Evaluation of Vegetation – Slope Relationship in Shasha River Basin, Southwest, Nigeria

The analysis of the geographic distribution of vegetation characteristics in relation to environmental factors is key in addressing biodiversity conservation issues. This study identified the distribution of vegetation communities in Shasha River Basin in relation to the spatial variation of slope in the area, with a view to determine the influence of slope on the floristic distribution in the river basin. Field data were collected at 184 randomly determined plots of 100m2. All woody species in each plot were identified to species level, enumerated and recorded. Landsat imagery obtained for the area was classified using supervised classification algorithm to determine forest area while SRTM DEM was used to analyze the topography of the area. Data were analyzed using Principal Component Analysis (PCA) and Pearson Correlation to determine slope influence on vegetation characteristics. The results showed that over 70% of the river basin was forest vegetation. Plants species sampled were a total of 8760 individuals, consisting of 324 species belonging to 81 families. Dominant woody species included Funtumia elastica and Albizia zygia, while dominant understory species included Cyathula prostrata, and Culcasia scandens. The elevation of the area ranged from 56m to 685m above sea level, with most areas having slope of less than 10% rise and southward facing slopes. The PCA showed elevation having impact on vegetation distribution. The study concluded that topography had a low influence on vegetation characteristics. However further research may consider including other environmental factors such as agriculture and anthropogenic activities, to strengthen knowledge on vegetation slope relationships.

Forest, Biodiversity, Topography, GIS, Environment

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