Search results for "Macrofossil"
showing 10 items of 25 documents
A multi-proxy long-term ecological investigation into the development of a late Holocene calcareous spring-fed fen ecosystem (Raganu Mire) and boreal…
2021
Abstract The calcareous substrate of spring-fed fens makes them unique islands of biodiversity, hosting endangered, vulnerable, and protected vascular plants. Hence, spring-fed fens ecosystems require special conservation attention because many of them are destroyed (e.g. drained, forested) and it is extremely difficult or even impossible to restore the unique hydrogeological and geochemical conditions enabling their function. The long-term perspective of paleoecological studies allows indication of former wetland ecosystem states and provides understanding of their development over millennia. To examine the late Holocene dynamics of a calcareous spring-fed fen (Raganu Mire) ecosystem on th…
Comparison of quantitative Holocene temperature reconstructions using multiple proxies from a northern boreal lake
2017
Four biotic proxies (plant macrofossils, pollen, chironomids and diatoms) are employed to quantitatively reconstruct variations in mean July air temperatures ( Tjul) at Lake Loitsana (northern Finland) during the Holocene. The aim is to evaluate the robustness and biases in these temperature reconstructions and to compare the timing of highest Tjul in the individual reconstructions. The reconstructed Tjul values are evaluated in relation to local-scale/site-specific processes associated with the Holocene lake development at Loitsana as these factors have been shown to significantly influence the fossil assemblages found in the Lake Loitsana sediments. While pollen-based temperatures follow…
Last Millennium hydro-climate variability in Central–Eastern Europe (Northern Carpathians, Romania)
2015
Proxy-based reconstructions of climate variability over the last millennium provide important insights for understanding current climate change within a long-term context. Past hydrological changes are particularly difficult to reconstruct, yet rainfall patterns and variability are among the most critical environmental variables. Ombrotrophic bogs, entirely dependent on water from precipitation and sensitive to changes in the balance between precipitation and evapotranspiration, are highly suitable for such hydro-climate reconstructions. We present a multi-proxy analysis (testate amoebae, plant macrofossils, stable carbon isotopes in Sphagnum, pollen, spores and macroscopic charcoal) from …
Une occupation du Bronze final et sa nécropole à Metz – ZAC du Sansonnet (Moselle). Un cas particulier de stabilisation d’un habitat.
2020
International audience
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…
Pollen and Plant Macroremain Analyses for the Reconstruction of Environmental Changes in the Early Metal Period
2006
A sharp increase in human population density and the same time fundamental changes in the location of settlement, moving away from earlier inhabited places points to significant changes in the environment. This period with a sharp decrease in anthropogenic indicators and poor records of slash and burn cultivation and field crop-growing is named “transition” period (Vasks et.al.1998) and indicates the lack of stable and continuous inhabitant sites. This phenomena can be explained by the small size of settlements at the Early Iron Age, expressed by a weak cultural layer and these could be defined as separate farmsteads. Modern farming practices, especially modern tillage, adversely affected t…
Zonation by ammonites and foraminifers of the Vraconnian-Turonian interval: A comparison of the Boreal and Tethyan domains (NW Europe / Central Tunis…
2008
International audience; Since the end of the 19th century the interval comprising the uppermost Upper Albian, the Cenomamian, the Turonian and the basal Coniacian has been subdivided, first into ammonite zones, then, beginning in the middle of the 20th century, into zones of planktonic foraminifera. These two groups, one macrofossil, the other microfossil, are particularly effective for bio-chronostratigraphy thanks to their rapid rates of evolution. But differences in the faunal makeup between the Boreal domain (northwestern Europe) and the Tethyan domain (Mediterranean) have for a long time hindered precise correlation of the two domains. Today, in a time interval covering about 16 millio…
Plant macrofossil, pollen and invertebrate analysis of a mid-14th century cesspit from medieval Riga, Latvia (the eastern Baltic): Taphonomy and indi…
2017
The paper presents the results of an integrated environmental analysis on the fill of an exceptionally well-preserved mid-14th century cesspit from the historic centre of Riga (Latvia, eastern Baltic). Palynological, plant macrofossils and invertebrate analysis yielded important new information about the use of plants by the indigenous community living within the medieval city, including their socio-economic status. The taphonomy of the botanical and invertebrate data is considered to largely reflect the input of undigested food waste and human faecal material with a subordinate component derived through the input of cereal waste-products. The results show that the diet of the indigenous co…
Holocene vegetation and fire dynamics in the supra-mediterranean belt of the Nebrodi Mountains (Sicily, Italy).
2012
High-resolution pollen, macrofossil and charcoal data, combined with accelerator mass spectrometry 14C dating and multivariate analysis, were used to reconstruct Holocene vegetation and fire dynamics at Urio Quattrocchi, a small lake in the supra-mediterranean belt in the Nebrodi Mountains of Sicily (Italy). The data suggest that after 10 000 cal a BP increasing moisture availability supported closed forests with deciduous (Quercus cerris, Fagus sylvatica and Fraxinus spp.) and evergreen (Quercus ilex) species. Species-rich closed forest persisted until 6850 cal a BP, when Neolithic activities caused a forest decline and affected plant diversity. Secondary forest with abundant Ilex aquifoli…
Recension of Collins, M.E., Manchester, S.R. & Wilde, W. 2012
2020
Collins, M.E., Manchester, S.R. & Wilde, W. 2012. Fossil fruits and seeds of the Middle Eocene Messel biota, Germany.Abhandlungen der Senckenberg Gessellschaft für Naturforschung, 570, 251 pp. ISBN 978-3-510-61400-4 This book presents a survey of the extensive fruit and seed collection found at the Middle Eocene Messel site. The first part of the book is dedicated to a few introductory chapters about the site, geologic setting, age control of the sedimentary sequence and taphonomy of the fossil remains. It is worth pointing out that unlike many lacustrine deposits in which fruits are preserved as impressions, most of the Messel plant macrofossils are preserved as remnants of the original pl…