Landslide susceptibility mapping using GIS Matrix Method and Frequency Ratio, application in the marly context of Moulay Yacoub Region, Morocco

Abstract

In the recent decades, the growth of population, man-made facilities, infrastructures, and lifelines at the expense of landslides-prone areas has been responsible for an exponential increase in human and economic losses in many parts of the world. In the Moulay Yacoub region, where marly hills dominate, the interaction of the semi-urban and rural socioeconomic development and landslides significantly increases, which urges identifying and prioritizing areas of risk in order to maximize harm reduction and to avoid the disastrous outcomes as is the case of Moulay Yacoub town. This paper aims to develop a landslide susceptibility map in a highly affected sector of the province, where no previous landslide data have been produced, and to find the most predisposing parameters. This goal is attained using two robust methods for landslide susceptibility mapping, the Frequency Ratio and the GIS Matrix Method. Before that, the correlation of 11 predisposing factors was tested. The results show that the anthropogenic factors, particularly the agricultural practices, were highly involved, and the field investigations proved that cereal farming slopes are the most affected. The success rate was about 0.75 (75%) for both models showing good quality results for the two susceptibility maps. Therefore, the two models could be efficiently used, and the new agricultural projects located in landslide-prone areas of the province must include such reliable methods of landslide hazard analysis to minimize the risk, which would put human lives, ecosystems, food production, and infrastructure in threat.