Geomorphological processes and their connectivity in hillslope, fluvial, and coastal areas in Bangladesh: A review
Abstract Geomorphological knowledge is critical in understanding watershed scale surface processes, including steep mountainous areas and flat lowlands, particularly if the mid- and downstream areas are densely populated and hazard assessments are highly required. However, our knowledge about such s...
| Main Authors: | , |
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| Format: | Article |
| Language: | English |
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SpringerOpen
2022-07-01
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| Series: | Progress in Earth and Planetary Science |
| Subjects: | |
| Online Access: | https://doi.org/10.1186/s40645-022-00500-8 |
| _version_ | 1811222341517049856 |
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| author | B. M. Refat Faisal Yuichi S. Hayakawa |
| author_facet | B. M. Refat Faisal Yuichi S. Hayakawa |
| author_sort | B. M. Refat Faisal |
| collection | DOAJ |
| description | Abstract Geomorphological knowledge is critical in understanding watershed scale surface processes, including steep mountainous areas and flat lowlands, particularly if the mid- and downstream areas are densely populated and hazard assessments are highly required. However, our knowledge about such surface processes has relatively been limited in some areas in South Asia due likely to the lack of comprehensive studies of geomorphology and related fields. This article undertakes an overview of the geomorphological processes of the disaster-prone deltaic landscape of the Ganges–Brahmaputra–Meghna (GBM), particularly focusing on fluvial processes. The area locates in the downstream of the watershed system including Himalayan Mountains and highly connected with the upper basin morphodynamics, hydrology, and sediment flux. The previous studies are summarized at different geomorphic settings concerning hillslopes, fluvial plains, and coastal areas to provide clarity about the geomorphic processes linking erosion-prone upstream source areas to deposition-dominated downstream areas. The review found that most of the geomorphic researches in Bangladesh are exploring landslide inventory and susceptibility mapping in hilly areas; river channel or riverbank shifting, riverbank erosion and accretion in fluvial environments; watershed morphometric analysis and geomorphic unit identification in plain land; and coastline shifting or coastal erosion and accretion in coastal environments at a small scale. Then, we discuss the fluvial dynamics and sediment transport of the GBM river system to address the knowledge gap in the context of deltaic plain land in Bangladesh, where upstream fluvial sedimentation processes impact the geomorphic connectivity from Himalayan to the Bay of Bengal. Although some studies on the fluvial dynamics and sediment dispersal in the upstream GBM river basin are present, the fluvial processes in the downstream domain of Bangladesh are not fully understood with a limited number of research with field-based approaches. Some future perspectives of geomorphic research in Bangladesh are then mentioned to understand better the complex geomorphological settings in the entire GBM watershed and to strengthen the existing research capacity. This review will also develop a holistic understanding of fluvial geomorphic processes of the GBM River to the policymakers and may be helpful to improve the transboundary river basin management policies or strategies. |
| first_indexed | 2024-04-12T08:14:15Z |
| format | Article |
| id | doaj.art-33defc40973c404287c8b99d336cc498 |
| institution | Directory Open Access Journal |
| issn | 2197-4284 |
| language | English |
| last_indexed | 2024-04-12T08:14:15Z |
| publishDate | 2022-07-01 |
| publisher | SpringerOpen |
| record_format | Article |
| series | Progress in Earth and Planetary Science |
| spelling | doaj.art-33defc40973c404287c8b99d336cc4982022-12-22T03:40:51ZengSpringerOpenProgress in Earth and Planetary Science2197-42842022-07-019112210.1186/s40645-022-00500-8Geomorphological processes and their connectivity in hillslope, fluvial, and coastal areas in Bangladesh: A reviewB. M. Refat Faisal0Yuichi S. Hayakawa1Graduate School of Environmental Science, Hokkaido UniversityFaculty of Environmental Earth Science, Hokkaido UniversityAbstract Geomorphological knowledge is critical in understanding watershed scale surface processes, including steep mountainous areas and flat lowlands, particularly if the mid- and downstream areas are densely populated and hazard assessments are highly required. However, our knowledge about such surface processes has relatively been limited in some areas in South Asia due likely to the lack of comprehensive studies of geomorphology and related fields. This article undertakes an overview of the geomorphological processes of the disaster-prone deltaic landscape of the Ganges–Brahmaputra–Meghna (GBM), particularly focusing on fluvial processes. The area locates in the downstream of the watershed system including Himalayan Mountains and highly connected with the upper basin morphodynamics, hydrology, and sediment flux. The previous studies are summarized at different geomorphic settings concerning hillslopes, fluvial plains, and coastal areas to provide clarity about the geomorphic processes linking erosion-prone upstream source areas to deposition-dominated downstream areas. The review found that most of the geomorphic researches in Bangladesh are exploring landslide inventory and susceptibility mapping in hilly areas; river channel or riverbank shifting, riverbank erosion and accretion in fluvial environments; watershed morphometric analysis and geomorphic unit identification in plain land; and coastline shifting or coastal erosion and accretion in coastal environments at a small scale. Then, we discuss the fluvial dynamics and sediment transport of the GBM river system to address the knowledge gap in the context of deltaic plain land in Bangladesh, where upstream fluvial sedimentation processes impact the geomorphic connectivity from Himalayan to the Bay of Bengal. Although some studies on the fluvial dynamics and sediment dispersal in the upstream GBM river basin are present, the fluvial processes in the downstream domain of Bangladesh are not fully understood with a limited number of research with field-based approaches. Some future perspectives of geomorphic research in Bangladesh are then mentioned to understand better the complex geomorphological settings in the entire GBM watershed and to strengthen the existing research capacity. This review will also develop a holistic understanding of fluvial geomorphic processes of the GBM River to the policymakers and may be helpful to improve the transboundary river basin management policies or strategies.https://doi.org/10.1186/s40645-022-00500-8Ganges–Brahmaputra–Meghna (GBM)BangladeshSatellite remote sensingFluvial processesSediment dispersalLandslides |
| spellingShingle | B. M. Refat Faisal Yuichi S. Hayakawa Geomorphological processes and their connectivity in hillslope, fluvial, and coastal areas in Bangladesh: A review Progress in Earth and Planetary Science Ganges–Brahmaputra–Meghna (GBM) Bangladesh Satellite remote sensing Fluvial processes Sediment dispersal Landslides |
| title | Geomorphological processes and their connectivity in hillslope, fluvial, and coastal areas in Bangladesh: A review |
| title_full | Geomorphological processes and their connectivity in hillslope, fluvial, and coastal areas in Bangladesh: A review |
| title_fullStr | Geomorphological processes and their connectivity in hillslope, fluvial, and coastal areas in Bangladesh: A review |
| title_full_unstemmed | Geomorphological processes and their connectivity in hillslope, fluvial, and coastal areas in Bangladesh: A review |
| title_short | Geomorphological processes and their connectivity in hillslope, fluvial, and coastal areas in Bangladesh: A review |
| title_sort | geomorphological processes and their connectivity in hillslope fluvial and coastal areas in bangladesh a review |
| topic | Ganges–Brahmaputra–Meghna (GBM) Bangladesh Satellite remote sensing Fluvial processes Sediment dispersal Landslides |
| url | https://doi.org/10.1186/s40645-022-00500-8 |
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