Evolution of Char lands in the Padma River in Bangladesh and its impacts on planform morphology of the river

Abstract

This paper examines the morphological evolution of the Char lands of the Padma River and its impact on planform morphology of the Padma. Drivers of the morphological evolution are also investigated. The study utilizes geospatial data derived from remotely sensed images taken between 1962 and 2022. Development through huge accretion and erosion in the Harirampur Char, repeated movement of Amirabad Char from the left bank to the right bank, and straight geomorphological connectivity between Paler Char and Chhitar Char were the main occurrences in the Char lands of the Padma. The morphological changes in Char lands are seen to enforce changes in the banklines around them and, in some cases, in the other co-existing Char lands. The expansion rate of Harirampur Char and the erosion rate in the banks around the Char were mutually related in a half-decadal delay mode. Due to this enforcement, the cyclic evolutions of Char lands contributed to the repeating channel pattern of the Padma. The dynamics of the Ganges-Jamuna confluence enhanced the morphological changes of the Padma, particularly in the upstream segment. High-magnitude floods contributed to making the morphological pattern of the Padma unstable.