Simulation of channel dynamics of the Padma river considering seasonal variations: A GIS and statistical approach

Abstract

The Padma river, for being dynamic, is subjected to frequent and irregular shifting, which creates various socioeconomic, ecological, and environmental threats. Besides, due to having seasonal influences, these threats become more intense during the monsoon period than the dry season. Considering these issues, the present study aims to investigate the spatiotemporal changes of the Padma river during 1988–2019 with seasonal variations, also simulating the changes till 2035 using multi-temporal satellite imageries. GIS and ARIMA model is used to perform spatiotemporal analysis and simulation, respectively. This study focused on the lateral shifting of 21 cross-sections along the Padma river channel flowing through 19 upazilas of six (06) districts in the northwest side of Bangladesh. The study finds that the width of the channel changes so frequently to its right and left sides during the last 31 years. The width increases in the summer season, indicating destruction of the river vicinity over time. The highest lateral shifting of the channel has also occurred at the Bagha and Daulatpur upazilas. The river is likely to be shifted more than 11 km and 13 km (winter and summer, respectively) in the next 16 years, along with the cross-section X10 at Bagha and Daulatpur upazila. Besides, the river channel's sinuosity has decreased till 2011 while it has increased suddenly in 2019. On the other hand, the braided index of the river has increased till 2011 and fell in 2019.