Abstract

• The Ayeyarwady River is the main artery and an important source of multipurpose. Compared to its historical condition, the Ayeyarwady River's morphology has undergone significant changes as a result of erosion and deposition. These natural processes have shaped the river's landscape, altering its course and creating new land formations along its banks. Of all river sections, the Ayeyarwady River from Chauk to Magway area is the most affected by human impacts. Remote Sensing (RS) and Geographical Information Systems (GIS) are widely used for change detection in rivers caused by erosion and deposition. Digital image processing techniques and GIS analysis capabilities are used for detecting temporal variations in erosion and deposition characteristics of the Ayeyarwady River from Chauk to Magway areas during the years 1990, 2011, and 2022. The study aims to assess spatial variation in the Ayeyarwady River in the periods 1991, 2011, and 2022. Landsat satellite images for the years 1990, 2011, and 2022 were processed to investigate the erosion and deposition areas, patterns, and sedimentation conditions of the Ayeyarwady River. In the study, NDWI and MNDWI were used to create the delineation of the water area. Among these two indices, MNDWI results are a more differentiated open water area that has greater positive values than NDWI, as it absorbs more shortwave-infrared (SWIR) wavelengths than near infrared (NIR) wavelengths. Built-up features have negative values and soil and vegetation also have negative values, as soil reflects more SWIR wavelengths than NIR wavelengths. Along the left bank, there is mainly deposition than on the right bank because of the elevation and geological structure. The derived results of channel pattern changes were validated by comparing them with the Sediment Transport Index (STI), and Stream Power Index (SPI). Integration of remote sensing data with GIS is an efficient and economical technique to assess land losses and channel changes in large rivers.