The Application of GIS and Remote Sensing in a Spatiotemporal Analysis...
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dominated by accretion phenomenon noticed throughout the coastline. The mean
rate of shoreline change was for the first time positive and estimated at 1.04 m/year
with a maximum accretion of about 7.29 m/year and over 32.519 ha of accreted
surfaces while erosion ranges from −0.1 to −5.88 m/year with a loss of 6.943 ha but
a positive sedimentary balance of 25.576 ha. Therefore, it clearly appears that the
phenomenon of erosion has seriously regressed compared to the previous time
series of 1978–1988 and 1988–1998. This regression proved that efforts have been
made in terms of coastline management because in 2005, the National Adaptation
Plan to climate change was launched with a particular interest in securing the ur‑
gent protection of coastal localities such as Rufisque. From 2008 to 2018, the mean
coastline change was estimated at 0.23 m/year attesting to a positive sedimentary
balance with the dominance of the phenomenon of accretion mainly felt in the lo‑
calities of Rufisque and the tourist destination of Toubab Dialaw thanks to coastal
protection facilities (dykes, groynes and riprap) while the villages of Bargny and
Yene experienced recrudescence of erosion ranging from −2.26 to −1.64 m/year.
Compared to 1998–2008, it obviously appears that accreted areas have regressed
while erosion is taking place.
The results arising from the analysis of coastline changes from 1978 to 2018 are
showing two general trends:
– intense erosion process going from 1978 to 1998 with a peak mean of coast‑
line retreat of −6.95 m/year,
– accretion process from 1998 to 2018 with a maximum mean of about
1.04 m/year.
Fig. 13. Ongoing erosion at Rufisque and Bargny Guedj
(author’s field visit – August 2020)
However, it has been noticed in the field that the phenomenon of erosion is still
persisting along the coastline of Rufisque with serious damage inflicted on coast‑
al communities. Figure 13 offers a view of the disastrous effects of coastal erosion
across Rufisque’ coastline.
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dominated by accretion phenomenon noticed throughout the coastline. The mean
rate of shoreline change was for the first time positive and estimated at 1.04 m/year
with a maximum accretion of about 7.29 m/year and over 32.519 ha of accreted
surfaces while erosion ranges from −0.1 to −5.88 m/year with a loss of 6.943 ha but
a positive sedimentary balance of 25.576 ha. Therefore, it clearly appears that the
phenomenon of erosion has seriously regressed compared to the previous time
series of 1978–1988 and 1988–1998. This regression proved that efforts have been
made in terms of coastline management because in 2005, the National Adaptation
Plan to climate change was launched with a particular interest in securing the ur‑
gent protection of coastal localities such as Rufisque. From 2008 to 2018, the mean
coastline change was estimated at 0.23 m/year attesting to a positive sedimentary
balance with the dominance of the phenomenon of accretion mainly felt in the lo‑
calities of Rufisque and the tourist destination of Toubab Dialaw thanks to coastal
protection facilities (dykes, groynes and riprap) while the villages of Bargny and
Yene experienced recrudescence of erosion ranging from −2.26 to −1.64 m/year.
Compared to 1998–2008, it obviously appears that accreted areas have regressed
while erosion is taking place.
The results arising from the analysis of coastline changes from 1978 to 2018 are
showing two general trends:
– intense erosion process going from 1978 to 1998 with a peak mean of coast‑
line retreat of −6.95 m/year,
– accretion process from 1998 to 2018 with a maximum mean of about
1.04 m/year.
Fig. 13. Ongoing erosion at Rufisque and Bargny Guedj
(author’s field visit – August 2020)
However, it has been noticed in the field that the phenomenon of erosion is still
persisting along the coastline of Rufisque with serious damage inflicted on coast‑
al communities. Figure 13 offers a view of the disastrous effects of coastal erosion
across Rufisque’ coastline.