Beach morphology, textural variation and erosion along the south-eastern coastal segment in Cox's Bazar-Teknaf, Bangladesh

Abstract

Coastal erosion is one of the key concerns on the longest beach on the earth along the southeastern Bengal coast in the Cox's Bazar-Teknaf area of Bangladesh. The objectives of the current attempt are to delineate the erosion-accretion scenario, cause, and consequence of erosion of the coast, textural variations of beach sediments and depositional conditions. These phenomena were illustrated through the interpretation of satellite imagery, characterizing beach morphology, sediment texture, tidal amplitudes, etc. The grain size of the sandy beach samples was explained through standard deviation, mean, kurtosis and skewness. Investigation implies that from 1989 to 2024, 1085 and 284 ha of land at a rate of 31 and 8 ha per year have degraded and accreted, respectively. Surge, cyclones, waves, current, human interference, sea level and climate fluctuations, beach morphology and high tidal amplitude are the prime influential factors for beach erosion at concern level. The matrices are mainly composed of well to moderately well sorted finer sand with silt. The result suggests that low energy tidal conditions prevailed along the coastline of the area. The findings would be advantageous for coastal scientists, researchers, academia, planners, policy makers, investors, other related stakeholders, etc. to understand the coastal procedure, beach morphology, sedimentation processes and cycles, and influence of southwest monsoon on the beach. It would also be useful for baseline information on granulometry, sedimentary environments of beach sediments, future beach nourishment scheme on the eroding shorelines, and for sustainable coastal zone management.