Use of geomatics, Simulating the Impact of Future Land Use and Climate Change on Soil Erosion in the Tigrigra watershed (Azrou region, Middle Atlas, Morocco)

¹ Water Science and Environmental Engineering Team, Moulay Ismail University, Meknes, Morocco.
² ONEE, National Office for Electricity and Drinking Water, Meknes
³ Anassi High School (Annex 2), Ministry of National Education, Meknes
⁴ Department of Geomorphology and Geomatics, Scientific Institute, Mohammed V University, Rabat

Abstract

Soil losses need to be quantified in watersheds to implement erosion protection measures. The main objective of this work is to quantify soil loss in the Tigrigra watershed over the reference period 1985-2020 and two future periods 2050-2070, A Revised Universal Soil Loss Equation (RUSLE) model supported by geographic information systems (GIS) and remote sensing was used. GIS’s model generator can automate various operations of creating thematic layers of model parameters. For future climatic periods (2050-2070), precipitation was produced using a classical statistical downscaling model (SDSM). On the other hand, Automata/Markov models (CA Markov) are used to characterize future land use through modeling in Idrisi software. Over the two periods, the results showed that annual erosivity varies decreases, or increases. The annual soil loss maps showed that 50% of our study area was in the very low class (<5 t/ha/year), while 20% was in the severe class (>80 t/ha/year). These fluctuations are primarily due to the effects of climate change and deforestation/reforestation in the region. This leads to changes in soil erosion due to the important role played by these two factors.