Aspects macrogéographiques des accidents de la route : essai de comparaison Québec-Belgique

Cet article a pour objectif de démontrer, par comparaison, que la structure spatiale des accidents de la route est indépendante du pays dans lequel le phénomène est mesuré et que seul le facteur d'échelle constitue une différence. Les entités spatiales choisies pour cette démonstration sont le Québec et la Belgique. La structure spatiale des accidents de la route est modélisée et comparée sur la base de trois variables à expliquer et de quatre variables potentiellement explicatives, définissant 52 districts belges et 97 municipalités régionales de comté (MRC) et communautés urbaines (CU) québécoises pour l'année 1991. Les résultats indiquent certaines similitudes quant à la structure spatiale de la densité d'accidents, des taux d'accidents et des taux de mortalité et une différence relative à la structure spatiale de la motorisation. Au Québec comme en Belgique, la densité de population se révèle un bon prédicteur de la densité d'accidents corporels et des taux de mortalité.This paper compares highway crashes in Québec and Belgium in order to understand their broad geographical distribution. The goal is to prove that highway accidents in both places follow an identical pattern of distribution, the only differentiating factor being the dimension (scale) of the territory in which accidents occur. The study uses models in which three dependent variables are explained by four independent ones, in 52 districts of Belgium and 97 regional municipalities of Québec. Results show some similarities in spatial distribution of accident density, accidents rates and mortality rates and some differences in spatial distribution of motor vehicle ownership. In both cases, highway accidents density and mortality rates are related to the density of population

Des Cantons-de-l’Est à l’Estrie

Les auteurs reprennent, dans l'oeuvre de Blanchard, les chapitres sur les Cantons-de-l'Est et en font la mise à jour. La physiographie de même que l'évolution glaciaire et post-glaciaire du milieu physique sont dorénavant mieux connues. L'agriculture se caractérise par l'élevage et la production laitière, le bois demeurant une activité d'appoint. Le développement récent a été influencé par les transports routiers, successeurs du transport ferroviaire. La structure industrielle repose toujours sur les secteurs traditionnels que sont le bois, l'amiante et le textile auxquels se sont ajoutées récemment les industries de micro-technologies. Le tourisme est dorénavant considéré comme l'industrie la plus prometteuse. L'Estrie est-elle encore cette sublime région du Québec que dépeint le dithyrambe de Blanchard ?The authors review and bring up to date the information pertaining to the Eastern Townships in Blanchard's work. With present day knowledge, the physical milieu is more fully understood, particularly the glacial and post-glacial periods. Cattle, pig and milk production are the mainstays of the agriculture industry, while wood cutting is on the decline. Road transportation has supplanted railroads as a main factor in the area's recent development. The main industrial sector is still identified to wood transformation, asbestos mining and textile production; these old industries are being gradually replaced by smaller ones dealing with micro-technologies. Tourism is now an important sector of economic activity. Are the Eastern Townships still that idyllic area of Québec that Blanchard presented in his work

Drivers of Holocene palsa distribution in North America

Palsas and peat plateaus are climatically sensitive landforms in permafrost peatlands. Climate envelope models have previously related palsa/peat plateau distributions in Europe to modern climate, but similar bioclimatic modelling has not been attempted for North America. Recent climate change has rendered many palsas/peat plateaus in this region, and their valuable carbon stores, vulnerable. We fitted a binary logistic regression model to predict palsa/peat plateau presence for North America by relating the distribution of 352 extant landforms to gridded modern climate data. Our model accurately classified 85.3% of grid cells that contain observed palsas/peat plateaus and 77.1% of grid cells without observed palsas/peat plateaus. The model indicates that modern North American palsas/peat plateaus are supported by cold, dry climates with large seasonal temperature ranges and mild growing seasons. We used palaeoclimate simulations from a general circulation model to simulate Holocene distributions of palsas/peat plateaus at 500-year intervals. We constrained these outputs with timings of peat initiation, deglaciation, and postglacial drainage across the continent. Our palaeoclimate simulations indicate that this climate envelope remained stationary in western North America throughout the Holocene, but further east it migrated northwards during 11.5–6.0 ka BP. However, palsa extents in eastern North America were restricted from following this moving climate envelope by late deglaciation, drainage and peat initiation. We validated our Holocene simulations against available palaeoecological records and whilst they agree that permafrost peatlands aggraded earliest in western North America, our simulations contest previous suggestions that late permafrost aggradation in central Canada was climatically-driven