Study of the Solonchaks of Northern Algeria by a Geographic Information System (GIS)

Abstract

The present study consists of a valorization of a pedological database allowing to determine the Solonchaks in the north of Algeria according to the World Reference Base (WRB) classification. We studied the constituents of these Solonchaks by making different thematic maps, for this purpose a geographic information system (GIS) was created. Profiles meeting the definition of Solonchaks will be classified, spatialized in northern Algeria and grouped into reference soils and the creation of different thematic maps. The main results revealed that the Solonchaks of northern Algeria are provided with calcium carbonate (10 < CaCO3 (%) < 60) and poorly provided with gypsum with an average of 2.5% gypsum. They are also characterized by very high salinity (15 < EC (dS/m) < 40.9) and relatively high sodicity percentage of exchangeable sodium (ESP) > 15%). Statistical analysis revealed that the correlation between the EC-ESP couple is highly significant (r = 0.62; p < 0.01). Similarly, the correlation between the EC and the Ca++ of the adsorbent complex is negative and significant (r = -0.34; p < 0.05). The exploitation of the database made it possible to extract 45 profiles corresponding to the Solonchaks. The classification of these profiles revealed 13 references of Solonchaks distributed in the north of Algeria.