Search results for "LATE HOLOCENE"

Holocene sea level change in Malta

2013

A multidisciplinary approach has been applied to study sea level changes along the coast of Malta using data collected from underwater archaeological remains. The elevation of archaeological markers have been compared with predicted sea level curves providing new bodies of evidence that outline the vertical tectonic behaviour of this region, allowing estimation of the relative sea level changes that occurred in this area of the Mediterranean since the Bronze Age. During the Roman Age, sea level was at −1.36 ± 0.1 m, while in the Midde Age it was at −0.56 ± 0.2 m, in agreement with previous estimations for the Mediterranean region. Data indicate that Malta was tectonically stable during the …

Drivers of peat accumulation rate in a raised bog: impact of drainage, climate, and local vegetation composition

2017

We used variation partitioning to assess the relative importance of drainage, climate and local vegetation composition for the development of a raised bog. As a case study we selected Teici (Teici) Bog in Latvia (north-east Europe). Explanatory variables together explained 74 % of the variation in peat accumulation and only the residue of 26 % remained unexplained. Our study showed that the local vegetation composition and dominant Sphagnum species significantly influence peat accumulation rates. The results of linear models revealed that, under natural conditions, minor drainage and even strong drainage of the peat is associated with a positive growth balance of the system. However, draina…

Climatic variability and anthropogenic signatures in the Gulf of Salerno (southern-eastern Tyrrhenian Sea) during the last half-millennium

2012

Organic lacustrine sediment varves as indicators of past precipitation changes: a 3,000-year climate record from Central Finland

2015

Annually laminated (varved) sediments from Lake Kallio-Kourujärvi, Central Finland, provide high-resolution sedimentological data for the last three millennia. These varves consist of two laminae that represent (1) deposition during the spring-to-autumn growing season, composed of degraded organic matter and a variety of microfossils, and (2) deposition during winter, composed of fine-grained homogenous organic matter. Because of the absence of a clastic lamina, these varves differ from the typical, well-described, clastic-organic varve sequences in Fennoscandian lakes. Such organic varves in Finnish lakes have not been studied in detail before. Three thousand varves were counted and their …

Biogeochemical cycling and ecological thresholds in a High Arctic lake (Svalbard)

2019

Lakes are a dominant feature of the Arctic landscape and a focal point of regional and global biogeochemical cycling. We collected a sediment core from a High Arctic Lake in southwestern Svalbard for multiproxy paleolimnological analysis. The aim was to find linkages between the terrestrial and aquatic environments in the context of climate change to understand centennial-long Arctic biogeochemical cycling and environmental dynamics. Two significant thresholds in elemental cycling were found based on sediment physical and biogeochemical proxies that were associated with the end of the cold Little Ice Age and the recent warming. We found major shifts in diatom, chironomid and cladoceran comm…

Landscape Systems and Human Land-Use Interactions in Mediterranean Highlands and Littoral Plains during the Late Holocene: Integrated Analysis from t…

2012

The main goal of the InterAmbAr reseach project is to analyze the relationships between landscape systems and human land-use strategies on mountains and littoral plains from a long-term perspective. The study adopts a high resolution analysis of small-scale study areas located in the Mediterranean region of north-eastern Catalonia. The study areas are distributed along an altitudinal transect from the high mountain (above 2000m a.s.l.) to the littoral plain of Empordà (Fig. 1). High resolution interdisciplinary research has been carried out from 2010, based on the integration of palaeoenvironmental and archaeological data. The micro-scale approach is used to understand human-environmental r…

1200-yr high-resolution terrestrial climate archive from the middle of the Mediterranean: The sedimentary record from Lake “Specchio di Venere” on Pa…

2011

The special location of Lake "Specchio di Venere" on Pantelleria Island in the Sicily Channel (Mediterranean Sea) between Tunisia and Sicily offers a unique terrestrial archive recording atmospheric changes, which are otherwise difficult to decipher in the marine records from this area. The lake is an endorheic saline basin with a maximum depth of 12.5 m. As the water input depends on rainfall, precipitation variations influence changes of the lake's water chemistry. In summer 2008, Lake Venere was cored with a modified Livingstone corer revealing a composite sedimentary sequence of 10.29 m length. Two radiocarbon dates form a preliminary age model indicating a very high sedimentation rate …

Abrupt Alnus population decline at the end of the first millennium CE in Europe - The event ecology, possible causes and implications

2019

The study, based on the examination of 70 published and unpublished pollen profiles from Poland and supplementary data from the surrounding regions, shows that an abrupt, episodic Alnus population decline at the end of the first millennium CE was a much more widespread event than has been previously reported, spanning large areas of the temperate and boreal zones in Europe. The data from Poland suggest that the decline was roughly synchronous and most likely occurred between the 9th and 10th centuries, with strong indications for the 10th century. The pollen data indicate that human impacts were not a major factor in the event. Instead, we hypothesize that one or a series of abrupt climatic…

Arheoloģija Baltijā 21. gs. sākumā: jaunākie pētījumi, aktuālās diskusijas un mūsdienu izaicinājumi: referātu kopsavilkumi, 2022. gada 18. februārī L…

2022

Jau divas desmitgades Latvijas Universitātes (LU) starptautiskās zinātniskās konferences ietvaros katru otro gadu norisinās Arheoloģijas sekcija, ko rīko LU Vēstures un filozofijas fakultāte. Pirmoreiz šāda sekcija tika rīkota LU 61. zinātniskajā konferencē 2003. gada 10. februārī. Turpinot iesākto tradīciju, arī 2022. gada 18. februārī LU 80. starptautiskās konferences ietvaros Vēstures un filozofijas fakultātes Vēstures un arheoloģijas nodaļa organizēja arheoloģijas problemātikai veltītu sekciju, kurā tika aplūkotas daudzveidīgās un aktuālās mūsdienu arheoloģijas attīstības tendences Latvijā un Eiropā. Daļa konferences referātu pievērsās dabaszinātņu un tās pētniecisko metožu lomai arheol…

A new marker for sea surface temperature trend during the last centuries in temperate areas: Vermetid reef

2004

The presence of Vermetid reefs in temperate waters, their diffusion in the Mediterranean Sea, and the possibility of performing 14 C ages allowed the use of Vermetids as an indicator of sea level changes. We present new data on sea climate trend fluctuations that could be interpreted as Sea Surface Temperature (SST) variations, recorded on Vermetid (Dendropoma petraeum) reefs, by means of isotopic analysis. The isotopic records show positive values of the d 18 O relative to present-day values in the period between 1600 and 1850 AD; this deviation occurs in association with the climatic cooling event known as Little Ice Age (LIA). Subsequently, we can observe the warming trend that character…