Palaeoproductivity and environmental changes during the Holocene in central Italy as recorded in two crater lakes (Albano and Nemi)

The stratigraphic study of the Stagno di Maccarese, carried out on the sediments exposed in about 7 km of trenches excavated in an area of approximately 1.5 km2, has shown that in the course of the Holocene many environmental variations have taken place. The complex evolution of the marsh is demonstrated by the variations in water salinity and the presence of erosion surfaces and soils between the sediments. In the early Holocene, the area studied was an isolated marsh with water having variable salinity, and it was only about 6000 cal. yr BP that it was encompassed in the system of inner delta marshes. In the delta environment, the water of the marsh was oligohaline until about 9th–8th centuries bc, brackish from 9th–8th centuries bc to about 600 yr BP, and later oligohaline until the 19th century drainage. A number of environmental variations are connected with local phenomena, such as erosion of the beach ridges and Tiber floods, but the others can be correlated chronologically with climatic events recorded at regional and global scale. The millennial variations seem to be connected with changes in insolation, while abrupt variations can be correlated chronologically with the IRD events dated at 8200, 5900, 4200, 2800, 1400 and 500 cal. yr BP.

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Constraining the onset of the Holocene “Neoglacial” over the central Italy using tephra layers

Quaternary Research ◽

10.1016/j.yqres.2012.05.010 ◽

2012 ◽

Vol 78 (2) ◽

pp. 236-247 ◽

Cited By ~ 48

Author(s):

Giovanni Zanchetta ◽

Carlo Giraudi ◽

Roberto Sulpizio ◽

Michel Magny ◽

Russell N. Drysdale ◽

...

Keyword(s):

Environmental Changes ◽

Central Italy ◽

Climatic Changes ◽

Common Method ◽

Chemical Analyses ◽

High Mountains ◽

Central Apennines ◽

The Holocene ◽

Tephra Layers ◽

Apennine Chain

AbstractA study of six tephra layers discovered in different deposits between 1600 and 2700 m a.s.l. in the Apennine chain in central Italy allowed precise stratigraphic constraints on environmental and climatic changes between ca. 4.5 and 3.8 cal ka BP. Chemical analyses allowed the correlation of these tephra layers with the eruptions of Agnano Mt Spina (AMST) from Phlegrean Field and Avellino (AVT) from Somma–Vesuvius. Major environmental changes in the high mountains of the Central Apennines occurred just after the deposition of the AMST and predate the deposition of the AVT. At this time, renewed growth of the Calderone Glacier occurred, marking the onset of the Apennine “Neoglacial”. The presence of the AMST and AVT enabled us to make a precise, physical correlation with other archives in central Italy. Synchronization of records between sites showed that the period intervening the deposition of the AMST and AVT layers coincided with environmental changes that were not always exactly in phase. This highlights the fact that stratigraphic correlations using only radiocarbon chronologies (the most common method used for dating archives during the Holocene) could produce erroneous correlation of events, giving rise to oversimplified paleoclimatic reconstructions.

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Environmental evolution and anthropogenic forcing in the Garigliano coastal plain (Italy) during the Holocene

The Holocene ◽

10.1177/09596836211003242 ◽

2021 ◽

pp. 095968362110032

Author(s):

Halinka Di Lorenzo ◽

Pietro Aucelli ◽

Giuseppe Corrado ◽

Mario De Iorio ◽

Marcello Schiattarella ◽

...

Keyword(s):

Human Activity ◽

Coastal Plain ◽

Forest Cover ◽

Environmental Changes ◽

Pollen Data ◽

Human Environment ◽

The Holocene ◽

Natural Processes ◽

History Of ◽

The Rich

The Garigliano alluvial-coastal plain, at the Latium-Campania border (Italy), witnessed a long-lasting history of human-environment interactions, as demonstrated by the rich archaeological knowledge. With the aim of reconstructing the evolution of the landscape and its interaction with human activity during the last millennia, new pollen results from the coastal sector of the Garigliano Plain were compared with the available pollen data from other nearby sites. The use of pollen data from both the coastal and marine environment allowed integrating the local vegetation dynamics within a wider regional context spanning the last 8000 years. The new pollen data presented in this study derive from the analysis of a core, drilled in the coastal sector, which intercepted the lagoon-marshy environments that occurred in the plain as a response to the Holocene transgression and subsequent coastal progradation. Three radiocarbon ages indicate that the chronology of the analyzed core interval ranges from c. 7200 to c. 2000 cal yr BP. The whole data indicate that a dense forest cover characterized the landscape all along the Prehistoric period, when a few signs of human activity are recorded in the spectra, such as cereal crops, pasture activity and fires. The main environmental changes, forced by natural processes (coastal progradation) but probably enhanced by reclamation works, started from the Graeco-Roman period and led to the reduction of swampy areas that favoured the colonisation of the outer plain.

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Holocene sea level and climate interactions on wet dune slack evolution in SW Portugal: A model for future scenarios?

The Holocene ◽

10.1177/0959683618804633 ◽

2018 ◽

Vol 29 (1) ◽

pp. 26-44 ◽

Cited By ~ 2

Author(s):

Manel Leira ◽

Maria C Freitas ◽

Tania Ferreira ◽

Anabela Cruces ◽

Simon Connor ◽

...

Keyword(s):

Sea Level Rise ◽

Sea Level ◽

Environmental Changes ◽

Sediment Accumulation ◽

High Energy ◽

Sediment Supply ◽

Dune Slack ◽

Ecological Stability ◽

The Holocene ◽

Climate Interactions

We examine the Holocene environmental changes in a wet dune slack of the Portuguese coast, Poço do Barbarroxa de Baixo. Lithology, organic matter, biological proxies and high-resolution chronology provide estimations of sediment accumulation rates and changes in environmental conditions in relation to sea-level change and climate variability during the Holocene. Results show that the wet dune slack was formed 7.5 cal. ka BP, contemporaneous with the last stages of the rapid sea-level rise. This depositional environment formed under frequent freshwater flooding and water ponding that allowed the development and post-mortem accumulation of abundant plant remains. The wetland evolved into mostly palustrine conditions over the next 2000 years, until a phase of stabilization in relative sea-level rise, when sedimentation rates slowed down to 0.04 mm yr−1, between 5.3 and 2.5 cal. ka BP. Later, about 0.8 cal. ka BP, high-energy events, likely due to enhanced storminess and more frequent onshore winds, caused the collapse of the foredune above the wetlands’ seaward margin. The delicate balance between hydrology (controlled by sea-level rise and climate change), sediment supply and storminess modulates the habitat’s resilience and ecological stability. This underpins the relevance of integrating past records in coastal wet dune slacks management in a scenario of constant adaptation processes.

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Stepwise Weakening of Aeolian Activities During the Holocene in the Gannan Region, Eastern Tibetan Plateau

Frontiers in Earth Science ◽

10.3389/feart.2021.686677 ◽

2021 ◽

Vol 9 ◽

Author(s):

Shengli Yang ◽

Xiaojing Liu ◽

Ting Cheng ◽

Yuanlong Luo ◽

Qiong Li ◽

...

Keyword(s):

Tibetan Plateau ◽

Environmental Changes ◽

Climatic Changes ◽

Early Holocene ◽

Eastern Tibetan Plateau ◽

Aeolian Desertification ◽

The Holocene ◽

Aeolian Sediments ◽

Aeolian Activity ◽

History Of

Aeolian sediments hold key information on aeolian history and past environmental changes. Aeolian desertification and extensive land degradation have seriously affected the eco-environment in the Gannan region on the eastern Tibetan Plateau. Understanding the history of aeolian activities can deepen our understanding of the impacts of climatic changes on aeolian activities in the future. This study uses a detailed chronology and multiple proxy analyses of a typical aeolian section in Maqu to reconstruct aeolian activities in the region during the Holocene. Our results showed that aeolian activities have occurred in the eastern Tibetan Plateau since the early Holocene. Magnetic susceptibility, grain size records, and paleosols formation indicated a trend of stepwise weakening in aeolian activities from the early Holocene to the present. The weakening of aeolian activities was divided into three stages: ∼10.0–8.0 ka BP, ∼8.0–4.0 ka BP, and ∼4.0 ka BP to the present. Paleosols were primarily formed after ∼8.0 ka BP, and episodically interrupted aeolian activities processes in the Gannan region. Aeolian activity may increase in the Gannan region as the climate gradually warms. Climatic changes and local hydrological conditions have jointly affected the history of aeolian activities in this region.

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Penguin occupation in the Vestfold Hills

Antarctic Science ◽

10.1017/s095410200800165x ◽

2008 ◽

Vol 21 (2) ◽

pp. 131-134 ◽

Cited By ~ 11

Author(s):

Tao Huang ◽

Liguang Sun ◽

Yuhong Wang ◽

Renbin Zhu

Keyword(s):

Sediment Core ◽

Environmental Changes ◽

Sediment Cores ◽

East Antarctica ◽

Before Present ◽

The Holocene ◽

History Of ◽

Vestfold Hills ◽

Free Area ◽

Ornithogenic Sediment

AbstractDuring CHINARE-22 (December 2005–March 2006), we investigated six penguin colonies in the Vestfold Hills, East Antarctica, and collected several penguin ornithogenic sediment cores, samples of fresh guano and modern penguin bone and feather. We selected seven penguin bones and feathers and six sediments from the longest sediment core and performed AMS14C dating. The results indicate that penguins occupied the Vestfold Hills as early as 8500 calibrated years before present (cal. yrbp), following local deglaciation and the formation of the ice free area. This is the first report on the Holocene history of penguins in the Vestfold Hills. As in other areas of Antarctica, penguins occupied this area as soon as local ice retreated and the ice free area formed, and they are very sensitive to climatic and environmental changes. This work provides the foundation for understanding the history of penguins occupation in Vestfold Hills, East Antarctica.

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Expressions of climate perturbations in western Ugandan crater lake sediment records during the last 1000 yr

Climate of the Past Discussions ◽

10.5194/cpd-9-5183-2013 ◽

2013 ◽

Vol 9 (5) ◽

pp. 5183-5226 ◽

Cited By ~ 3

Author(s):

K. Mills ◽

D. B. Ryves ◽

N. J. Anderson ◽

C. L. Bryant ◽

J. J. Tyler

Keyword(s):

Environmental Change ◽

East Africa ◽

Environmental Changes ◽

Sediment Cores ◽

Ice Age ◽

Ecosystem Response ◽

Large Lakes ◽

Crater Lakes ◽

Continental Scale ◽

Western Uganda

Abstract. Equatorial East Africa has a complex, regional patchwork of climate regimes, with multiple interacting drivers. Recent studies have focussed on large lakes and reveal signals that are smoothed in both space and time, and, whilst useful at a continental scale, are of less relevance when understanding short-term, abrupt or immediate impacts of climate and environmental changes. Smaller-scale studies have highlighted spatial complexity and regional heterogeneity of tropical palaeoenvironments in terms of responses to climatic forcing (e.g. the Little Ice Age [LIA]) and questions remain over the spatial extent and synchroneity of climatic changes seen in East African records. Sediment cores from paired crater lakes in western Uganda were examined to assess ecosystem response to long-term climate and environmental change as well as testing responses to multiple drivers using redundancy analysis. These archives provide annual to sub-decadal records of environmental change. The records from the two lakes demonstrate an individualistic response to external (e.g. climatic) drivers, however, some of the broader patterns observed across East Africa suggest that the lakes are indeed sensitive to climatic perturbations such as a dry Mediaeval Climate Anomaly (MCA; 1000–1200 AD) and a relatively drier climate during the main phase of the LIA (1500–1800 AD); though lake levels in western Uganda do fluctuate. The relationship of Ugandan lakes to regional climate drivers breaks down c. 1800 AD, when major changes in the ecosystems appear to be a response to sediment and nutrient influxes as a result of increasing cultural impacts within the lake catchments. The data highlight the complexity of individual lake response to climate forcing, indicating shifting drivers through time. This research also highlights the importance of using multi-lake studies within a landscape to allow for rigorous testing of climate reconstructions, forcing and ecosystem response.

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