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PORTAIL D'INFORMATION GÉOGRAPHIQUE

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  • français ERAMET, son extraction entraine d’un côté la métamorphose du paysage et de l’autre côté la pollution physique voire chimique des écosystèmes adjacents. À propos de l’uranium, cette ancienne exploitation de Comuf, filiale du groupe Areva (hérité de
  • COGEMA), est à l’origine d’un passif environnemental qui compose avec la présence anormalement élevée de la radioactivité et la transformation du paysage originel. En fin de compte, ces deux activités révèlent la dualité société/nature au bout de laquelle
  • 2014
  • A study of the contribution of mass elevation effect to the altitudinal distribution of timberline in the Northern Hemisphere
  • This paper collects 516 data sites of timberline, and takes latitude, continentality and mass elevation effect (MEE) as independent variables and timberline elevation as dependent variable to develop a ternary linear regression model. Continentality
  • is calculated using the meteorological data released by WorldClim and mountain base elevation (as a proxy of mass elevation effect) is extracted on the basis of SRTM 90-meter resolution elevation data. The results show that MEE is simply the primary factor
  • contributing to the elevation distribution of timberline on the continental and hemispherical scales. The contribution rate of MEE to timberline altitude differs in North America, eastern Eurasia and in the western Eurasia, but it is usually very high.
  • 2014
  • Identifying the impact on land prices of replacing at-grade or elevated railways with underground subways in the Seoul Metropolitan Area
  • The present study focuses on laying the empirical groundwork for the Seoul metropolitan government to replace at-grade or elevated railways with underground subways. Statistical tests have verified a significant difference in several variables
  • according to whether a station area belongs to at-grade (or elevated) railways or underground subways. As a result of the regression model, it is confirmed that the land price of areas along at-grade or elevated railways are much less than those along
  • 2014
  • Coal ; Digital elevation model ; Geomorphology ; Germany ; Human impact ; Impact ; Mining activity ; North Rhine Westfalia ; Ruhr ; Subsidence
  • This paper presents spatial differences in ground level changes in the Ruhr District due to large-scale coal extraction over the past 100 years. Elevation data on historical maps from 1892 was digitised with the help of a Geographic Information
  • System and the interpolated historical surface was intersected with a current Digital Elevation Model, in order to calculate the differences in elevation. As a result, the highest values of subsidence, amounting to more than 25 m, were observed within
  • the coalfields of the former coal mine Zollverein. Two examples from the cities of Essen and Dortmund analysed in detail reveal that not only depressions but also elevation features are affected by mining subsidence. These kinds of surface transformations
  • 2014
  • Automatic clod detection and boundary estimation from Digital Elevation Model images using different approaches
  • Aggregate ; Digital elevation model ; Methodology ; Micro-topography ; Soil ; Soil properties
  • The aim of this study is to propose and discuss some methods dedicated to the automatic localization of clods (or big aggregates) on Digital Elevation Model images of soil. Two new image processing methods are introduced. The first one deals
  • 2014
  • Agriculture ; Crop yield ; Czech Republic ; Digital elevation model ; Model ; Slope evolution ; Topography
  • This paper deals with the prospects of modelling topographic features – digital elevation models and slope models for an experimental plot with an area of 11.5 hectares. The basis for the creation of these models is formed by data from various
  • 2014
  • Recent warming amplification over high elevation regions across the globe
  • 2014
  • Clay mineral ; Coastal plain ; Digital elevation model ; Grain size distribution ; Nigeria ; Pedogenesis ; Slope gradient ; Soil water
  • , field capacity water content (FWC), permanent wilting point (PWP), and available water content (AWC) were determined. Elevation, slope, aspect, curvatures, flow direction and hill shade, compound topographic index (CTI) and stream power index (SPI) were
  • derived from a digital elevation model. The data were analyzed using correlation, principal component and stepwise multiple regression. the results indicated that : Particle size fractions are major determinants of variability; Overland flow and ordering
  • 2014
  • Digital elevation models derived from airborne laser scanning point clouds : appropriate spatial resolutions for multi-temporal characterization and quantification of geomorphological processes
  • Alps (The) ; Austria ; Digital elevation model ; Error ; Geomorphometry ; High mountain ; LiDAR ; Mountain ; Quantitative analysis ; Roughness ; Slope gradient ; Tirol
  • 2014
  • Avec 1038 icebergs ayant franchi le 48ème parallèle et, donc, ayant pénétré dans des zones largement fréquentées par les navires, le risque de collision était élevé en avril 1912, mais il n'avait rien d'exceptionnel si on le compare aux années
  • 2014
  • The A. examined the relative influence of 8 spatial characteristics on native plant diversity in 22 volcanic high islands of eastern Polynesia : island area, highest elevation, distance to the nearest continent, distance to the nearest archipelago
  • with the island area and highest elevation of the islands. Contemporary cyclones were an important predictor of indigenous plant diversity in the remote islands surveyed. In the high islands surveyed, isolation did not appear as a significant predictor of native
  • 2014
  • of large volcanic eruptions since 1750 according to their geographic latitudes, their elevations, and the years and months in which they occurred. The results show that most large volcanic eruptions were located around the margins of the Pacific Ocean
  • and the islands of Sumatra and Java, especially in the equatorial regions (10°N-10°S). Large volcanic eruptions were concentrated at 1000–2000 m elevations and in the months of January and April. Large volcanic eruptions have interdecadal fluctuations, including
  • 2014
  • Alps (The) ; Debris flow ; Digital elevation model ; Friuli-Venezia Giulia ; Italy ; Methodology ; Monitoring ; Mountain ; Terrestrial laser scanning ; Vegetation ; Watershed
  • dynamics. For these areas, DEM of Differences (DoDs) with a 0.2 m spatial resolution allowed the assessment of elevation uncertainty as spatially variable by applying the fuzzy inference system (FIS). A new index, named Vegetation Noise, that takes
  • 2014
  • by the use of elevation, aspect, slope and vegetation as variables in the calculation of the SWE. Elevation and vegetation show a significant correlation with the SWE in the study area. The multiple regression gave best results for snow accumulation period
  • 2014
  • extents and particularly the occurrence of large landslides on the dip slope flank, the flank averaged beryllium-10 (10Be)-derived denudation rates are very similar. The denudation rates reveal a positive correlation to mean basin elevation
  • , the denudation rates have a strong orographic control through elevation dependent mean annual temperature and precipitation.
  • 2014
  • Data processing ; Digital elevation model ; Earth surface processes ; Erosion rate ; Experimental catchment ; Gully erosion ; Methodology ; Photography ; Spain ; Terrestrial laser scanning ; Watershed
  • ). Results of this analysis showed centimetre-level accuracies with average distances between the 2 point clouds for the 5 headcuts ranging from 0.009 m to 0.025 m. Then, using a Digital Elevation Model of Differences approach (DoDs) the volume of soil loss
  • 2014
  • Conditions de formation de la quantité d’eau extrêmement élevée des cours d’eau de Primorié durant la période d’automne à hiver 2012
  • Analyse des conditions synoptiques et hydrologiques qui ont contribué à la formation de la quantité d’eau très élevée dans les cours d’eau du kraï de Primorié en automne 2012. Les AA. étudient la circulation atmosphérique, les précipitations, le
  • 2014
  • Comparative study ; Digital elevation model ; Error ; Geodesy ; Glacier ; Glacier fluctuation ; Glacier mass balance ; LiDAR ; Methodology ; Switzerland ; Terrestrial laser scanning ; Valais
  • from different geodetic methods and spatial resolutions. The evaluation showed that, although the digital elevation models were perfectly co-registered, systematic and random method- and scale-dependent errors still occurred. These errors have an impact
  • 2014
  • Arctic Region ; Climatic change ; Digital elevation model ; Glacial features ; Glacier retreat ; Moraine ; Photointerpretation ; Svalbard
  • Ragnarbreen is a small glacier located in the central part of Spitsbergen Island. Glacier recession and landforms' development in the foreland of Ragnarbreen are quantified using time-series orthophotos and digital elevation models, which were
  • 2014
  • Comparative study ; Digital elevation model ; Erosion rate ; LiDAR ; Model ; Norway ; Soil erosion ; Water erosion ; Watershed
  • on effects of grid cell size and time resolution. The grid cell size of the maps was easily adapted by using digital elevation models (DEM) obtained from airborne light detection and ranging (LIDAR) data. Furthermore the predicted erosion patterns were
  • 2014