Search results for "pre"
showing 10 items of 50649 documents
Reconstruction of late Holocene autumn/winter precipitation variability in SW Romania from a high-resolution speleothem trace element record
2018
We present the first high-resolution trace element (Mg/Ca, Sr/Ca, Ba/Ca) record from a stalagmite in southwestern Romania covering the last 3.6 ka, which provides the potential for quantitative climate reconstruction. Precise age control is based on three independent dating methods, in particular for the last 250 yr, where chemical lamina counting is combined with the identification of the 20th century radiocarbon bomb peak and Th-230/U dating. Long-term cave monitoring and model simulations of drip water and speleothem elemental variability indicate that precipitation-related processes are the main drivers of speleothem Mg/Ca ratios. Calibration against instrumental climate data shows a si…
The owl that never left! Taphonomy of Earlier Stone Age small mammal assemblages from Wonderwerk Cave (South Africa)
2022
Wonderwerk Cave, in South Africa, is an exceptional site that has yielded a large collection of small mammal fossils in a stratigraphic sequence reaching back ca. 2 million years. Taphonomic studies undertaken to date, show that Tytonidae (likely Tyto alba) was the dominant predator during the Earlier Stone Age. They produced masses of pellets that formed a dense carpet-like surface that covered the cave floor at intervals throughout the sequence. This paper compares the taphonomic signatures of five different Earlier Stone Age small mammal assemblages from Wonderwerk Cave, including assemblages not studied before, as well as a modern pellet assemblage collected from inside the cave. These …
Landscape and fuel management in the context of prehistoric and historical occupations of Cova des Moro (Manacor, Mallorca, Spain)
2021
Abstract In this paper, the first results of charcoal analyses carried out at Cova des Moro (Manacor, Mallorca, Spain) are presented. This cave is an archaeological but also palaeontological site that provides information on endemic fauna (the extinct caprine Myotragus balearicus) before the arrival of humans and, later, the relationship between the first farmers and the landscape. Several human occupations in the cave have been documented, from the Chalcolithic (end of the 3rd millennium cal BC), the Bronze Age (2nd millennium cal BC) and, finally, the Almohad period (13th century AD), during which the cave was used for different purposes. The first results of charcoal analyses at Cova des…
Speleothems from the Middle East: An Example of Water Limited Environments in the SISAL Database
2019
The Middle East (ME) spans the transition between a temperate Mediterranean climate in the Levant to hyper-arid sub-tropical deserts in the southern part of the Arabian Peninsula (AP), with the complex alpine topography in the northeast feeding the Euphrates and Tigris rivers which support life in the Southeastern Fertile Crescent (FC). Climate projections predict severe drying in several parts of the ME in response to global warming, making it important to understand the controls of hydro-climate perturbations in the region. Here we discuss 23 ME speleothem stable oxygen isotope (δ18Occ) records from 16 sites from the SISAL_v1 database (Speleothem Isotope Synthesis and Analysis database), …
Dietary evidence from Central Asian Neanderthals: A combined isotope and plant microremains approach at Chagyrskaya Cave (Altai, Russia).
2021
Neanderthals are known primarily from their habitation of Western Eurasia, but they also populated large expanses of Northern Asia for thousands of years. Owing to a sparse archaeological record, relatively little is known about these eastern Neanderthal populations. Unlike in their western range, there are limited zooarchaeological and paleobotanical studies that inform us about the nature of their subsistence. Here, we perform a combined analysis of carbon and nitrogen stable isotopes on bone collagen and microbotanical remains in dental calculus to reconstruct the diet of eastern Neanderthals at Chagyrskaya Cave in the Altai Mountains of Southern Siberia, Russia. Stable isotopes identify…
L’étude archéologique des mortiers de chaux médiévaux : vers une meilleure compréhension des gestes du maçon
2020
International audience; Ces dernières décennies, l’étude des mortiers archéologiques, en particulier médiévaux, a connu un essor considérable en lien étroit avec celui de l’archéologie du bâti. Matériaux composites, possédant à la fois une forte identité géologique et un caractère anthropique certain, les mortiers sont considérés comme étant des marqueurs chronologiques potentiels pouvant aider à la compréhension de l’évolution d’un bâtiment. Mais, au-delà des problèmes de chronologie, l’étude du mortier de chaux, qui représente près de la moitié du volume d’une maçonnerie, a permis également de progresser sur la connaissance de toute la chaîne opératoire associée. Ainsi, du four à chaux au…
À l’aube des villes antiques : vocabulaire de la cité et formes urbaines. – Introduction
2020
How to envisage research on the ancient city? What are the most appropriate instruments to analyse it? What are the relationships between the emergence of the city as an independent community and the urbanization as archaeology can restore it? Without claiming to resolve these difficult questions, the contributions gathered here show that urbanization and the definitions of the ancient city used by contemporary historians and archaeologists are far from being precisely determined; they can even vary according to the authors, disciplines, periods and contexts. As a consequence, there is no town, but towns; no city, but cities. The issue of a definition is also the evaluation of theories, in …
Late Holocene seasonal temperature variability of the western Scottish shelf (St Kilda) recorded in fossil shells of the bivalve Glycymeris glycymeris
2021
Abstract The North Atlantic Ocean and adjacent shelf seas play a crucial role in global climate. To better constrain long-term natural variability and marine-terrestrial linkages in this region, a network of highly resolved marine archives from the open ocean and continental shelves is needed. In recent decades, bivalve sclerochronology has emerged as a field providing such records from the mid- to high latitudes. In May 2014, dead valves and young live specimens of the bivalve Glycymeris glycymeris were collected at St Kilda, Scotland. A floating chronology spanning 187 years was constructed with fossil shells and radiocarbon dated to 3910–3340 cal yr before present (BP), with a probabilit…
« On-the-go » multispectral imaging system to characterize the development of vineyard foliage
2015
International audience; In Precision Viticulture, multispectral imaging systems are currently used in remote sensing for vineyard vigor characterization but few are employed in proximal sensing. This work presents the potential of a proximal multispectral imaging system mounted on a track-laying tractor equipped with a Greenseeker RT-100 to provide an NDVI index. The camera acquired visible and near-infrared images which were calibrated in reflectance. Vegetation indices were computed and compared to Greenseeker data. From two of the resulting datasets, a spatio-temporal study of foliage description through both optical systems is presented. This first study assessed the proximal imagery re…
Citizen Science in the Natural Sciences
2021
AbstractThe natural sciences include the life and physical sciences and study nature through observing and understanding phenomena, testing hypotheses, and performing experiments. Key principles such as reliability, validity, objectivity, and predictability are achieved through transparent assumptions, methods, data, and interpretations as well as multidisciplinarity.In this chapter we present insights into the genesis of citizen science in the natural sciences and reflect on the intellectual history of the natural sciences in relation to citizen science today. Further, we consider the current scientific approaches and achievements of natural science projects, which are applying citizen sci…