Search results for "LAI"
showing 10 items of 6640 documents
The response of a shallow lake and its catchment to Late Glacial climate changes — A case study from eastern Poland
2015
In this study we investigate how climate fluctuation in the Late Glacial period influenced the development of a lake and its catchment located in the East European Plain. We analyzed the sediments of the lake for pollen, subfossil Cladocera, macrofossils and chemical composition. We aimed at disentangling: (1) the climate changes and their limno-ecological responses, (2) temperature dynamics with the use of Cladocera-based transfer function (MJT) and macrofossil-based reconstruction of mean minimum July temperature (MMJT), (3) timing of the response of different proxies to environmental changes. The results of multiproxy analyses explicitly suggest that the main driver for changes in aquati…
Roman Rhine settlement dynamics evidenced by coin distribution in a fluvial environment (Oedenburg, Upper Rhine, France).
2008
International audience; On the basis of archaeological and alluvial records, this paper presents the first spatial analysis of artefacts in relation to the evolution of the Rhine River, at the Gallo-Roman site of Oedenburg, during the first four centuries AD. The dataset consisted of several thousand Roman artefacts found by pedestrian prospecting over the last twenty years, over half of which were coins. This dataset was used together with high-resolution topography and geomagnetic mapping, to reconstruct settlement evolution, both on the terrace and in the floodplain. A comprehensive monetary chart has been compiled for the Oedenburg site, which highlights four major phases of settlement.…
Turia river delta and coastal barrier-lagoon of Valencia (Mediterranean coast of Spain): Geomorphological processes and global climate fluctuations s…
2019
Abstract Extensive drillings and 31 new C-14 datings were used to establish the geomorphological evolution of the Turia river delta and coastal barrier-lagoon system of Valencia (Spain) over the last three millennia. Integration of geomorphological, stratigraphic, malacological, sedimentological and geoarchaeological data enables us to relate river Turia avulsions and alluvial episodes to the development of coastal spits and barriers. Geomorphological changes in the study area may also be associated with global climate events, sea-level fluctuations or anthropogenic periods in the Turia catchment. Six phases may be differentiated: (1) a major early alluviation phase during the Iberian perio…
Biometric and morphometric approaches on Lower Hettangian dinosaur footprints from the Rodez Strait (Aveyron, France).
2012
9 pages; International audience; Along the southern crystalline border of the Rouergue, the detrital Sandstones-variegated Mudstones Formation and the Dolomitic Formation yields numerous dinosaur footprints from the Earliest Hettangian. Among the 25 sites distributed along the 40 km-long transect between Marcillac-Vallon and Saint-Geniez-d'Olt, two of them, Puech de Castres and Le Bouyssou, have yielded abundant ichnites in various well-defined stratigraphic units. The combined analysis of these footprints with biometric and morphometric methods (Fourier analysis) warrants their identification to Grallator, Eubrontes and Dilophosauripus. The dual methodological approach also reveals two new…
Discovery of an Autunian macroflora and lithostratigraphic re-investigation on the western border of the Lodève Permian basin (Mont Sénégra, Hérault,…
2013
11 pages; International audience; Re-investigation of the western edge of the Lodève basin allows reassignment of one sandstone-conglomerate formation previously identified as "terminal Stephanian" to Early Autunian. The existence of two unconformable (Stephanian and Autunian) megasequences, separated by a sedimentary gap, which had been rejected, is thus re-affirmed. The authors also found, less than 20 m above the basal Autunian conglomerate, a macroflora with taxa characteristic of the famous Tuilières flora from a site, located in the eastern part of the basin near Lodève, in the Grey Autunian group. This confirms that the new Mont Sénégra fossiliferous beds belong to the Lower Autunian…
Landscape reconstruction and major flood events of the River Main (Hesse, Germany) in the environs of the Roman fort at Groβkrotzenburg
2020
Abstract Detailed geoarchaeological studies were conducted at the Groβkrotzenburg floodplain (Southern Hesse, Germany) in order to reconstruct the fluvial palaeogeography and search for Roman harbour installations. Another objective was to reconstruct the local flood history based on stratigraphic and geochronological data. Prospection based on electrical resistivity tomography, vibracoring and direct push electrical conductivity logging were carried out to detect and analyze subsurface stratigraphies. Altogether, 6 sediment cores, up to 7 m long, were drilled along transects along and perpendicular to the present course of the River Main. Based on sedimentological and geochemical data, we …
ISOTOPIC TEMPERATURES FROM THE EARLY AND MID-PLIOCENE OF THE US MIDDLE ATLANTIC COASTAL PLAIN, AND THEIR IMPLICATIONS FOR THE CAUSE OF REGIONAL MARIN…
2017
Mean seasonal extreme temperatures on the seafloor calculated from the shell d 18 Oofthescallop Placopecten clintonius from the basal part of the early Pliocene Sunken Meadow Member (Yorktown Formation) in Virginia are very similar to those from the same horizon at the latitude of Cape Hatteras in North Carolina ( ~ 210 km to the south). The lowest and highest temperatures calculated from each shell (using d 18 O seawater ¼þ 0.7 % )givemean values for winter and summer of 8.4 6 1.1 8 C( 6 1 r ) and 18.2 6 0.6 8 CinVirginia,and8.6 6 0.4 8 Cand16.5 6 1.1 8 C in North Carolina (respective median temperatures: 13.3 8 C and 12.6 8 C). Patterns of ontogenetic variation in d 18 O, d 13 C and micro…
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 …
Benthic hydroids (Cnidaria, Hydrozoa) from bathyal and abyssal depths of the Northeast Atlantic held in the moderniDiscovery/iiCollections/i.
2017
The deep-sea benthic hydroid fauna remains poorly known, in part because of less frequent sampling than the shelf fauna, in part owing to the immense study area, and partly also because available samples have been little studied by experts. In order to correct this, deep-sea benthic hydroid material from the modern Discovery Collections has been studied. Samples come from localities in the North-East Atlantic including the Porcupine Seabight, Porcupine Abyssal Plain, Rockall Trough, Rockall Bank, and the Mid-Atlantic Ridge. Sixteen species belonging to 12 families and 16 genera were found. Leptothecata are clearly dominant, being represented by 14 species; the remaining species belong to An…
Mycorrhizal symbiosis primes the accumulation of antiherbivore compounds and enhances herbivore mortality in tomato
2021
Abstract Plant association with arbuscular mycorrhizal fungi (AMF) can increase their ability to overcome multiple stresses, but their impact on plant interactions with herbivorous insects is controversial. Here we show higher mortality of the leaf-chewer Spodoptera exigua when fed on tomato plants colonized by the AMF Funneliformis mosseae, evidencing mycorrhiza-induced resistance. In search of the underlying mechanisms, an untargeted metabolomic analysis through ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS) was performed. The results showed that mycorrhizal symbiosis had a very limited impact on the leaf metabolome in the absence of stress, but significantly m…