Geospatial analysis of temporal difference in ecosystems of coastal areas and the effects on rural communities in Nigeria

Abstract

The coastal ecosystem is affected by a number of complexes and inter-connected physical, chemical,
anthropogenic and biological processes occurring in the atmosphere, land and ocean. The resultant effects of these processes are modifications of coastal ecosystem, morphology and land masses. This study used remote sensing techniques, GIS analysis, intensive field study and soil type data to examine  ecosystem changes taking place in the Nigeria's coastal areas. The implications of these changes on the rain-fed agriculture in particular and rural economy in general were identified. Landsat TM (1985) and Landsat ETM+(2010)were analyzed to identify preliminary ecosystem boundaries. In-depth field studies of selected ecosystem parameters including upper story canopy density, understory characteristics and soil types were used to reclassify and produce final boundaries of ecosystem in the study area. Three inland ecosystems; Freshwater, Tree crop and Agricultural land ecosystems and three shoreline/marine  ecosystem; Mangrove, Nypa and Saltmarsh ecosystem were identified and mapped in the study. The results of the analysis showed that Water body and marine ecosystems displaced the inland ecosystem in the western part of the coastal areas around Ogun, Ondo and Delta states while there was an increase in the inland ecosystems in the delta region around Akwa-Ibom and parts of River states. The depletion of cultivated arable agricultural land and Tree crop/forest were also caused by increase in marine ecosystem, the salt water, and Fresh water ecosystem. These changes have negative impacts on the food security of the rural communities. The paper concluded with recommendations of pro-poor policy targeted at the vulnerable groups in the coastal communities.

Keywords: Ecosystem, Agricultural Produce, Fresh Water Agriculture, Marine Ecosystem