**2.3 Methods**

The hierarchical multi-criteria analysis applied in a Geographic Information System for the assessment of soil erosion hazard is increasingly used nowadays. Literature is abundant and has revealed that anthropogenic factors contribute to soil erosion [13–15]. The evaluation of soil sensitivity to erosion in the Menoua intramountain watershed made use of the Hierarchical Analytical Process (PAH) developed by Saaty [16]. Multi-criteria spatial evaluation methods are generally made up of six stages: the entry criteria, the hierarchical structuring of the criteria, the development of binary combinations, the determination of the value and proper vector, the study of consistency of judgment, and finally an aggregation structure, leading to a final relevance map [17].

#### *2.3.1 Elaboration of the erosion sensitivity*

The entry criteria are factors considered included in the decision-making process as having a major influence on soil erosion, and which can be characterized by their respective attributes. This stage aims to characterize the drainage basin from the

topographical, lithological, land use, and climatic perspectives. In this study, the sensitivity of soils to erosion is assessed by applying GIS techniques that take into account the operations of extraction, reclassification, geo-referencing, vectorization, and rasterization based on multi-criteria analysis. These factors are evaluated using the spatial analysis capabilities of ArcMap 10.3. Each evaluation leads to a map representing the entire basin, and its suitability for the factor considered.
