Abstract:
In many developing countries, some natural areas are faced with gaps in appropriate map coverage mainly on
land use and land cover (LULC) changes. This situation makes it difficult to plan and implement natural environmental
protection and natural resource management programs. Remote sensing and geographic information systems (GIS) are
excellent tools for mapping LULC changes. This study investigated LULC changes in ‘Somone’ coastal lagoon in Senegal
using multisource remote sensed data. Data sets included aerial photographs recorded in March 1954, and February 1978, as
well as satellite images recorded in February 2003 and April 2016. All images were geometrically corrected and segmented.
Photos and/or images interpretations were made with the aid of computer and post-classification change detection technique
was applied to classify multisource data and to map changes. Stratified sampling was used to assess all classification results.
The accuracies of image classifications averaged 65% (1954), 62% (1978), 79% (2003) and 88% (2016). The postclassification analysis resulted in the largest overall accuracy of 66, 72.7, 72.4 and 80.6% for the 1954–1978, 1978-2003
and 2003–2016 image pairs, respectively. Results indicated an increase in Settlements, from 0.29% in 1954 to 9.21% in
2016, the expansion of the Sabkha, from 5.29% in 1954 to 18.48% in 2016. The mangrove forest has experimented a
reduction between 1954 and 1978 (from 4.07% to 0.56%) and a regeneration (linked to the protection and preservation
policies within the protected area) from the year 2003 to 2016 (from 1.44% to 2.65%). However, the forest areas were
greatly reduced (from 51.06% in 1954 to 10.86% in 2016) and replaced by Settlements (urbanization) as well as Croplands.
