4.4. Interpretation of soils maps
The typology of soils and textures thus defined consists of six classes (Figure 5), these nomenclatures according to: Jones and al, 2013; Faraoun, 2013; Benaouda, 1997; IUSS Working Group WRB, 2015; World Reference Base for Soil Resources 2014, update (2015); International soil classification system for naming soils and creating legends for soil maps and World Soil Resources Reports No. 106. FAO, Rome.
The analysis of the maps of soil changes in the study area; show us the dominance of agricultural soils of the type Calcisols, Calcaric Fluvisols. The statistics for 1987 and 2018; show a clear increase reached at most 55% of the total area. In second position Calcaric Cambisols and Rendzic Leptosols, Calcaric Cambisols type soils are very marked by average areas of the order of 16% up to 23%. The humic calcisols, Calcaric Cambisols and Leptosols, Calcaric Cambisols and humic Cambisols (Rubic-Brunic) soils are poorly represented. The most remarkable typologies of textures are : Sandy loam, Loamy sand, Loam,Silty loam and Sandy clay loam.
Figure 5: Maps of the evolution of soils type of the 1987 to 2018 of study area