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  • Species distribution models : Spatial autocorrelation and non-stationarity
  • Autocorrélation spatiale ; Biodiversité ; Biogéographie ; Concept ; Distribution spatiale ; Ecologie ; Espèce végétale ; Habitat ; Modèle ; Niche écologique ; Prévision ; Statistique
  • Biodiversity ; Biogeography ; Concept ; Ecological niche ; Ecology ; Forecast ; Habitat ; Model ; Plant species ; Spatial autocorrelation ; Spatial distribution ; Statistics
  • When standard statistical methods such as regression are used to formulate species distribution models, assumptions about the spatial structure of the data and the model parameters are often violated. Autocorrelation and non-stationarity
  • are characteristics of spatial data and models, respectively, and if present and unaccounted for in model development, they can result in poorly specified models as well as inappropriate spatial inference and prediction. While these spatial issues are addressed here
  • in an ecological context using species distribution models, they are broadly relevant to any statistical modeling applications using spatial data.
  • 2012
  • Continuous-time modeling with spatial dependence
  • Allemagne ; Calcul matriciel ; Chômage ; Dépendance spatiale ; Economie spatiale ; Marché local du travail ; Modèle ; Population active
  • Germany ; Local labour market ; Matrix analysis ; Model ; Spatial dependence ; Spatial economy ; Unemployment ; Working population
  • The article introduces spatial dependence in a continuous-time modeling framework. The structural equation model with spatial dependence is the first dynamic one. A simple regional labor market model for Germany is illustrated, comprising changes
  • 2012
  • Regional coverage maximization : a new model to account implicitly for complementary coverage
  • Choix du site ; Distribution de points ; Equipement ; Localisation ; Modèle ; Organisation de l'espace ; Représentation de l'espace
  • Distribution of points ; Facilities ; Location ; Location choice ; Model ; Spatial organization ; Spatial representation
  • The article revisits model development for the problem of regional coverage maximization and proposes a new formulation where coverage of spatial demand is implicitly modeled. Model testing is conducted through an application to warning siren siting
  • 2012
  • Modelling soil erosion with a downscaled landscape evolution model
  • Australie ; Bassin-versant ; Erosion des sols ; Géomorphodynamique ; Modèle ; Modèle numérique ; Modèle numérique de terrain ; Northern Territory ; Topographie ; Vitesse d'érosion
  • Australia ; Digital elevation model ; Earth surface processes ; Erosion rate ; Model ; Northern Territory ; Numerical model ; Soil erosion ; Topography ; Watershed
  • This paper applies a landscape evolution model (LEM) for the first time at time and space scales where soil erosion models have largely been used. It tests the ability of the LEM (the CAESAR model) to predict soil erosion on a 30 m experimental plot
  • and bedload yields from CAESAR show a close correspondence in both volume and timing of field measured data. The model also predicts, at decadal scales, sediment loads close to that of field measured data. Findings indicate that the small-scale drainage
  • 2012
  • Bassin-versant ; Cours d'eau ; Erosion des sols ; Erosion hydrique ; Modèle ; Modèle mathématique ; Sédimentation ; Tchèque république ; Černičí
  • Czech Republic ; Mathematical model ; Model ; Sedimentation ; Soil erosion ; Stream ; Water erosion ; Watershed
  • The most widespread method of measuring soil erosion processes using mathematical models, USLE, and its modifications have been used as the basis for new erosion models. Two such models, USPED and WaTEM/SEDEM, have been utilized to study erosion
  • and deposition processes in the experimental rural catchment of Černičí. River sediment transport is also calculated using the WaTEM/ SEDEM model. The results are discussed with results from USLE and a field survey. - (EN)
  • 2012
  • A new method of adaptive zoning for spatial interaction models
  • Agrégation ; Analyse spatiale ; England ; Interaction spatiale ; Migration alternante ; Modèle ; Modèle de gravité ; Méthodologie ; Système spatial ; Zonage
  • Aggregation ; Commuting ; England ; Gravity model ; Methodology ; Model ; Spatial analysis ; Spatial interaction ; Spatial system ; Zoning
  • Introduction d'un type nouveau de système à zonage discret, afin de réduire le temps d'estimation et d'application des modèles d'interaction spatiale tout en maintenant leur précision. Le nouveau système stipule que la taille appropriée des zones de
  • destination dépend de la distance aux zones d'origine. On définit une carte des zones spécifiques pour chaque zone d'origine. Chaque zone devient le foyer de sa propre carte. Formulation théorique et test avec un modèle des migrations alternantes en Angleterre.
  • 2012
  • A permafrost probability model for the Southern Yukon and Northern British Columbia, Canada
  • British Columbia ; Canada ; Distribution spatiale ; Modèle ; Modèle numérique de terrain ; Montagne ; Northwest Territories ; Pergélisol ; Périglaciaire ; Rayonnement solaire ; Température du sol ; Végétation ; Yukon
  • British Columbia ; Canada ; Digital elevation model ; Model ; Mountain ; Northwest Territories ; Periglacial features ; Permafrost ; Soil temperature ; Solar radiation ; Spatial distribution ; Vegetation ; Yukon
  • The high-resolution probability model for the southern Yukon and northern British Columbia presented here (regional model) is a combination of 7 local empirical-statistical models, each developed from basal temperature of snow measurements in winter
  • and ground-truthing of frozen-ground presence in summer. The models were blended using a distance-decay power approach to generate a map of permafrost probability over an area of almost 500 000 km2 between 59°N and 65°N. The result is broadly similar
  • to previous permafrost maps. There are notable differences in detail, however, because the main predictive variable used in the local models is equivalent elevation, which incorporates the effects of gentle or inverted surface lapse rates in the forest zone
  • . The results of the modelling can be presented on paper using traditional classifications into permafrost zones but given the level of detail, they will be more useful as an interactive online map.
  • 2012
  • Élaboration d'un modèle pour le développement de la conscience environnementale et des comportements respectueux de l'environnement
  • Comportement ; Développement durable ; Environnement ; Modèle ; Protection de l'environnement ; Responsabilisation ; Slovénie
  • Behaviour ; Empowerment ; Environment ; Environmental conservation ; Model ; Slovenia ; Sustainable development
  • The AA. regard people’s mentality, awareness and behaviour as the most critical factors in forming and solving this problem. Factors, which influence environmental behaviour, were studied on the basis of behavioural models and their reciprocal
  • comparison. A synthesis model of developing awareness and environmentally friendly behaviour and in addition plan of encouraging environmentally friendly behaviour was formed. - (IKR)
  • 2012
  • Modelling sediment dynamics due to hillslope–river interactions : incorporating fluvial behaviour in landscape evolution model LAPSUS
  • Bassin-versant ; Débit ; Erodabilité ; Espagne ; Géomorphodynamique ; Modèle ; Modèle numérique de terrain ; Murcia ; Simulation ; Transport sédimentaire
  • Digital elevation model ; Discharge ; Earth surface processes ; Erodibility ; Model ; Murcia ; Sediment transport ; Simulation ; Spain ; Watershed
  • LEM LAPSUS is a relatively simple cellular model operating on timescales of centuries to millennia and using annual timesteps that has had a hillslope focus. In this paper, the AA. developed, tested and demonstrate the ability of LEM LAPSUS
  • to simulate sediment dynamics for coupled hillslope-river systems without adding new process equations. The model should be able to reproduce alternating aggradation and incision in the floodplains of catchments, depending on simulated conditions. Testing
  • was done using an artificial digital elevation model (DEM) and a demonstration of the ability for fluvial simulation was performed for a real landscape (Torrealvilla catchment in the Guadalentín Basin, Murcia Province, southeast Spain).
  • 2012
  • Représentation de la pluie dans les modèles régionaux de climat et application à l'estimation des rendements du mil au Sénégal
  • Agroclimatologie ; Années 1991-2007 ; Biais statistique ; Céréale ; Mil ; Modèle ; Modèle climatique régional ; Pluviométrie ; Précipitation ; Rendement agricole ; Simulation ; Sénégal
  • Agroclimatology ; Cereal ; Crop yield ; Millet ; Model ; Pluviometry ; Precipitation ; Senegal ; Simulation ; Statistical bias
  • Il existe une grande dispersion dans la représentation de la pluviométrie d'un modèle régional à l'autre (voire pour un même modèle régional avec deux jeux de paramètres différents), tant à l'échelle saisonnière qu'à l'échelle intrasaisonnière. Ces
  • 2012
  • Analyse spatiale ; Echelle ; France ; Géoprospective ; Modèle ; Modélisation ; Prospective ; Scénario ; Simulation
  • France ; Geo-prospective ; Model ; Modelling ; Prospective study ; Scale ; Scenario ; Simulation ; Spatial analysis
  • L'A. analyse comment la modélisation d'accompagnement fait de la géoprospective et sous quelle forme particulière. La réflexion porte sur la démarche de modélisation : explication du modèle du domaine, co-construction du modèle conceptuel
  • , définition de scénarios et simulation exploratoire. Niveaux de réalisme des modèles spatialisés, prise en compte de différentes échelles d'espace et de temps, place du modélisateur et des modèles proposés comme objets intermédiaires entre les acteurs et leur
  • 2012
  • Contribution to regional division of Slovakia based on the application of the Reilly’s model
  • Analyse régionale ; Division administrative ; Géographie régionale ; Modèle de Reilly ; Modèle de gravité ; Région urbaine ; Régionalisation ; Slovaquie
  • Administrative unit ; Gravity model ; Regional analysis ; Regional geography ; Regionalization ; Slovak Republic ; Urban region
  • The objective of the article is an application of three versions of the Reilly’s model in a regional division of Slovakia at two levels: from the point of view of potential natural gravity towards regional centres, and from the aspect
  • of an alternative proposal of administrative division of Slovakia at the regional level. In this contribution the geometric version of the Reilly’s model serves only as a complementary tool for an assessment of a regional organisation of Slovakia. A crucial part
  • 2012
  • Testing the physical model concept by soil loss data measured in Sicily
  • Analyse quantitative ; Erosion des sols ; Italie ; Modèle ; Parcelle expérimentale ; Prévision ; Sicilia ; Sol cultivé
  • Cultivated land ; Experiment plot ; Forecast ; Italy ; Model ; Quantitative analysis ; Sicilia ; Soil erosion
  • In this paper the physical model concept developed in USA was tested by using soil loss data collected on plots of different length at the experimental station of Sparacia, in Sicily (South Italy). This investigation supported the conclusions that i
  • ) a coefficient of determination between measured and predicted soil loss values of 0.77 has to be considered as the best-case prediction scenario and ii) an uncalibrated deterministic erosion model would not give more accurate results than those obtained
  • by a replicated plot measurement. This calculation is useful since it allows to quantitatively establish the maximum gap that has to be covered by an alternative simulation model to obtain the realistically best estimate of plot soil loss at the event temporal
  • 2012
  • Auto-organisation ; Conditions initiales ; Cycle géomorphologique ; Etude comparée ; Fluviatile ; Géomorphodynamique ; Géomorphologie littorale ; Modèle ; Modèle numérique ; Paysage ; Topographie ; Vallée
  • Coastal geomorphology ; Comparative study ; Earth surface processes ; Fluvial processes ; Geomorphic cycle ; Initial conditions ; Landscape ; Model ; Numerical model ; Self-organizing behaviour ; Topography ; Valley
  • of cyclic steps in steep, sandy beds. In this section, they briefly describe the dynamics of these systems and the models used to conduct the numerical experiments. The results highlight the importance to consider the influence of initial conditions when
  • comparing models with natural topography, estimating the uncertainty of model predictions, and studying how landscapes respond to disturbances.
  • 2012
  • Adaptation behaviours across ecosystems under global warming : a spatial micro-economic model of the rural economy in South America
  • Adaptation ; Amérique latine ; Changement climatique ; Economie rurale ; Ecosystème ; Elevage ; Modèle ; Modèle micro-économétrique ; Récolte ; Scénario ; Stratégie économique ; Utilisation agricole du sol
  • Adaptation ; Agricultural land use ; Climatic change ; Crop ; Econometry ; Economic strategy ; Ecosystem ; Latin America ; Livestock farming ; Model ; Rural economy ; Scenario
  • The paper develops a spatial rural economy model of adaptation to rural change that accounts for a multitude of rural enterprises across a diversity of ecosystems in South America using household surveys. Adoptions of crops, livestock, forests
  • and both specialized and diversified enterprises are modeled. Livestock, forests, and a diversification into crops, livestock, and forests are key adaptation strategies. Adaptation behaviours are closely tied with ecosystem changes under global warming.
  • 2012
  • The estimation of estuary dimensions using a simplified form model and the exogenous controls
  • Estuaire ; Géomorphologie ; Hydrodynamique ; Marée ; Modèle ; Royaume-Uni ; Sédimentologie ; Vague
  • Estuary ; Geomorphology ; Hydrodynamics ; Model ; Sedimentology ; Tide ; United Kingdom ; Wave
  • considering just tidal flow, the model was found to provide an adequate representation, however, the inclusion of wave action was found to significantly improve the predictive power of the model. The exogenous parameters therefore provide a basis
  • 2012
  • Introducing new measures of accuracy for land-use/cover change modeling
  • Concept ; Couverture végétale ; Erreur ; Indice ; Modèle ; Méthodologie ; Utilisation du sol
  • Concept ; Error ; Index ; Land use ; Methodology ; Model ; Plant cover
  • field of land-use/cover (LUC) change modeling. Firstly, the paper reviews existing validation parameters and presents a conceptual analysis of these parameters, including the 3 proposed new indices. And secondly, the paper discusses the potentials
  • of these indices relative to the current important issues of LUC change modeling accuracy assessment.
  • 2012
  • Endogeneité et autocorrélation spatiale : quelle utilité pour le modèle de Durbin ?
  • Autocorrélation spatiale ; Biais statistique ; Economie spatiale ; Endogénéité ; Erreur ; Modèle économétrique ; Méthode de Monte Carlo
  • Econometric model ; Error ; Monte Carlo analysis ; Spatial autocorrelation ; Spatial economy ; Statistical bias
  • un modèle spatial de Durbin, dans lequel figurent à la fois une variable spatiale endogène décalée ainsi que les décalages spatiaux des variables exogènes. Le biais des estimateurs obtenus sur la base de ce modèle restent relativement fiables dans les
  • 2012
  • Growth and disparities in Europe : insights from a spatial growth model
  • Croissance économique ; Différenciation spatiale ; Disparités régionales ; Economie régionale ; Econométrie ; Europe ; Modèle de croissance ; Production ; Ressources humaines
  • Econometry ; Economic growth ; Europe ; Growth model ; Human capital ; Production ; Regional disparities ; Regional economy ; Spatial differentiation
  • Modèle de croissance spatiale néoclassique dans un système d'économies régionales. La dynamique du modèle est accaparée par une approximation selon Taylor, qui fournit une spécification économétrique testable appliquée aux régions européennes de
  • 2012
  • A new method to determine the upper boundary condition for a permafrost thermal model : an example from the Qinghai-Tibet Plateau
  • Analyse de régression ; Changement climatique ; Chine ; Climat régional ; Haute montagne ; Infrastructure ; Modèle ; Pergélisol ; Plateau ; Périglaciaire ; Qinghai ; Régime thermique ; Température de l'air ; Température du sol ; Tibet ; Utilisation
  • Air temperature ; China ; Climatic change ; Cold area ; High mountain ; Infrastructure ; Land use ; Model ; Periglacial features ; Permafrost ; Plateau ; Qinghai ; Regional climate ; Regression analysis ; Soil temperature ; Thermal regime ; Tibet
  • The AA. report on an approach designed to predict time series of air, ground surface and shallow ground temperatures at a spatial scale for engineering design of a railway or highway project. The approach uses a regional-scale atmospheric model
  • to downscale global climate model output, and then stepwise multiple regression to develop an equation that provides a best-fit prediction of site-specific observational data using bilinearly interpolated output from the atmospheric model. This approach bridges
  • the scale difference between atmospheric climate models and permafrost thermal models, and allows for a wider range of factors to be used in predicting the thermal boundary condition. For a research site located in Beiluhe, close to the Qinghai-Tibet Railway
  • , a comparison of model predictions with observational data not used in the construction of the model shows that this method can be used with a high degree of accuracy to determine the upper boundary condition for a permafrost thermal model.
  • 2012