Correlations between pedological parameters in relation to lithology and soil type in Almería (SE Spain)

Abstract South-eastern Spain can be considered as a model of desertification in the Mediterranean environment. The desertification intensity varies according to two different geomorphological areas: glacis and badlands. The modal soil of the glacis area is calcic Luvisol, for which the severity of degradation depends on the degree of aridity and human activities, which give rise to the following degradation series: calcic Luvisol – luvic Calcisol – haplic, petric or aridic Calcisol. The badland area is more desertified than the glacis area. The modal soils in the badland area depend exclusively on the parent material: aridic Arenosols on sand; eutric, calcaric or gypsiric Regosols on silt and calcilutite; aric Gypsisols on gypsum; and aric Solonchaks on parent material rich in halite. Luvisols, Gypsisols and Solonchaks can be considered relict paleosols that developed in a wetter climate than the prevailing arid conditions that make clay illuviation or the formation of gypsic or salic horizons impossible. Soil quality reduction is shown by creating a database for soils’ physical and chemical properties, ranging in classes that facilitate the use of these properties as an effective tool for decision making with regard to desertification.