Abstract:
Sundarbans, the largest mangrove forest located over the GBM basin, has
impacted lives of millions over the years. Standing against various natural
disasters, rivers of Sundarbans have undergone major issues such as erosionaccretion of both the banks. The paper deals with a combination of remote
sensing and Digital Shoreline Analysis System (DSAS), studying temporal
behaviour of bank-lines along the main rivers of Sundarbans for the last three
decades. The course of main rivers spanning from southwest Baleswar to west
Bengal Bidyadhari within coverage of 10,000 sq. km. has been analyzed in this
study. DSAS, the extension tool of ArcGIS, was used for monitoring the rate-ofchange from multiple historic bank-line positions extracted from satellite
images. Comparison of historic bank-lines between different rivers of
Sundarbans was done based on Net Bank-line Movement (NBM) with an
interval of five years. Finally, the results were presented graphically to get a
better understanding of the bank-line behaviour. The study revealed that the
western region of mangrove prevails eroding behaviour than the eastern region.
Increased rates of riverward movement due to accretion was found from 2008-
2013. These results are important for future monitoring and proper
management within the coastal communities surrounding the mangrove forest.
