Document Type : Research Article
Associate Professor,, Department of Nature Engineering, Faculty of Natural Resources and Environment, Science and Research Branch, Islamic Azad University, Tehran, Iran
PhD candidate, Department of Nature Engineering, Faculty of Natural Resources and Environment, Science and Research Branch, Islamic Azad University, Tehran, Iran
Department of Reclamation of Arid and Mountainous Regions, Faculty of Natural Resources, University of Tehran, Karaj, Iran.
There are two main components of erosion: Erosion and Erodibility. Erosion is primarily caused by precipitation and runoff, while erodibility results from the type of the formations at the catchment scale, which is the subject of research in the study area. The objective of this study was to investigate the relationship between geologic units and erosion intensity. Initially, two models of mpsiac and Fargas were used to study erosion intensity. The Fargas model was presented based on the theoretical principles of two erosion and the erodibility factors, while the mpsiac model was based on 9 factors, including surface geology, soil, climate, runoff, topology, land cover, land use, the current status of land erosion (upstream, river basins). Accordingly, two models were used in the current study to determine the erosion intensity of the formations. According to the mpsiac model, 79% of the basin surface had high erosion intensity and 21% had very high erosion intensity; while according to the Fargas model, 0.3% had moderate erosion intensity, 10% had high erosion intensity, and the remaining 4.7% and 85% were characterized with severe erosion and very severe erosion. In addition, in both models, 18% corresponded to very high erosion intensity (very severe), while 7.2% had high erosion intensity. In the Fargas model, E1t1, E1t2, E2ig3, Q2f, Qt1, and Qt2 had very strong erosion intensity, whereas, in the mpsiac model, E1t1, Qt1, and Qt2 had high erosion intensity on their surfaces. One explanation for this phenomenon could be the erodibility of the formations. Most of E1t2 and Q2t is highly eroded, which contributes to a large amount of drainage in addition to the erodibility of the formations.