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.
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
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
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
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)
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.
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.
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)
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).
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.
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.
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
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
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
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
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.
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
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
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
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.