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Abstract: A multivariate statistical method (factor analysis of mixed data and hierarchical classification) was used to classify the environmental settings where sorted patterned ground develops in a wet oceanic periglacial area (Skagafjörður, Northern Iceland). A total of 750 periglacial features, distributed over 75 sites, were studied. Nine explanatory variables were assessed by fieldwork and using a digital elevation model, the variables were subdivided into three groups (latitude, topography and soil characteristics) and then integrated into a geographical information system. Furthermore, a correlation between the environmental variables and an intrinsic variable (patterned ground mesh diameter) was determined by a bivariate test. The results show that sorted patterned ground are spread over three homogenous areas, mostly differentiated by altitude, insolation, grain size characteristics and type of drift. In addition, feature diameters differ significantly from one group to another. Finally, it appears that patterned ground diameters are positively correlated with (i) the proportion of clay to medium silt content (r =0.35), (ii) altitude (r =0.51), and especially with (iii) clast length (r =0.97). This strong relationship with clast length is observed in each homogenous patterned ground area at both site and feature scales. [Copyright &y& Elsevier]

Car use generates negative externalities, which are responsible for many health, environmental and economic problems. To tackle this issue, more work is needed to identify better the correlates of car use, especially at the contextual level. In this study, a mobility-focused questionnaire involving 1722 working French adults living in the Paris area (France) was used to explore gender-stratified relationships between residential socioeconomic deprivation and car use as the main transport mode against public transport, after controlling for potential confounders. While the vast majority of similar studies have assumed linear and global statistical relationships, the present work involved a random slope hierarchical generalised additive modelling framework, which revealed both non-linear and territorially-varying relationships. Among women, living in a more deprived neighbourhood was associated with an increase in the odds of reporting car use up to a certain threshold, after which the relationship plateaued, while among men, this relationship is linearly negative. In the most deprived department of the Paris region (Seine-Saint-Denis), living in a more deprived neighbourhood was associated with a lower odds of car use among men while a more complex nonlinear bell-shaped relationship was observed among women. The opposite was found in the wealthiest department (Yvelines), with a negative relationship among women and a U-shaped one among men. In Paris inner city, again a strong opposite trend was distinguished according to sex, with a negative relationship among women. These findings suggest that spatial contexts, characterised by complex interactions between socioeconomic factors, the built environment and the distance to Paris, play the role of moderators in the relationship between residential deprivation and car use. In conclusion, this study reinforces the idea that environment-transport relationships should be understood through local analyses (e.g. random slope multilevel or spatially-varying coefficients models) rather than global ones only, in order to guide specific public policies more effectively. [ABSTRACT FROM AUTHOR]

This cross-sectional study aimed to determine which objective built environmental factors, identified using a virtual neighbourhood audit, were associated with cycling for transport in adults living in five urban regions across Europe. The moderating role of age, gender, socio-economic status and country on these associations was also investigated. Overall, results showed that people living in neighbourhoods with a preponderance of speed limits below 30km/h, many bicycle lanes, with less traffic calming devices, more trees, more litter and many parked cars forming an obstacle on the road were more likely to cycle for transport than people living in areas with lower prevalence of these factors. Evidence was only found for seven out of 56 possible moderators of these associations. These results suggest that reducing speed limits for motorized vehicles and the provision of more bicycle lanes may be effective interventions to promote cycling in Europe. [ABSTRACT FROM AUTHOR]

Abstract: Landform analysis and ground-penetrating radar (GPR) were used to investigate the Thabor rock glacier, in the Northern French Alps. The surface features of the rock glacier were classified and described, with emphasis on massive ice exposures. The retreat of the former Thabor glacier since the Little Ice Age (LIA) was documented through an analysis of historical sources, and recent movements of the rock glacier were inferred from orthophoto-based measurements. Two-dimensional (2-D) models of the radar wave velocity were derived from the raw GPR data, using the numerous diffraction hyperbolae for local determinations of the velocity and kriging interpolation techniques. Subsequently, the profiles were migrated through a 2-D Kirchhoff migration method using the interpolated velocities. The 2-D velocity models exhibit pronounced spatial variations and, in several locations, high values (>0.15mns−1) potentially corresponding to massive ice. On the other hand, while the migrated profiles show numerous layers, the internal stratigraphy of the rock glacier is dominated by a few prominent internal boundaries. The integration of morphology, radar wave velocity, and internal stratigraphy allowed us to identify the main structural units of the rock glacier as well as to explain its genesis: the rock glacier was formed by the imbrication of a massive ice core, originating from the retreat of the former Thabor glacier since the LIA, into pre-existing glacial deposits. [Copyright &y& Elsevier]