Papers by Donatella Magri
Geogr. Fis. Dinam. Quat, 2019
A review of the climatic variability over the last two millennia based on oxygen stable isotopic ... more A review of the climatic variability over the last two millennia based on oxygen stable isotopic (d18OG. ruber) signals from different areas of the Mediterranean Basin (Minorca Basin, central and south Tyrrhenian Sea,
Taranto Gulf, south Adriatic Sea and Israel) has been proposed. The correlation of data testifies an almost synchronicity of the identified climate events, suggesting an homogeneous response of the marine system to climate oscillations. This overall picture documents that the collapse of the Western Roman Empire results chronologically related to cold event
Roman III solar minimum and that the Roman IV solar minimum (Dark
Age), marks the transition vs a long term cooling trend, spanning ca.
1100 years, that culminates during the Maunder solar minimum (LIA).
In addition, during the Maunder cold event, the strong increase in abundance of planktonic foraminifer Globlorotalia truncatulinoides, suggest the establishment of vertical mixing during the winter season induced by strong winds linked to an atmospheric blocking event.
Climate of the Past, 2019
The Mediterranean region and the Levant have returned some of the clearest evidence of a climatic... more The Mediterranean region and the Levant have returned some of the clearest evidence of a climatically dry period occurring around 4200 years ago. However, some regional evidence is controversial and contradictory, and issues remain regarding timing, progression, and regional ar-ticulation of this event. In this paper, we review the evidence from selected proxies (sea-surface temperature, precipitation , and temperature reconstructed from pollen, δ 18 O on speleothems, and δ 18 O on lacustrine carbonate) over the Mediterranean Basin to infer possible regional climate patterns during the interval between 4.3 and 3.8 ka. The values and limitations of these proxies are discussed, and their potential for furnishing information on seasonality is also explored. Despite the chronological uncertainties, which are the main limitations for disentangling details of the climatic conditions , the data suggest that winter over the Mediterranean involved drier conditions, in addition to already dry summers. However, some exceptions to this prevail-where wetter conditions seem to have persisted-suggesting regional heterogeneity in climate patterns. Temperature data, even if sparse, also suggest a cooling anomaly, even if this is not uniform. The most common paradigm to interpret the precipitation regime in the Mediterranean-a North Atlantic Oscillation-like pattern-is not completely satisfactory to interpret the selected data.
Quaternary Science Reviews, 2018
Climatic and environmental changes of the Middle Pleistocene in Europe provide the context for an... more Climatic and environmental changes of the Middle Pleistocene in Europe provide the context for an important phase in the evolution and dispersal of early hominins. Pollen records from terrestrial and marine sediment sequences reveal patterns not usually visible in palaeoenvironmental reconstructions from archaeological sites alone and show that hominin evolution took place against a background of marked environmental change as forests expanded and contracted in concert with global and regional climatic shifts. It is rare to find archaeological material in stratigraphically long and continuous palae-oenvironmental sequences, yet this is what is needed to enable particular phases of hominin evolution to be securely associated with climatic and environmental changes. At the well-known Middle Pleistocene archaeological site of Ceprano in Italy we have been able to produce a pollen record from the sedi-mentary unit directly below the stratum of the hominin remains. The new pollen data from Ceprano are presented here in full for the first time and provide a detailed picture of interglacial vegetation development during Marine Isotope Stage (MIS) 13. This evidence contributes significantly to our knowledge of the spatial heterogeneity of ecosystem responses to climatic change during this period and helps to further constrain the age of the hominin remains. New sites combining both archaeology and long, continuous high quality palaeoecological records would help clarify the relationship between hominin presence and palaeoclimatic and palaeoenvironmental conditions. In the meantime, better communication between the research communities can also go a long way to improving our understanding of the links between the two.
Geogr. Fis. Dinam. Quat., 2019
The history of vegetation in the Italian peninsula during the last 2000 years was shaped by a com... more The history of vegetation in the Italian peninsula during the last 2000 years was shaped by a complex interplay of several factors, including the history of human societies, changes in land use, and the succession of
climate events. In order to disentangle these factors, we present a multidisciplinary
record from a marine core collected in the Gulf of Gaeta,
interpreted in the light of other palaeoenvironmental records from Tyrrhenian
Italy. Pollen records, complemented by new data on Non-Pollen
Palynomorphs (NPPs) and microcharcoal, are used to reconstruct changes in the vegetational landscape, stock-breeding activities, fire, and land use. Foraminiferal and oxygen isotope data provide independent information on climate changes. NAO-index and sunspot data support the interpretation of changes in atmospheric circulation. In this paper, by examining the
effect of climate and human activity on the landscape during a series of
periods of the last 2000 years, representing cultural or climate phases (Roman
Period, Dark Ages, Medieval Climate Anomaly, Little Ice Age, and Modern Period), we found that human impact produced a general and progressive decline of forest vegetation. However, irrespective of the societal cultural phase, forest declines occurred when negative NAO oscillations induced dry climate, especially during sunspot minima.
Catena, 2019
The development and decline of alder floodplain forests and alder carrs along the Tyrrhenian coas... more The development and decline of alder floodplain forests and alder carrs along the Tyrrhenian coasts, in relation to sea level changes, geomorphological processes, human activity, and climate change are presented and discussed. A number of 22 pollen records, complemented by Alnus macrofossil data, document the presence of widespread alder populations in the coastal Tyrrhenian floodplains throughout the Holocene, although with different density from one site to the other, mostly depending on local hydrological conditions. The role of climate changes in the dynamics of floodplain forests appears uncertain. In the last two centuries, major reclamation works disrupted this natural vegetation to obtain fertile plains that are now exploited for agricultural purposes, industrial activities, urban areas and related infrastructures. Only a few remnants of the original alder forests are preserved by international conservation conventions, as biodiversity reservoirs of severely endangered habitats. However, the vanished alder forests, which proved to be able to rapidly recover several times through the Holocene, may still have some potential to be restored.
Climate of the Past, 2019
In this paper, the variation in forest cover in the central Mediterranean region, reflected by pe... more In this paper, the variation in forest cover in the central Mediterranean region, reflected by percentage changes in the arboreal pollen record, has been examined in relation to the 4.2 ka event. A total of 36 well-dated and detailed pollen records from latitudes between 45 and 36 • N were selected and their vegetation dynamics between 5 and 3 ka examined in relation to the physiographic and climatic features of the study area and to the influence of human activity on past vegetation, as suggested by anthropogenic pollen indicators. We have found that the sites located between 43 and 45 • N do not show any significant vegetation change in correspondence with the 4.2 ka event. Several sites located on the Italian Peninsula between 39 and 43 • N show a marked opening of the forest, suggesting a vegetation response to the climate instability of the 4.2 ka event. Between 36 and 39 • N, a forest decline is always visible around 4.2 ka, and in some cases it is dramatic. This indicates that this region was severely affected by a climate change towards arid conditions that lasted a few hundred years and was followed by a recovery of forest vegetation in the Middle Bronze Age. Human activity, especially intense in southern Italy, may have been favored by this natural opening of vegetation. In Sar-dinia and Corsica, no clear change in vegetation is observed at the same time. We suggest that during the 4.2 ka event southern Italy and Tunisia were under the prevalent influence of a north African climate system characterized by a persistent high-pressure cell.
Quaternary Science Reviews, 2020
Inventories of species recently extinct or threatened with extinction may be found in global data... more Inventories of species recently extinct or threatened with extinction may be found in global databases. However, despite the large number of published fossil based-studies, specific databases on the vulnerability of species in the past are not available. We compiled a worldwide database of published fossil records of plant range losses over the last 30 ka across all continents. Widespread range losses of plant taxa across all latitudes were identified, with the majority representing gymnosperms. Focusing on conifers, a group of plants with well understood distribution and conservation status, we found that past range losses often overlapped areas where species are endangered at present, suggesting that such areas have been prone to biodiversity loss through time. During phases of past rapid climate change, even areas that currently have low levels of endangered species were affected by plant range losses, in some cases with disappearance of taxa from entire continents, islands or major geographic regions. Integration of modern and palaeoecological data enhance our understanding of the complex processes underlying the modes, rates, and extent of threats to plants under changing climate and increasing human pressure, which is vital information for effective conservation actions.
Review of Palaeobotany and Palynology, 2015
The New phytologist, 2014
Climate refugia, locations where taxa survive periods of regionally adverse climate, are thought ... more Climate refugia, locations where taxa survive periods of regionally adverse climate, are thought to be critical for maintaining biodiversity through the glacial-interglacial climate changes of the Quaternary. A critical research need is to better integrate and reconcile the three major lines of evidence used to infer the existence of past refugia - fossil records, species distribution models and phylogeographic surveys - in order to characterize the complex spatiotemporal trajectories of species and populations in and out of refugia. Here we review the complementary strengths, limitations and new advances for these three approaches. We provide case studies to illustrate their combined application, and point the way towards new opportunities for synthesizing these disparate lines of evidence. Case studies with European beech, Qinghai spruce and Douglas-fir illustrate how the combination of these three approaches successfully resolves complex species histories not attainable from any ...
Perspectives in Plant Ecology, Evolution and Systematics, 2012
The suggested location of broadleaved evergreen trees in Europe during the last full-glacial has ... more The suggested location of broadleaved evergreen trees in Europe during the last full-glacial has traditionally favoured a southerly refugial model, which proposes survival in the Mediterranean peninsulas and recolonization of central and northern Europe during the Holocene. This hypothesis is not always substantiated by thorough reviews of original past and modern occurrence data, or considered in the light of plant traits and autoecology. Our approach focuses on the genus Buxus with the aim of exploring (i) the relationship between the location of refugia and post-glacial population dynamics, (ii) past processes determining density, fragmentation and local extinctions of modern populations, and (iii) the vulnerability of Buxus in the context of the undergoing environmental changes. We compiled a database of over 3600 modern occurrences and 676 fossil sites to reconstruct the distribution of Buxus in Europe since 30 ka cal BP. The location of fossil finds and the plant traits of Buxus indicate that it persisted widely across its modern distribution through the last glacial period with modes varying from region to region. The E Pyrenees, W Alps, and Jura Mts hosted dense populations, which expanded exponentially during the whole Holocene, and resulted in a modern continuous distribution area. In contrast, the Mediterranean Peninsulas hosted sparse populations, which increased exponentially only during the first half of the Holocene, clearly decreased in the last 4.5 ka BP and resulted in a highly fragmented modern distribution area, most likely in relation to the climate trends towards dry conditions of the last few millennia. These results challenge the common view that the Mediterranean regions are the exclusive and most important refuge areas for evergreen broadleaved trees and stress the importance of considering long-term population dynamics based on fossil data to evaluate the vulnerability of modern fragmented plant populations in view of conservation actions.
Third Millennium BC Climate Change and Old World Collapse, 1997
Manuscri! legu le 1.. décembre lggg Absract. -ln the crater lake ofValle di Casliglione, artilìci... more Manuscri! legu le 1.. décembre lggg Absract. -ln the crater lake ofValle di Casliglione, artilìcially drìed up, sìtuated 20 km east of Rome, a borchole was drillcd-down ro a rtpúr oí ft in. eoiicn analysis is reprc\ented bolh on à pcrccnrrgc rli.rgrrm rn(t ,,n ir L\,ncc trírtr,rr Oragmm.. l-lonstic, veget ional. pîlncoccol(!gicul. pJlrljùclintîrie. hi(,\rrrti. grupnrcat ano cnronotogrcal a\pccls are disfusscd.
PloS one, 2015
The Ficoncella site in northern Latium (Italy) represents a unique opportunity to investigate the... more The Ficoncella site in northern Latium (Italy) represents a unique opportunity to investigate the modalities of a short occupation in an alluvial setting during the Lower Palaeolithic. The small excavation area yielded a lithic assemblage, a carcass of Palaeoloxodon antiquus, and some other faunal remains. The main objectives of the study are to better characterize the depositional context where the Palaeoloxodon and the lithic assemblage occur, and to evaluate with greater precision the occupation dynamics. A 25 m-long well was drilled just above the top of the terrace of the Ficoncella site and faunal and lithic remains were analyzed with current and innovative techniques. The archaeological site contains floodplain deposits as it is located next to a small incised valley that feeds into a larger valley of the Mignone River. A tephra layer capping the site is 40Ar/39Ar dated to 441± 8 ka. Collectively, the geochronologic, tephrochronologic and geologic data, suggest the site was o...
Review of Palaeobotany and Palynology, 2014
A new pollen and plant macrofossil record from Pesce Luna (Fiumicino, Rome) provides the reconstr... more A new pollen and plant macrofossil record from Pesce Luna (Fiumicino, Rome) provides the reconstruction of the vegetation history in the Tiber Delta region between 13,000 and 8400 cal. BP. Marked fluctuations of hydro-and hygrophytes depict a variety of marsh-lagoon conditions reflecting marked changes in water-table level and salinity, determined by the transition from a continental environment with a strong fluvial influence, to a freshwater/brackish environment typical of an inner estuary, followed by a saline outer estuary environment. Both deciduous (mostly Quercus, Corylus, Tilia, Ulmus and Fagus) and evergreen elements (evergreen Quercus and Ericaceae) were already present during the Younger Dryas, being possibly enhanced by water availability and the vicinity to the sea that may have favoured long-term persistence of tree populations. Evergreen populations progressively increased during the early Holocene. Despite the strong effect of local environmental processes, a comparison of the Pesce Luna pollen record with other southern European sequences and the GISP2 δ 18 O record indicates that the vegetation development was also influenced by centennial-scale climate processes acting at global scale. In particular, a mid-Younger Dryas climate reversal can be recognized at Pesce Luna, similar to other Mediterranean sites both in marine and continental environments. This study improves our knowledge on the vulnerability and resilience of coastal-estuarine wetlands to the global warming and sea level rise of the last deglaciation, adding insights into the response of coastal environments to the predicted global climate changes.
European Journal of Echocardiography, 2006
Eur J Echocardiography Abstracts Supplement, December 2006 p<0.05) respect to control group; a si... more Eur J Echocardiography Abstracts Supplement, December 2006 p<0.05) respect to control group; a significant higher myocardial IBS at septum (53.3±20.7 vs 43.4±7.1%, p<0.05), but comparable at the posterior wall level (33.6±13 vs 32.5±9.3%, p=ns) respect to the control group; a lower CVI in DM1 group both at septum (11.3±17.7 vs 37±9.9%, p<0.0001) and posterior wall level (23.2±17.9 vs 43.6±12.7%, p<0.0001).
Review of Palaeobotany and Palynology, 2014
Sedimentary Geology, 2013
This paper presents a detailed description of the stratigraphic architecture of the Late Pleistoc... more 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), 14 C 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 facies, foraminifer and ostracod assemblages, pollen and 14 C 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.
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Papers by Donatella Magri
Taranto Gulf, south Adriatic Sea and Israel) has been proposed. The correlation of data testifies an almost synchronicity of the identified climate events, suggesting an homogeneous response of the marine system to climate oscillations. This overall picture documents that the collapse of the Western Roman Empire results chronologically related to cold event
Roman III solar minimum and that the Roman IV solar minimum (Dark
Age), marks the transition vs a long term cooling trend, spanning ca.
1100 years, that culminates during the Maunder solar minimum (LIA).
In addition, during the Maunder cold event, the strong increase in abundance of planktonic foraminifer Globlorotalia truncatulinoides, suggest the establishment of vertical mixing during the winter season induced by strong winds linked to an atmospheric blocking event.
climate events. In order to disentangle these factors, we present a multidisciplinary
record from a marine core collected in the Gulf of Gaeta,
interpreted in the light of other palaeoenvironmental records from Tyrrhenian
Italy. Pollen records, complemented by new data on Non-Pollen
Palynomorphs (NPPs) and microcharcoal, are used to reconstruct changes in the vegetational landscape, stock-breeding activities, fire, and land use. Foraminiferal and oxygen isotope data provide independent information on climate changes. NAO-index and sunspot data support the interpretation of changes in atmospheric circulation. In this paper, by examining the
effect of climate and human activity on the landscape during a series of
periods of the last 2000 years, representing cultural or climate phases (Roman
Period, Dark Ages, Medieval Climate Anomaly, Little Ice Age, and Modern Period), we found that human impact produced a general and progressive decline of forest vegetation. However, irrespective of the societal cultural phase, forest declines occurred when negative NAO oscillations induced dry climate, especially during sunspot minima.
Taranto Gulf, south Adriatic Sea and Israel) has been proposed. The correlation of data testifies an almost synchronicity of the identified climate events, suggesting an homogeneous response of the marine system to climate oscillations. This overall picture documents that the collapse of the Western Roman Empire results chronologically related to cold event
Roman III solar minimum and that the Roman IV solar minimum (Dark
Age), marks the transition vs a long term cooling trend, spanning ca.
1100 years, that culminates during the Maunder solar minimum (LIA).
In addition, during the Maunder cold event, the strong increase in abundance of planktonic foraminifer Globlorotalia truncatulinoides, suggest the establishment of vertical mixing during the winter season induced by strong winds linked to an atmospheric blocking event.
climate events. In order to disentangle these factors, we present a multidisciplinary
record from a marine core collected in the Gulf of Gaeta,
interpreted in the light of other palaeoenvironmental records from Tyrrhenian
Italy. Pollen records, complemented by new data on Non-Pollen
Palynomorphs (NPPs) and microcharcoal, are used to reconstruct changes in the vegetational landscape, stock-breeding activities, fire, and land use. Foraminiferal and oxygen isotope data provide independent information on climate changes. NAO-index and sunspot data support the interpretation of changes in atmospheric circulation. In this paper, by examining the
effect of climate and human activity on the landscape during a series of
periods of the last 2000 years, representing cultural or climate phases (Roman
Period, Dark Ages, Medieval Climate Anomaly, Little Ice Age, and Modern Period), we found that human impact produced a general and progressive decline of forest vegetation. However, irrespective of the societal cultural phase, forest declines occurred when negative NAO oscillations induced dry climate, especially during sunspot minima.