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Smaller glaciers (<0.5 km2) react quickly to environmental changes and typically show a large scatter in their individual response. Accounting for these ice bodies is essential for assessing regional glacier change, given their high number and contribution to the total loss of glacier area in mountain regions. However, studying small glaciers using traditional techniques may be difficult or not feasible, and assessing their current activity and dynamics may be problematic. In this paper, we present an integrated approach for characterizing the current behaviour of a small, avalanche-fed glacier at low altitude in the Italian Alps, combining geomorphological, geophysical and high-resolution geodetic surveying with a terrestrial laser scanner. The glacier is still active and shows a detectable mass transfer from the accumulation area to the lower ablation area, which is covered by a thick debris mantle. The glacier owes its existence to the local topo-climatic conditions, ensured by high rock walls which enhance accumulation by delivering avalanche snow and reduce ablation by providing topographic shading and regulating the debris budget of the glacier catchment. In the last several years the glacier has displayed peculiar behaviour compared with most glaciers of the European Alps, being close to equilibrium conditions in spite of warm ablation seasons. Proportionally small relative changes have also occurred since the Little Ice Age maximum. Compared with the majority of other Alpine glaciers, we infer for this glacier a lower sensitivity to air temperature and a higher sensitivity to precipitation, associated with important feedback from increasing debris cover during unfavourable periods. [ABSTRACT FROM AUTHOR]

• Context: The altitude of timberlines in the central Apennines has lowered over the past few thousand years due to interacting natural and anthropogenic disturbances. These timberlines are usually sharp and consist of coppiced beech forests. • Aims: We found scattered individuals of European black pine ( Pinus nigra Arn.) at two high elevation sites above the timberline on limestone slopes. We investigated the spatial and temporal pattern expansion of black pine and assessed vigour and growth dynamics of pine trees. • Methods: Over 250 individuals were mapped in the two sites using GPS. Several site and tree parameters were measured. Tree-ring widths and the frequency of intra-annual density fluctuations were also recorded. • Results: Black pine expansion started around 30 years ago. Pine trees are randomly distributed at higher elevations with no visible spatial pattern. Germination peaks were synchronous in the two sites, and tree growth displayed very similar chronologies, with synchronous occurrence of intra-annual density fluctuations. • Conclusion: We hypothesise that the reduced livestock grazing over the last decades as well as climate warming are the major driving forces behind the high-altitude expansion of black pine on the central Apennines, where this species was present in pre-historic times. [ABSTRACT FROM AUTHOR]

A core retrieved from Lake Frassino (northern Italy) provided evidence of palaeohydrological change in this area during the last 14 ka. Lithological, malacological and, in particular, stable isotope composition of freshwater shells allowed the delineation of the main phases of lake evolution between the Lateglacial and Holocene. Lateglacial conditions were drier than the Holocene, although a wetter period was inferred before c. 14 ka. According to the oxygen isotope composition of freshwater shells, the Holocene showed a clear bipartition. The first part, which lasted from ∼ 9100 to 7000 yr BP, was drier and was followed by a rapid increase in humidity at ∼ 7000–6800 yr BP. Between ∼ 6800 and 5000 yr BP, there were wetter and more stable conditions, as indicated by smaller δ18O oscillations of Pisidium and Valvata shells. From c. 5000 to 2600 yr BP the record is characterized by larger fluctuations, which may indicate that short-term and particularly pronounced alternation of wet and dry periods occurred. [ABSTRACT FROM AUTHOR]

Records of geomagnetic secular variation have been obtained from three cores recovered from the Salerno Gulf (southern Italy). High-resolution petrophysical and palaeomagnetic measurements enabled the reconstruction of a composite curve of geomagnetic palaeosecular variation (PSV), which is compared with the reconstructed PSV curve from Britain and with the French archaeomagnetic data of the last 2.1ka. The good agreement of the Salerno Gulf record with the above data confirms that our PSV record reaches back for some 9.0ka. In addition to a thick pumice layer originated during the Somma-Vesuvius eruption at AD 79, two other tephra layers were recognized, at about 1.3 and 3.0ka BP, that are probably also of Vesuvian origin. The comparison provides an initial chronological framework for assessing the increasing trend of sedimentation rate and its significant changes at about 2.7ka and 7.0ka BP. This variation in the deposition rate suggests a link with climatic changes recognized in the Mediterranean region. [ABSTRACT FROM AUTHOR]

Lacustrine sediments from Lago di Pergusa in central Sicily provide a Postglacial record of environmental change in the Mediterranean. Magnetic susceptibility measurements, lithofacies characterization and pollen analysis were carried out and integrated to obtain a better reconstruction of the past 11000 years. The chronology is provided by AMS radiocarbon dates on macrofossils or bulk sediment, and by a tephra correlative with a late-Holocene explosion from the Etna volcano. The transition period related to the present interglacial reafforestation, characterized by increasing humidity, started about 10700 years BP. The onset of the wettest conditions of the Postglacial occurred at about 9000 years BP and lasted until about 7200 years BP. Then a trend towards aridification began, leading to very dry conditions at about 3000 years BP. An unquestionable human impact on vegetation is found from 2800 years BP, although earlier land use cannot be excluded. As the climate had already induced change in the vegetation, the well-known human occupancy during the last three millennia did not produce strong effects on the environment. [ABSTRACT FROM AUTHOR]

The Ionian coast of the Basilicata region, southern Italy, is characterized by a remarkable archaeological heritage, valuable crops, and national and international tourism, contributing significantly to the regional economy. In the last two decades, the area has been affected by the heavy recurrence of flooding events, which caused significant damage to agriculture, tourist infrastructure, and archaeological heritage. Both qualitative and quantitative analyses of pluviometric, hydrometric, and erosion/deposition dynamics of main rivers have been carried out in order to investigate the role played by natural factors, climate changes, and human activity. The results show that flooding events in the Metaponto plain were certainly caused by extreme rainy events, but man has also played an important role. The Metaponto plain has been involved in a reclamation consisting of the building of an extensive channel network, which provided better land cultivation, easy access to the beaches, and archaeological heritage protection. The human impact related to the absence of channel cleaning has proved to be the most relevant factor that greatly amplified the effects of low-intensity rainfall events, thus triggering flooding events. [ABSTRACT FROM AUTHOR]