Search results for "Holocene"
showing 10 items of 330 documents
Data from: The relevance of ecological status to ecosystem functions and services in a large boreal lake
2015
1. Environmental conventions aim to protect ecosystem structures and functions to provide goods and services for mankind. The degree of aquatic ecosystem naturalness, or ecological status as it is defined in the Water Framework Directive (WFD) of the European Union, is notionally linked to supplies of ecosystem services. In practice these links have rarely been documented or even investigated and, to justify conservation and management objectives based on the status indicators, it is essential to demonstrate their relationships to ecosystem functions and services. 2. The WFD requires member states to classify their surface waters aiming to achieve good ecological status of water bodies. How…
Data from: Seasonal genetic variation associated with population dynamics of a poecilogonous polychaete worm
2018
Poecilogonous species show variation in developmental mode, with larvae that differ both morphologically and ecologically. The spionid polychaete Pygospio elegans shows variation in developmental mode not only between populations, but also seasonally within populations. We investigated the consequences of this developmental polymorphism on the spatial and seasonal genetic structure of P. elegans at four sites in the Danish Isefjord-Roskilde-Fjord estuary at six time points, from March 2014 until February 2015. We found genetic differentiation between our sampling sites as well as seasonal differentiation at two of the sites. The seasonal genetic shift correlated with the appearance of new s…
Data from: Evidence for an association between post-fledging dispersal and microsatellite multilocus heterozygosity in a large population of greater …
2014
Dispersal can be divided into three stages: departure, transience and settlement. Despite the fact that theoretical studies have emphasized the importance of heterozygosity on dispersal strategies, empirical evidence of its effect on different stages of dispersal is lacking. Here, using multi-event capture-mark-recapture models, we show a negative association between microsatellite multilocus heterozygosity (MLH; 10 loci; n = 1023) and post-fledging dispersal propensity for greater flamingos, Phoenicopterus roseus, born in southern France. We propose that the negative effects of inbreeding depression affects competitive ability and therefore more homozygous individuals are more likely to di…
Data from: Empirical and theoretical study of Atelostomate (Echinoidea, Echinodermata) plate architecture: using graph analysis to reveal structural …
2015
Describing patterns of connectivity among organs is essential for identifying anatomical homologies among taxa. It is also critical for revealing morphogenetic processes and the associated constraints that control the morphological diversification of clades. This is particularly relevant for studies of organisms with skeletons made of discrete elements such as arthropods, vertebrates, and echinoderms. Nonetheless, relatively few studies devoted to morphological disparity have considered connectivity patterns as a level of morphological organization or developed comparative frameworks with proper tools. Here, we analyze connectivity patterns among apical plates in Atelostomata, the most dive…
Beyond Hunting Camps: Early Holocene Occupations in High Cantabrian Mountains (Spain)
1998
En la comunicación se presentan los resultados de las excavaciones en el abrigo de La Calvera (Camaleño, Cantabria) incluyendo un conjunto de nuevas dataciones radiocarbónicas y se hace una reflexión sobre la ocupación de las montañas cantábricas al comienzo del Holoceno. In the communication the results of the excavations in La Calvera rock shelter (Camaleño, Cantabria) are presented, including a set of new radiocarbonic dates and a reflection is made on the occupation of the Cantabrian mountains at the beginning of the Holocene.
Late Quaternary sedimentary evolution of the Castellammare Gulf (North-Western Sicily offshore)
2005
High-resolution seismic stratigraphy has been applied to the interpretation of the stratigraphic architecture of Late Pleistocene and Holocene successions on the continental shelf and upper slope of the Gulf of Castellammare, North-Western Sicily. The Late Quaternary type 1 depositional sequence is bounded by a regional unconformity and it is made up of four systems tracts, developed under fourth order relative sea level fluctuations, after the previous highstand of isotope Stage 5e. Systems tract are located in different parts of the basin, two being confined to the outer shelf and the upper slope, the other developed along the inner shelf. Facies associations, geomorphological elements, a…
First Evidence of Contourite Drifts in the North-Western Sicilian Active Continental Margin (Southern Tyrrhenian Sea)
2021
We present the results of an integrated geomorphological and seismo-stratigraphic study based on high resolution marine data acquired in the north-western Sicilian continental margin. We document for the first time five contourite drifts (marked as EM1a, EM2b, EM2, EM3a, and EM3b), located in the continental slope at depths between ca. 400 and 1500 m. EM1a,b have been interpreted as elongated mounded drifts. EM1a,b are ca. 3 km long, 1.3 km wide, and have a maximum thickness of 36 m in their center that thins northwards, while EM1b is smaller with a thickness up to 24 m. They are internally characterized by mounded seismic packages dominated by continuous and parallel reflectors. EM2 is loc…
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…
Holocene Spatiotemporal Redox Variations in the Southern Baltic Sea
2021
Low oxygen conditions in the modern Baltic Sea are exacerbated by human activities; however, anoxic conditions also prevailed naturally over the Holocene. Few studies have characterized the specific paleoredox conditions (manganous, ferruginous, euxinic) and their frequency in southern Baltic sub-basins during these ancient events. Here, we apply a suite of isotope systems (Fe, Mo, S) and associated elemental proxies (e.g., Fe speciation, Mn) to specifically define water column redox regimes through the Baltic Holocene in a sill-proximal to sill-distal transect (Lille Belt, Bornholm Basin, Landsort Deep) using samples collected during the Integrated Ocean Drilling Program Expedition 347. At…
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 …