Morphological Change Analysis for the Nile River Fourth Reach Using RS/GIS Techniques
Keywords:Morphometric changes, Remote sensing, Geographical information system, Fourth reach.
The Nile is one of the world's great rivers. The Nile River flows 6,853 kilometers long, northward through the tropical climate of eastern Africa and into the Mediterranean Sea. The fourth reach is the longest reach in Egypt, which started from D.S. Assiut Barrage (Kilometer (km) 544.500 D.S. Aswan Dam) to the Delta Barrage (km 954.500 D.S. Aswan Dam). The study reach lies between Beni Suef and ElRodah with length 118.40 km. Morphological variations in this reach of the Nile occurred subsequent to the construction of Aswan High Dam, which influenced on sedimentation and eroded flow. In this research, morphological changes were examined using Remote Sensing (RS) and Geographical Information System (GIS) techniques for a period three years between 1982 and 2019. In moreover, a comparative study was performed among three image classification techniques; onscreen digitizing, maximum likelihood classification and histogram thresholding techniques. The percentage changes between three using techniques are simple as the surface water area along study area in 1982 was 55.75 km2 by onscreen digitizing, 55.74 km2 by maximum likelihood classification, and 55.69 km2 by histogram thresholding technique