Abstract. The objectives of this work are: to know the spatial variability of soil physical properties, through the evaluation of the conventional soil map validity for discriminating soil cartographic units with different hydrological behaviour and to characterise their structure or variation model by geostatistical methods. A nested sampling of forty-eight points from two cartographic units mapped at scale 1:50.000 were done. Physical properties were determined at each point. The soils are Entisols and their main use is forestry. The results showed that the principal components are referred to the soil water retention capa-city in function of the bulk density, and the porosity and the internal stoniness. The saturated hydraulic conductivity was one of the properties that discriminated the soil units. The experimental semivariograms were fitted to theoretical models. The fitting of the theoretical semivariograms was better at shorter h distances, and more disperse as h increases. The obtained semivariograms suggest that physical properties have less variability at distances shorter than 300 m.
Keys words: variability, physical properties, principal components, discriminant analysis, semivariograms