Processus morphodynamiques et sédimentaires dans les mangroves en érosion de Mayotte, océan Indien
The Island of Mayotte, in the Indian Ocean, is characterized by a highly diversified shoreline comprising numerous mangrove zones set within a vast coral reef and lagoon complex. Many of these mangroves show a clear regression with significant geomorphological implications. Field experiments were co...
| Main Authors: | , , |
|---|---|
| Format: | Article |
| Language: | fra |
| Published: |
Éditions en environnement VertigO
|
| Series: | VertigO |
| Subjects: | |
| Online Access: | https://journals.openedition.org/vertigo/20531 |
| _version_ | 1797223481788596224 |
|---|---|
| author | Matthieu Jeanson Franck Dolique Edward J. Anthony |
| author_facet | Matthieu Jeanson Franck Dolique Edward J. Anthony |
| author_sort | Matthieu Jeanson |
| collection | DOAJ |
| description | The Island of Mayotte, in the Indian Ocean, is characterized by a highly diversified shoreline comprising numerous mangrove zones set within a vast coral reef and lagoon complex. Many of these mangroves show a clear regression with significant geomorphological implications. Field experiments were conducted in order to document beach morphological changes and to determine hydro-sedimentary processes. Hydrodynamic measurements showed the marked effect of the mangrove vegetation distribution on wave energy attenuation. In mangrove areas, wave energy reduction reaches over 90 %, compared to 35 % in mangrove-free areas. Morphological observations have shown that the mangrove retreat is accompanied by erosion of the muddy-sandy substrate by waves which rework and concentrate the sand into well-defined bars, whereas the mud is dispersed towards the lagoon. The sand bars progressively migrate shoreward as swash bars that are built up into beach ridges by waves behind the subsisting mangrove fringe. Continuous beach ridge accretion leads to burial and asphyxia of mangrove root systems, further leading to mangrove mortality. This study highlights the role of mangroves, which exert significant control on the activation of coastal geomorphic processes and intertidal sedimentation. These processes perfectly reflect the notion of biogeomorphological adjustments inherent in these coastal systems. |
| first_indexed | 2024-03-08T02:28:27Z |
| format | Article |
| id | doaj.art-e61bfb66f5ca47238e046e4902e4f8c3 |
| institution | Directory Open Access Journal |
| issn | 1492-8442 |
| language | fra |
| last_indexed | 2024-04-24T13:37:55Z |
| publisher | Éditions en environnement VertigO |
| record_format | Article |
| series | VertigO |
| spelling | doaj.art-e61bfb66f5ca47238e046e4902e4f8c32024-04-04T09:08:18ZfraÉditions en environnement VertigOVertigO1492-844218210.4000/vertigo.20531Processus morphodynamiques et sédimentaires dans les mangroves en érosion de Mayotte, océan IndienMatthieu JeansonFranck DoliqueEdward J. AnthonyThe Island of Mayotte, in the Indian Ocean, is characterized by a highly diversified shoreline comprising numerous mangrove zones set within a vast coral reef and lagoon complex. Many of these mangroves show a clear regression with significant geomorphological implications. Field experiments were conducted in order to document beach morphological changes and to determine hydro-sedimentary processes. Hydrodynamic measurements showed the marked effect of the mangrove vegetation distribution on wave energy attenuation. In mangrove areas, wave energy reduction reaches over 90 %, compared to 35 % in mangrove-free areas. Morphological observations have shown that the mangrove retreat is accompanied by erosion of the muddy-sandy substrate by waves which rework and concentrate the sand into well-defined bars, whereas the mud is dispersed towards the lagoon. The sand bars progressively migrate shoreward as swash bars that are built up into beach ridges by waves behind the subsisting mangrove fringe. Continuous beach ridge accretion leads to burial and asphyxia of mangrove root systems, further leading to mangrove mortality. This study highlights the role of mangroves, which exert significant control on the activation of coastal geomorphic processes and intertidal sedimentation. These processes perfectly reflect the notion of biogeomorphological adjustments inherent in these coastal systems.https://journals.openedition.org/vertigo/20531erosionmangroveIndian OceanmorphodynamicMayotte islandbiogeomorphology |
| spellingShingle | Matthieu Jeanson Franck Dolique Edward J. Anthony Processus morphodynamiques et sédimentaires dans les mangroves en érosion de Mayotte, océan Indien VertigO erosion mangrove Indian Ocean morphodynamic Mayotte island biogeomorphology |
| title | Processus morphodynamiques et sédimentaires dans les mangroves en érosion de Mayotte, océan Indien |
| title_full | Processus morphodynamiques et sédimentaires dans les mangroves en érosion de Mayotte, océan Indien |
| title_fullStr | Processus morphodynamiques et sédimentaires dans les mangroves en érosion de Mayotte, océan Indien |
| title_full_unstemmed | Processus morphodynamiques et sédimentaires dans les mangroves en érosion de Mayotte, océan Indien |
| title_short | Processus morphodynamiques et sédimentaires dans les mangroves en érosion de Mayotte, océan Indien |
| title_sort | processus morphodynamiques et sedimentaires dans les mangroves en erosion de mayotte ocean indien |
| topic | erosion mangrove Indian Ocean morphodynamic Mayotte island biogeomorphology |
| url | https://journals.openedition.org/vertigo/20531 |
| work_keys_str_mv | AT matthieujeanson processusmorphodynamiquesetsedimentairesdanslesmangrovesenerosiondemayotteoceanindien AT franckdolique processusmorphodynamiquesetsedimentairesdanslesmangrovesenerosiondemayotteoceanindien AT edwardjanthony processusmorphodynamiquesetsedimentairesdanslesmangrovesenerosiondemayotteoceanindien |