Search results for "changes"
showing 10 items of 901 documents
Socio-Ecological Contingencies with Climate Changes over the Prehistory in the Mediterranean Iberia
2020
International audience; We conducted palynological, sedimentological, and chronological analyses of a coastal sediment sequence to investigate landscape evolution and agropastoral practices in the Nao Cap region (Spain, Western Mediterranean) since the Holocene. The results allowed for a reconstruction of vegetation, fire, and erosion dynamics in the area, implicating the role of fire in vegetation turnover at 5300 (mesophilous forests replaced by sclerophyllous scrubs) and at 3200 calibrated before present (cal. BP) (more xerophytics). Cereal cultivation was apparent from the beginning of the record, during the Mid-Neolithic period. From 5300 to 3800 cal. BP, long-lasting soil erosion was …
Assessment of channel changes in a Mediterranean ephemeral stream since the early twentieth century. The Rambla de Cervera, eastern Spain
2013
An analysis of morphological changes during the last six decades is presented for a 16.5-km reach of the Rambla de Cervera, a Mediterranean ephemeral stream located in eastern Spain. Channel changes were analysed through a range of techniques, specifically the analysis of aerial photographs with geographical information systems (GIS) and comparison of topographic surveys. The gravel channel underwent a general decline over the study period, losing width (68.5%) and surface area (45.7%). Incision ocurred along the entire study reach at an average depth of 3.5 m. Natural and human-induced factors producing contradictory effects are considered responsible for changes in the Rambla de Cervera
A time series study on the effects of heat on mortality and evaluation of heterogeneity into European and Eastern-Southern Mediterranean cities: resu…
2013
Background: The Mediterranean region is particularly vulnerable to the effect of summer temperature. Within the CIRCE project this time-series study aims to quantify for the first time the effect of summer temperature in Eastern-Southern Mediterranean cities and compared it with European cities around the Mediterranean basin, evaluating city characteristics that explain between-city heterogeneity. Methods: The city-specific effect of maximum apparent temperature (Tappmax) was assessed by Generalized Estimation Equations, assuming a linear threshold model. Then, city-specific estimates were included in a random effect meta-regression analysis to investigate the effect modification by several…
Sea level and climate forcing of the Sr isotope composition of late Miocene Mediterranean marine basins
2014
Sr isotope records from marginal marine basins track the mixing between seawater and local continental runoff, potentially recording the effects of sea level, tectonic, and climate forcing in marine fossils and sediments. Our 110 new Sr-87/Sr-86 analyses on oyster and foraminifera samples from six late Miocene stratigraphic sections in southern Turkey, Crete, and Sicily show that Sr-87/Sr-86 fell below global seawater values in the basins several million years before the Messinian Salinity Crisis, coinciding with tectonic uplift and basin shallowing. 87Sr/86Sr from more centrally located basins (away from the Mediterranean coast) drop below global seawater values only during the Messinian S…
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…
Monsoon onset over Sudan-Sahel: Simulation by the regional scale model MM5.
2006
[1] The Mesoscale Model MM5 is used to study the regional features of the West African Monsoon onset. In order to increase the results, simulations are carried out for eight consecutive seasons (March to September) of the years 1994 to 2001. The results show that the model can reproduce the dynamical features of the monsoon in a reasonably good manner but the seasonal cycle seems enhanced. It is hypothesized that overestimated rainfall amounts could be related to a poor representation of the land surface characteristics. Nevertheless, the mean simulated monsoon onset dates are similar to those find in the CMAP data set. The onset is characterized by an apparent increase in zonal flow that c…
Occurrence of CTX-M Producing Escherichia coli in Soils, Cattle, and Farm Environment in France (Burgundy Region).
2012
Article en open access; International audience; CTX-M [a major type of extended-spectrum beta-lactamase (ESBU] producing Escherichia coli are increasingly involved in human infections worldwide. The aim of this study was to investigate potential reservoirs for such strains: soils, cattle, and farm environment. The prevalence of bla(CTX-M) genes was determined directly from soil DNA extracts obtained from 120 sites in Burgundy (France) using real-time PCR. bla(CTX-M) targets were found in 20% of the DNA extracts tested. Samples of cattle feces (n = 271) were collected from 182 farms in Burgundy. Thirteen ESBL-producing isolates were obtained from 12 farms and further characterized for the pr…
The socio-ecology of zoonotic infections
2011
The resurgence of infectious diseases of zoonotic origin observed in recent years imposes a major morbidity/mortality burden worldwide, and also a major economic burden that extends beyond pure medical costs. The resurgence and epidemiology of zoonoses are complex and dynamic, being influenced by varying parameters that can roughly be categorized as human-related, pathogen-related, and climate/environment-related; however, there is significant interplay between these factors. Human-related factors include modern life trends such as ecotourism, increased exposure through hunting or pet owning, and culinary habits, industrialization sequelae such as farming/food chain intensification, globali…
Transformaciones sociales y territoriales en el incremento de la movilidad por razón de trabajo en Andalucía
2007
Entre 1991 y 2001, tal como se deduce de la información de los censos de población de ambos años, se ha producido un importante incremento de la movilidad en Andalucía por razón de trabajo, especialmente de los desplazamientos entre municipios cercanos. Este trabajo indaga sobre los factores relacionados como causas, y también como consecuencias, con tal incremento. En primer lugar, los cambios en la estructura sectorial, ocupacional y socioeconómica de la población ocupada. En segundo lugar, la ampliación espacial de los mercados locales de trabajo. Y, en tercer lugar, la evolución de la organización espacial de la movilidad, especialmente de la movilidad metropolitana. La conclusión es qu…
Quelques réflexions sur la place de l’axe Saône-Rhône au sein des réseaux d’échanges de l’âge du Bronze. L’exemple des épées à poignée mét…
2018
International audience; Les nombreuses études typologiques portant sur les épées à poignée métallique de l’âge du Bronze ont montré que celles-ci faisaient l’objet d’échanges sur de longues distances, comme en témoigne la diffusion de certaines formes d’un bout à l’autre de l’Europe. L’axe Saône-Rhône devait constituer un axe de passage privilégié pour ces échanges, permettant de faire la jonction entre le monde méditerranéen et les lacs Suisse, avec la vallée du Rhin via le Doubs ou encore avec le monde atlantique via la Loire, l’Yonne et la Seine. Cette situation au carrefour de différentes aires culturelles devait ainsi favoriser les contacts entre groupes à travers l’échange de biens ma…