Morphometric analysis is a pertinent scientific approach in any hydrological analysis, and it is necessary in the progress and management of drainage basin. Identification of areas at risk of erosion, and the prioritization of 48 sub-watersheds of Inaouene basin, was done by using linear, relief and areal aspects of watershed. The research carried out the use of geographic information system spatial data. The linear aspects include stream number, stream sequence, stream length, and bifurcation ratio, mean length of stream order, stream length ratio, mean stream length ratio, and form factor. The areal aspect includes frequency of stream, drainage density, texture ratio, channel length constant, and overland flow maintenance length. Ultimately, the relief dimensions included relief proportion, relief and ruggedness number. The array of compound (Cp) values computed allow us to set the priority ranks and classify the sub-watershed into three priority ranks groups: low, moderate, and high priority. Such morphometric analyses can be used therefore as a watershed erosion status estimator to prioritize land and water conservation initiatives and natural resources management.

The present work focuses on the prioritization of the wadi Inaouène watershed based on morphometric analysis. The river system was extracted and thirteen sub-catchment basins have been delineated from a DTM using open source software. The following morphometric parameters were calculated for each sub-basin stream length (Lu) and the average length (Lsm), flow length ratio (RL), bifurcation ratio (Rb), medium bifurcation ratio (RBM), drainage density (Dd), drainage texture (T), the flow rate (Fs), elongation rate (Re), circularity ratio (Rc), form factor (Ff), topography and terrain ratio. By combining the values of these parameters we have classified the sub-watersheds in three prioritization categories: high grade (SBV01, SBV04, SBV05, SBV06, SBV11 and SBV12), is subject to a maximum soil erosion, which requires immediate action to prevent possible natural hazards, the Average category (SBV02, SBV03, SBV07, SBV08, SBV09 and SBV10) and low grade (SBV13).

The study of landslides in the Inaouene watershed (northeastern Morocco) provides information on the relationships between landslides and morpho-structural analysis. Landslides affect part of the slopes and slopes of the valley. The configuration of this relationship is controlled by the combination of several predisposing factors. Two localities were studied, located in similar morpho-structural contexts, but characterized by a different lithology. The first determining factor was lithology, in particular the dominance of friable geological formations, especially marls in the locality of Chebabate and limestone soft formations in the locality of Tahla. The second factor was the tectonics, which is well individualized in the limestone of Tahla; in spite of friable lithology of the marls of Chebabate, one manages to disturb traces of the tectonics notably with the level of intercalation of the sandstone benches. Another factor that controls the dissection and the evolution of the landslides is the precipitation by the effect of abundance of the water of impregnation in the formations. The fieldwork is devoted to the measurement of the different faults encountered in the two localities to make the stereographic projection in order to elaborate canvas. The principal objective of this study is to find the relation between the evolution of the risks of erosion and landslide as well as the various factors, who control their spatiotemporal evolution. The results obtained will help managers and decision-makers in the development of watersheds in order to take the necessary steps to reduce the negative impact of this natural hazard on the environment, the population and their property.

The present work reveals the potential of Landsat 8 and ASTER imagery in the lithological discrimination and lineaments extraction in the region of Tiwit (Jbel Saghro). Various remote sensing and image processing techniques were applied to the Landsat 8 and ASTER scenes: False-color composites (RGB 751 & 531), Principal Component Analysis (PCA 653 & 821), Minimum Noise Fraction (MNF 643 & 541), and Independent Component Analysis (ICA 137 & 235). These techniques discriminate the granitic formations (Isk-n-Alla, Mimasmarane, Ibantarn, and Ikniwn), the rhyolitic and ignimbrite formation (Amtattouch, Ouzarzamand Assaka), and other various rock types (aphanitic basalts, sandstones, conglomerates, etc.). The automatic and manual lineaments extraction methods highlight the major lineaments in the study area, trending NE-SW, E-W, and ENE-WSW. The obtained results are consistent with the geologic map of Tiwit. Maximum Likelihood, Spectral Angle Mapper, and Mahalanobis distance classi ers show an overall accuracy of 88%, 56%, and 82.6%, respectively, for Landsat 8. ASTER data show a better result in classi cation with an overall accuracy of 90.6%, 84%, and 88% for the same classi ers.

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