Sediment cells and their dynamics along the coasts of India - A review

Coastal zone is dynamic in nature and is subjected to multiple interactions from marine, terrestrial, atmosphere, biosphere, fluvial systems and tectonic processes besides human interventions. Each coast is unique to its geographical location and set of physical interactions between land and oceanic parameters. Understanding these interactions are challenging and complicated in perception of its sustainability. A central concept in developing such a holistic approach is to view the coast as discrete functional units termed as 'Sediment Cells' rather than viewing it as a single continuous stretch of land surface. Sediment cell approach will provide a better understanding of the interrelation between the functions of the short term coastal processes and long term response and recovery of the coast. Based on sediment cell approach, a study was undertaken to delineate discrete functional units along the west and east coasts of varying spatial scales with confined sediment movement. Long term morphological changes, short term coastal processes and sediment dynamics were considered for the delineation. A total of 26 primary cells with 10 on the west and 16 on the east were identified from the study. These primary cells were further sub divided into 58 sub cells with 21 on the west and 37 on the east based on the sediment interruption factors either natural or manmade. The identified coastal sediment cells can be used in Integrated Coastal Zone Management (ICZM) especially to deal with shoreline changes and in the preparation of Shoreline Management Plans (SMP). To be specific, the delineated coastal sediment cells from the study are being used for the preparation of ICZM plans for Odisha and West Bengal.