[ Dynamique des flèches sableuses des Rivières du Sud, de la basse Casamance (Sénégal) au Rio Gêba (Guinée Bissau): Approche par télédétection ]
Volume 37, Issue 3, October 2022, Pages 622–634
Dome Tine1, Mbagnick Faye2, Mamadou Thior3, and Guilgane Faye4
1 Université Cheikh Anta DIOP de Dakar, Département de Géographie, Laboratoire de Télédétection Appliquée (LTA), BP 5005 Dakar, Senegal
2 Université Cheikh Anta DIOP de Dakar, Département de Géographie, Laboratoire de Climatologie et d'études environnementales (LCE), BP 5005 Dakar, Senegal
3 Université Cheikh Anta DIOP de Dakar, Département de Géographie, Laboratoire de géographie physique, BP 5005 Dakar, Senegal
4 Université Cheikh Anta DIOP de Dakar, Département de Géographie, Laboratoire de géographie physique, BP 5005 Dakar, Senegal
Original language: French
Copyright © 2022 ISSR Journals. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
The sedimentary dynamics of the littorals studied is governed by the northern swell which induces a north-south littoral drift and the continental sedimentary contributions transported essentially by the rivers. The aim of this study is to analyse the evolution of sandy spits in the northern part of the Rivières du Sud. The methodology adopted is based on diachronic mapping using Landsat satellite images acquired in 1973, 1986, 2003 and 2018. The results show that the morphological evolution of the Sankoye Spit and the Bird Peninsula is marked by the extension of their spatial coverage. The statistics for the Bird Peninsula show an extension of 116.89 ha between 1973 and 1986, a gain of 220 ha between 1986 and 2003 and a regression of 70.53 ha between 2003 and 2018. The Sankoye spit shows an elongation of its distal end in the direction of the dominant longshore sediment transport, thus dragging the mouth of Kalissaye progressively southwards. Its spatial and temporal evolution is marked by a spatial extension which goes from 603.32 ha in 1973 to 716.25 ha in 2018. For the tip of Cap Roxo, the statistics indicate an extension of 38.19 ha between 1973 and 1986, a regression of 7.75 ha between 1986 and 2003 and 2.02 ha between 2003 and 2018.
Author Keywords: Evolution, remote sensing, sediment dynamics, morphodynamics, Southern rivers.
Volume 37, Issue 3, October 2022, Pages 622–634
Dome Tine1, Mbagnick Faye2, Mamadou Thior3, and Guilgane Faye4
1 Université Cheikh Anta DIOP de Dakar, Département de Géographie, Laboratoire de Télédétection Appliquée (LTA), BP 5005 Dakar, Senegal
2 Université Cheikh Anta DIOP de Dakar, Département de Géographie, Laboratoire de Climatologie et d'études environnementales (LCE), BP 5005 Dakar, Senegal
3 Université Cheikh Anta DIOP de Dakar, Département de Géographie, Laboratoire de géographie physique, BP 5005 Dakar, Senegal
4 Université Cheikh Anta DIOP de Dakar, Département de Géographie, Laboratoire de géographie physique, BP 5005 Dakar, Senegal
Original language: French
Copyright © 2022 ISSR Journals. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Abstract
The sedimentary dynamics of the littorals studied is governed by the northern swell which induces a north-south littoral drift and the continental sedimentary contributions transported essentially by the rivers. The aim of this study is to analyse the evolution of sandy spits in the northern part of the Rivières du Sud. The methodology adopted is based on diachronic mapping using Landsat satellite images acquired in 1973, 1986, 2003 and 2018. The results show that the morphological evolution of the Sankoye Spit and the Bird Peninsula is marked by the extension of their spatial coverage. The statistics for the Bird Peninsula show an extension of 116.89 ha between 1973 and 1986, a gain of 220 ha between 1986 and 2003 and a regression of 70.53 ha between 2003 and 2018. The Sankoye spit shows an elongation of its distal end in the direction of the dominant longshore sediment transport, thus dragging the mouth of Kalissaye progressively southwards. Its spatial and temporal evolution is marked by a spatial extension which goes from 603.32 ha in 1973 to 716.25 ha in 2018. For the tip of Cap Roxo, the statistics indicate an extension of 38.19 ha between 1973 and 1986, a regression of 7.75 ha between 1986 and 2003 and 2.02 ha between 2003 and 2018.
Author Keywords: Evolution, remote sensing, sediment dynamics, morphodynamics, Southern rivers.
Abstract: (french)
La dynamique sédimentaire des littoraux étudiés est régie par la houle du Nord qui induit une dérive littoral Nord-sud et les apports sédimentaires continentaux transportés essentiellement les cours d’eau. Cette étude a pour but d’analyser l’évolution des flèches sableuses dans la partie septentrionale des Rivières du Sud. La méthodologie adoptée repose sur une cartographie diachronique à l’aide des images satellitaires Landsat acquises en 1973, 1986, 2003 et 2018. Les résultats montrent que l’évolution morphologique de la flèche de Sankoye et de la presqu’île aux oiseaux est marquée par l’extension de leur emprise spatiale. Les statistiques de la presqu’île aux oiseaux indiquent une extension de 116,89 ha entre 1973 et 1986, un gain de 220 ha entre 1986 et 2003 et une régression de 70,53 ha entre 2003 et 2018. La flèche de Sankoye affiche un allongement de son extrémité distale dans le sens du transport sédimentaire longshore dominant, entraînant ainsi l’embouchure de Kalissaye progressivement vers le Sud. Son évolution spatio-temporelle est marquée par une extension spatiale qui passe de 603,32 ha en 1973 à 716,25 ha en 2018. Pour la pointe du Cap Roxo, les statistiques indiquent une extension de 38,19 ha entre 1973 et 1986, une régression de 7,75 ha entre 1986 et 2003 et 2,02 ha entre 2003 et 2018.
Author Keywords: Evolution, télédétection, dynamique sédimentaire, morphodynamique, Rivières du sud.
How to Cite this Article
Dome Tine, Mbagnick Faye, Mamadou Thior, and Guilgane Faye, “Dynamics of the sandy spits of the Rivières du Sud, from lower Casamance (Senegal) to Rio Gêba (Guinea Bissau): Approach by remote sensing,” International Journal of Innovation and Applied Studies, vol. 37, no. 3, pp. 622–634, October 2022.
