Search results for "assemblages"
showing 10 items of 29 documents
Disentangling scattered charcoal assemblages for palimpsest dissection: Spatial analyses from El Salt Stratigraphic Unit Xb (Eastern Iberia)
2017
International audience; Disentangling scattered charcoal assemblages for palimpsest dissection: spatial analyses from El Salt Stratigraphic unit Xb (Eastern Iberia)
Italian marine reserve effectiveness: does enforcement matter?
2008
Marine protected areas (MPAs) have become popular tools worldwide for ecosystem conservation and fishery management. Fish assemblages can benefit from protection provided by MPAs, especially those that include fully no-take reserves. Fish response to protection can thus be used to evaluate the effectiveness of marine reserves. Most target fish are high-level predators and their overfishing may affect entire communities through trophic cascades. In the Mediterranean rocky sublittoral, marine reserves may allow fish predators of sea urchins to recover and thus whole communities to be restored from coralline barrens to macroalgae. Such direct and indirect reserve effects, however, are likely t…
Marine reserves: size and age do matter
2008
Marine reserves are widely used throughout the world to prevent overfishing and conserve biodiversity, but uncertainties remain about their optimal design. The effects of marine reserves are heterogeneous. Despite theoretical findings, empirical studies have previously found no effect of size on the effectiveness of marine reserves in protecting commercial fish stocks. Using 58 datasets from 19 European marine reserves, we show that reserve size and age do matter: Increasing the size of the no-take zone increases the density of commercial fishes within the reserve compared with outside; whereas the size of the buffer zone has the opposite effect. Moreover, positive effects of marine reserve…
Different key roles of mesoscale oceanographic structures and ocean bathymetry in shaping larval fish distribution pattern: A case study in Sicilian …
2016
Fish larvae data collected in year 2009 were used to examine the effects of particular environmental conditions on the structure of larvalassemblages in two oligotrophic Mediterranean areas (the Southern Tyrrhenian Sea and the Strait of Sicily). For this purpose, relationships with environmental variables (temperature, salinity and fluorescence), zooplankton biomass, water circulation and bathymetry are discussed. Hydrodynamic conditions resulted very differently between two study areas. The Southern Tyrrhenian Sea was characterized by moderate shallow circulation compared to the Strait of Sicily. In this framework, distribution pattern of larval density in the Tyrrhenian Sea was mainly dri…
Structural and functional organization of fish assemblages in a Mediterranean shallow CO2 vent.
2017
Gli effetti dell’acidificazione degli oceani a livello globale hanno richiamato l’attenzione degli scienziati su dei sistemi marini naturali quali i vent superficiali di CO₂. Si tratta di mesocosmi naturali, in quanto su piccole scale spaziali (anche di pochi metri) si osservano marcati gradienti di pH, dove poter testare ipotesi ecologiche dell’acidificazione delle acque marine. Obiettivo della tesi è studiare le risposte della popolazione ittica alla riduzione del pH in vent superficiali mediterranei utilizzando numerosi descrittori, quali la struttura di comunità, l’organizzazione trofica, le caratteristiche e la composizione chimica delle strutture carbonatiche. Inoltre poiché i vent so…
Submersed in the water, buried in the ground: comparative studies on metal assemblages and single finds from french Iron Age non-funerary contexts (V…
2020
Metal hoards are emblematic discoveries of European protohistoric societies and therefore an extremely dynamic research theme. However, even though there are many synthetic studies concerning Bronze Age practices, they are much less frequent concerning Iron Age deposits. In fact, since 1995 (Kurz 1995), no synthetic inventory on this subject had been carried out despite the regular increase in the number of discoveries since the development and multiplication of preventive archaeological excavations. Under these conditions, it seemed important to update the data and this led to the completion of a master's degree on this subject in 2011 (Le Cozanet 2011). Since then, our research hasn‘t cea…
Characterization of the metal artefacts of the two craft-quarters of the roman vicus Bliesbruck (Moselle)
2014
Diese Arbeit ist ein vollständiges Studium der Metallfunde aus den zwei Handwerkervierteln von Bliesbruck (Moselle, Frankreich). Diese Funde stammen aus vierzigjahrelangen Ausgrabungen. Das Korpus besteht aus 450 Kg Metall (Eisen, Kupferlegierungen, weisse Metalle, Gold) wovon 4 200 Objekte und 22 000 Nägel. Eine Objekt- und Funktionsidentifizierung und eine typologische Nägelzahl haben es ermöglicht, die Objektverbindungen wieder zusammenzusetzen und die Daten nach verschiedenen Kriterien einander gegenüberzustellen : Metall, Lage (Viertel und Grundstück), Chronologie und Befundnummertyp. Diese Datenüberfülle und -verschiedenheit ermöglichen das Korpus nach vielartigen geographischen Maβst…
Do large‐scale associations in birds imply biotic interactions or environmental filtering?
2023
Aim There has been a wide interest in the effect of biotic interactions on species' occurrences and abundances at large spatial scales, coupled with a vast development of the statistical methods to study them. Still, evidence for whether the effects of within-trophic-level biotic interactions (e.g. competition and heterospecific attraction) are discernible beyond local scales remains inconsistent. Here, we present a novel hypothesis-testing framework based on joint dynamic species distribution models and functional trait similarity to dissect between environmental filtering and biotic interactions. Location France and Finland. Taxon Birds. Methods We estimated species-to-species association…
Scavenging in the realm of senses: smell and vision drive recruitment at carcasses in Neotropical ecosystems
2022
Social information, acquired through the observation of other individuals, is especially relevant among species belonging to the same guild. The unpredictable and ephemeral nature of carrion implies that social mechanisms may be selected among scavenger species to facilitate carcass location and consumption. Here, we apply a survival-modelling strategy to data obtained through the placement and monitoring of carcasses in the field to analyse possible information transmission cascades within a Neotropical scavenger community. Our study highlights how the use of different senses (smell and sight) within this guild facilitates carcass location through the transmission of social information bet…
The standing of the Southern Côte-d’Or in the evolution of the early Iron Age funeral practices in Burgundy and Franche-Comté
2014
This work is a synthesis of tumuli graves in Burgundy and Franche-Comté from Hallstatt C to La Tene B periods. The objective is to characterize the funeral assemblages in Southern Côte-d’Or as well as the influences and the tendencies that went through this area during the early Iron Age. A set of comparisons shows the particularities of the Southern Côte-d’Or at several levels: the recruitment of the populations, the position and orientation of the deceased, the architecture of the graves and their internal arrangements, the typology and positions of the personals items, the nature and locations of the deposits. These various leads allow reconstituting costumes and mortuary practices, as w…