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We reconstructed vegetation, fire and watershed history during the Late Roman-Early Middle Ages and in the last three centuries in a mixed conifer forest forming the middle mountain elevational belt in the inner Alpine region, analyzing co-registered micro-botanical data, charcoal particles, sediment lithology, nutrients, and modern pollen deposition from a high-resolution peat record in Valmalenco (Italian Alps). During Late Roman Age the site hosted a dump mixed conifer forest dominated by Picea abies and Abies alba on peaty forest soil, locally affected by fires which also triggered episodes of hillslope denudation. Fire frequency increases during Early Middle Ages dry and warm phases, favoring Alnus viridis and Larix, while Abies alba and Alnus glutinosa type maintained a main role in the pre- and post-fire. Specifically, Abies alba, nowadays eradicated from the Valmalenco watershed, withstood the local regime of low intensity surface fires for more than a millennium, from the Late Roman throughout the Early Middle Ages. Larix, Alnus viridis and Fraxinus excelsior abundance in modern vegetation is ascribed to effects of intensified disturbance in the Early Modern Age, and to further woodland thickening triggered by fire suppression and abandonment after the Second World War.

Pollen data are widely used as proxies to reconstruct past vegetation and climate changes. During the last decades numerical techniques have been developed to quantitatively estimate climate parameters from fossil pollen assemblages. This contribution introduces first the concepts and methodologies based on modern calibration sets to obtain past climate reconstructions. Then, focusing on high-elevation environments, the use of elevational transects as a tool for the evaluation of pollen-climate models and a temperature reconstruction obtained from an alpine fossil site are presented.

Large portions of the highly populated central Po Plain in northern Italy are susceptible to major liquefaction–induced ground failure and resulting damage, as illustrated by the 2012 Mw 5.6–5.8 earthquake sequence. Our work presents a comprehensive geomorphological, stratigraphic and geotechnical dataset from a 1012 km2 study area in the alluvial plain, analysed through the integration of different methodologies. For hazard reduction planning, we qualitatively and quantitatively assess liquefaction potential by the identification of three discrete geomorphological domains. Each geomorphological domain has variable Late Pleistocene to Holocene geological evolution, geotechnical characteristics and thus liquefaction susceptibility, as deduced from interpretation of three 25–m deep continuous cores and calculation of liquefaction potential based on the geotechnical analysis of 239 cone penetration tests (CPTs). For land use planning, we present this information at various map scales consistent with inherent uncertainties of data availability. The investigation procedures and geological–geotechnical interpretations may be applicable to similar liquefaction–prone areas elsewhere.

Cores and trenches drilled or dug in religious and secular buildings in the hilltop town of Bergamo (northern Italy) were investigated by means of micro/macrobotanical and pedochemical analysis to unravel the cultural vegetation history of the area during ca. seven centuries across the Bronze—Iron Ages. We explore the predictive power of biological proxies, nutrients, and coupled 14C datings to reveal early phases of human settlement and activity in a modern urban context with low visibility and difficult accessibility. Our records suggest that a farming centre was active on the Bergamo hilltop as early as the 15th century bc. Crop and animal husbandry reached a high point between the 11th-8th century bc. Plant and biogeochemical proxies predict extensive and diversified cereal cropping, flax and grapevine cultivation, as well as herd stalling at a watering pond, free range livestock growing in woodlands, and pastoralism, shown by hay making and overgrazing evidence. The suggestive hypothesis of carding wool is mentioned but is currently untenable. Furthermore, we identified a possible phase of abandonment starting from the 8th century bc, to be further investigated, and in agreement with archaeological data suggesting settlement decline in the 8th-6th century bc. Our research highlights the dedication to pastoralism of the Bergamo hill since prehistoric times. The settlement position was strategic for pastoralists to exploit biological and water resources in space, season and elevation, i.e. from the plain to higher Alpine pastures. Ethnographic examples and Middle Age written sources strongly support this picture.

During the Last Glacial Maximum (LGM, 30 to 16.5 ka ago), the Great Adriatic-Po Region (GAPR) was deeply affected by the spread of glaciers from the Alps to the southern foreland and by the dropping of the sea level to ~ -120 m amsl. The combination of these two events triggered the aggradation of the Great Po Plain (GPP), a vast flat area between the Alpine chain, the Italian Peninsula and the north-western Balkan Peninsula, physically and ecologically featured through a range of palaeogeographic and palaeoecological conditions. The low-elevated Prealpine sectors and the Alpine foothills supported more extensive forest stands, due to increased orographic rainfall. These were open boreal forests which persisted throughout the LGM, while open woodlands, steppes, semideserts and wetlands occupied the lowlands. A complex ecogradient, including both an Alpine and a continental timberline, is documented by the fossil records at the NE Alpine border, with a larch-pine forest-steppe belt, in contact with steppes and loess areas extending in the plain, on the dry extreme of the gradient. Still, edaphic wetlands occupied the waterlogged silty soils in the lowlands. Other areas, marked by active geodynamic processes, supported semideserts, i.e. grooves of xerophytic herbs and shrubs. Enhanced aridity and the development of deflation areas, prompted the accretion of loess cover at the northern and southern margins of the GPP. Fauna recorded the gradual disappearance of mammoth, woolly rhino and giant deer, together with cave bear. Gravettian and Epigravettian hunter-gatherer groups inhabited the GPP, although their presence and settlement dynamics at the margins and across this region has long been questioned. As a matter of fact, a handful of archaeological sites composes a patchy record of the peopling of the plain itself. At the northern rim of the GAPR, characterized by a well-developed karst region, several caves and rock shelters record the presence of hunters of bisons

The hilltop town of Bergamo, at the southern fringe of the Italian Alps, represents a typical example of the stepped emergence of a prehistoric settlement developing into a proto-historic urban center in the Iron Age. We present here unprecedented multidisciplinary evidence based on several near-site stratigraphies, supported by a robust radiocarbon chronology and by a continuous fine-resolution sedimentary and paleoecological record from a pond used for livestock watering, which was intercepted by drilling underneath the modern Catholic Cathedral. The obtained chronostratigraphy documents the development of arable and fallow land including cereals, legumes and livestock husbandry starting as early as 3355 yrs. cal BP (median of modeled calibrated ages, i.e., 15th century BC). This evidence indicates that already in the Middle Bronze Age the very center of the hilltop of the Bergamo Hill supported an early farming center. Land use reached an acme between 2980 and 2753 yrs. cal BP, triggering intense soil erosion by runoff processes. Paleobotanical evidence suggests uphill grapevine cultivation at the southern Alpine fringe at 2900 yrs. cal BP. Data support settlement continuity until around 2700 yrs. cal BP (8th century BC), before the growth of the Celtic town in the 6th–5th century BC. The location and development of the farming center yet in the Bronze Age might have been promoted by topographical diversification, high geomorphic weathering rate, soil suitability for agriculture and pastoralism, and water availability on the northern side of the hill, secured by orographic precipitation in warmer seasons.

The Eurasian (née European) Modern Pollen Database (EMPD) was established in 2013 to provide a public database of high-quality modern pollen surface samples to help support studies of past climate, land cover, and land use using fossil pollen. The EMPD is part of, and complementary to, the European Pollen Database (EPD) which contains data on fossil pollen found in Late Quaternary sedimentary archives throughout the Eurasian region. The EPD is in turn part of the rapidly growing Neotoma database, which is now the primary home for global palaeoecological data. This paper describes version 2 of the EMPD in which the number of samples held in the database has been increased by 60 % from 4826 to 8134. Much of the improvement in data coverage has come from northern Asia, and the database has consequently been renamed the Eurasian Modern Pollen Database to reflect this geographical enlargement. The EMPD can be viewed online using a dedicated map-based viewer at https://empd2.github.io and downloaded in a variety of file formats at https://doi.pangaea.de/10.1594/PANGAEA.909130 (Chevalier et al., 2019).

In this paper, we describe a 5500-year long core obtained from a lake in the Prealps of northern Italy to investigate the impact of human communities on the lacustrine environment. Specifically, we report micro-botanical proxies (upland and aquatic pollen, algae, cyanobacteria, dung spores, microcharcoal particles), sedimentary parameters (LOI steps, calcimetry, FTIR spectra) and nutrients (P forms, C/N and K) on paired samples in a high-resolution stratigraphy, dated by 14C AMS dating and tie point correlation. Independent archaeological evidence indicates the existence of lakeside settlements and farming in Bronze Age times from c. 4000 to 3300 cal yrs. BP. The impact of this Bronze Age village is recorded by an accumulation of plant detritus, pollen, charcoal and abundant wood and bone-derived ash. Intensive P mineralization by ash production was accompanied by the rapid burial of Pinorg, K, and microcharcoal. Correlated peaks of Porg and pasture plant pollen mark the contribution of animal husbandry to Porg lake sink. The nutrient flux produced by external catchment cropping contrasts with the internal flux discharged by prehistoric dwelling and in turn distinguishes domestic hearth production from a contribution by animal husbandry. Forest conditions and lake sedimentation returned to semi-natural baseline at the end of this 700-year long phase of Early to Middle Bronze Age settlement, but pollen proxies indicate that lake-side forests did not fully recover. Lake Lucone represents a key site, since it documents interactions between bronze Age settlements and related ecological impacts on both terrestrial environment and lacustrine sedimentation, as recorded in a continuous sequence, as well as the end of Bronze Age pile dwelling culture.

During the last glaciation the Eurasian continent was impacted by the global reorganization of atmospheric circulation caused by North Atlantic events, through changes in moisture storm tracks modulated by orography. Our research explores the linkages between climate evolution in the North Atlantic and in the Alps between 30.6 and 12.5 ka, This period, centered on the Last Glacial Maximum, experienced the most recent phase of maximum global ice volume, corresponding to a millennia-long phase of sea-level lowstand, minima in reconstructed sea surface temperatures and isotopic values from polar ice. We present a high-resolution multiproxy record from Lake Fimon at the southern Alpine foothills, where a larch forest-steppe persisted throughout the coldest spells. We analyse the fine climate structure of the MIS 3–2 transition, of the Alpine Last Glacial Maximum stepped by HS2, and provide an unprecedented fine resolution and accurate 14C dating of the Last Glacial Maximum and the early Alpine Lateglacial. We reconstructed quantitative climate parameters based on sensitive pollen descriptors, and derived co-registered sedimentary proxies for dust flux. Reconstructed series suggest that extreme continental spells in the Alps and cold boreal winters match the timing of Heinrich Stadials 2 and 1, episodes of iceberg discharge and release of rock fragments (Ice Rafted Debris) in the North Atlantic. The initiation of the LGM at 27.3 ka is marked by a 4 °C drop in July temperatures, likely responsible for the onset of glacial build-up in the Southern Alpine piedmont. The first extreme continental spell coincides with the British-Irish-sourced IRD event at 26.2 ka and with glacier retreat in the Southern Alps, persisting in the subsequent HS2. Late Glacial glacier collapse and extreme drought occurred during the first half of the HS1, 17.4–16.2 ka. The comparison of the results obtained at Lake Fimon with other terrestrial Eurasian records and with recalibrated marine chronolo

Understanding the recent events marking the late Quaternary history of the Po Plain (N-Italy) is of overriding importance to decipher the record of depositional versus erosional phases, and their interplay with climatic, tectonic, and human forcing. We reconstructed the structural setting and chronostratigraphy of a Holocene succession crosscut by a thrust fault located south of Montodine (Cremona, Italy) within the Po Plain. The fault shows a maximum displacement up to one meter. Radiocarbon dating fixes a minimum age of 11.9 cal ka BP for the postglacial river entrenchment and constrains the fault movement age between 5.9 and 3.4 cal ka BP. Undeformed Late Medieval coarse gravels cover the faulted succession. Due to the outcrop position, lying above the buried frontal thrusts of the Southern Alps and North Apennines, we propose that faulting results from secondary surface effects induced by seismic shaking. We discuss two main mechanisms, both related to lateral spreading, that can result in the formation of reverse faults close to the surface. The Soncino area, recording one of the strongest historical earthquakes of the central Po Plain (1802), is considered as a possible source for seismic shaking. The results of this study are a contribution for the assessment of the potential seismic hazard in one of the most populated regions of Europe.

Montane vegetation is traditionally known to be particularly sensitive to climate changes. The strong elevational climatic gradient that characterizes mountain areas results in a steep ecological slope, with several ecotones occurring in a small area. Modern pollen deposition is significantly predicted by both vegetation cover and pollen production; in turn, each predictor is significantly predicted by elevation and climate. Analyses of modern pollen deposition are essential to calibrate fossil pollen sequences accounting for site topography and depositional process, and thus for pollen-based palaeoenvironment and palaeoclimate reconstructions. This study analyzes the relationships among modern pollen assemblages, vegetation and climate along an elevational gradient in the outer belt of the European Alps. Results of Canonical Correspondence Analysis (CCA) demonstrated a general good agreement with previous studies, which identified elevation as the main gradient in the variation of modern pollen and vegetation assemblages in elevational transects. Modern pollen assemblages have been studied in pollen traps and moss samples from different vegetation communities along an elevational transect (stretching from 1240 to 2390 m asl), as well as the vegetation using the Braun-Blanquet system up to the 10 m radius scale, field vegetation surveys and aerial photographs for plant cover of the main species for larger surfaces. Moss samples are assumed to record an average of several years of pollen deposition and can be profitably used as analogues for fossil pollen assemblages; while pollen traps can be expressed as Pollen Accumulation Rates (PAR) and used as a modern reference to estimate past plant population densities. Alnus viridis, the main woody species forming dwarf forests in the oceanic-type timberline ecotone, shows a specific elevational PAR arrangement under modern climate conditions. Strong pollen producers (e.g. Pinus sylvestris/mugo, Picea, Castanea, Corylus and

AIM: Long‐term ecological data provide a stepped frame of island ecosystem transformation after successive waves of human colonization, essential to determine conservation and management baselines. However, the timing and ecological impact of initial human settlement on many islands is still poorly known. Here, we report analyses from a 4800‐year sedimentary sequence from Gran Canaria (Canary Islands), with the goal of disentangling forest responses to natural fire from early human pressure on the island. LOCATION: La Calderilla, a volcanic maar caldera at 1,770 m a.s.l. on Gran Canaria. TAXON: Plants and fungi. METHODS: A core from the caldera infill was analysed for sediment properties, pollen, micro‐ and macrocharcoal, with radiocarbon and biochronology dating. Fossil data were statistically zoned and interpreted with the help of cross‐correlation and ordination analyses. Surface samples and a pollen–vegetation training set were used as modern analogues for vegetation reconstruction. RESULTS: Before human settlement (4,800–2,000 cal. yr bp), pine (Pinus canariensis) pollen dominated. Extensive dry pine forests characterized the highlands, although with temporary declining phases, followed by prompt (sub‐centennial scale) recovery. Towards 2,280 cal. yr bp there was a shift to open vegetation, marked by an increase in coprophilous spores. Coincidental with independent evidence of human settlement in the pine belt (2,000–470 cal. yr bp) there was a decline of pine and a peak in charcoal. Following historic settlement (470–0 cal. yr bp), pollen producers from anthropogenic habitats, secondary vegetation and coprophilous fungi increased in abundance, reflecting higher pressure of animal husbandry and farming. Modern moss polsters reflect extensive reforestation since 1950 ce (Common Era). MAIN CONCLUSIONS: From 4,800 cal. yr bp, the pristine vegetation covering the Gran Canaria highlands was a mosaic of dry pine forests and open vegetation. The pine forests sustained

The BRAIN (Botanical Records of Archaeobotany Italian Network) database and network was developed by the cooperation of archaeobotanists working on Italian archaeological sites. Examples of recent research including pollen or other plant remains in analytical and synthetic papers are reported as an exemplar reference list. This paper retraces the main steps of the creation of BRAIN, from the scientific need for the first research cooperation to the website which has a free online access since 2015.

We evaluated pollen-climate models developed for past temperature reconstruction in northern Italy by comparing polleninferred temperature series with site-specific instrumental series in two records covering the last 200 years and provided with a pollen sample resolution of 5/9 years. Moderate to good correlation is found. We discuss the methodological approach and the possible influence of human activities in the pollen-inferred reconstructions.

The Last Glaciation environmental history of the Po Plain (Northern Italy) is still poorly known. Here we present a multiproxy record from a compressed peat dated 33-30 ka cal BP, underlying the Last Glacial Maximum fluvio-glacial belt in the Adda River catchment. Slow river dynamics and subsurface water saturation granted stable surfaces supporting mixed pine-birch forests, including open wetlands - marshes and swamps - and open drylands, with juniper bushes, connected to sandy river bars. Fire phases favoured birch but decreased arboreal pollen, although open lands did not expand. We discuss relationships with millennial climate variability between GI-6 and GS-5.1.

Dynamics and control of processes over social networks, such as the evolution of opinions, social influence and interpersonal appraisals, diffusion of information and misinfor-mation, emergence and dissociation of communities, are now attracting significant attention from the broad research community that works on systems, control, identification and learning. To provide an introduction to this rapidly developing area, a Tutorial Session was included into the program of IFAC World Congress 2020. This paper provides a brief summary of the three tutorial lectures, covering the most "mature"directions in analysis of social networks and dynamics over them: 1) formation of opinions under social influence; 2) identification and learning for analysis of a network's structure; 3) dynamics of interpersonal appraisals.