The study of Burano paleo-lagoon—Wetland of International Value, has allowed us to better define and extend the reconstruction of the Holocene paleoenvironmental evolution of the paleo-lagoons previously studied, located on the Tyrrhenian coast in central Italy. The investigated area is located in Southern Tuscany near the Burano Lake. The area was investigated by means of field surveys, historical maps, 16 coring, sedimentological, palynological and microfaunal analyses (foraminifera and ostracods), combined with robust geochronological control provided by 52 datings (14C and OSL). The study allowed us to reconstruct the environmental and morphological evolution of the Burano paleo-lagoon during the last 8000 years and to hypothesize a Rise Sea Level (RSL) curve. In this context, 5 main evolutionary phases have been recognized. (1) before 7.5 ka BP in the southern-eastern part, an open lagoon developed; (2) ~6 ka BP a barrier-lagoon system develops throughout the entire area and the lagoon progressively changed from open to closed one; (3) ~5 ka BP the width of the lagoon increases and a lacustrine facies appears along the entire axis of the coastal basin; (4) ~4 ka BP the lacustrine facies shows a discontinuous distribution respect to the previous phase; (5) during the last 4 ka the lacustrine facies disappear and the lagoon turns into a wetland area.

Geomorphologic, stratigraphic, faunistic, palynological and 14C analyses were carried out in the area of the mouth of the Garigliano River characterized by two strand plains that are referred to the Eutyrrhenian and the Holocene, rimming two depressed zones separated by the Garigliano River channel. This study depicts the palaeoenvironmental evolution over the last 8200 years and the landscape context at the time of Minturnae Roman colony. Between 8200 and 7500 yr BP, a wet zone occurred in the northern zone, whereas in the southern part, a lagoon developed. During the final transgression stage and the beginning of the sea level still stand (7500–5500 yr BP), a freshwater marsh formed in the northern zone, and the width of the southern lagoon decreased. Between 5500 and 3000 yr BP, the coastal barrier changed into a delta cusp, a freshwater marsh also appeared in the southern part and the river wandered between the twin marshes. Because of local uplift, previously unknown in this area, part of the floor of the southern marsh emerged, and after 4000 yr BP, both marshes became coastal ponds with prevailing clastic sedimentation. A progressive increment in anthropic forcing on the land took place after 3000 yr BP. The Marica sanctuary was built (7th century BC), and the Roman colony of Minturnae was developed beginning the 3rd century BC. The shallow depth of the ponds prevented their use as harbours, and saltwork plants can be ruled out based on the faunal and palynological data. The ongoing infilling of both ponds was never completed, and their reclamation is still in progress.

We present a paleoenvironmental reconstruction for the mountain fringe between the South-Eastern Alps and the Northern Dinarides (NE-Italy/W-Slovenia) during the Last Glacial Maximum. We focused on a new sedimentary and paleoecological archive spanning the LGM acme, located in an aggrading, permanently flooded and ponded plain, dammed by an active fluvioglacial megafan. The ecosystem reconstruction, based on two high resolution pollen records, is supported by a rich plant macrofossil flora and constrained by a robust radiocarbon chronology between 26 and 22calka BP. We show evidence for persistence of boreal trees and of different open boreal forest types throughout the LGM at the south-eastern mountain fringe of the Alps and the Northern Dinarides. Fire frequency is responsible for high, oscillating forest openness. The paleobotanical record is discussed in the light of the ecogeographic diversity of the region. A belt formed by Swiss stone pine, larch and dwarf mountain pine on limestone bedrock, and accompanied by Spruce in the floodplain, extended uphill, while proximal outwash plain supported Scots pine and dwarf mountain pine. These differences arise from groundwater regimes rather than from local climate variability. A steep moisture gradient from the semiarid pedoclimatic regime prevailing in the Adriatic alluvial plain to the forested mountain fringe is related to the orographic rainout triggered by southern air circulation. Mesophytic broad-leaved forest trees did not withstand the LGM temperature extremes in zonal ecosystems at the Alpine–Dinaric fringe; however, the fossil evidence suggests a number of microrefugia in karstic and thermal spring habitats of the northern Adriatic.

The C-14 dating of buried soils and peat layers from tufa dammed swampy-lacustrine sequences allows us to outline the aggradation/degradation sequence of Holocene tufa dams in central Italy and northern Ethiopia. In northern Ethiopia, the aggradation of tufa dams started before 9,510 +/- 100 C-14 yr BP (11,080-10,590 yr cal BP), turned to decline around 5,610 +/- 70 C-14 yr BP (6,450-6,305 yr cal BP) with short-lived alternating stages of incision/deposition since ca. 4,710 +/- 70 C-14 yr BP (5,580-5,320 yr cal BP). After ca. 2,380 +/- 50 C-14 yr BP (2,710-2,340 yr cal BP), fluvial incision completely cut the tufa dams. In central Italy, the aggradation of tufa dams started before 9,310 +/- 100 C-14 yr BP (10,211-10,184 yr cal BP) and declined after 6,190 +/- 70 C-14 yr BP (7,240-6,990 yr cal BP). From ca. 4,610 +/- 100 C-14 yr BP (5,600-5,050 yr cal BP), alternating stages of dam erosion/aggradation occurred, eventually followed by a phase of deep incision down to the present valley floors. The occurrence of similar trends of tufa dam aggradation/erosion in Mediterranean Europe and East Africa, as compared with the patterns of Holocene climate in both areas seems to indicate that cold/warm and dry/wet fluctuations have controlled the aggradation/erosion phases of tufa dams including their ultimate incision by streams. On the other hand, the comparable evolution of tufa dams in areas quite different in geographical position points out the significant morphogenetic role of climate changes at the global/supra-regional level.

In the early Holocene a small lake formed by landslide-damming of the Fosso del Lago stream close to Montelago (Sassoferrato, Province of Ancona), a village of the northern Marche sector of the Adriatic side of the Umbria-Marche Apennines (central Italy). A targeted comprehensive and multidisciplinary project, consisting of a geomorphological survey, seismic tomography, and sediment core drilling, was carried out in this area and complemented by radiocarbon dating and pollen analysis. Geomorphological, chronological and paleoenvironmental constraints for the lake formation, evolution and extinction, also accounting for some apparently contradictory information from the Gregorian Cadastre (1816-1835 AD), were thus obtained and are presented and discussed in this work. We propose an evolutionary frame where the damming landslide (Montelago Landslide, MLL) is the reactivation of a larger first time landslide post-dating the upper Pleistocene coldest stages. Large amounts of calcareous breccia boulders incorporated into the MLL runout caused an effective stream blockage and the formation of a small lake. The radiocarbon dating of the lacustrine sediment was useful for roughly constraining the landslide blockage at about the Boreal-Atlantic transition. Both the stream blockage and some secondary landslide movements brought about important changes in the Fosso del Lago catchment. Besides the production of the lacustrine trough, key modifications include a marked convexity of the longitudinal stream profile, an associated epigenetic gorge and distinctive knickpoints on residual landslide boulders. Our study allowed the reconstruction of a preliminary Holocene pollen sequence that, to date, is unique for this sector of the Central Apennines. The pollen record revealed that in the Montelago site, a pre-forest environment with Corylus, Ulmus, Fraxinus and Tilia characterizes the early stages of lake existence and is followed by a beech forest expansion culminating at about 6640-6490 cal. BP with a delayed spread of Abies. Starting from 5910-5750 cal. BP, an increasing human agro-forestry-pastoral activity is recorded in association with beech forest reduction and concomitant expansion of xerofile and herbaceous taxa. The major environmental modifications recorded by the sediment core can be related to climate changes as well as to human activity, displaying both specific behaviours and similarities with already known sites of the Mediterranean area. Although the age of the landslide-dammed lake extinction is not strictly constrained, it is yet ascertained that the water pond represented in the 19th century Gregorian cadastral maps a little further upstream the paleolake site, far from being a relic of the landslide-dammed lake, is rather a small man-made reservoir dug long after the former lake dried up.

The C-14 dating of organic-rich layers from the backfill sequences of the Triponzo village tufa dam (Tiber River basin) allows us to outline the Holocene aggradation/erosion stages of fluvial tufa in Central Italy. Here, the deposition of tufa first occurred prior to 8240 +/- 75 C-14 yr BP (7480-7070 cal bC) and continued, even if with different rates, giving rise to a lacustrine/swampy basin upstream. Since 3760 +/- 60 C-14 yr BP (2350-2010 cal bC) a sequence of alternating periods of dam erosion and aggradation occurred. After 2825 +/- 60 C-14 yr BP (1160-830 cal bC) fluvial incision eventually cut the dam down to the present valley bottom, being only interrupted by a short-lived phase of dam aggradation which caused the formation of a strath terraces covered with gravels and tufa sands. A comparable evolution pattern is shown by other tufa dams in Central Italy. This paper deals with the control factors of tufa deposition/erosion during the Holocene with a particular reference to the role of climate changes.

This paper presents a detailed description of the stratigraphic architecture of the Late Pleistocene/Holocene Tiber delta succession in order to document the passage from wave-dominated estuary to wave-dominated delta in the broader context of Late Quaternary sea level fluctuations. This succession constitutes a sequence-stratigraphic unit known as Tiber Depositional Sequence (TDS), which was deposited during the last glacial-interglacial cycle (last 120 ka). Our study is based on the examination of an enormous amount of data derived from the stratigraphy of about 300 wells, petrographical and paleontological data (foraminifera, ostracoda, pollen, and plant macrofossils), C-14 dating, and from the integration of geomorphological and geoarcheological data. Recently a 100 m deep core (Pesce Luna well) was studied through a multidisciplinary approach and a detailed description of sedimentary fades, foraminifer and ostracod assemblages, pollen and C-14 dating is presented in this paper. The new data allowed to produce three new correlation panels and to describe in more detail, with respect to previous interpretations, the stratigraphic-depositional architecture of the TDS, which internally shows the preservation of sediment deposited during the early and late lowstand, the transgressive and the highstand systems tracts. Alluvial and coastal depositional systems characterize the early lowstand phase of the TDS, which developed during the eustatic sea-level fall between about 120 and 30-26 yr BP. During the late lowstand phase, which is characterized by stillstand and slow eustatic sea-level rise a prograding delta and an aggrading incised-valley fluvial fill developed. The Tiber incised valley was transformed into a wave-dominated estuary during the transgressive phase (TST), whereas a coastal-shelf sedimentation took place during the subsequent highstand phase (HST). This study confirms the lithofacies distribution resulting from transgression and infilling of the wave-dominated estuaries, but also shows how the transition to a wave-dominated delta, prograding at the time of sea-level highstand occurred. Changes in sediment input, climatic variations and, more recently, human activities played a major role in the development of the Tiber delta during the last 20,000 yr BP. In the last 3000 years a relationship between progradational phases of the delta and flood events of the Tiber river has been highlighted, suggesting also the formation and merging of barrier-spits to the mainland. (C) 2013 Elsevier B.V. All rights reserved.

Geomorphologic, stratigraphic, faunistic, palynological and carbon isotope analyses were carried out in the area of the Tiber river mouth. The results depict a complex palaeoenvironmental evolution in the area of the Roman town of Ostia, ascertain the changes of the Tiber river delta over the last 6000 years and support a re-interpretation of some archaeologic issues. The wave-dominated Tiber delta evolved through three distinct phases. In the first step (5000-2700 yr BP) a delta cusp was built at the river mouth, which was located north of the present outlet. Subsequently (2700-1900 BP), an abrupt southward migration of the river mouth determined the abandonment of the previous cusp and the progradation of a new one. The third step, which is still in progress, is marked by the appearance of a complex cusp made up of two distributary channels. The transition from the first to the second evolution phase occurred in the seventh century BC and was contemporary to the foundation of Ostia, as suggested by historical accounts. However, the oldest archaeological evidence of the town of Ostia dates to the fourth century bc, when human activity is clearly recorded also by pollen data. We suggest that the first human settlement (seventh century bc) consisted of ephemeral military posts, with the aim of controlling the strategic river mouth and establishing the Ostia saltworks. Only after the fourth century bc the coastal environment was stable enough for the foundation and development of the town of Ostia.

Records from floodplain deposits in selected river valleys of the Dnieper River basin, Belarus, were studied to reconstruct the phases of natural and anthropogenic environmental changes in the Holocene. Sediment archives in the main valley and its four tributaries of different orders were studied by means of lithological and geochemical methods (including grain-size analysis, X-ray fluorescence analysis, spectral analysis), spore-and-pollen analyses, and radiocarbon dating. Some differences in the response of different-order fluvial systems to climate changes and human impact have been revealed. Fluvial deposits in the Dnieper valley and in first-order valleys contain records on the regional-scale natural environmental changes, while human impact is clearly pronounced only in deposits of the last millenium. Fluvial deposits in the valleys of second-order record river evolution only since the Neoholocene. At the same time, the lacustrine or carbonate freshwater deposits in these valleys contain the records of environmental changes in the entire Holocene. Changes in the sequence and composition of fluvial deposits due to human impact occurred in high-order valleys almost 2000 years later (since ∼500 years BP), as compared with pollen data.

In the Early Holocene, the central Marches (Italy) underwent a widespread development of forest cover and soils which drastically reduced slope degradation and related aggradation processes in riverbeds. In such conditions, streams deeply incised the previous alluvial sediments. In the Apennine sectors, linear erosion was locally prevented by the growth of travertine dams in correspondence with river channel knickpoints and waterfalls. Fluvial deposition prevailed in the peri-Adriatic hilly belt, where river valleys still extended from the present coastline to the uprising Adriatic Sea, as testified by a 50-m-deep cored log, drilled near the Potenza River mouth. Several archaeological sites, ranging from the Mesolithic to the Aeneolithic, testify the recurrent presence of small-scale human groups on the alluvial plains of the lower valley sectors. Sandy-clayey sediments, emplaced by flooding episodes, repeatedly buried these settlements which were commonly located on the riversides. Small Aeneolithic communities were also present in the mountain sectors, around travertine-dammed swampy-lacustrine basins. On top of the sequences, Bronze Age sites were locally found. Widespread deforestation started in the early Iron Age (about 3000 yr BP), when alluvial plains and terraces were permanently occupied by large-scale human settlements. Geo-archaeological evidence of systematic deforestation at 2950 ± 50 14C yr BP, consisting of numerous round-shaped 1.5-3 m wide hollows, filled with soil sediments and upturned blocks of alluvial gravels, were found on top of a fluvial terrace in the Esino River basin. From the Iron Age to recent historical times, notwithstanding the progressive increase of debris supply to the drainage systems due to the spreading agricultural-pastoral activities, erosion dominated almost everywhere in the Marches rivers, likely induced by climatic factors.

The glacial history of the Tagliamento morainic amphitheater (southeastern Alpine foreland, Italy) during the last glacial maximum (LGM) has been reconstructed by means of a geological survey and drillings, radiocarbon dating and pollen analysis in the amphitheater and in the sandur. Two phases of glacial culmination, separated by a distinct recession, are responsible for glacial landforms and related sediments in the outer part of the amphitheater. The age of the younger advance fits the chronology of the culmination of the last glaciation in the Alps, well established between 24 and 21 cal ka BP (20 to 17.5 C-14 ka BP), whereas the first pulse between 26.5 and 23 cal ka BP (22 to 21 (14C) ka BP), previously undated, was usually related to older (pre-LGM) glaciations by previous authors. Here, the first pulse is the most extensive LGM culmination, but is often buried by the subsequent pulse. The onset and final recession of the late Wurm Alpine glaciation in the Tagliamento amphitheater are synchronous with the established global glacial maximum between 30 and 19 cal ka BP. The two-fold LGM glacial oscillation is interpreted as a millennial-scale modulation within the late Warm glaciation, caused by oscillations in inputs of southerly atmospheric airflows related to Dansgaard-Oeschger cycles. Phases of enhanced southerly circulation promoted increased rainfall and ice accumulation in the southern Alps. (c) 2007 University of Washington. All rights reserved.

New data from 45 sediment cores, 35 C-14 datings and numerous pollen analyses were considered for improving the understanding of the stratigraphy of the Tiber River delta plain. Bottom to top, the three recognized units pointed to the following environments: i) continental shelf with fairly noticeable siliciclastic input, ii) coastal plain with spread lagoons and sandy-gravelly beaches and, iii) a capping complex and mostly a paralic sediment suite which records the landscape evolution over the last 18 kyr. The study area, fully emerged until 13 kyr BP, is characterized by the deep and narrow valley incised by the Tiber River during the last glacial sea level low stand. Following its origin the valley underwent partial submersion by sea-water while Tiber River was building up a seaward retrograding bay-head delta. Beginning from 8 kyr BP this feature progradated and at 6 kyr BP changed into a wave-dominated delta which originated a strand plain with two coastal lakes. In Roman times, the most important harbour of the antiquity was built close to the Tiber River mouth. During the Renaissance, an enhanced progradation phase shaped a landscape akin to the present one, apart from some minor changes subsequent to the reclamation of coastal ponds and relic marshes in modern times. The results herein discussed confirm that the post-glacial sea level rise and the Tiber River solid discharge were the two antithetic mechanisms responsible for the landscape evolution of the deltaic area. However, during the last transgression even the antecedent topographhy played an important role, and since Neolithic times the effects of the anthropogenic impact were also noticeable.

Kalicki T. (et.al.), River response to the Holocene climatic fluctuations: a case study from Zelvianka river valley (Belorussia). (IT ISSN 0394-3356, 2004). A multidisciplinary research aimed at depicting the evolution of Zelvianka river valley (NW Belorussia) during the Holocene has been carried out. The valley incision started at the local ice-sheet terminus in the Young Pleniglacial following the Pomerian stage of the last glaciation (some 16÷15 ka BP) and, as marked by important changes of the river regime, was virtually over at c. 13.8 ka BP (Middle Lithuanian stage of deglaciation). Detailed geomorphologic survey coupled with stratigraphic analysis, C dating and pollen spectra provided sound evidence that the complex structure of the valley bottom resulted from the lateral migration of the river which in turn depended upon large-scale climatic changes. Besides of critically reviewing the literature data new, C dated pollen chronostratigraphies, fairly consistent with the up to date regional palynologic framework were obtained. Actually it has been found that the most important channel and sedimentation changes cluster at the AL/YD transition, c. 9300 BP, BO/AT transition, middle Atlantic, c. 4200 BP, c. 3250-3000 BP, Roman time (2100 BP) and 1000-900 BP, thus matching the timing of humid and cool climatic phases recorded by the enhanced activity of Belorussian and central European rivers. Though the first prehistoric settlements over the study area date back to Late Neolithic, Zelvianka valley was virtually unaffected by the human impact, except from some low intensity, local aeolian processes which developed in the Subboreal and Subatlantic on the deforested spots RIASSUNTO: Kalicki T. (et.al.), Effetti delle fluttuazioni climatiche oloceniche sull’evoluzione della valle del fiume Zelvianka (N-W Bielorussia). (IT ISSN 0394-3356, 2004). E’ stata effettuata una ricerca multidisciplinare finalizzata alla ricostruzione dei tratti evolutivi più salienti della valle del fiume Zalvianka (Bielorussia nord occidentale) durante l’Olocene. L’incisione di questa valle, iniziatasi nel Pleniglaciale al termine dello stadio Pomeriano dell’ultima glaciazione (ca. 16÷15 ka BP) e conclusasi a ca. 13,8 ka BP (media deglaciazione Lituana), ha registrato importanti cambiamenti del regime fluviale. I dati geomorfologici, stratigrafici, palinologici unitamente a quelli della cronologia radiocarbonio concordano nell’indicare che la complessa struttura del fondo della valle deriva dalle migrazioni laterali del fiume che, a loro volta riflettono variaizioni climatiche di portata almeno regionale. Lo studio ha evidenziato che le maggiori variazioni tanto nel regime di sedimentazione che nella direzione del corso fluviale si sono verificate alla transizione Alleröd/Dryas III, a ca, 9300 BP, alla transizione Boreale/Atlantico inferiore, nel medio Atlantico, a ca. 4200 BP, a ca. 3250÷3000 BP, in epoca Romana (2100 BP) ed infine dal 1000 al 900 BP. La datazione di tali eventi ne rivela la contemporaneità con fasi climatiche umide e fredde di portata almeno regionale in quanto precedentemente riportate per molte valli fluviali della Bielorussia e dell’Europa centrale. Nonostante la presenza di insediamenti umani nell’area di studio a partire dall’ultimo Neolitico, la valle del fiume Zelvianka non mostra significative evidenze di impatto antropico, eccezion fatta per modesti processi eolici attivi nel Pre-boreale e nell’Atlantico inferiore nelle modeste aree soggette a deforestazione da parte dell’uomo.

We present a quantum Monte Carlo study of the solvation and spectroscopic properties of the Mg-doped helium clusters MgHe(n) with n=2-50. Three high-level [MP4, CCSD(T), and CCSDT] MgHe interaction potentials have been used to study the sensitivity of the dopant location on the shape of the pair interaction. Despite the similar MgHe well depth, the pair distribution functions obtained in the diffusion Monte Carlo simulations markedly differ for the three pair potentials, therefore indicating different solubility properties for Mg in He(n). Moreover, we found interesting size effects for the behavior of the Mg impurity. As a sensitive probe of the solvation properties, the Mg excitation spectra have been simulated for various cluster sizes and compared with the available experimental results. The interaction between the excited 1P Mg atom and the He moiety has been approximated using the diatomics-in-molecules method and the two excited 1pi and 1sigma MgHe potentials. The shape of the simulated MgHe50 spectra shows a substantial dependency on the location of the Mg impurity, and hence on the MgHe pair interaction employed. To unravel the dependency of the solvation behavior on the shape of the computed potentials, exact density-functional theory has been adapted to the case of doped He(n) and various energy distributions have been computed. The results indicate the shape of the repulsive part of the MgHe potential as an important cause of the different behaviors.

We determined two potential energy surfaces (PES) for the He-CH4 system by means of MP4 and Valence Bond (VB) calculations. The MP4 potential is similar to the one commonly adopted for this system [U. Buck, K. H. Kohl, A. Kolhase, M. Faubel, and U. Staemmler, Mol. Phys. 55, 1255 (1985)], while the VB PES is slightly more attractive. To evaluate the reliability of these potentials, we investigated the scattering properties by performing close coupling calculations, and concluded that: (i) the available experimental data do not permit the ranking among the PES considered; (ii) some theoretical predictions differ considerably from the experimental data, and these discrepancies cannot entirely be ascribed to the inaccuracy of the ab initio calculations; (iii) the scattering properties at low energy might discriminate between the MP4 and VB potentials.