Skip to main content

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

  • Review Article
  • Published:

Geomorphic change in the Ganges–Brahmaputra–Meghna delta

Abstract

More than 70% of large deltas are under threat from rising sea levels, subsidence and anthropogenic interferences, including the Ganges–Brahmaputra–Meghna (GBM) delta, the Earth’s largest and most populous delta system. The dynamic geomorphology of this delta is often overlooked in assessments of its vulnerability; consequently, development plans and previous management investments have been undermined by unanticipated geomorphic responses. In this Review, we describe GBM delta dynamics, examining these changes through the Drivers–Pressures–States–Impacts–Responses framework. Since the early Holocene, the GBM delta has evolved in response to a combination of tectonics, geology, changing river discharge and sea level rise, but the dynamics observed today are driven by a complex interplay of anthropogenic interferences and natural background processes. Contemporary geomorphic processes such as shoreline change, channel migration, sedimentation and subsidence can increase flooding and erosion, impacting biodiversity, ground and water contamination and local community livelihoods. Continued human disturbances to the GBM delta, such as curtailing sediment supplies, modifying channels and changing land use, could have a more direct influence on the future geomorphic balance of the delta than anthropogenic climate change and sea level rise. In order to contribute to long-term delta sustainability, adaptation responses must therefore be informed by an understanding of geomorphic processes, requiring increased transdisciplinary research on future delta dynamics at centennial timescales and collaboration across all governing bodies and stakeholders.

Key points

  • The interplay between long-term tectonic and eustatic sea level changes, sudden earthquake perturbances and large-scale man-made management schemes in the Ganges–Brahmaputra–Meghna (GBM) delta are the key drivers that shaped its evolution.

  • This review provides a spatial representation of the sediment budget, which is necessary for delta management decisions, including the potential for harnessing natural sedimentation processes to enhance land generation.

  • Mapping the spatio-temporal extent of documented geomorphic processes revealed gaps in understanding at the centennial scales and into the future, which are both critical to delta management decisions, as most infrastructures are expected to be effective for up to 100 years into the future.

  • Only 40% of the 427 reviewed publications assess geomorphic processes as interconnected, potentially resulting in a fragmented understanding of dynamics.

  • Geomorphic processes are mostly absent from models of flooding and water security in the GBM delta. These omissions undermine the validity of longer-term projections and call into question the appropriateness of management decisions that are based upon these models.

  • Anthropogenic disturbances could have a more direct influence on the future geomorphic balance of the GBM delta than climate change and sea level rise.

This is a preview of subscription content, access via your institution

Access options

Buy this article

Prices may be subject to local taxes which are calculated during checkout

Fig. 1: Location of the Ganges–Brahmaputra–Meghna delta.
Fig. 2: Distribution of geomorphic studies assessing different components of the DPSIR framework.
Fig. 3: Timeline of geomorphic evolution of the Ganges–Brahmaputra–Meghna delta.
Fig. 4: Sediment budget in the Ganges–Brahmaputra–Meghna delta system.
Fig. 5: Subsidence across the Ganges–Brahmaputra–Meghna delta.
Fig. 6: Predominant impacts of geomorphic change in the Ganges–Brahmaputra–Meghna delta.
Fig. 7: Key systemic gaps in scientific understanding of geomorphic change in the Ganges–Brahmaputra–Meghna delta.

Similar content being viewed by others

References

  1. Darby, S. E., Dunn, F. E., Nicholls, R. J., Rahman, M. & Riddy, L. A first look at the influence of anthropogenic climate change on the future delivery of fluvial sediment to the Ganges–Brahmaputra–Meghna delta. Environ. Sci. Process. Impacts 17, 1587–1600 (2015). This paper simulates future climate-driven sediment loads flowing to the GBM delta to the end of the twenty-first century, showing increases of up to 37% for the Ganges and 60% for the Brahmaputra.

    Article  Google Scholar 

  2. Nicholls, R. J. et al. Integrated assessment of social and environmental sustainability dynamics in the Ganges–Brahmaputra–Meghna delta, Bangladesh. Estuar. Coast. Shelf Sci. 183, 370–381 (2016). This paper demonstrates an integrated framework to assess the changing ecosystem services in the GBM delta and the implications for human well-being.

    Article  Google Scholar 

  3. Tessler, Z. D., Voeroesmarty, C. J., Overeem, I. & Syvitski, J. P. M. A model of water and sediment balance as determinants of relative sea level rise in contemporary and future deltas. Geomorphology 305, 209–220 (2018).

    Article  Google Scholar 

  4. Dunn, F. E. et al. Projections of declining fluvial sediment delivery to major deltas worldwide in response to climate change and anthropogenic stress. Environ. Res. Lett. 14, 084034 (2019).

    Article  Google Scholar 

  5. Rahman, M. et al. Recent sediment flux to the Ganges–Brahmaputra–Meghna delta system. Sci. Total. Environ. 643, 1054–1064 (2018). This paper presents a synthesis of sediment flux to the GBM delta system, illustrating reductions in current sediment delivery by up to 50% of previous estimates.

    Article  Google Scholar 

  6. Szabo, S. et al. Population dynamics, delta vulnerability and environmental change: comparison of the Mekong, Ganges–Brahmaputra and Amazon delta regions. Sustain. Sci. 11, 539–554 (2016).

    Article  Google Scholar 

  7. Goodbred, S. L. & Saito, Y. in Principles of Tidal Sedimentology (eds Davis Jr., R. A. & Dalrymple, R. W.) 129–149 (Springer, 2012).

  8. Hoitink, A. J. F., Wang, Z. B., Vermeulen, B., Huismans, Y. & Kaestner, K. Tidal controls on river delta morphology. Nat. Geosci. 10, 637–645 (2017).

    Article  Google Scholar 

  9. Woodroffe, C. D., Nicholls, R. J., Saito, Y., Chen, Z. & Goodbred, S. L. in Global Change and Integrated Coastal Management: The Asia-Pacific Region (ed. Harvey, N.) Vol. 10 277–314 (Springer, 2006).

  10. Edmonds, D. A., Caldwell, R. L., Brondizio, E. S. & Siani, S. M. O. Coastal flooding will disproportionately impact people on river deltas. Nat. Commun. 11, 4741 (2020).

    Article  Google Scholar 

  11. Auerbach, L. W. et al. Flood risk of natural and embanked landscapes on the Ganges–Brahmaputra tidal delta plain. Nat. Clim. Change 5, 153–157 (2015).

    Article  Google Scholar 

  12. Brown, S. & Nicholls, R. J. Subsidence and human influences in mega deltas: the case of the Ganges–Brahmaputra–Meghna. Sci. Total. Environ. 527, 362–374 (2015). This paper analyses rates of subsidence recorded across the literature and relates these findings to natural and human influences in the GBM delta.

    Article  Google Scholar 

  13. Tessler, Z. D. et al. Profiling risk and sustainability in coastal deltas of the world. Science 7, 638–643 (2015).

    Article  Google Scholar 

  14. Bangladesh Bureau of Statistics. Bangladesh Bureau of Statistics — Government of the People’s Republic of Bangladesh http://www.bbs.gov.bd/ (2019).

  15. Reitz, M. D. et al. Effects of tectonic deformation and sea level on river path selection: theory and application to the Ganges–Brahmaputra–Meghna river delta. J. Geophys. Res. Earth Surf. 120, 671–689 (2015).

    Article  Google Scholar 

  16. Allison, M. Historical changes in the Ganges–Brahmaputra delta front. J. Coast. Res. 14, 1269–1275 (1998).

    Google Scholar 

  17. Sarker, M. H., Akter, J., Ferdous, M. R. & Noor, F. Sediment dispersal processes and management in coping with climate change in the Meghna Estuary, Bangladesh. in Sediment Problems and Sediment Management in Asian River Basins (ed. Walling, D. E.), 349, 203–217 (IAHS, 2011). This text illustrates sediment dispersal processes in the estuary and their responses to different exogenic and anthropogenic forces to underpin adaptive sediment management in the face of climate change.

  18. Wilson, C. A. & Goodbred, S. L. Jr. Construction and maintenance of the Ganges–Brahmaputra–Meghna delta: linking process, morphology, and stratigraphy. Ann. Rev. Mar. Sci 7, 67–88 (2015). This paper reviews the evolving processes, morphology and stratigraphy of the GBM delta, defining the delta as a complex composite system of both fluvial and tidal dominance.

    Article  Google Scholar 

  19. Brammer, H. Bangladesh’s dynamic coastal regions and sea-level rise. Clim. Risk Manag. 1, 51–62 (2014).

    Article  Google Scholar 

  20. Giosan, L., Syvitski, J., Constantinescu, S. & Day, J. Protect the world’s deltas. Nature 516, 31–33 (2014).

    Article  Google Scholar 

  21. Syvitski, J. P. M. et al. Sinking deltas due to human activities. Nat. Geosci. 2, 681–686 (2009).

    Article  Google Scholar 

  22. Hall, J. W. et al. Coping with the curse of freshwater variability. Science 346, 429–430 (2014).

    Article  Google Scholar 

  23. Lázár, A. N., Nicholls, R. J., Hall, J. W., Barbour, E. J. & Haque, A. Contrasting development trajectories for coastal Bangladesh to the end of century. Reg. Env. Change 20, 93 (2020).

    Article  Google Scholar 

  24. Nicholls, R., Adger, W. N., Hutton, C. & Hanson, S. Deltas in the Anthropocene (Palgrave MacMillan, 2019).

  25. Angamuthu, B., Darby, S. E. & Nicholls, R. J. Impacts of natural and human drivers on the multi-decadal morphological evolution of tidally-influenced deltas. Proc. Math. Phys. Eng. Sci. 474, 20180396 (2018).

    Google Scholar 

  26. Nicholls, R. J. & Goodbred, S. Towards the integrated assessment of the Ganges-Brahmaputra Delta. in Mega-Deltas of Asia: Geological Evolution and Human Impact 168–181 (eds Chen, Z., Saito, Y., Goodbred Jr., S.L.) (China Ocean Press, 2004).

  27. European Environment Agency (EEA) Europe’s Environment: The Dobris Assessment (EEA, 1995).

  28. Organisation for economic co-operation and development (OECD) Core Set of Indicators for Environmental Performance Reviews (OECD, 1993).

  29. General Economics Division (GED) Bangladesh Delta Plan 2100 (Bangladesh Planning Commission, 2018).

  30. Alam, M., Alam, M. M., Curray, J. R., Chowdhury, M. L. R. & Gani, M. R. An overview of the sedimentary geology of the Bengal Basin in relation to the regional tectonic framework and basin-fill history. Sediment. Geol. 155, 179–208 (2003).

    Article  Google Scholar 

  31. Goodbred, S., Kuehl, S., Steckler, M. & Sarker, M. Controls on facies distribution and stratigraphic preservation in the Ganges–Brahmaputra delta sequence. Sediment. Geol. 155, 301–316 (2003).

    Article  Google Scholar 

  32. Morgan, J. P. & McIntire, W. G. Quaternary geology of the Bengal Basin, East Pakistan and India. Bull. Geol. Soc. Am. 70, 319–342 (1959).

    Article  Google Scholar 

  33. Steckler, M. S. et al. Locked and loading megathrust linked to active subduction beneath the Indo-Burman ranges. Nat. Geosci. 9, 615–618 (2016).

    Article  Google Scholar 

  34. Allison, M., Khan, S., Goodbred, S. & Kuehl, S. Stratigraphic evolution of the late Holocene Ganges–Brahmaputra lower delta plain. Sediment. Geol. 155, 317–342 (2003).

    Article  Google Scholar 

  35. Sarkar, A. et al. Evolution of Ganges–Brahmaputra western delta plain: clues from sedimentology and carbon isotopes. Quat. Sci. Rev. 28, 2564–2581 (2009).

    Article  Google Scholar 

  36. Sarker, M. H. Morphological response of the Brahmaputra–Padma–Lower Meghna river system to the Assam earthquake of 1950. Thesis. Univ. Nottingham (2009).

  37. Goodbred, S. & Kuehl, S. Enormous Ganges–Brahmaputra sediment discharge during strengthened early Holocene monsoon. Geology 28, 1083–1086 (2000).

    Article  Google Scholar 

  38. Goodbred, S. L. Jr. et al. Piecing together the Ganges–Brahmaputra–Meghna River delta: Use of sediment provenance to reconstruct the history and interaction of multiple fluvial systems during Holocene delta evolution. Geol. Soc. Am. Bull. 126, 1495–1510 (2014). This paper uses sediment provenance to detail the evolution of the GBM delta during the Holocene period.

    Article  Google Scholar 

  39. Grall, C. et al. A base-level stratigraphic approach to determining Holocene subsidence of the Ganges–Meghna–Brahmaputra delta plain. Earth Planet. Sci. Lett. 499, 23–36 (2018).

    Article  Google Scholar 

  40. Goodbred, S. & Kuehl, S. The significance of large sediment supply, active tectonism, and eustasy on margin sequence development: Late Quaternary stratigraphy and evolution of the Ganges–Brahmaputra delta. Sediment. Geol. 133, 227–248 (2000).

    Article  Google Scholar 

  41. Akter, J., Sarker, M. H., Popescu, I. & Roelvink, D. Evolution of the Bengal delta and its prevailing processes. J. Coast. Res. 32, 1212–1226 (2016).

    Article  Google Scholar 

  42. Coleman, J. M. Brahmaputra river: channel processes and sedimentation. Sediment. Geol. 3, 129–239 (1969).

    Article  Google Scholar 

  43. Fergusson, J. On recent changes in the delta of the ganges. Proc. Geol. Soc. 19, 321–354 (1863).

    Google Scholar 

  44. Bristow, C. S. Gradual avulsion, river metamorphosis and reworking by underfit streams: a modern example of the Brahmaputra River in Bangladesh and a possible ancient example in the Spanish Pyrenees. Spec. Publs int. Ass. Sediment. 28, 221-230 (1999).

    Google Scholar 

  45. Pickering, J. L. et al. Late Quaternary sedimentary record and Holocene channel avulsions of the Jamuna and Old Brahmaputra River valleys in the upper Bengal delta plain. Geomorphology 227, 123–136 (2014).

    Article  Google Scholar 

  46. Khan, S. R. & Islam, B. Holocene stratigraphy of the lower Ganges–Brahmaputra river delta in Bangladesh. Front. Earth Sci. China 2, 393–399 (2008).

    Article  Google Scholar 

  47. Sincavage, R., Goodbred, S. & Pickering, J. Holocene Brahmaputra river path selection and variable sediment bypass as indicators of fluctuating hydrologic and climate conditions in Sylhet Basin, Bangladesh. Basin Res. 30, 302–320 (2018).

    Article  Google Scholar 

  48. Krien, Y. et al. Present-day subsidence in the Ganges–Brahmaputra–Meghna delta: eastern amplification of the holocene sediment loading contribution. Geophys. Res. Lett. 46, 10764–10772 (2019).

    Article  Google Scholar 

  49. Bomer, E. J., Wilson, C. A. & Datta, D. K. An integrated approach for constraining depositional zones in a tide-influenced river: insights from the Gorai River, southwest Bangladesh. Water, 11, 2047 (2019).

    Article  Google Scholar 

  50. Bomer, E. J., Wilson, C. A., Hale, R. P., Hossain, A. N. M. & Rahman, F. M. A. Surface elevation and sedimentation dynamics in the Ganges–Brahmaputra tidal delta plain, Bangladesh: evidence for mangrove adaptation to human-induced tidal amplification. Catena 187, 104312 (2020).

    Article  Google Scholar 

  51. Hale, R., Bain, R., Goodbred, S. Jr. & Best, J. Observations and scaling of tidal mass transport across the lower Ganges–Brahmaputra delta plain: implications for delta management and sustainability. Earth Surf. Dyn. 7, 231–245 (2019).

    Article  Google Scholar 

  52. Rogers, K. G., Goodbred, S. L. Jr. & Mondal, D. R. Monsoon sedimentation on the ‘abandoned’ tide-influenced Ganges–Brahmaputra delta plain. Estuar. Coast. And. Shelf Sci. 131, 297–309 (2013).

    Article  Google Scholar 

  53. Haque, A. & Nicholls, R. J. Floods and the Ganges-Brahmaputra-Meghna Delta, in Ecosystem Services for Well-Being in Deltas: Integrated Assessment for Policy Analysis(eds Nicholls, R. J., Hutton, C.W., Adger, W.N., Hanson, S.E., Rahman, M.M., Salehin, M.) (Palgrave Macmillan, London, 2017)

  54. Hossain, M. A., Gan, T. Y. & Baki, A. B. M. Assessing morphological changes of the Ganges river using satellite images. Quat. Int. 304, 142–155 (2013).

    Article  Google Scholar 

  55. Mirza, M. M. Q. Hydrological changes in the Ganges system in Bangladesh in the post-Farakka period. Hydrol. Sci. J. 42, 613–631 (1997).

    Article  Google Scholar 

  56. Murshed, S. B., Rahman, R. & Kaluarachchi, J. J. Changes in hydrology of the Ganges delta of Bangladesh and corresponding impacts on water resources. J. Am. Water Resour. Assoc. 55, 800–823 (2019).

    Article  Google Scholar 

  57. Rahman, Md. M. & Rahaman, M. M. Impacts of Farakka Barrage on hydrological flow of Ganges river and environment in Bangladesh. Sustain. Water Resour. Manag. 4, 767–780 (2018).

    Article  Google Scholar 

  58. Islam, A. & Guchhait, S. K. Characterizing cross-sectional morphology and channel inefficiency of lower Bhagirathi River, India, in post-Farakka Barrage condition. Nat. Hazards 103, 3803–3836 (2020).

    Article  Google Scholar 

  59. Islam, A. & Guchhait, S. K. Analysing the influence of Farakka Barrage Project on channel dynamics and meander geometry of Bhagirathi river of West Bengal, India. Arab. J. Geosci. 10, 245 (2017).

    Article  Google Scholar 

  60. Khatun, S., Das, S. & Pal, S. Exploring the ambient environment for charland formation in Rajmahal downstream Ganga river of eastern India in post Farakka Barrage period. Spat. Inf. Res. 26, 337–346 (2018).

    Article  Google Scholar 

  61. Anwar, M. S. & Takewaka, S. Analyses on phenological and morphological variations of mangrove forests along the southwest coast of Bangladesh. J. Coast. Conserv. 18, 339–357 (2014).

    Article  Google Scholar 

  62. Mirza, M. M. Q. Diversion of the Ganges water at Farakka and its effects on salinity in Bangladesh. Environ. Manag. 22, 711–722 (1998).

    Article  Google Scholar 

  63. Aziz, A. & Paul, A. R. Bangladesh Sundarbans: present status of the environment and biota. Diversity 7, 242–269 (2015).

    Article  Google Scholar 

  64. Adel, M. M. The background state leading to arsenic contamination of Bengal Basin groundwater. J. Water Health 3, 435–452 (2005).

    Article  Google Scholar 

  65. Borgomeo, E., Hall, J. W. & Salehin, M. Avoiding the water-poverty trap: insights from a conceptual human–water dynamical model for coastal Bangladesh. Int. J. Water Resour. Dev. 34, 900–922 (2018).

    Article  Google Scholar 

  66. Gain, A. K., Benson, D., Rahman, R., Datta, D. K. & Rouillard, J. J. Tidal river management in the south west Ganges–Brahmaputra delta in Bangladesh: moving towards a transdisciplinary approach? Environ. Sci. Policy 75, 111–120 (2017).

    Article  Google Scholar 

  67. Nowreen, S., Jalal, M. R. & Khan, M. S. A. Historical analysis of rationalizing south west coastal polders of Bangladesh. Water Policy 16, 264–279 (2014).

    Article  Google Scholar 

  68. Wilson, C. et al. Widespread infilling of tidal channels and navigable waterways in the human-modified tidal deltaplain of southwest Bangladesh. Elementa Sci. Anthrop. 5, 74 (2017).

    Article  Google Scholar 

  69. Dewan, A. et al. Assessing channel changes of the Ganges–Padma river system in Bangladesh using Landsat and hydrological data. Geomorphology 276, 257–279 (2017).

    Article  Google Scholar 

  70. Hinderer, M. From gullies to mountain belts: a review of sediment budgets at various scales. Sediment. Geol. 280, 21–59 (2012).

    Article  Google Scholar 

  71. Allison, M. A., Kuehl, S. A., Martin, T. C. & Hassan, A. Importance of flood-plain sedimentation for river sediment budgets and terrigenous input to the oceans: insights from the Brahmaputra–Jamuna River. Geology 26, 175–178 (1998).

    Article  Google Scholar 

  72. Islam, M., Begum, S., Yamaguchi, Y. & Ogawa, K. The Ganges and Brahmaputra rivers in Bangladesh: basin denudation and sedimentation. Hydrol. Process. 13, 2907–2923 (1999).

    Article  Google Scholar 

  73. Goodbred, S. & Kuehl, S. Holocene and modern sediment budgets for the Ganges–Brahmaputra river system: evidence for highstand dispersal to flood-plain, shelf, and deep-sea depocenters. Geology 27, 559–562 (1999).

    Article  Google Scholar 

  74. Dunn, F. E. et al. Projections of historical and 21st century fluvial sediment delivery to the Ganges–Brahmaputra–Meghna, Mahanadi, and Volta deltas. Sci. Total. Environ. 642, 105–116 (2018). This paper uses the WBMsed model to project sediment delivery to the GBM, Mahanadi and Volta deltas, showing that socio-economic impacts can have stronger effects than climate change on sediment delivery.

    Article  Google Scholar 

  75. Adnan, M. S. G., Haque, A. & Hall, J. W. Have coastal embankments reduced flooding in Bangladesh? Sci. Total. Environ. 682, 405–416 (2019).

    Article  Google Scholar 

  76. Slater, L. J., Singer, M. B. & Kirchner, J. W. Hydrologic versus geomorphic drivers of trends in flood hazard. Geophys. Res. Lett. 42, 370–376 (2015).

    Article  Google Scholar 

  77. Wasson, R. J. A sediment budget for the Ganga–Brahmaputra catchment. Curr. Sci. 84, 1041–1047 (2003).

    Google Scholar 

  78. Sarker, M. H., Thorne, C. R., Aktar, M. N. & Ferdous, M. R. Morpho-dynamics of the Brahmaputra–Jamuna River, Bangladesh. Geomorphology 215, 45–59 (2014).

    Article  Google Scholar 

  79. Thorne, C. R., Russell, A. P. G. & Alam, M. K. Planform pattern and channel evolution of the Brahmaputra river, Bangladesh. Geophys. Soc. Lond. 75, 257–256 (1993).

    Google Scholar 

  80. Takagi, T. et al. Channel braiding and stability of the Brahmaputra river, Bangladesh, since 1967: GIS and remote sensing analyses. Geomorphology 85, 294–305 (2007).

    Article  Google Scholar 

  81. Ophra, S. J., Begum, S., Islam, R. & Islam, Md. N. Assessment of bank erosion and channel shifting of Padma River in Bangladesh using RS and GIS techniques. Spat. Inf. Res. 26, 599–605 (2018).

    Article  Google Scholar 

  82. Mahmud, M. I. et al. Assessing bank dynamics of the Lower Meghna River in Bangladesh: an integrated GIS–DSAS approach. Arab. J. Geosci. 13, 602 (2020).

    Article  Google Scholar 

  83. Hanebuth, T. J. J., Kudrass, H. R., Linstaedter, J., Islam, B. & Zander, A. M. Rapid coastal subsidence in the central Ganges–Brahmaputra delta (Bangladesh) since the 17th century deduced from submerged salt-producing kilns. Geology 41, 987–990 (2013).

    Article  Google Scholar 

  84. Steckler, M. S. et al. Modeling Earth deformation from monsoonal flooding in Bangladesh using hydrographic, GPS, and Gravity Recovery and Climate Experiment (GRACE) data. J. Geophys. Res. Solid Earth 115, B8407 (2010).

    Article  Google Scholar 

  85. Pethick, J. & Orford, J. D. Rapid rise in effective sea-level in southwest Bangladesh: its causes and contemporary rates. Glob. Planet. Change 111, 237–245 (2013).

    Article  Google Scholar 

  86. Hoque, M. & Alam, M. Subsidence in the lower deltaic areas of Bangladesh. Mar. Geodesy 20, 105–120 (1997).

    Article  Google Scholar 

  87. Ahmed, A., Drake, F., Nawaz, R. & Woulds, C. Where is the coast? Monitoring coastal land dynamics in Bangladesh: an integrated management approach using GIS and remote sensing techniques. Ocean Coast. Manag. 151, 10–24 (2018).

    Article  Google Scholar 

  88. Hussain, M. A., Tajima, Y., Gunasekara, K., Rana, S. & Hasan, R. Recent coastline changes at the eastern part of the Meghna Estuary using PALSAR and Landsat images. IOP Conference Series: Earth and Environmental Science 20 (2014).

  89. Khan, E. & Hussain, N. Coastline dynamics and raising landform: a geo-informatics based study on the Bay of Bengal, Bangladesh. Indonesian J. Geogr. 50, 41–48 (2018).

    Article  Google Scholar 

  90. Shearman, P., Bryan, J. & Walsh, J. P. Trends in deltaic change over three decades in the Asia-Pacific region. J. Coast. Res. 29, 1169–1183 (2013).

    Article  Google Scholar 

  91. Umitsu, M. Landforms and floods in the ganges delta and coastal lowland of Bangladesh. Mar. Geodesy 20, 77–87 (1997).

    Article  Google Scholar 

  92. Sarwar, M. G. M. & Woodroffe, C. D. Rates of shoreline change along the coast of Bangladesh. J. Coast. Conserv. 17, 515–526 (2013).

    Article  Google Scholar 

  93. Rahman, A. F., Dragoni, D. & El-Masri, B. Response of the Sundarbans coastline to sea level rise and decreased sediment flow: a remote sensing assessment. Remote. Sens. Environ. 115, 3121–3128 (2011).

    Article  Google Scholar 

  94. Raha, A., Das, S., Banerjee, K. & Mitra, A. Climate change impacts on Indian Sunderbans: a time series analysis (1924–2008). Biodivers. Conserv. 21, 1289–1307 (2012).

    Article  Google Scholar 

  95. Bera, R. & Maiti, R. Quantitative analysis of erosion and accretion (1975–2017) using DSAS — a study on Indian Sundarbans. Regional Stud. Mar. Sci. 28, 100583 (2019).

    Article  Google Scholar 

  96. Bain, R. L., Hale, R. P. & Goodbred, S. L. Flow reorganization in an anthropogenically modified tidal channel network: an example from the southwestern Ganges–Brahmaputra–Meghna delta. J. Geophys. Res. Earth Surf. 124, 2141–2159 (2019).

    Article  Google Scholar 

  97. Adel, M. M. Downstream ecocide from upstream water piracy. Am. J. Environ. Sci. 8, 528–548 (2012).

    Article  Google Scholar 

  98. Ahmed, A. U. Living in the downstream: Development in peril. in Interlinking of Rivers in India: Issues and Concerns 153–168 (eds Mirza, M.M.Q., Ahmed, A.U., Ahmad, Q.K.) (2008).

  99. Khan, N. I. & Islam, A. Quantification of erosion patterns in the Brahmaputra–Jamuna River using geographical information system and remote sensing techniques. Hydrol. Process. 17, 959–966 (2003).

    Article  Google Scholar 

  100. Rahman, M. A. T. M. T., Islam, S. & Rahman, S. H. Coping with flood and riverbank erosion caused by climate change using livelihood resources: a case study of Bangladesh. Clim. Dev. 7, 185–191 (2015).

    Article  Google Scholar 

  101. Bangladesh’s disappearing river lands. The New Humanitarian https://www.thenewhumanitarian.org/Bangladesh-river-erosion-engulfs-homes-climate-change-migration (2019).

  102. Best, J. L., Ashworth, P. J., Sarker, M. H. & Roden, J. E. The Brahmaputra-Jamuna River, Bangladesh. Large Rivers: Geomorphology and Management, 395–433 (eds Gupta, A.) (Wiley, 2008).

  103. Billah, M. M. Mapping and monitoring erosion–accretion in an alluvial river using satellite imagery — the river bank changes of the Padma river in Bangladesh. Quaest. Geograph. 37, 87–95 (2018).

    Article  Google Scholar 

  104. Saleem, A. et al. Spatial and temporal variations of erosion and accretion: a case of a large tropical river. Earth Syst. Environ. 4, 167–181 (2020).

    Article  Google Scholar 

  105. Ayeb-Karlsson, S., van der Geest, K., Ahmed, I., Huq, S. & Warner, K. A people-centred perspective on climate change, environmental stress, and livelihood resilience in Bangladesh. Sustain. Sci. 11, 679–694 (2016).

    Article  Google Scholar 

  106. Sultana, R., Alam, M. S. & Selim, S. A. Household level coping strategies for flood disaster. The Environmental Sustainable Development Goals in Bangladesh. 96–112 (eds Selim, S.A., Saha, S.K., Sultana, R., Roberts, C.) (Taylor & Francis Group, 2018).

  107. Sarker, M. H., Huque, I. & Alam, M. Rivers, chars and char dwellers of Bangladesh. Int. J. River Basin Manag. 1, 61–80 (2003).

    Article  Google Scholar 

  108. Dewan, C., Mukherji, A. & Buisson, M.-C. Evolution of water management in coastal Bangladesh: from temporary earthen embankments to depoliticized community-managed polders. Water Int. 40, 401–416 (2015).

    Article  Google Scholar 

  109. Benner, S. G. & Fendorf, S. Arsenic in South Asia groundwater. Geogr. Compass 4, 1532–1552 (2010).

    Article  Google Scholar 

  110. Huq, M. E. et al. Arsenic in a groundwater environment in Bangladesh: occurrence and mobilization. J. Environ. Manag. 262, 110318 (2020).

    Article  Google Scholar 

  111. Mahmud, M. I., Sultana, S., Hasan, M. A. & Ahmed, K. M. Variations in hydrostratigraphy and groundwater quality between major geomorphic units of the western Ganges delta plain, SW Bangladesh. Appl. Water Sci. 7, 2919–2932 (2017).

    Article  Google Scholar 

  112. Ravenscroft, P., Burgess, W. G., Ahmed, K. M., Burren, M. & Perrin, J. Arsenic in groundwater of the Bengal Basin, Bangladesh: distribution, field relations, and hydrogeological setting. Hydrogeol. J. 13, 727–751 (2005).

    Article  Google Scholar 

  113. van Geen, A. et al. Flushing history as a hydrogeological control on the regional distribution of arsenic in shallow groundwater of the Bengal Basin. Environ. Sci. Technol. 42, 2283–2288 (2008).

    Article  Google Scholar 

  114. Acharyya, S. K., Lahiri, S., Raymahashay, B. C. & Bhowmik, A. Arsenic toxicity of groundwater in parts of the Bengal Basin in India and Bangladesh: the role of Quaternary stratigraphy and Holocene sea-level fluctuation. Environ. Geol. 39, 1127–1137 (2000).

    Article  Google Scholar 

  115. Yu, W. H., Harvey, C. M. & Harvey, C. F. Arsenic in groundwater in Bangladesh: a geostatistical and epidemiological framework for evaluating health effects and potential remedies. Water Resour. Res. 39, 1146–1163 https://doi.org/10.1029/2002WR001327 (2003).

  116. Department of Public Health Engineering (DPHE), Government of Bangladesh, British Geologic Survey & Mott MacDonald Ltd. Groundwater Studies for Arsenic Contamination in Bangladesh, Phase I: Rapid Investigation Phase (British Geological Survey and Mott MacDonald Ltd, 1999).

  117. Bhowmick, S. et al. Arsenic mobilization in the aquifers of three physiographic settings of West Bengal, India: understanding geogenic and anthropogenic influences. J. Hazard. Mater. 262, 915–923 (2013).

    Article  Google Scholar 

  118. Weinman, B. et al. Contributions of floodplain stratigraphy and evolution to the spatial patterns of groundwater arsenic in Araihazar, Bangladesh. GSA Bull. 120, 1567–1580 (2008).

    Article  Google Scholar 

  119. Tareq, S. M., Safiullah, S., Anawar, H. M., Rahman, M. M. & Ishizuka, T. Arsenic pollution in groundwater: a self-organizing complex geochemical process in the deltaic sedimentary environment, Bangladesh. Sci. Total. Environ. 313, 213–226 (2003).

    Article  Google Scholar 

  120. Ali, M. M., Ishiga, H. & Wakatsuki, T. Influence of soil type and properties on distribution and changes in arsenic contents of different paddy soils in Bangladesh. Soil. Sci. Plant. Nutr. 49, 111–123 (2003).

    Article  Google Scholar 

  121. Mihajlov, I. et al. Arsenic contamination of Bangladesh aquifers exacerbated by clay layers. Nat. Commun. 11, 2244 (2020).

    Article  Google Scholar 

  122. Berube, M. et al. The fate of arsenic in groundwater discharged to the Meghna River, Bangladesh. Environ. Chem. 15, 29–45 (2018).

    Article  Google Scholar 

  123. Jung, H. B., Zheng, Y., Rahman, M. W., Rahman, M. M. & Ahmed, K. M. Redox zonation and oscillation in the hyporheic zone of the Ganges–Brahmaputra–Meghna delta: implications for the fate of groundwater arsenic during discharge. Appl. Geochem. 63, 647–660 (2015).

    Article  Google Scholar 

  124. Datta, S. et al. Redox trapping of arsenic during groundwater discharge in sediments from the Meghna riverbank in Bangladesh. PNAS 106, 16930–16935 (2009).

    Article  Google Scholar 

  125. McArthur, J. M. et al. Natural organic matter in sedimentary basins and its relation to arsenic in anoxic ground water: the example of West Bengal and its worldwide implications. Appl. Geochem. 19, 1255–1293 (2004).

    Article  Google Scholar 

  126. McArthur, J. M. et al. How paleosols influence groundwater flow and arsenic pollution: a model from the Bengal Basin and its worldwide implication. Water Resour. Res. 44, 11 https://doi.org/10.1029/2007WR006552 (2008).

  127. Hoque, M. A., Burgess, W. G., Shamsudduha, M. & Ahmed, K. M. Delineating low-arsenic groundwater environments in the Bengal Aquifer System, Bangladesh. Appl. Geochem. 26, 614–623 (2011).

    Article  Google Scholar 

  128. Acharyya, S. K. Arsenic levels in groundwater from quaternary alluvium in the ganga plain and the Bengal Basin, Indian subcontinent: insights into influence of stratigraphy. Gondwana Res. 8, 55–66 (2005).

    Article  Google Scholar 

  129. Edmunds, M. W., Ahmed, K. M. & Whitehead, P. G. A review of arsenic and its impacts in groundwater of the Ganges–Brahmaputra–Meghna delta, Bangladesh. Environ. Sci. Process. Impacts 17, 1032–1046 (2015).

    Article  Google Scholar 

  130. Chakraborty, M. et al. Modeling regional-scale groundwater arsenic hazard in the transboundary Ganges River Delta, India and Bangladesh: infusing physically-based model with machine learning. Sci. Total. Environ. 748, 141107 (2020).

    Article  Google Scholar 

  131. Ahmed, K. M. et al. Arsenic enrichment in groundwater of the alluvial aquifers in Bangladesh: an overview. Appl. Geochem. 19, 181–200 (2004).

    Article  Google Scholar 

  132. Acharyya, S. & Shah, B. Groundwater arsenic pollution affecting deltaic West Bengal, India. Curr. Sci. 99, 1787–1794 (2010).

    Google Scholar 

  133. Benneyworth, L. et al. Drinking water insecurity: water quality and access in coastal south-western Bangladesh. Int. J. Environ. Health Res. 26, 508–524 (2016).

    Article  Google Scholar 

  134. Rahman, M. M. et al. Salinization in large river deltas: drivers, impacts and socio-hydrological feedbacks. Water Security 6, 100024 (2019).

    Article  Google Scholar 

  135. Ayers, J. C. et al. Sources of salinity and arsenic in groundwater in southwest Bangladesh. Geochem.Trans. 17, 4 (2016).

    Article  Google Scholar 

  136. Worland, S. C., Hornberger, G. M. & Goodbred, S. L. Source, transport, and evolution of saline groundwater in a shallow Holocene aquifer on the tidal deltaplain of southwest Bangladesh. Water Resour. Res. 51, 5791–5805 (2015).

    Article  Google Scholar 

  137. Mirza, M. & Hossain, M. A. Adverse effects on agriculture in the Ganges basin in Bangladesh. in The Ganges Water Diversion: Environmental Effects and Implications. Water Sci. Technol. 177–196 https://doi.org/10.1007/978-1-4020-2792-5_9 (2004).

  138. Roy, K., Gain, A. K., Mallick, B. & Vogt, J. Social, hydro-ecological and climatic change in the southwest coastal region of Bangladesh. Reg. Environ. Change 17, 1895–1906 (2017).

    Article  Google Scholar 

  139. Paprocki, K. Threatening dystopias: development and adaptation regimes in Bangladesh. Ann. Am. Assoc. Geogr. 108, 955–973 (2018).

    Google Scholar 

  140. Islam, S. & Gnauck, A. Water salinity investigation in the Sundarbans rivers in Bangladesh. Int. J. Water 6, 74–91 (2011).

    Article  Google Scholar 

  141. Islam, S. N. Sundarbans a dynamic ecosystem: an overview of opportunities, threats and tasks. Coast. Res. 30, 29–58 (2019).

    Article  Google Scholar 

  142. Awty-Carroll, K., Bunting, P., Hardy, A. & Bell, G. Using continuous change detection and classification of landsat data to investigate long-term mangrove dynamics in the sundarbans region. Remote. Sens. 11, 2833 (2019).

    Article  Google Scholar 

  143. Ghosh, M. K., Kumar, L. & Roy, C. Mapping long-term changes in mangrove species composition and distribution in the sundarbans. Forests 7, 305 (2016).

    Article  Google Scholar 

  144. Sievers, M. et al. Indian Sundarbans mangrove forest considered endangered under Red List of Ecosystems, but there is cause for optimism. Biol. Conserv. 251, 108751 (2020).

    Article  Google Scholar 

  145. Miah, M. S. Climatic and anthropogenic factors changing spawning pattern and production zone of Hilsa fishery in the Bay of Bengal. Weather. Clim. Extremes 7, 109–115 (2015).

    Article  Google Scholar 

  146. Ahmed, N., Rahman, S., Bunting, S. & Brugere, C. Socio-economic and ecological challenges of small-scale fishing and strategies for its sustainable management: a case study of the Old Brahmaputra River, Bangladesh. Singap. J. Trop.Geogr. 34, 86–102 (2013).

    Article  Google Scholar 

  147. Chowdhooree, I. Indigenous knowledge for enhancing community resilience: an experience from the south-western coastal region of Bangladesh. Int. J. Disaster Risk Reduct. 40, 101259 (2019).

    Article  Google Scholar 

  148. Talchabhadel, R., Nakagawa, H. & Kawaike, K. Tidal River Management (TRM) and Tidal Basin Management (TBM): A case study on Bangladesh 3rd Eur. Conf. Flood Risk Management (Floodrisk 2016) (ed. Lang, M., Klijn, F. and Samuels, P.) Vol. 7 (2016).

  149. van Staveren, M. F., Warner, J. F. & Khan, M. S. A. Bringing in the tides. From closing down to opening up delta polders via Tidal River Management in the southwest delta of Bangladesh. Water Policy 19, 147–164 (2017).

    Article  Google Scholar 

  150. Al Masud, M. M., Gain, A. K. & Azad, A. K. Tidal river management for sustainable agriculture in the Ganges–Brahmaputra delta: Implication for land use policy. Land. Use Policy 92, 104443 (2020).

    Article  Google Scholar 

  151. Penning-Rowsell, E. C., Sultana, P. & Thompson, P. M. The ‘last resort’? Population movement in response to climate-related hazards in Bangladesh. Environ. Sci. Policy 27, S44–S59 (2013).

    Article  Google Scholar 

  152. Uddin, J., Masum Jujuly, M., Hossain, M. & Rahman, A. Applicability of reinforced concrete spurs in river bank protection: A case study in Bangladesh. 11th Int. Multidisciplinary Scientific Geoconf. and EXPO — Modern Management of Mine Producing, Geology and Environmental Protection, SGEM 2, 777–784 (2011).

    Google Scholar 

  153. Dasgupta, S. et al. Climate proofing infrastructure in Bangladesh: the incremental cost of limiting future flood damage. J. Environ. Dev. 20, 167–190 (2011).

    Article  Google Scholar 

  154. Darby, S. E., Nicholls, R. J., Rahman, M. M., Brown, S. & Karim, M. R. A Sustainable Future Supply of Fluvial Sediment for the Ganges-Brahmaputra Delta, in Ecosystem Services for Well-Being in Deltas: Integrated Assessment for Policy Analysis (eds Nicholls, R. J., Hutton, C. W., Adger, W. N., Hanson, S. E., Rahman, M. M., Salehin, M.) (Palgrave Macmillan, London, 2017).

  155. Khalequzzaman, M. Recent Floods in Bangladesh — possible causes and solutions. Nat. Hazards 9, 65–80 (1994).

    Article  Google Scholar 

  156. Sinha, R. & Ghosh, S. Understanding dynamics of large rivers aided by satellite remote sensing: a case study from Lower Ganga plains, India. Geocarto Int. 27, 207–219 (2012).

    Article  Google Scholar 

  157. Nakagawa, H., Zhang, H., Baba, Y., Kawaike, K. & Teraguchi, H. Hydraulic characteristics of typical bank-protection works along the Brahmaputra/Jamuna River, Bangladesh. J. Flood Risk Manag. 6, 345–359 (2013).

    Article  Google Scholar 

  158. Mutahara, M., Warner, J. F. & Khan, M. S. A. Multi-stakeholder participation for sustainable delta management: a challenge of the socio-technical transformation in the management practices in Bangladesh. Int. J. Sustain. Dev. World Ecol. 27, 611–624 (2020).

    Article  Google Scholar 

  159. Chamberlain, E. L. et al. Integrating geochronologic and instrumental approaches across the Bengal Basin. Earth Surf. Process. Landf. 45, 56–74 (2020).

    Article  Google Scholar 

  160. Kopp, J. & Kim, W. The effect of lateral tectonic tilting on fluviodeltaic surficial and stratal asymmetries: experiment and theory. Basin Res. 27, 517–530 (2015).

    Article  Google Scholar 

  161. Di Baldassarre, G. et al. Socio-hydrology: conceptualising human–flood interactions. Hydrol. Earth Syst. Sci. 17, 3295–3303 (2013).

    Article  Google Scholar 

  162. Di Baldassarre, G., Yan, K., Ferdous, Md. R. & Brandimarte, L. The interplay between human population dynamics and flooding in Bangladesh: a spatial analysis. Evolving Water Resources Systems: Understanding, Predicting And Managing Water–Society Interactions (ed. Castellarin, A., Ceola, S., Toth, E. and Montanari, A.), 364, 188–191 (IAHS Press, 2014).

  163. Di Baldassarre, G. D. et al. Debates — Perspectives on socio-hydrology: capturing feedbacks between physical and social processes. Water Resour. Res. 51, 4770–4781 (2015).

    Article  Google Scholar 

  164. Liu, J. et al. Complexity of coupled human and natural systems. Science 317, 1513–1516 (2007).

    Article  Google Scholar 

  165. Sivapalan, M., Savenije, H. H. G. & Blöschl, G. Socio-hydrology: a new science of people and water: Invited Commentary. Hydrol. Process. 26, 1270–1276 (2012).

    Article  Google Scholar 

  166. Van Deursen, W. DSD-INT 2017 Meta-modelling for decision support (Deltares, 2017).

  167. Akhter, S. et al. Predicting spatiotemporal changes of channel morphology in the reach of Teesta River, Bangladesh using GIS and ARIMA modeling. Quat. Int. 513, 80–94 (2019).

    Article  Google Scholar 

  168. Baiyu, G. New concerns for transboundary rivers as China discusses diversion. The Third Pole https://www.thethirdpole.net/2020/01/14/new-concerns-for-transboundary-rivers-as-china-discusses-diversion/ (2020).

  169. Higgins, S. A., Overeem, I., Rogers, K. G. & Kalina, E. A. River linking in India: downstream impacts on water discharge and suspended sediment transport to deltas. Elementa Sci. Anthrop. 6, 20 (2018).

    Article  Google Scholar 

  170. European Commission. Global surface water explorer. European Commission https://global-surface-water.appspot.com/ (2019).

  171. Ceola, S., Laio, F. & Montanari, A. Human-impacted waters: new perspectives from global high-resolution monitoring. Water Resour. Res. 51, 7064–7079 (2015).

    Article  Google Scholar 

  172. Lu, X. et al. Unveiling hidden migration and mobility patterns in climate stressed regions: a longitudinal study of six million anonymous mobile phone users in Bangladesh. Glob. Environ. Change 38, 1–7 (2016).

    Article  Google Scholar 

  173. Steele, J. E. et al. Mapping poverty using mobile phone and satellite data. J. R. Soc. Interface 14, 20160690 (2017).

    Article  Google Scholar 

  174. Overeem, A., Leijnse, H. & Uijlenhoet, R. Country-wide rainfall maps from cellular communication networks. Proc. Natl. Acad. Sci. USA 110, 2741–2745 (2013).

    Article  Google Scholar 

  175. Colchester, F. E., Marais, H. G., Thomson, P., Hope, R. & Clifton, D. A. Accidental infrastructure for groundwater monitoring in Africa. Environ. Model. Softw. 91, 241–250 (2017).

    Article  Google Scholar 

  176. Fischer, S., Pietron, J., Bring, A., Thorslund, J. & Jarsjo, J. Present to future sediment transport of the Brahmaputra river: reducing uncertainty in predictions and management. Regional Environ. Change 17, 515–526 (2017).

    Article  Google Scholar 

  177. Deltares. Delft3D open source community. Delft3D https://oss.deltares.nl/web/delft3d (2021).

  178. Karunarathna, H., Horrillo-Caraballo, J., Burningham, H., Pan, S. & Reeve, D. E. Two-dimensional reduced-physics model to describe historic morphodynamic behaviour of an estuary inlet. Mar. Geol. 382, 200–209 (2016).

    Article  Google Scholar 

  179. Bates, P. D., Horritt, M. S. & Fewtrell, T. J. A simple inertial formulation of the shallow water equations for efficient two-dimensional flood inundation modelling. J. Hydrol. 387, 33–45 (2010).

    Article  Google Scholar 

  180. Stive, M. J. F., Capobianco, M., Wang, Z. B., Ruol, P. & Buijsman, M. C. Morphodynamics of a tidal lagoon and the adjacent coast. in Physics of Estuaries and Coastal Seas 397–407 (eds Dronkers, J., and Scheffers, M.) (1998).

  181. Mutahara, M., Warner, J. F., Wals, A. E. J., Khan, M. S. A. & Wester, P. Social learning for adaptive delta management: Tidal River Management in the Bangladesh delta. Int. J. Water Resour. Dev. 34, 923–943 (2018).

    Article  Google Scholar 

  182. Mutahara, M., Warner, J. & Khan, M. S. A. Analyzing the coexistence of conflict and cooperation in a regional delta management system: Tidal River Management (TRM) in the Bangladesh delta. Environ. Policy Gov. 29, 326–343 (2019).

    Article  Google Scholar 

  183. Garzanti, E. et al. Provenance of Bengal shelf sediments: 2. petrology and geochemistry of sand. Minerals 9, 642 (2019).

    Article  Google Scholar 

  184. Singh, S. K. & France-Lanord, C. Tracing the distribution of erosion in the Brahmaputra watershed from isotopic compositions of stream sediments. Earth Planet. Sci. Lett. 202, 645–662 (2002).

    Article  Google Scholar 

  185. Lupker, M. et al. 10Be-derived Himalayan denudation rates and sediment budgets in the Ganga basin. Earth Planet. Sci. Lett. 333–334, 146–156 (2012).

    Article  Google Scholar 

Download references

Acknowledgements

This research was funded in part by the engineering and consultancy practice Buro Happold, and is an output from the REACH programme funded by UK Aid from the UK Foreign, Commonwealth and Development Office (FCDO) for the benefit of developing countries (Programme Code 201880). However, the views expressed and information contained are not necessarily those of or endorsed by Buro Happold or FCDO, which accept no responsibility for such views or information, or for any reliance placed on them. The authors acknowledge the support of S. Ferguson in the creation of Fig. 4 and I. Bhalla in the creation of Fig. 7b, and the continuous insightful discussions with N. Venn and H. Rich.

Author information

Authors and Affiliations

Authors

Contributions

A.P. conceptualized the research, analysed the literature and wrote the manuscript. S.G., E.B., M.S.A.K. and J.W.H contributed to the discussion and reviewed the manuscript prior to submission. Conceptualization and development of the manuscript were supervised by E.B. and J.W.H.

Corresponding author

Correspondence to Amelie Paszkowski.

Ethics declarations

Competing interests

The authors declare no competing interests.

Additional information

Peer review information

Nature Reviews Earth & Environment thanks R. Sinha, C. Wilson and S. Darby for their contribution to the peer review of this work.

Publisher’s note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Supplementary information

Glossary

Aggradational

Increased land elevation due to the deposition of sediment.

Progradational

Growth of land further out into the sea.

Subaerial delta

The deltaic plains above the low-tide level.

Subaqueous delta

The deltaic plains that lie below low-tide level and extend seaward.

Avulsed

The rapid creation of a new river channel, and abandonment of the former river channel.

Siltation

Increased concentrations of suspended sediments and accumulation of fine sediments within river channels.

Charlands

Sand bars emerging in river channels or riverbanks as a result of sediment accretion.

Polders

Low-lying land enclosed by embankments, providing protection from storm surges and salinity intrusion.

Beels

Shallow wetlands where the water level changes seasonally, supporting dry-season agriculture.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Paszkowski, A., Goodbred, S., Borgomeo, E. et al. Geomorphic change in the Ganges–Brahmaputra–Meghna delta. Nat Rev Earth Environ 2, 763–780 (2021). https://doi.org/10.1038/s43017-021-00213-4

Download citation

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1038/s43017-021-00213-4

This article is cited by

Search

Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing