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PAGES Africa
Pan Africa Workshop, July 2004
AN ASSESSMENT OF COASTAL CHANGES IN THE ATLANTIC WESTERN COAST OF NIGERIA
FASONA, M.J; OMOJOLA, A.S; ODUNUGA, S.S, AND AKINTUYI, A.O
Department of Geography
University of Lagos
Lagos, Nigeria
mfasona@yahoo.com
The Mahin trangressive mud coast beach which lies some 100km east of Lagos is one of the four morphological divisions of the Nigerian coastal complex. Natural and anthropogenic activities (mainly oil and gas exploration) are causing environmental changes and severe land degradation around the study area. Landcover features generated from the 1960s 1:50,000 topographic base maps were overlayed with landcover features generated from Landsat ETM satellite imagery acquired in 2002 for change analysis. The result was integrated with base geology data for comparison of intensity and susceptibility of different geological classes to land degradation.
Agriculture as a driver of deforestation increased from 7% to 18% between the time periods. This gave way to reduction in forest lands from 49% to 43%. The combine influence of natural and anthropogenic driving factors have produced degraded land classes such as devegetated lands, submerged lands, salt water impacted lands, and burrow pit/excavated lands on abandoned beach ridges and general alluvium. Furthermore, most of what used to be natural streams and rivulets are now dredged either to route pipeline from oil well locations to the flowstations or as oilwell slots during exploration. Results of these are ecological migration of inhabitants, socio-economic stress and shifts, loss of several small lakes/ponds, landscape fragmentation, ocean water incursion into land areas and ecological disruptions.
Landcover of Mahin Mud beach Coast 1960 & 2002
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