[EN]: 42 grasslands of Badajoz and Huelva provinces (Western Spain) were studied recording plant species frequencies with 10 quadrats (20 X 20 cm.) randomly distributed over 2 X 2 m. plots taken under the crown on Quercus rotundifolia trees. Soil samples collected on every plot were analysed for pH, orgainic matter, P, Ca, K and Na. Frequency matrix (80 plant species X 42 plots) was analysed by the method know as "Analyse des Correspondences" (BENZECRI, 1973). The two main components (accounting for about 20% of the overall variation) separate plots into six recognizable groups (grassland types). A preliminary attempt to interpret those groups is made in terms of biotope (soil and substrate) differencies. The two main directions of variation found correspond to an eutrophization gradient (poor acidic versus rich basic soils) and to an erosion gradient (soil erosion versus pedogenesis). Secondary causes of variation are interpreted as due to lithology, climate and management. Further analysis of present data is currently under way.

[ES]: Se han realizado inventarios de frecuencia de herbáceas (diez cuadros de 20 X 20 cm. en inventario) en 42 pastizales de dehesa de Badajoz y norte de Huelva, correspondientes a los principales tipos litológicos. La vegetación se estudió con el análisis de correspondencias. Se detectan seis tipos principales de pastizal que se han interpretado parcialmente con los datos de suelo y sustrato ahora disponibles. En comunicaciones posteriores se completará el análisis con ayuda de otras medidas ahora en realización.

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Peer reviewed