157 research outputs found
Different Types of Children's Independent Mobility in French Brittany
Studies conducted in various countries point out that children's independent mobility has been decreasing over the last decades. This survey was conducted in French Brittany on five sites of varying city size and density. Children mobility is examined through six licences related to outdoor independent movements reported by children aged from 7 to 15 years. From children's declarations, it emerges that there is a clear evolution of independent mobility from primary to secondary school. A cluster analysis permitted to isolate five contrasted types of independent mobility defined by various combinations of licences ranging from a quasi-total dependent mobility to the largest independent mobility. Age is the principal factor significantly associated with each of the five clusters, whereas gender is only associated to one cluster. The type of area and the children's perception of safety in their local area also seem to account for the nature and degree of independent mobility. Overall, these results support the view that a complex array of factors intervenes in the development of children independent mobility, including environmental attributes of the living context such as city size, density and outdoor urban facilities
Children's Independent Mobility: Survey in French Brittany (2011)
The study contributes to an international survey carried out in 16 countries: Australia, Brazil, Denmark, England, Finland, France, Germany, Ireland, Israel, Italy, Japan, Norway, Portugal, South Africa, Sri Lanka, Sweden(Shaw & Watson, 2010). The international survey was initiated by the Political Study Institute of London as an extended geographical replication of the original study of Hillman & al (1990).The general objective of this study is to investigate how children's independent mobility develops between age 7-15. The degree of independent mobility is assessed through the examination of children's statements about six licences related to outside trips without adult supervision. The objective is to provide a detailed picture of the current state of independent mobility in primary and secondary school children of French Brittany (North-West of France). In this respect, the study contributes to an international survey carried out in 16 countries (Shaw & Watson, 2010). The international survey was initiated by the Political Study Institute of London as an extended geographical replication of the original study of Hillman & al (1990). Method A total of 947 children participated in the French survey. Specifically, in primary school 484 children--48,8% girls, 51,2% boys--filled up the questionnaire, age ranging from 6 to 12, mean = 8,79 (sd =1,27). In secondary school 463 young people--49,7% girls, 50,3% boys--responded to the questionnaire, age ranging from 10 to 16, mean = 12,9 (sd =1,29). The survey was conducted in different types of living environment varying in relation to the size and density of the dwelling area. Five types of areas were considered: (1) inner district of a major city, (2) suburban area of a major city, (3) small town, (4) rural market town and (5) rural area. In the French survey, the five types of areas were selected in the same region, namely the district (département) of Ille-et-Vilaine in French Brittany. Therefore, the survey design, which gathered data from different types of areas, was likely to provide a comprehensive picture of the independent mobility of the children living in that particular region. Children's independent mobility was assessed through the examination of six licences: (1) Licence to cross roads alone, (2) Licence to travel to and from school alone, (3) Licence to go on their own to places other than school, (4) Licence to cycle on main roads, (5) Licence to use buses, (6) Licence to go out after dark. Results The comparison of the licences granted by parents to Psc and to Ssc reveals marked difference for all the six licences. This denotes important changes in the parental attitude towards these children's independent mobility within the considered age range. Interestingly the hierarchy of the six licences is almost the same for the two groups. For both groups the licence to cross main roads is the most frequently granted, whereas licence to go out after dark is the least granted. Even in the secondary school, only a few French children are allowed to go out after dark. The analysis of the children's responses also puts forward that independent mobility develop markedly after 11 years when children are in secondary school. Specifically, four of the six licences are held by a large majority of the secondary school children: to go to other places than school on their own, to cross main roads, to use public transport, and to cycle on main roads. However, only one third of these older children declared to go to and from school on their own. This result is probably due to the size of the secondary school catchment areas which were particularly large in four of the five survey areas. Therefore, the distances from the children's homes to secondary school constrained the older children to use the school bus or to be driven by their parents. The primary school children's independent mobility is particularly restricted; four of the six licences examined were hold by less than one third of these children. The licence to go to other places than school is the most frequently mentioned by the 7-to-11-year olds. But only half of primary school children can benefit from such a basic and critical licence that can be seen as a prerequisite to the development of activities independently from adults in the dwelling area. For the other half of the primary school children, this result supports the idea that most out-of-school activities are likely to take place in adult-controlled settings, where children must be accompanied by their parents. Both primary and secondary school children claim to have a particular licence more often than parents declare to grant their children that licence. The differences between children's and parents' responses are particularly obvious as regard to the licence to ride on main roads and, to a lesser degree, the licence to go out after dark. A cluster analysis permitted to isolate five contrasted types of independent mobility defined by various combinations of licences ranging from a quasi-total dependent mobility to the largest independent mobility. Age is the principal factor significantly associated with each of the five clusters, whereas gender is only associated to one cluster. The type of area and the children's perception of safety in their local area also seem to account for the nature and degree of independent mobility. Overall, these results support the view that a complex array of factors intervenes in the development of children independent mobility, including environmental attributes of the living context such as city size, density and outdoor urban facilities
Early Sasanian landscape modification: New geoarchaeological evidence from the Ardashir Pond in southwest Iran (Palace of Ardashir, third century CE)
The Sasanian period (224â651 CE) marked an era of largeâscale urban projects insouthwest Asia, including Iran's semiâarid highlands, with particular efforts to ma-nipulate water bodies. This study presents a recent interdisciplinary investigation ofa springâfed pond at the entrance of the Palace of Ardashir (Firuzabad plain,southwest Iran), part of a recently registered World Heritage site. Historical ac-counts suggest that the entire water system of the plain, including the pond, un-derwent a hydraulic reâorganization at the beginning of the Sasanian period, a factthat has never been investigated geoarchaeologically. A series of sediment coreswere retrieved from the pond to probe its evolution and examine the extent of itslandscape modification. The cores were sedimentologically described andradiocarbonâdated with ageâdepth models established based on 57 AMS (accel-erator mass spectrometry)14C dates to understand the basin's depositional history.The results indicate that (i) Ardashir Pond has existed as part of a larger wetlandcomplex since at least 4500 years ago, (ii) it was substantially enlarged at the be-ginning of the Sasanian era, and (iii) it was abandoned at the end of the Sasanianperiod. The Ardashir Pond is one of the first geoarchaeologically investigated casestudies to demonstrate the Sasanian landscape in the framework of theâIranshahrâsociopolitical concept
The 4.2 ka BP Event in the Mediterranean region: an overview
The Mediterranean region and the Levant have returned some of the clearest evidence of a climatically dry period occurring around 4200 years ago. However, some regional evidence is controversial and contradictory, and issues remain regarding timing, progression, and regional articulation of this event. In this paper, we review the evidence from selected proxies (sea-surface temperature, precipitation, and temperature reconstructed from pollen, ÎŽ18O on speleothems, and ÎŽ18O on lacustrine carbonate) over the Mediterranean Basin to infer possible regional climate patterns during the interval between 4.3 and 3.8âka. The values and limitations of these proxies are discussed, and their potential for furnishing information on seasonality is also explored. Despite the chronological uncertainties, which are the main limitations for disentangling details of the climatic conditions, the data suggest that winter over the Mediterranean involved drier conditions, in addition to already dry summers. However, some exceptions to this prevail - where wetter conditions seem to have persisted - suggesting regional heterogeneity in climate patterns. Temperature data, even if sparse, also suggest a cooling anomaly, even if this is not uniform. The most common paradigm to interpret the precipitation regime in the Mediterranean - a North Atlantic Oscillation-like pattern - is not completely satisfactory to interpret the selected data
New insights on lake sediment DNA from the catchment: importance of taphonomic and analytical issues on the record quality
Over the last decade, an increasing number of studies have used lake sediment DNA to trace past landscape changes, agricultural activities or human presence. However, the processes responsible for lake sediment formation might affect DNA records via taphonomic and analytical processes. It is crucial to understand these processes to ensure reliable interpretations for âpalaeoâ studies. Here, we combined plant and mammal DNA metabarcoding analyses with sedimentological and geochemical analyses from three lake-catchment systems that are characterised by different erosion dynamics. The new insights derived from this approach elucidate and assess issues relating to DNA sources and transfer processes. The sources of eroded materials strongly affect the âcatchment-DNAâ concentration in the sediments. For instance, erosion of upper organic and organo-mineral soil horizons provides a higher amount of plant DNA in lake sediments than deep horizons, bare soils or glacial flours. Moreover, high erosion rates, along with a well-developed hydrographic network, are proposed as factors positively affecting the representation of the catchment flora. The development of open and agricultural landscapes, which favour the erosion, could thus bias the reconstructed landscape trajectory but help the record of these human activities. Regarding domestic animals, pastoral practices and animal behaviour might affect their DNA record because they control the type of source of DNA (âpointâ vs. âdiffuseâ)
Assessing changes in global fire regimes
PAGES, Past Global Changes, is funded by the Swiss Academy of Sciences and the Chinese Academy of Sciences and supported in kind by the University of Bern, Switzerland. Financial support was provided by the U.S. National Science Foundation award numbers 1916565, EAR-2011439, and EAR-2012123. Additional support was provided by the Utah Department of Natural Resources Watershed Restoration Initiative. SSS was supported by Brigham Young University Graduate Studies. MS was supported by National Science Centre, Poland (grant no. 2018/31/B/ST10/02498 and 2021/41/B/ST10/00060). JCA was supported by the European Unionâs Horizon 2020 research and innovation program under the Marie SkĆodowska-Curie grant agreement No 101026211. PF contributed within the framework of the FCT-funded project no. UIDB/04033/2020. SGAF acknowledges support from Trond Mohn Stiftelse (TMS) and University of Bergen for the startup grant âTMS2022STG03â. JMP participation in this research was supported by the Forest Research Centre, a research unit funded by Fundação para a CiĂȘncia e a Tecnologia I.P. (FCT), Portugal (UIDB/00239/2020). A.-LD acknowledge PAGES, PICS CNRS 06484 project, CNRS-INSU, RĂ©gion Nouvelle-Aquitaine, University of Bordeaux DRI and INQUA for workshop support.Background The global human footprint has fundamentally altered wildfire regimes, creating serious consequences for human health, biodiversity, and climate. However, it remains difficult to project how long-term interactions among land use, management, and climate change will affect fire behavior, representing a key knowledge gap for sustainable management. We used expert assessment to combine opinions about past and future fire regimes from 99 wildfire researchers. We asked for quantitative and qualitative assessments of the frequency, type, and implications of fire regime change from the beginning of the Holocene through the year 2300. Results Respondents indicated some direct human influence on wildfire since at leastâ~â12,000 years BP, though natural climate variability remained the dominant driver of fire regime change until around 5,000 years BP, for most study regions. Responses suggested a ten-fold increase in the frequency of fire regime change during the last 250 years compared with the rest of the Holocene, corresponding first with the intensification and extensification of land use and later with anthropogenic climate change. Looking to the future, fire regimes were predicted to intensify, with increases in frequency, severity, and size in all biomes except grassland ecosystems. Fire regimes showed different climate sensitivities across biomes, but the likelihood of fire regime change increased with higher warming scenarios for all biomes. Biodiversity, carbon storage, and other ecosystem services were predicted to decrease for most biomes under higher emission scenarios. We present recommendations for adaptation and mitigation under emerging fire regimes, while recognizing that management options are constrained under higher emission scenarios. Conclusion The influence of humans on wildfire regimes has increased over the last two centuries. The perspective gained from past fires should be considered in land and fire management strategies, but novel fire behavior is likely given the unprecedented human disruption of plant communities, climate, and other factors. Future fire regimes are likely to degrade key ecosystem services, unless climate change is aggressively mitigated. Expert assessment complements empirical data and modeling, providing a broader perspective of fire science to inform decision making and future research priorities.Peer reviewe
(Table 2) Clay-size particles abundances of sediment core PET09P2 from Lake Petit (Southern French Alps)
(Table 6) Detrital fraction and weathering idex of sediment core PET09P2 from Lake Petit (Southern French Alps)
(Table 3) Total organic carbon concentration and Hydrogen/Oxygen indices of sediment core PET09P2 from Lake Petit (Southern French Alps)
(Table 5) Fourier Transformed Infrared Spectroscopy inference for biogenic silica and TOC of sediment core PET09P2 from Lake Petit (Southern French Alps)
- âŠ