred during the Younger Dryas. The Holocene, until approximately 4000 years BP, seems to have been characterized by morphological stability; beginning from that date until the present, at least three phases of instability took place, dated after 4000+4300, 3400+3500 and 1600 years BP. The morphological stability of the first part of the Holocene is testified by the presence of a soil: its development could have also been supported by the presence of silt horizons (a tephra layer and aeolian and colluvial sediments deriving from its reworking) that have remarkablly supported the expansion of the vegetation cover. In some places, one can observe that the environmental variations, pointed out by the sediments, seem to have been more frequent during the late Holocene than in the period between the Last Glacial Maximum and the fall of the Neapolitan Yellow Tuff tephra, dated ca. 12,000 years ago. As a matter of fact, before the fall of the tephra layer, the glacial till grain size and permeability did not allow for superficial running water: into the small basins the morphological stability prevailed, but the coarse grain size of the till inhibited the development of the soils; apart from the thin layer of loess, any sedimentation occurred in the basins, while, in other environments, during the same period, the climatic changes produced strong sedimentary variations. The silty tephra, penetrating between the glacial drift and covering it, could have reduced considerably the superficial permeability. This supported either the development of soils, or, in periods of reduction of the vegetation cover, the water runoff and, therefore, the erosion of the soils. Taking into consideration the Holocene environmental variations, one can observe that their number is greater during the period after 4000 years BP than in the previous one: that is due either to the infuence of climatic variations, recorded also in other environments, or, probably, to the anthropic impact on some of the studied places.

The result of the present paper can be synthetized in the following way. For the first time three morainic anphiteatres attributable to the Last Glacial Maximum (LGM) were recognized: they lie in the southern part of the Maiella Massif, outside the area of the main glacial valleys and they have been formed by glacial tongues fed by an extended ice cap that occupied the more elevated portion of that area. Moreover, some moraines and a trimline have been found, that allow a better reconstruction of the extension of the same ice cap and help to estimate the equilibrium line altitude (ELA) during the LGM. E LA during LGM was very different according to the direction of valleys and slopes: ELA has been calculated at the height of 2160 m in valleys directed toward ESE, at 1900 m in the deep-cut valleys directed toward NW, N and NE, higher than 2250 m in the ice cap on slopes directed toward SW, S and SE. The subsequent retreat phases, in the valleys of the northern portion of the massif, occurred in five steps, with ELA increasing of 140 m, 235 m, 380 m, 500÷600, 650, 740 m. According to the comparison with the Gran Sasso Massif, one can hypothesize that the Maiella's moraines formed by glaciers whose ELA was 140 m higher than during LGM, are dated to a period older than 17÷18,000 years BP; the moraine formed by glaciers with ELA 235, 380, 500÷600 m higher are younger than 16,000 and older than 10÷11,000 years BP; the moraine formed by glaciers with ELA 650 and 740 m higher must be dated to the Holocene. The youngest moraines were formed by a glacierlet, probably, during the Little Ice Age. A lot of rock glaciers has been found: the greatest amount of them developed probably during the retreat of the glaciers and the early post-glacial. However, at least at the head of the Cannella Valley, there are two rock glaciers that look very young. The recentmost has a surface less wethered and colonized by the vegetation in coparison with the last moraine: it cannot be excluded that it has been active at least until recent times.